Volume 7, Issue 1

A dynamic simulation and modelling of ethylene bulk polymerization in an autoclave reactor are presented in this paper, based on a kinetic model. This simulation is done for mono- and bi-functional initiators, and results show that application of the bi-functional initiators cause an increase in ethylene conversion. The presented model shows very good results for high temperature and low temperature, in comparison with experimental data in the literature.

In the present study Psyllium was modified with acrylamide through chemically induced graft co-polymerization, under the influence of vacuum using potassium persulphate as an initiator. Graft copolymers were further crosslinked with hexamethylene tetramine for their application in removal of water from different water-oil emulsions. The hydrogel was found to be selective in its absorption and maximum absorption of water was found to be 3020%.

The cross-linked poly(esterurethanes) (PEU) based on unsaturated oligo(alkyleneester)diol (OAE) are presented. OAE was prepared from adipic acid, maleic anhydride and ethylene glycol and then characterized by elemental analysis, FTIR, 1 H NMR and 13 C NMR spectroscopy in account of double bonds and -COOH end groups. The synthesis of PEU was conducted in two steps. In the first step the prepolymers, containing free NCO or OH groups, were obtained via the reaction of OAE with 4,4`-diphenylmethane diisocyanate (MDI) used in excess. The cross-linking was achieved in the next step, in which the prepolymers were dissolved in methyl methacrylate (MMA) of concentrations in the range of 30 to 50 wt% in the presence of 1 wt% of methyl ethyl peroxide and 0.003 wt% of cobalt (II) 2-ethylhexanoate. It is proved that both chemical structure and MDI content in prepolymer influence the static and dynamic mechanical properties and thermal stability of the poly(esterurethanes).

Phenol-formaldehyde (PF) resin is used here for making thermosetting composites along with environmentally friendly coal tar pitch(CTP). These PF-CTP composites are made with dual objectives of using environment-friendly CTP to improve the electrical and physical properties of PF resin and to reduce cost of PF resin for final applications. The composites are prepared by a two-step method using standard compression molding technique. Comparing the properties of the samples containing varying amount of CTP with pure PF resin as the reference sample, significant improvements in electrical properties like surface resistivity, volume resistivity and dielectric strength are observed with the increase in amount of CTP. The waterproofing tendency also improved as the amount of CTP is increased. The best properties are observed for the thermosetting composition with 40 phr of CTP.

Room-temperature 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid (IL) reduces friction and wear of epoxy resin/AISI 316L stainless steel contacts when used as neat external lubricant. In order to study the internal lubricant performance of IL, variable concentration epoxy+IL dispersions containing 0.5-3.3 wt.% IL were obtained by mechanical mixing and casting. SEM cryofracture and EDS show dispersed rounded IL particles within the epoxy matrix. The new dispersions have slightly lower Tg and hardness values than the unmodified resin. Fracture modes and tensile strength are similar for epoxy and epoxy+2.7%IL, although the elongation at break reduces in presence of IL. Pin-on-disc tests show that dry friction coefficients decrease exponentially as the IL proportion increases and wear resistance improves in several orders of magnitude for a critical IL concentration of 2.7 wt.%. Wear mechanisms are discussed on the basis of SEM and AFM observations. The surface modification of the new dispersions gives lower static and dynamic friction coefficients when sliding against steel or polytetrafluoroethylene sheets under mild conditions.

Fluorescent polystyrene was synthesized by Atom transfer polymerization with a novel 1,8-naphthalimide derivative as initiator. The optical characteristics of initiator and obtained polystyrene in DMF solution are discussed. Results indicate that both initiator and polystyrene can emit intensive green luminescence at 520 nm, but the polymer has a higher quantum yield and energy yield.

Plasma polymerization (PP) afforded amine as well as carbonyl containing films which are suitable for use in microarray analysis. The polymerization process with acetone (AC), ethylenediamine (EDA) and diethylamine (DEA) has to be performed in the presence of argon as a carrier gas to be successful. Different activation steps of the polymer based support yield surfaces which differ significantly in their elemental composition after the PP step. Angle dependent XPS proves a take off angle dependence of the carbonyl PP film in contrast to a homogeneous PP film for amine functionalized PP layers while microarray experiments have been successful for both functional films.

Epoxidized natural rubber was prepared by performic acid epoxidation. It was then blended with calcium carbonate dispersion in latex state, which was later coagulated and dried. Rheological properties in terms of Mooney viscosity and shear flow properties were determined. We found that at a given shear rate, the Mooney viscosities, shear stress and shear viscosity increased with increasing levels of epoxide groups in the ENR molecules and increasing loading levels as well as decreasing particle sizes of CaCO 3 . This is attributed to increased level of chemical interaction between polar functional groups in the ENR molecules with increase in the epoxide content. This gives rise to greater chemical interaction between the ENR and CaCO 3 interface upon increase in amount of CaCO 3 . Greater surface areas of the smaller filler particles also caused higher chemical interaction between difference phases.

The synthesis of imidazole end-capped poly(n-butyl methacrylate)s via atom transfer radical polymerization (ATRP) is reported. n-Butyl methacrylate (n- BMA) was polymerized in isopropyl alcohol (IPA) at different temperatures via ATRP using a new N-heterocyclic functional initiator (1-α-bromoisobutylimidazole, BrBI) in the presence of CuBr/2,2’-bipyridine (bpy) as the catalyst. With this new initiating system, a successful ATRP of n-BMA was carried out, and imidazole endcapped polymers with predetermined molecular weights and low polydispersities (1.1<PDI<1.3) were obtained at low polymerization temperature (below 80 °C). Furthermore, the dependence of both the rate of polymerization and PDI on temperature gave the optimal reaction temperature (50 °C). However, at elevated temperature (especially above 80 °C), some different phenomena appeared in the polymerization: the conversion of monomer remains constant after reaching a maximum value (20%-30%), and the higher the temperature, the lower the conversion obtained.

The described approach allows the determination of homopolymer characteristics from complex electrospray mass spectra of multicharged ions in the range of 5000 to 20000. It makes mass spectrometric characterizations possible where compounds are fragmented under MALDI conditions. The determination is accomplished by simulation of the observed complex mass spectra with an Excel based computer program (PolyCalc). The parameters molecular weight (M), reduced sum of end groups (EG), mean molecular weights and polydispersity (Mn, Mw, PDI) are obtained by recursive iteration.

Two hybrid copolymer series obtained by free-radical copolymerization of methacrylcyclohexyl Polyhedral oligomeric silsesquioxane (POSS) with butyl methacrylate or 2-ethylhexylmethacrylate were characterized by 1 H-NMR spectroscopy, gel permeation chromatography (GPC), X-rays Diffraction (XRD), differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA). Reactivity ratios were calculated by low yield composition data suggesting the formation of random copolymers with low probability of poly-POSS sequences. XRD studies showed the crystallization behaviour of the inorganic phase independently on the POSS content; however sample processing by solvent casting effectively hindered the copolymer self-assembling ability. DSC suggests the formation of polyphasic structures with T g increasing with POSS content, and with endothermal peaks occurring at higher temperature. Finally TGA shows an improved thermal stability of hybrid copolymers with char yield correlated to the level of inorganic phase.

Polymer actuators have received much attention due to their vast potential applications. In this work the preparation of polyaniline nanocomposite actuator is studied. The main objective is to overcome the disadvantages of pristine polyaniline in thermal, mechanical and electroactive properties. Montmorillonite is the best candidate for this purpose. Various polyaniline/modified montmorillonite nanocomposite films were prepared using solution method. The properties of nanocomposites are characterized by X-ray diffractometry, transmission electron microscopy, thermal gravimetric analysis, dynamic mechanical analysis, conductivity measurement and cyclic voltammeter. The effects of actuator length and applied scan rate as well as the response of applied potential in actuating applications were investigated. The results show that the structure of nanocomposite is exfoliated. Adding organoclay to polyaniline matrix regardless of decreasing its conductivity; increases the stiffness of the actuator resulting in lower bending level in a linear manner. It reduces the required time to reach the maximum bending, also recovery bending time, i.e. actuator response. Increasing the applied scan rate decreases the actuator bending. Also increasing the length of actuator increases the amount of nanocomposite actuator bending in a linear manner.

In this work the preparation and evaluation of molecularly imprinted polymers (MIPs) based on 2-hydroxyethylmetacrylate (HEMA) for selective recovery of cholesterol from aqueous media are reported. HEMA was used as functional monomer in order to maximize the hydrogen bond forming both in prepolymerization complex and in rebinding experiments which were performed in polar solvents; in particular, an acetonitrile:water (7:3 v/v) mixture was employed. The templating effect is clearly seen in the capacity of the synthesized polymers to bind cholesterol, and their selectivity was evaluated using two steroids quite similar to cholesterol such as progesterone and hydrocortisone which are less effectively bound by the matrices.

Diffusion coefficients of four organic solvents: dichloromethane, trichloromethane, tetrachloromethane and n-hexane in polyethylene particles at infinite dilution were determined by use of inverse gas chromatography (IGC). The polymer particles were used as supplied by the producer to pack the chromatographic columns. This allowed a direct measurement of the interested properties in a particle with the same morphology obtained at the reactor outlet. The particle morphology was investigated and classical mathematical model for chromatographic process was adopted based upon the analysis of particle microstructure. It was found that the limitation step for mass transfer was in the polymer matrix rather than in macropores, and when interpreted in terms of diffusion coefficients for spherical particles, the measured diffusion coefficients compared favourably with predicted values from literature relationships and free volume theory.

PU/PMMA hybrid particles are synthesized by using the method of twostep miniemulsion polymerization. In the first step, PU prepolymer is synthesized by isophorone diisocyanates (IPDI) and poly(propylene glycol) (PPG) with methyl methacrylate (MMA) as a solvent. Then the oil phase, including the NCOterminated prepolymer, MMA, hexadecane (HD), a chain extender as 1,4- butanediol (BD) or bisphenol A (BisA), a cross-linking agent trimethylol propane (TMP), and a catalyst dibutyltin dilaurate (SnDBL) is dispersed in the water phase containing SDS. Then the mixtures form miniemulsion by ultrasonication. Two kinds of initiators, BPO and KPS, are applied for the polymerization of MMA. The influences of chain extenders, initiators and PU/MMA weight ratios on the morphology of PU/PMMA latex particles are investigated. Conversion of MMA is measured and discussed. Particle sizes are analyzed by dynamic lighting scattering (DLS) and transmission electron microscopy (TEM). The cross section morphology of the hybrid particles is also characterized by TEM. For BD/BPO and BD/KPS systems, when increasing the load of PU component, PU-rich phase is moved to the outside of hybrid particles. A core-shell structure can be observed. However, for BisA/KPS system, while using hydrophobic bisphenol A as chain extender of PU, the boundary of PMMA and PU phases is not clear. A more homogeneous structure of hybrid particles is obtained.

Chitosan (CH) and hydroxypropylcellulose (HPC) adsorb water easily by hydrogen bonds formed with hydroxyl and amide groups present in their structures. Heat of adsorption is a thermodynamic parameter which is used to estimate the type of adsorbate molecule bond on a solid surface, among the others. Adsorption of water from vapour phase on chitosan, hydroxypropylcellulose and blends of both biopolymers in the form of films were carried out. Isotherms of water adsorption in the samples were described by the GAB equation. Correlations between mass fraction of chitosan in the sample (w f ) and the values of GAB coefficients were obtained. From parameter c in the GAB equation mean heat of adsorption of the first monomolecular layer of water molecules E1, and pure molar heat of adsorption q were determined.

The creep behavior of a commercial grade polycarbonate was investigated in this study. 10 different constant stresses ranging from 8 MPa to 50 MPa were applied to the specimen, and the resultant creep strains were measured at room temperature. It was found that the creep could be modeled linearly below 15 MPa, and nonlinearly above 15 MPa. Different nonlinear viscoelastic models have been briefly reviewed and used to fit the test data. It is shown that the Findley model is a special case of the Schapery model, and both the Findley model and the simplified multiple integral representation are suitable for properly describing the creep behavior of the polycarbonate investigated in this paper; however, the Findley model fit the data better than the simplified multiple integral with three terms.

Polypyrrole (PPy) dispersion was prepared using FeCl 3 ·6H 2 O as oxidant in the presence of sodium dodecylbenzenesulfonate (SDBS) as surfactant. The formation of the micelles and the electrostatic interaction between PPy and SDBS were considered the driving forces for the formation and stability of the dispersion. UV/Vis/NIR, FTIR spectra and SEM images were studied to confirm the structure and morphology of the PPy dispersion, respectively. Polymerization of pyrrole under different preparation conditions including the concentration of the surfactant, the pyrrole monomer and the oxidant and also the addition of acid were carried out in order to investigate their effects on the stability and average particle size of the dispersions. The conductivity of the resulting PPy particles was measured and a comparison between the PPy and polyaniline dispersion formed with SDBS as surfactant was also given.

Synthesis, swelling properties and thermoresponsive behavior of a new class of hydrogels based on high molar mass polyglycidol are presented. High molar mass polyglycidol was synthesized by coordination polymerization. Thermosensitive poly(glycidol-co-glycidyl ethyl carbamate)s were obtained via a simple chemical modification of the polyglycidol with ethyl isocyanate. Polyglycidol and poly(glycidol-co-glycidyl ethyl carbamate)s were chemically crosslinked in DMF solution using oligomeric poly(ethylene glycol)-bis-(carboxymethyl ether chloride) as crosslinking agent. The hydrogels of degree of swelling of over 1000% were obtained. Thermoresponsive properties of the networks and the swellingdeswelling behavior of hydrogels in response to cyclic changes of the temperature were studied.

The behavior of poly(vinyl pyrrolidone) (PVP) in methanol was examined using several independent methods. The hydrodynamic radius (Rh) of individual samples, over a range of molecular weights (10,000-360,000), was determined using dynamic light scattering (DLS) measurements. Dynamic Light Scattering (DLS) techniques directly probe such dynamics by monitoring and analyzing the pattern of fluctuations of the light scattered from polymer molecules. Some viscosity measurements were also performed to complete the DLS measurements and to provide more information on the particle structure. The results obtained with PVP-methanol system showed that plotting the variation of intrinsic viscosity versus the logarithm of the molecular mass of this polymer, we observe one crossover point. This crossover point appears when we reach the Θ-solvent behavior and delimit two molecular mass regions. The second order least-squares regression was used as an approach and was in excellent agreement with viscometric experimental results.

The rheological, thermal, tensile and fracture properties of controlledrheology polypropylene processed via organic peroxides have been evaluated. Different concentrations of di-tert-butylperoxide (DTBP) were used in this work. Both melt flow index and the crystallinity index increased slightly with the peroxide content while the melting temperature tend to decrease. This was attributed to the decrease in the molecular weight which mainly affects the amorphous region, especially the entanglement density of this semycrystalline polymer. As a consequence, the tensile stress and strain at break reduced as the peroxide content increased. The elastic-plastic response of the different polypropylenes at room temperature promotes the use of J-integral to determine the fracture toughness. A multiple specimens method was utilized. The crack initiation resistance and the crack propagation resistance were influenced by the molecular weight, decreasing as the peroxide content increased. The micromechanisms of failure were analyzed via scanning electron microscopy.

PET non-wovens were treated with intrinsically electro-conducting polypyrrole (PPy) produced by chemical oxidative in situ polymerization from pyrrole aqueous solution, using Fe 3+ or S 2 O 8 2- as oxidant, and different dopants. The resulting materials have different electrical performances and thermal properties depending on the thickness of the PPy coating, the amount and the type of dopant embedded into the polymer layer, the type of oxidant used and the pH of the polymerization bath. Samples were maintained at different temperatures and humidity with the aim of gathering information about the electrical performance stability in different environmental conditions. Generally, PPy shows conductivity decay when maintained at high temperature, whereas the conductivity slightly decreases when stored for a long time at cold or room temperature. Moreover, the PPy coating enhances the resistance to heat of the PET fibres (i.e. increase in melting temperature).

The physical properties of poly(trimethylene terephthalate) (PTT) fibres were improved by means of vibration in the hot-drawing and annealing, which may be caused by the developed molecular packing. For high-speed spun PTT fibers, it was not until at the take-up speed of 3~4 km/min that the orientation induced crystallization started to emerge due to extensional stress occurred in spin line; confirmed from the results of WAXD and DSC. The PTT fibers obtained at the take-up speeds of 2~3 km/min and then drawn and annealed with vibration possessed low density and weight-crystallinity, but their birefringence was especially high. Moreover, the estimation of both refractive index parallel and normal directions to fiber axis using the interference microscopy showed that the refractive index parallel to the fiber axis was very high, which enhanced the mechanical properties of PTT fiber. Accordingly, the well-oriented chains along the fiber axis allow the PTT fiber to have better physical property such as elastic recovery although the PTT fiber has low density and crystallinity compared to PET and PBT. In effect, the PTT fiber possesses lower birefringence of over 10 times than those of PET and PBT due to its chain conformational characteristics. Therefore, we do suggest that the structural assessment against the subsequent mechanical properties according to various processes in the PTT fiber is preferred to be estimated through the respective refractive indices of parallel and normal to the fiber axis rather than conventional methods such as birefringence, crystallinity, and crystalline orientation.

A hyperbranched (HB) aromatic polyamide (aramid) synthesized from A 2 (p-phenylenediamine) + B 3 (trimesic acid) reactants has been used as Pt nanoparticle support. TEM measurements verified the possibility to obtain a high metallic dispersion (MD) using H 2 PtCl 6 as metal precursor. The amount of Pt retained by the polymer support turned out to be lower than the Pd loading deposited on the same HB aramid from a different metal precursor, i.e. PdCl 2 , under the same exchange and reduction conditions, namely by the procedure reported in a previous paper of ours [1]. Moreover, Pt nanoparticle diameters have been found to depend on the reducing agent used. As compared to bubbling H 2 , NaBH 4 allowed obtaining of metal particles characterized by smaller dimensions.

Reactions of parabanic acid (PA) with ethylene and propylene oxides and carbonates lead to oligomeric products with hydroxyalkyl groups in both cases. The parabanic acid ring undergoes scissions during reactions depending on kind of reagent and reaction conditions. In some cases the trioxoimidazolidine ring remains untouched. Using the MALDI ToF technique the product analysis was performed. The by-products were determined quantitatively by GC. The thermostability of oligomeric products was also determined.

An amphiphilic peptide having alternate sequence of hydrophobic and charged amino acid residues, RFDF16 (CH 3 CO-RFDFRFDFRFDFRFDF-NH 2 ), was designed to form a β-sheet monolayer at the air/water interface. The peptide monolayer was prepared by Langmuir-Blodgett (LB) method. The LB films were transferred onto mica substrates without the compressing process at various pH values in order to investigate a self-organized structure of peptide monolayer. Surface morphology of LB films showed arranged nano-fibers which have differences in interval between fibers and their orientation depending on pH of the subphase. On the other hand, the self-organized nano-fiber was also re-arranged by compressing process. The nano-fibers became elongated and aligned upon compression to higher surface pressures. The exploitation of an electrostatic interaction and compressing process will allow a larger two-dimensionally regulated nano-structure.

Polypropylene / organically modified montmorillonite nanocomposites were prepared using polypropylene-graft-maleic anhydride as compatibilizer by the melt blending method. The structural, mechanical and gas barrier properties of the prepared nanocomposites containing various amounts of organoclay (i.e. 0, 2, 5, 7 and 10 wt%) were investigated to evaluate their potential as food packaging materials. The X-ray diffraction (XRD) profiles of the nanocomposites and the transmission electron microscopy (TEM) micrograph showed that polypropylene chains have intercalated between silicate layers of organoclay. The mechanical properties tests showed that the tensile modulus and strength of the nanocomposites increased on increasing the clay loading, while the strain at the break decreased. The gas permeability tests demonstrated that adding organoclay into polypropylene matrix enhances the barrier property of the matrix against O 2 , CO 2 and water vapour.

Network polymers containing silyl groups were synthesized. Silyl derivatives of 2-hydroxyethylmethacrylate (HEMA), and methacrylic acid (MAA) were copolymerized with 1,2-bis(vinylphenyl)ethane (BVPE) and divinylbenzene (DVB) as cross-linking agents by radical polymerization using α,α′-azobis (isobutyronitrile) (AIBN) as initiator to produce network polymers. Then mesalasine (MZ) were loaded to these network polymers, and amount of drug entrapped was determined. In vitro release studies showed that drug delivery property was modified and showed considerable difference in swelling at pH 1 and 7.4. Incorporation of silyl groups in new macromolecule system modified network polymers for drug delivery. Monomers and polymers were characterized by spectroscopic methods.

A mesoporous silica MCM-48 is used as a reinforcement agent for poly(methyl acrylate) (PMA). Methyl acrylate is introduced into the mesoporous silica that has an interconnected porous structure, allowing monomer diffusion into the pores before the polymerization reaction. In order to improve the silica plus polymer adhesion and to decrease the silica agglomeration, the silanol groups of the silica are functionalized with methyl groups without decreasing significantly the pore size. The silica is characterized by nitrogen adsorption, scanning electronic microscopy (SEM) and infrared (IR) spectroscopy. The nanohybrids so obtained are analyzed by tensile testing, thermogravimetry (TGA), differential scanning calorimetry (DSC) and dynamical mechanical analysis (DMA). The highest improvement of mechanical and thermophysical properties is achieved for nanohybrids containing 5 wt. % mesoporous silica. At 10 % silica, agglomeration of the filler takes place and the dispersed phase is less effective in reinforcing the polymer matrix.

Recent progress in the field of zwitterionic polyelectrolytes is reviewed. This class of polyelectrolytes is only five decades old, since the first synthesis was in 1952. Polycarboxybetaines, polysulfobetaines, polyphosphobetaines and a few more zwitterionic materials compose this class of polymers. In the current search for ‘biomimicking’ materials, this class is particularly important. The responsive properties of polyzwitterions are specific, sensitive and instantaneous to a wide variety of external stimuli, which has been reviewed in this article. The synthesis of polyampholytes and polybetaines (homopolymers, copolymers, block polymers) are reviewed. The exploitation of such materials in solid state conducting materials, chromatographic materials and other applications has been incorporated. The extensive discussion on solution properties, antipolyelectrolytic characteristics and influence of varying class of electrolytes has been qualitative as well as quantitative providing an insight into the importance and relevance of such materials, the block polymers form reversible ‘schizophrenic’ micelles also.

The correlation between surface tension parameters and the chemical composition of polysulfone, chloromethylated polysulfone and quaternized polysulfone membranes, before and after plasma treatment, was investigated. Calculations are based on the geometric mean approach of Owens, Wendt, Rabel and Kälble, as well as on the theoretical methods involving quantitative structureproperty relationships on the basis of the group contribution techniques. The chemical modifications of polysulfone membranes and the low pressure plasma treatment affect the contact angle corresponding to different liquids. Consequently, the total surface tension and the polar component increase with the substitution degree of chloromethylated polysulfone and with the quaternization degree of the ammonium groups, in quaternized polysulfone samples. The plasma treatment modifies the surface energy of the samples, increasing their surface polarity and wettability. Surface wettability trends were also studied by means of the free energy of hydration between compounds and water.

Semi-crystalline polymers can be drawn up to very high draw ratios that involve a complete molecular rearrangement of the chain-folded lamellar morphology into a more or less chain-unfolded fibrillar microstructure. This metamorphosis is likely to take place through an intermediate state of high molecular disorder at a local scale. This is the reason why some authors talk of a strain-induced melting-recrystallization process. In contrast, several structural features occurring at moderate plastic strains are relevant to strictly crystallographic processes. A critical discussion of experimental findings and theoretical approaches is made for pointing out the strength or the deficiency of the different author argumentations. No doubt that both phenomena can occur: crystallographic processes are active at all strain levels whereas meltingrecrystallization is restricted to the post-yield stage accompanied with chain unfolding. Melting-recrystallization is rather a corollary of chain unfolding than a basic mechanism of the plastic deformation. Besides, it may concern only a part of the crystalline phase and can be inhibited under adequate deformation conditions.

Chitosan and 80 % hydrolyzed poly(vinyl alcohol) (PVA) were used to prepare semi-interpenetrating networks of varying ratios of the constituents. The hydrogels were crosslinked using genipin, a naturally occurring nontoxic crosslinking agent. The swelling behavior of these hydrogels was studied in deionized water at 25, 35 and 45 °C and in media of different pH at 25 °C. The swelling behavior of the gels was found to be dependent on temperature, pH of the medium and the amount of PVA present in the gel. States of water in the hydrogels swollen at 25 °C and pH 7 were determined using Differential Scanning Calorimetry (DSC). The amount of freezing water in the swollen hydrogels increased whereas the amount of nonfreezing bound water decreased with the increase in PVA concentration in the gels. The gelation behaviour of the pregel solutions were also studied.

Exfoliated polypropylene/layered silicate nanocomposites and chopped glass fiber reinforced composites were prepared by a melt compounding process using maleic anhydride modified polypropylene (PP-g-MAH). The effect of fillers on morphological and rheological properties in melt mixing of polypropylene matrix with compatibilizer was investigated and compared with various measurements. It was observed that polypropylene/layered silicate nanocomposites exhibited remarkable reinforcement compared with the conventional composites filled with glass fibers which were dispersed at micrometer scale. The nanocomposites had larger storage modulus at low frequency region and outstanding strain hardening behavior than those of pure polypropylene or glass fiber reinforced composites. It was shown that glass fiber reinforced composites had lower elastic properties and steady state elongational viscosities than pure polypropylene melt. Contrary to glass fiber reinforced composites, it was confirmed that 3-dimensional network structure due to strong intermolecular bonding between polypropylene matrix and layered silicates affected particular rheological properties of nanocomposites.

Ionic Liquids (IL)s have been generating increased interest over the last decade. ILs were initially introduced as an alternative green reaction media because of their unique chemical and physical properties of nonvolatility, nonflammability, thermal stability, and controlled miscibility. The step-growth polymerization reactions of 4-phenylurazole (PHU) with various diisocyanates such as hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), and toluylene-2,4-diisocyanate (TDI) were performed in the presence of tetrabutylammonium bromide (TBAB) as a reaction medium with or without dibutyltin dilurate (DBTDL) as a catalyst. The polymerization reaction gave similar results in the presence or absence of DBTDL, indicating that, the catalyst is not needed in this process. The resulting polyureas showed high yields and moderate inherent viscosities in a range of 0.23-0.29 dL/g in N,N-dimethylformamide (DMF) at 25 °C and they are soluble in most polar aprotic organic solvents. This method was compared with the polymerization reaction in conventional solvent such as, N,N-dimethylacetamide (DMAc). In the case of using TBAB, higher yields and inherent viscosities were obtained. All of the above polymers were characterized by FT-IR and thermogravimetric analysis (TGA).

We present the synthesis of polymers by means of self-condensation of ethyl 3-aminophenyl acetate, using HCl as catalyst at high temperature and reduced pressure. This polymer was fractionated by successive precipitation from mixtures of methanol/diethylether of different polarity, yielding three polymeric fractions: Poly A, Poly B and Poly C. Likewise, under the same conditions, 3- aminophenyl acetic acid yields only one polymeric fraction, Poly D. These polymers were characterized by elemental analysis, IR and, in some cases, by 1 H-NMR and X-Ray Photoelectron Spectroscopy (XPS). The obtained results show that polymers can be classified as hybrid materials, because in the backbone, they contain simultaneously the amide and imine groups and, at the end of the chain, they have amine and carboxylic acid functions. High solubility of some of these polymers in DMF or methanol has permitted the determination of viscosities and the preparation of films. Poly B and Poly C films exhibit amorphous morphology; and Poly D display spherullitic-type semi-crystallization pattern. The polymers can absorb solvents and they can swell up forming large-sized gels in DMF and methanol. Besides these polymers have high thermal stability that reaches a weight loss of 11.60% at 353 °C.

High density polyethylene (HDPE)/ZnO composites containing a wide range of ZnO content (1-60 vol%) were prepared by melt compounding. ZnO powders with sizes of ~ 200 nm and ~ 2 μm were employed as reinforcing fillers. The effects of the size and filler particle content as well as annealing treatment on the dielectric and conducting properties of the HDPE/ZnO composites were examined. The results showed that the dielectric constant of HDPE/ZnO composites increased gradually with an increase of the ZnO content. The resistivity of HDPE/ZnO composites can be described satisfactorily by the interparticle distance of filled particles. This behavior is interpreted in terms of tunneling of the electrons through the insulating layer of polymer separating two neighboring ZnO fillers. The correlation between the structure and electrical property of the composites is discussed.

Polymeric hindered amine light stabilizer (HALS), wherein the hindered amine functionality was attached to the brominated ethylene-propylene-diene terpolymer (EPDM) was synthesized. The brominated EPDM was synthesized as an intermediate for the synthesis of a new polymeric hindered amine light stabilizer. The grafting and functionalization reactions were characterized by FTIR and 1 HNMR spectroscopy. The photostabilizing efficiency of this polymeric HALS was studied and compared with conventional HALS under accelerated weathering conditions. The results of the study give evidence for superiority of polymeric HALS over that of melt blended conventional HALS.

Functional nanocomposite nonwoven materials were prepared by surface coating with copper and silver using magnetron sputter coating. The composite nonwoven materials with metallic nanostructures were analyzed and compared by means of atomic force microscopy, energy dispersive X-ray analysis and electrical and optical tests. The observations by atomic force microscopy revealed the formation of functional nanostructures on the fibre surfaces. It was found that copper had more compact structures on the fiber surface than silver under the same sputtering conditions. The transmittance analysis showed that the nonwoven substrates deposited with nanostructural copper showed better ultraviolet and visible light absorption than those coated with silver. The functional nonwoven materials coated with silver had lower electrical resistance than those coated with copper.

Poly(methyl methacrylate) peroxide (PMMAP) was synthesized and used as the initiator in the reversible addition-fragmentation chain transfer (RAFT) polymerization. Methyl methacrylate (MMA) as the monomer and 2-cyanoprop-2-yl 1-dithionaphthalate (CPDN) as the chain transfer agent was used in the polymerization system. The polymerization was successfully initiated by PMMAP while maintaining features of “living”/controlled radical polymerization such as the number-average molecular weights (M n ) increasing linearly with the monomer conversions and low polydispersity index (PDI) values. The results of 1 H NMR and IR spectra confirmed that a small quantity of polymer chains were derived from the PMMAP moieties. The PMMAP can also initiate the RAFT polymerization of styrene (St) and methyl acrylate (MA), and the polymerization proceeded in a “living”/controlled fashion.

High molecular weight α,ω-bis(3-aminopropyldiethoxylsilane) poly(tri fluoropropylmethyl)siloxanes (APTFPMS) were prepared via a “one-step” process, based on the ring-opening polymerization of 1,3,5-tris(trifluoropropylmethyl) cyclotrisiloxane (F 3 ) in the presence of water and 3-aminopropyltriethoxysilane (APTES). GPC, FT-IR and 1 H NMR confirmed the structure of the polymers. It was found that the amount of APTES had significant influence on the reaction rate and the molecular weights of polymers decreased with the increasing amount of water. It was probably because both water and the amino group of APTES favoured generation of hydroxyl ions, which efficiently initiate the polymerization of F 3 to achieve APTFPMS. In order to verify this mechanism, another “two-step” process was also performed: Firstly the α,ω-dihydroxylated poly(trifluoropropylmethyl) siloxanes were synthesized from F 3 catalyzed by both diaminoethane and water, then reacted with APTES to achieve APTFPMS. All the syntheses had high yields and the molecular weight of the polymers ranged from 2000 to 25000.

A bifunctional amido thiophene, namely hexamethylene (bis-3-thiophene acetamide) (HMTA) was synthesized and its copolymer with pyrrole was electrochemically prepared in water/PTSA solvent/electrolyte medium. Sensory behavior of this copolymer against ammonia, methanol, dichloromethane (DCM) and n-hexane vapors was investigated. The methanol vapor, which can form hydrogen bonds with the polar groups on the copolymer surface, showed the maximum response. DCM, which is less polar, yielded relatively lower response than methanol. Hexane, being the non-polar vapor, showed the lowest response.

A novel kind of thermo and pH-responsive hydrogels was prepared by reacting N,O-carboxymethyl chitosan (NOCC) with amino-telechelic poly(Nisopropylacrylamide) (PNIPAAm-NH 2 ) as a drug delivery carrier. The hydrogels were characterized by FT-IR and 1 H-NMR techniques. The phase transition behavior of the hydrogels was found to be dependent on the NOCC/PNIPAAm-NH 2 weight ratio and pH value of the medium. The hydrogels with a higher content of PNIPAAm showed a definite phase transition at 32 °C as it occurs in pure PNIPAAm. For the release study, NOCC-g-PNIPAAm beads were prepared using glutaraldehyde (GA) as a crosslinking agent. The swelling ratio of the beads was higher in pH 2.1 than pH 7.4. Moreover, the swelling ratio of the beads decreased with the increase in PNIPAAm content of the beads. The release profile of NOCCg- PNIPAAm beads showed a slower and controlled release of the entrapped ketoprofen, and found that the release behaviour was influenced by both the pH and temperature of the medium. It is expected that these smart hydrogels may be useful to develop drug delivery systems with improved drug loading capacity and controlled release behaviour.

In the process of polymerization of aniline in aqueous solution, different kinds or volumes of organic solvents were added. The effects of the organic solvents on the morphology, structure, conductivity and water-dispersity of the resulting polyaniline (PANI) were investigated with the aid of SEM, UV-Vis, FT-IR and Raman spectra and conductivity measurements. The results showed that the weak H-bond interactions between PANI and the solvents might play an important role in forming uniform nanofibers with relatively high conductivity and good waterdispersity. However, excessive addition of organic solvents led to the aggregation of the nanofibers and the corresponding PANI had a bad water-dispersity.

Free radical homopolymerization with methylated β-cyclodextrin (CD) complexed myrcene (1a) and co-polymerization of 1a with diethyl fumarate (2a) and styrene (3a) were carried out using redox initiator in aqueous media at room temperature. Control experiments showed that uncomplexed myrcene (1) does not polymerize under similar conditions in water. The polymers obtained were characterized by means of 1 H/ 13 C-NMR spectroscopy, differential scanning calorimetry (DSC) and gel-permeation chromatography (GPC). Additionally, Nisopropylacrylamide containing copolymer was synthesized in water using redox initiator and the lower critical solution temperature (LCST) behaviour was studied.

The application possibilities of preparative size exclusion chromatography for the detailed analysis of polymer analytes are discussed. Using the example of star-shaped polymer architecture, the possibilities of utilizing fractions obtained from preparative size exclusion chromatography and their subsequent off-line characterization with a variety of hyphenated analytic techniques are discussed and compared to one another. It was, for instance, possible to obtain an absolute SEC calibration for the investigated star-shaped polymers that showed very good agreement with theoretical expected values and values obtained by absolute molecular weight determination techniques by analyzing fractions of different molecular weights of this polymer architecture by MALDI-TOFMS in order obtain the M p values required for SEC calibrations. Moreover, the star-shaped polymers were investigated by SEC-viscometry in order to obtain their absolute molecular weight. All analytical results are compared to each other and possibilities as well as limitations are discussed.

Rheological and mechanical characterizations were carried out for carbon nanotubes/poly(ethylene oxide) (PEO) nanocomposites to examine the effect of surface modification of carbon nanotubes on the CNT dispersion state. Residual stress in the gap-wise direction of the nanocomposites was measured using the layer removal method. It was found that the different chemical treatments for CNT surface make a big difference in the dispersion state of the CNTs and that the nanocomposites filled with better dispersed CNTs possess higher storage and elastic moduli. From the rheological observations, rheological percolation structure was found to exist in the nanocomposites, which was confirmed by morphological experiments. The residual stress data showed that stronger residual stress is developed in the PEO nanocomposites by non-isothermal cooling than in pure PEO.

Novel functionalized polyacrylate latex with fluorine and silicon was prepared by semi-continuous dropping technique. 19 F NMR, elemental analysis of the silicon (EAS) and FT-IR measurements prove that 2,2,2-trifluoroethyl methacrylate (TFEMA) and α,ω-bis(hydroxyl)polydimethylsiloxane (PDMSH) is successfully polymerized. TEM demonstrates that the functionalized latex particles were spherical, uniform and stable. Contact angle measurement and surface energy estimation show that the highest water contact of the functionalized latex films were 118.3° and the surface energy was as low as 11.7 mJ/m 2 . Water absorption ratio measurement reveals that the water resistance of the functionalized latex films is improved. The heat resistance of the functionalized latex films does not show a large difference from that of the original polyacrylate in our investigated systems.

A novel hyperbranched polyester was synthesized in bulk from 2,2- bis(hydroxymethyl)butyric acid and two different core molecules (1,1,1-tris- (hydroxylmethyl)propane and 1,3,5-tris(2-hydroxyethyl)cyanuric acid), using ptoluensolfonic acid, scandium trifluoromethanesulfonate, titanium tetrabutoxide and dibutyltin oxide as catalysts and varied reaction temperature and time. At room temperature the samples obtained appeared as glassy, slightly yellow solids, with M n (calculated by 1 H-NMR spectra) in the range 500 - 2000. The degree of branching of the polyesters was determined by 13 C-NMR spectroscopy and was found in the range 0.32 - 0.53. The introduction of the monomer in various steps seems to influence slightly the degree of branching, but has no effect on the molecular weight of these polymers. The polyesters exhibited a good thermal stability, as revealed by TGA technique, and the glass transition temperature, determined by DSC, was found to depend on the molecular weight and the kind of catalyst employed.

Fluorescent nanocapsules containing Eu 3+ complex are prepared by the internal phase separation of poly(methylmethacrylate) (PMMA) within the droplets of oil/water nano-emulsion. The nanocapsules give bright red emission excited by UV irradiation and possess stable fluorescence properties. Their fluorescence intensity is primarily influenced by the emulsifier concentration. It is significant that the fluorescence of the nanocapsules is nearly pH-independent and can be kept for a long time in a wide pH range. In contrast, the fluorescence of Eu 3+ complex is easily quenched in acidic or alkalic medium. The mean nanocapsule size is tunable with the concentration and the mode of emulsifier addition. As soft templates, oil cores have potential applications for the incorporation of functional components or drugs.

Hydrogenated nitrile rubber (HNBR)/clay nanocomposites are prepared using conventional two-roll mill mixing technique. The structure and morphology of nanocomposites are characterized using wide angle X-ray diffraction (WAXD) and transmission electron microscopy (TEM). Both intercalated and exfoliated clay structures are observed in HNBR/clay nanocomposites. The thermal stability of the nanocomposites is studied using thermogravimetric analysis (TGA) and TGA-Fourier transform infrared (FTIR) spectroscopy. The effect of organoclay on physical and mechanical properties of HNBR vulcanizates before and after aging in air, water and oil at 178 °C is also investigated. It is found that adding organoclay in HNBR elastomer greatly improves material thermal stability and aging performance in different medium at elevated temperature.

The preparation of polyester resin blends consisting of an unsaturated polyester resin matrix and rubbery particles comprising three radially-alternating glassy and rubbery layers is described. The morphology of the resin blends was examined by transmission electron microscopy (TEM) while thermal properties were investigated by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). The results show that the particles were prepared with good control of particle size and morphology. DMTA results showed no reduction in the T g of the matrix whilst the shear modulus of modified materials was found to be lower than that of the matrix material.

The structural reorganization of polyoxymethylene powders during sintering has been investigated through a detailed analysis of the SAXS data in order to determine the origin of the mechanical property improvement with regard to the compression-moulded counterpart. Two approaches afford a quantitative evaluation of the structural parameter evolutions. On one hand, the correlation and interface distribution functions were calculated for the samples submitted to various thermo-mechanical treatments. On the other hand, the Hosemann’s paracrystalline model modified with Reinhold distributions of the crystal and amorphous phase thicknesses was used to evaluate the disorder in the lamella stacking. Both approaches suggest that a more perfect and regular crystalline structure with thicker and wider crystals develops in the sintered samples as compared with the parent powders and the material crystallized from the melt. Theses morphological modifications are discussed in relation to the very high stiffness and brittleness of the sintered materials. Two possible mechanisms of coalescence of the powder grains via the crystalline phase are proposed to account for these specific mechanical properties of the sintered materials.

A series of Polyacrylic acid (PAA)/Poly (Sodium-p-styrenesulfonate) (PSS) and Polyacrylamide (PAAm)/PSS semi-IPN hydrogel with different contents of PSS were prepared. The swelling behaviour of PAA hydrogel in alkaline environment was improved while the swelling ratio of PAAm hydrogel was decreased after PSS was added. With the increase of ionic strength in solution, the swelling ratios of PAA/PSS and PAAm/PSS showed a decreasing trend. Moreover the swelling ratio of PAAm/PSS decreased more quickly than that of PAA/PSS. The swelling speed of PAA and PAAm both decreased after adding PSS and a more rapid responsive speed was found in the former system. The experiment of in vitro drug release showed that the drug release speed from PAAM/PSS semi-IPN hydrogel was slower than that from PAA/PSS semi-IPN hydrogel. These results suggested that the polymer composition and the trapped polyelectrolyte made a great influence on the drug release behavior.

In this study, a novel fibrous adsorbent obtained by grafting 4-vinyl pyridine (4-VP)/2-hydroxyethylmethacrylate (HEMA) comonomers onto poly (ethylene terephthalate) (PET) fibers was used for removal of methylene blue (MB) from aqueous solutions through a batch equilibration technique. The Influence of treatment time, pH of the solution, dye concentration, reaction temperature and percent graft yield on adsorbed amount were investigated. 300 min. of adsorption time was found sufficient to reach adsorption equilibrium for MB. It was found that the adsorption isotherm of MB fitted to Langmuir type isotherm. The highest adsorption capacity was found to be 55.33 mg MB per gram adsorbent. The adsorbed amount of MB was much higher on the comonomers grafted PET fibers than on the ungrafted PET fibers. MB was removed by 98 % while the initial dye concentration was at 5 mg L -1 and by 88% at 300 mg L -1 by monomers mixture grafted PET fibers. It was found that the reactive fibers were stable and regenerable by acid without loosing their activity.

We have investigated the viscoelastic properties of poly(vinyl alcohol) (PVA) gels loaded with a polyelectrolyte particle of poly(styrene -co- sodium styrene sulfonate) to find the effect of electric charges on the storage modulus of the gel. The storage modulus decreased with increasing volume fraction of particles, and it was independent of the strain, indicating linear viscoelasticity. The viscoelastic properties of PVA gels containing non-charged particles of aluminium hydroxides were also studied. While the degree of swelling kept a constant value, the storage modulus largely increased with the volume fraction. PVA gels containing noncharged particles underwent a large nonlinear viscoelastic response suggesting the particles connect each other in the gel. Viscoelastic properties of the PVA gel loaded with charged and non-charged particles have also been discussed.

Some poly(alkylene dicarboxylate)s, derived from ethanediol or 1,4- butanediol and different diacids, have been synthesized and analyzed by DSC to determine the correlations existing between the thermal properties and the length of the aliphatic chain. The polymers show crystallization and melting temperatures and enthalpies which increase as the polymethylene segments lengthen, due to the formation of more stable crystals. The samples derived from ethanediol are peculiar; they show reorganization processes during the melting and the melting temperatures are notably higher with respect to those of the other polyesters. This behavior is discussed. Isothermal analysis highlights that poly(alkylene dicarboxylate)s are fast crystallizing polymers. The Avrami analysis suggests a crystallization mechanism characterized by heterogeneous nucleation and three dimensional growth; secondary crystallizations is present only in the samples characterized by short -(CH 2 )- sequences, due to the reorganization of less perfect crystalline forms. A comparative study between the crystallization rates as a function of the undercooling is reported.

To prepare inorganic nanoparticles filled polymer composites, reactive monomer was added to the ingredients prior to manufacturing. The results showed that in-situ graft polymerization of butyl acrylate onto nano-silica occurred during melt compounding with polypropylene matrix. As a result, dispersion of the grafted nanoparticles in the polymer became much more homogeneous than in the case of untreated version, and filler/matrix interaction was enhanced due to the intimate adhesion among the components. Both tensile performance and impact toughness of the composites were improved at rather low filler loading. Compared to the twostep approach developed in our lab, by which nanoparticles are treated by graft polymerization firstly and then mixed with polymer melt, the current one-step method is simpler and able to provide the composites with much higher notched impact resistance.

The influence of HLB (hydrophilic-lipophilic balance) and surfactant blend concentration (SBC) on flocculating performance of latex particles of acrylamide and [2-(acryloyloxy)ethyl]trimethylammonium chloride copolymers with a cationic charge density of 40%, obtained by inverse microemulsion copolymerization by using a surfactant blend of Arlacel 83 and Softanol 90 as emulsifier and Rolling M-245, a mixture of n-decane and n-tetradecane in about 40/60 weight ratio, as oil phase, has been studied for a total comonomer concentration of 32.5% (w/w). Comonomer inverse microemulsion copolymerizations were carried out in the semicontinuous mode by adding continuously an aqueous solution of sodium metabisulfite (SMB) as initiator into stirred inverse comonomer microemulsions. From 7.75 to 8.26, HLB has a strong influence on average molar mass (M w ) and flocculating performance (FP), the higher the HLB the higher the FP. A small decrease in SBC causes a dramatic increase in M w and a decrease in FP although the influence on copolymer viscosity is small. Results are explained in terms of copolymer structuring degree and collapsed state of copolymer chains inside latex particles as well as in terms of the observed composition drift with conversion.

An investigation of the influence of temperature and loading frequencies on the morphological features found on the fatigue fractured surface of chlorinated polyvinyl chloride (CPVC) has been conducted. Single edge notched rectangular coupons obtained by flattening schedule 80 CPVC pipe couplings were subjected to fatigue loading at different temperatures of 0, 23, 40, and 70 °C and frequencies of 0.1, 1, and 50 Hz. Crack growth in CPVC, involved a combination of shear yielding and crazing processes. At the test temperature of 0 °C and 23 °C, the fatigue crack growth was noted to occur predominantly by shear yielding while crazing played a secondary role. On the other hand at 40 °C and 70 °C, the fatigue crack growth process appeared to predominantly involve a crazing process while shear yielding played a less significant role. Filler material particles played a major role as brittle second phase stress-raiser particles and facilitated craze initiation. i Discontinuous crack growth bands (DGBs) indicating repeated crack arrests were also noted on the fracture surface.

To increase the solubility and produce cationic or ampholytic polymers as beater additives in papermaking from native hemicelluloses, quaternization of hemicelluloses were performed by reacting hemicelluloses with 3-chloro-2- hydroxypropyltrimethylammonium chloride (CHMAC) and preferably with 2,3- epoxypropyltrimethylammonium chloride (ETA) in aqueous sodium hydroxide, homogenously in dimethyl sulfoxide (DMSO), and completely heterogeneously in ethanol/water, respectively. The extent of modification was measured by degree of substitution (DS), and its value of up to 0.55 can be controlled by adjusting the molar ratio of reagent to hydroxyl functionality in hemicelluloses and the concentration of sodium hydroxide. The characterization of hemicellulosic derivatives was performed by elemental analysis, GPC, FT-IR and 13 C NMR spectroscopy as well as thermal analysis. It was found that hemicellulosic polymer was significantly degraded in aqueous sodium hydroxide solution compared with in dimethyl sulfoxide and in ethanol/water systems under the conditions given. The thermal stability of modified hemicelluloses decreased after chemical modification, corresponding to the decreasing M w of hemicelluloses derivatives.

Modification of polymeric materials has been a significant issue over last two decades in many fields of application. Among modification techniques developed to date, surface grafting has emerged as a simple, useful, and versatile approach to improve surface properties of polymers for a wide variety of applications. The synthesis of tethered block copolymer brushes via the use of controlled/”living” free radical polymerization techniques presents many significant advantages over traditional free radical polymerization techniques. This review surveys recent literature on polymer surfaces with graft chains, mainly focusing on grafting methods such as surface-initiated controlled/”living” free radical polymerization via atom transfer radical polymerization (ATRP), nitroxide-mediated radical polymerization (NMRP), reversible addition fragmentation transfer (RAFT) polymerization and iniferter techniques.

Poly(vinyl acetate) (PVAc) is used extensively in coatings, adhesives and films. The carbonyl group (C=O) in the structure of PVAc forms hydrogen bonding with amine and hydroxyl groups and this may also enhance miscibility with polyaniline. Hence, PVAc has been chosen for blending with PANI. Further, PVAc can be used in moisture sensors and after blending with PANI its conductivity would be in semi conducting range with moisture response, which will be suitable for easy measurement. It was expected that, the given blend may give higher conductivity because 1) PVAc and PANI solubility parameter values match closely: the Hilde Brand solubility parameter (δ) of aniline is 21.1 Mpa 1/2 and PVAc is found to be 20 Mpa 1/2 , 2) Its miscibility also increases due to H-bonding forces of attraction observed in amine group of PANI and ‘CO’ group of PVAc. 3) PVAc has excellent sticking properties to different substrates which makes it useful as an adhesive and 4) Work function values of PANI as well as PVAc match closely. It is interesting to mention that PVAc has a low Tg (28 °C) and thus may serve as a polymeric plasticizer for PANI, which would help to improve processability and/or film formation. There are many methods of blending polymers but only limited techniques can be applicable for conducting polymers. PVAc is soluble in high dielectric constant solvent such as methanol. However, PANI is not soluble in this solvent even after modification with suitable dopants. Hence, a new method has been adopted for blending these two components; i.e. the in situ blending method. This system also explains ex-situ blending method, electrical properties and charge transport processes in the blend.

The study of CF 3 OC(O)OO(O)COCF 3 as radical initiator in polymerization of acrylic and methacrylic monomers as acrylic acid (AA), acrylonitrile (AN), 2-hydroxyethyl methacrylate, (HEMA), and methyl methacrylate (MMA), is presented. The reactions were carried out under different conditions in order to explore the efficiency of the initiator. The results demonstrated that the yield and the type of the products (soluble or non-soluble) is dependent on the reactivity and the solubility of the initiator in the monomers, constituting a heterogeneous system influenced by hydrophobic-hydrophilic balance of the species involved.

ε-Caprolactone (CL) was reacted with PGA oligomers in ionic liquids in the presence of Ti(OBu) 4 , both ring-opening polymerization initiator and polyesterification catalyst. 1 H and 13 C NMR studies showed that the fast polymerization of CL was followed by simultaneous slow polyesterification and ester-interchange reactions leading to random PGA/CL copolyesters after 6 h reaction. The nature of the catalyst and the ionic liquid did not influence much reaction rate. Hydroxyacetyl end-groups appeared to be much less reactive than the corresponding hydroxycaproyl end-groups, which were consumed at the beginning of reaction. The 50/50 and 60/40 oxyacetyl (G)/oxycaproyl (L) (mass-%) copolyesters were amorphous, while copolyesters containing larger amounts of G units were semi-crystalline. The variations of the T g of all copolyesters versus composition follow the Flory-Fox law.

An important method used to make medical implants radiologically visible is based on introduction of radiopaque bromine or iodine containing methacrylic monomers. Thus, 2-(2-bromopropionyloxy) propyl methacrylate (BPPM) and 2-(2-bromoisobutyryloxy) propyl methacrylate (BIPM) were synthesized with the aim to use them as radiopaque agents. The free radical initiated copolymerization of BPPM and BIPM with methyl methacrylate (MMA) were performed directly in a thermostatic cell of the NMR spectrometer. The copolymer compositions obtained from 1 H NMR spectra led to the determination of the reactivity ratios (r MMA = 1.08 ± 0.12; r BPPM = 1.01 ± 0.13 and r MMA = 0.95 ± 0.09; r BIPM = 0.95 ± 0.1). The reactivity ratios of these two monomers is similar to that of MMA suggesting that the length of the bromine containing monomers side chain does not affect significantly the reactivity of the methacrylic double bond. From the results we conclude the copolymers to have random structure.

The electrical properties of two types of imidic polymers, i.e. copolymaleimides containing azobenzene groups and epiclon-based polyimides with their corresponding poly(amic acid)s, have been investigated. The dielectric constant and electrical conductance were experimentally measured over the 1-100 KHz frequency range. Also, the dielectric constants for all samples were determined from the experimentally and theoretically evaluated refractive indices at optical frequencies, when Maxwell’s relationship can be applied. From the currentvoltage characteristic I(U), electrical resistance can be determined, providing information on the relationship between the nature of the material and its electric properties. The obtained values show that epiclon-based polyimides and copolymaleimides present higher electrical resistivity than the poly(amic acid)s. The dissipation factor was evaluated, revealing low energy loss under the form of heat in the studied dielectrics. These results show that these polymeric materials are good insulators, which recommends them for microelectronic applications.

Cellulose fibres were prepared from N-methylmorpholine-N-oxide (NMMO) as a direct solvent. The specific chemical properties of NMMO allow in-situ silver particles to be generated during the process of cellulose dissolution. The fibres obtained contained 0.005% (50 ppm) to 3% w/w of silver. The SEM images showed that the silver particles size is in the range between 30 and 330 nm. The antibacterial properties of the cellulose fibres obtained showed their high bioactivity against E. coli and S. aureus bacteria. The mechanical properties, the size of silver crystallites and SEM images of the fibres obtained were examined.

A novel low dielectric constant polymer, plasma-polymerized 1-cyano isoquinoline (PPCIQ) was prepared by plasma polymerization for the first time. The structure and surface compositions of the deposited PPCIQ thin films were investigated by Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). The results show that a high retention of the aromatic ring structure of the starting monomer in the deposited plasma films is obtained when a low discharge power of 15 W was used during film formation. In the case of higher discharge power of 35 W, more severe monomer molecular fragmentation can be observed. The dielectric properties measurements show that a low dielctric constant of 2.62 can be obtained for PPCIQ thin film deposited at 15 W.

Acryl amide grafted Poly(ethylene terephthalate) (AAm-g-PET) fiber was used for covalent coupling of α-amylase. The amide groups of Poly(acryl amide) were converted to the amine groups by Hofmann degradation reaction. The amine groups were activated by glutaraldehyde, before coupling of the enzyme. The free α-amylase and immobilized α-amylase were characterized by determining the activity profile as function of pH, temperature, thermal stability and storage stability. For the immobilized α-amylase, operational stability was also determined. The immobilization of α-amylase on support caused the optimal reaction pH to shift from 5 to 6. The maximum activity of the free and immobilized enzymes occurred at 50 0C. K m for the immobilized system was higher than that for the free enzyme. The activity of the free enzyme ended in 30 days, whereas the activity of the immobilized enzyme lasted for 60 days at storage conditions. α-Amylase immobilized on matrix maintained 40% of its original activity after 30 times of repeated use.

The oxidative polymerization of aniline was monitored by means of open-circuit potential (OCP) measurements of Pt electrodes immersed in an aqueous acidic medium containing different aniline:oxidizer (ammonium persulfate) molar ratios. Thin polyaniline (PANI) films were formed on the Pt electrode surfaces during the OCP measurements, and they were studied by SEM and cyclic voltammetry in a monomer-free solution at different reaction times. A precipitate also obtained during the polymerization process was analyzed by UV-VIS spectroscopy in 1-methyl-2-pyrrolidinone. It is observed that aniline or short oligomeric species are necessary to initiate the growth of a PANI film, which takes place at the first few minutes of the reaction.

Poly(ethylene oxide)-b-poly(N, N-dimethylacrylamide) (PEO-b-PDMA) was synthesized by successive atom transfer radical polymerization (ATRP) of N,N-dimethylacrylamide (DMA) monomer using PEO-Br macro initiators as initiator, CuBr and 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazamacrocyclotetra decane (Me 6 [14]aneN 4 ) as catalyst and ligand.PEO-Br macroinitiator was synthesized by esterification of PEO with 2-bromoisobutyryl bromide. GPC and 1 H NMR studies show that the plot of ln([DMA] 0 /[DMA]) against the reaction time is linear, and the molecular weight of the resulting PDMA increased linearly with the conversion. Within 3 h, the polymerization can reach almost 60% of conversion. PEO-b-PDMA copolymer with low polydispersity index (M w /M n ≈1.1) is obtained. Self-assembly of PEO-b-PDMA in selective solvents is also studied. It could self-assemble into micelles in methanol/acetone (1/10, v/v) solution. TEM analyses of the PEO-b- PDMA micelles with narrow size distribution revealed that their size and shape depend much on the copolymer composition.

Quantitatively, the Semenov diagram of heat generation-temperature relationship is analyzed. Critical transitions of heat regimes during anion-activated polymerization of ε-caprolactam are investigated. Various outcomes as compared with classic cases already discussed by Semenov are observed for the polymerization and crystallization processes running sequentially. It was shown that the critical Semenov parameter holds even for the weak-exothermal polymerization reaction when steep transition from quasi-thermal-low temperature to quasi-adiabatic-high temperature heat regime takes place.

Styrene- butadiene rubber (SBR)/ clay nanocomposites were prepared by mixing the SBR latex with aqueous clay dispersion and co-coagulating the mixture. Tapping mode AFM and XRD were applied to characterize the structure of nanocomposites. It was found that fully exfoliated structure could be obtained by this method only when the low loading of layered silicate (< 10 phr) is used. With increasing the clay content, both non-exfoliated (stacked layers) and exfoliated structures can be observed simultaneously in the nanocomposites. The results of mechanical tests on the vulcanized pure SBR and SBR/ clay nanocomposites showed that the nanocomposites presents better mechanical properties than clayfree SBR vulcanizate. Furthermore, initial modulus, tensile strength, tensile strain at break, hardness (shore A) and tear strength increased with increasing the clay content, indicating the nanoreinforcement effect of clay on the mechanical properties of SBR/ clay nanocomposites. Compared to the clay free SBR vulcanizate, the nanocomposite vulcanizates exhibit a lower tanδ peak value, higher storage modulus and higher tanδ value at the rubbery region (0-60 °C) which indicate that the elastic responses of pure SBR towards deformation are strongly influenced by the presence of nanodisperced natural sodium montmorillonite layers especially completely exfoliated silicate layers.

The terpolymer resin salicylic acid-hexamethylenediamine-formaldehyde (SHMF) was synthesized by the condensation of salicylic acid and hexamethylenediamine with formaldehyde in the presence of a hydrochloric acid catalyst. The number average molecular weight of the resin was determined by non-aqueous conductometric titration. Terpolymer resin was characterized by elemental analysis, infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy and UV- Visible spectral studies. Chelation ion exchange properties have also been studied for Fe 3+ , Cu 2+ , Ni 2+ , Co 2+ , Zn 2+ , Cd 2+ and Pb 2+ ions employing a batch equilibrium method. It was employed to study the selectivity of metal ion uptake involving the measurements of distribution of a given metal ion between the polymer sample and a solution containing the metal ion. The study was carried out over wide pH range and in the media of various ionic strengths. The terpolymer showed a higher selectivity for Fe 3+ , Cu 2+ and Ni 2+ ions than for Co 2+ , Zn 2+ , Cd 2+ , and Pb 2+ ions.

Hollow fibre membranes with more sponge-like morphology and improved gas permeation performance were spun from 20% polyetherketone (PEK) /sulfuric acid (H 2 SO 4 ) dope solution with aqueous sulfuric acid solution as coagulant using dry-jet wet spinning process. The membrane morphology, mechanical properties and gas separation performance (hydrogen, methane and carbon dioxide) of as-spun PEK hollow fibres have been measured using SEM, Instron and gas test rig. Better cross section structures and mechanical properties in as-spun PEK hollow fibres were observed when aqueous sulfuric acid solution replaced water as coagulant (internal and external). The hydrogen/methane selectivity of up to 40 and hydrogen permeation rate of 3.65 GPU obtained in PEK hollow fibre membranes using 30% sulfuric acid solution as internal and external coagulant simultaneously at the bore fluid injection rate of 30 ml/h are higher than those reported in literatures. Furthermore the effects of bore fluid injection rate and various coagulants on the membrane morphology, mechanical properties and gas separation properties were investigated, as well.

Novel main-chain-conjugated poly(fluorene-alt-squaraine) using vinyl as linkage group were synthesized through direct condensation of 9,9’-dioctylfluorene derivates and squaric acid. The resulting polyfluorenes were characterized by NMR and FT-IR. They have good solubility in common organic solvents, good thermal stability and electrochemical reversibility. The structure of donor-acceptor-donor interaction in the polymer backbone resulted in much more red-shifted absorption spectra of 500-1000 nm, and extremely low band gaps of ~1.2 eV have been obtained. Their absorption spectra have large coverage with solar spectrum, suggesting that they are potential materials that can be used in photovoltaic devices.

New novel kinds of thermosensitive hydrogels with supramolecular structures were synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization of N-isopropylacrylamide (NIPAM) and polypseudo rotaxanes in the presence of N,N- methylenebisacylamide (BIS) as a cross-linker. The polypseudorotaxanes were prepared by supramolecular self-assemblies of α- cyclodextrins threaded onto (4A-PEG) polymers. The structure of the hydrogels were characterized in detail with FTIR techniques. The analytical results demonstrated that a channel-type crystalline structure of inclusion complexes (ICs) remains in as-obtained hydrogels. Their swelling behavior was measured gravimetrically in the temperature range from 20 to 60 °C. The supramolecular structured hydrogels by RAFT polymerization (RAFT gels) showed accelerated shrinking kinetics to conventional hydrogel (CG), surprisingly.

The graft polymerization of Styrene and Methyl methacrylate (MMA) onto deproteinized natural rubber latex (DPNR) was carried out using ammonium peroxy disulfate (N 2 H 8 O 8 S 2 ) as an initiator. The suitable reaction conditions based on the higher monomer conversion was determined. The degree of grafting and the copolymers composition of the resultant SMMA-DPNR were obtained using 1 H NMR Spectroscopy. As expected, composition of styrene in DPNR was higher than that of MMA due to the higher reactivity ratio of styrene monomer as compared to MMA monomer and the structure of the NR backbone. The mechanism of seeded emulsion polymerization leading to graft copolymer of styrene and MMA onto NR was studied and elucidated.

Radical dispersion polymerization of styrene in a non-aqueous media in the presence of a solvent for polystyrene was carried out to study the effect of the solvency of the continuous phase on the polymerization kinetics, the particle morphology, the size and the particle size distribution. Either ethylacetate or cyclohexanone was used as solvent in combination with ethanol as non-solvent. The polymerization kinetics is strongly influenced by the solvency of the continuous phase. The rate of polymerization is reduced in the ethanol-cyclohexanone mixture almost by a factor of two relative to the value obtained in the ethanol-ethylacetate system. On the contrary, variations in the initiator and stabilizer concentration have negligible effects on the polymerization kinetics.

Conducting hydrogels, consisting of conductive polymer poly(3,4- ethylene dioxythiophene)/poly(styrene-sulfonate) (PEDOT/PSS) entangled in the polyacrylamide (PAAm) network, were synthesized by UV using potassium periodate as photo-sensitizer initiator. Electrochemical properties of conducting hydrogels were evaluated by cyclic voltammetry measurements at room temperature. Electrochemical tests indicated the rectangular shape of voltammograms. In addition, the charge/discharge time obtained was very short. Both are characteristic of capacitive materials. Additionally, the conducting hydrogels presented practically the same electrochemical behavior and coulombic efficiency (η) of around 100% after 1,000 charge/discharge cycles. This shows that from the electrochemical perspective, the redox processes involved are reversible, even after several charge/discharge cycles, which is indicative of a material with excellent electrochemical properties.

Polypyrrole (PPy) dispersions with high stability were prepared in the mixed aqueous solution comprising an anionic surfactant (sodium dodecyl sulfate, SDS) and a polymeric stabilizer (polyvinyl pyrrolidone, PVP). By choosing proper mass ratios of the surfactant to the monomer, stable dispersions could be obtained owing to the interaction between the two components. The structure, morphology, stability, particle size, polydispersity index and conductivity of the samples obtained from different conditions were investigated. The PPy dispersions prepared from mixed aqueous solutions were much more stable than those from single component solution.

We have studied effects of gamma radiation on mechanical performance of polymer concrete (PC) containing varying concentrations of an unsaturated polyester resin and calcium carbonate. The compressive strength values increase from the zero dose (non-irradiated PC) to 10 kGy; afterwards we find a periodical change as a function of the resin concentration. The highest compressive strength corresponds to the highest resin concentration but the changes are not too large. Compressive strain values also go symbiotically with the resin concentration. All our composites - including irradiated and non-irradiated - have higher strength values than those reported for earlier polyester + concrete materials. The compressive modulus values follow the same pattern as the compressive strength and strain.

The vinyl (tri-isopropoxide silane)-co-methyl methacrylate-co-n-butyl acrylate-co-styrene latex was prepared by emulsion polymerization. The crosslinked structure was formed in the copolymer latex film and the crosslinking degree of the copolymer latex film increases with the increasing vinyl triisopropoxide silane content. The tensile stress and water repellent property were also strengthened, when the vinyl tri-isopropoxide silane was introduced into the copolymer latex film.

This work investigates the distribution between phases of tert-dodecyl mercaptan (t-DDM) in systems containing styrene (St), polystyrene (PS), and polybutadiene (PB) with the aim of studying its effect on the molecular macrostructure of High-Impact Polystyrene (HIPS) produced via the bulk process. Experimental work involved the study of several St/PS/PB/t-DDM blends, and of 2 polymerizations of St in presence of PB (with and without t-DDM). Blends were prepared with increasing PS/St ratios to emulate monomer conversions of 7, 9, 11, 13, and 15%, employing 2 base PSs of different molar masses, and several total concentrations of t-DDM. Measurements by Proton Nuclear Magnetic Resonance ( 1 H NMR) indicate that t-DDM is almost evenly distributed between the phases at room temperature. In addition, for samples taken along the 2 investigated polymerizations, monomer conversion, grafting efficiency, and free PS molecular weights were measured. Theoretical work involved first to model the species partitions through the Flory-Huggins theory [1]; and then, to combine such partition model with a polymerization model extended from that by Casís et al. [2]. Theoretical estimations were in good agreement with experimental determinations. Simulations suggest that t-DDM partition coefficients exhibit a weak dependence with temperature, but a strong dependence with its total concentration. Also, the combined partition/polymerization model indicates that the free PS contained in the occlusion regions exhibits lower molecular weights than that in the continuous matrix.

A series of hydrogels were synthesized: homopolymers of new temperature-sensitive methacrylate macromonomers of ether-ester structure, derived from monomethacrylate of tetraethylene glycol via Michael-type addition - oligo(TTEGMMA), and copolymers of oligo(TTEGMMA) with N-isopropylacrylamide (NIPAAm) or 2-hydroxyethyl methacrylate (HEMA). Hydrogels based on oligo(TTEGMMA) demonstrate broad volume phase transition. Combination of oligo(TTEGMMA) with NIPAAm or HEMA yielded hydrogels having narrower phase transition and lower gel transition temperature (LGTT) up to 43 °C at the most, which is in the range of interest for most biomedical applications.

We report on the preparation of a novel photonic crystal assembled from poly(styrene/α-tertbutoxy-ω-vinylbenzyl-polyglycidol) microspheres. The latex particles were fully characterized in terms of size (271 nm, D w /D n =1.004), electrophoretic mobility (-3.79x10 -8 m 2 V -1 s -1 ) and surface chemical composition (evidence for a PGL-rich particle surface). They were then assembled into 3D colloidal crystal showing an optical stop band in the visible region. The λ max for the Bragg diffraction peak is 570 nm. As the particles under study are highly hydrophilic and biocompatible, this work opens up new opportunities for the design of photonic crystal-based biosensing devices.

This paper deals with the polycondensation between a chiral diacyl chloride (N,N′-Pyromelliticdiimido-di-L-leucine chloride) and six different dihydrazides. The corresponding poly (hydrazide-imide)s which have been obtained in quantitative yields are moderately soluble in polar aprotic solvents, have good thermal stability and optical activity. The synthetic compounds have been characterized by IR, UV and 1 H NMR spectroscopy, elemental analysis and specific rotation. The thermal properties of the polymers (10 and 15) have been studied by thermo gravimetric analysis (TGA) and differential scanning calorimetry (DSC).

This paper describes new superparamagnetic nanoparticles bearing dextran-grafted porphyrins with effective cellular uptake properties. They average 110 nm in diameter and are composed of a 5 nm iron oxide core coated with protoporphyrin-grafted dextrans. These particles show good magnetic properties, are avidly incorporated into cultured cancer cell lines, and thus present a great potential for cellular imaging and photodynamic therapy applications.

In this paper, the thin microcellular poly(ethylene terephthalate)(PET) sheets, having the controlled structures, were prepared by compression molding. The effects of the processing conditions on the microcellular PET tensile properties have been investigated. By comparing the importance of the individual processing parameters, the saturation time was the most important factor to determine tensile modulus, whereas the saturation time and the upper-plate temperature were the most important processing parameters that influence the tensile strength and specific tensile strength. The effects of the microstructure on the tensile properties of microcellular PET were also investigated systematically. The results indicated that the tensile modulus and strength increased with increasing foam density, but decreased slightly with increasing cell size. Following the experimental data, a new model was built to relate the tensile modulus and tensile strength with the foam density and the cell size.

Poly(N-isopropylacrylamide) hydrogels have been successfully modified by concentrated sulfuric acid for the first time. The modified hydrogels displayed faster, larger magnitude and hydration/dehydration dynamic response to temperature cycling without increasing the lower critical solution temperature (LCST). These contributions were attributed to sulphate ester groups resulting from terminal hydroxyl groups of poly(N-isopropylacrylamide). These results may lead to technological application for temperature-responsive thin film and microgel particles with higher surface-to-volume ratio.

An azobenzene-based dithiocarbamate, 4,4'-bis[2-(carbazole-N-dithio formatyl)-2-methyl-propionatyl]-azobenzene (CDMPA), was synthesized and used as the chain transfer agent (CTA) for reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene in anisole solution. Well-defined azobenzene-centered and carbazole-ended polystyrene (PS) with well-controlled molecular weight (Mn) and narrow molecular weight distributions (Mw/Mn) was obtained. The good agreement between the theoretical molecular weight (Mn,th) and the 1H NMR determined molecular weight (Mn,NMR) indicated that most of the polymer chains contained an azo-functional center-group end-capped with the carbazole moieties, which were derived from the RAFT agent. The obtained polystyrene (PS) showed a strong ultraviolet absorption in tetrahydrofuran (THF) and emitted fluorescence after excited by UV-irradiation in N,N’-dimethyl formamide (DMF) solutions. The PS was used as the macro-RAFT agent to carry out the polymerization of methyl acrylate (MA) and N-isopropylacrylamide (NIPAAM). Triblock copolymers (PMA-b-PS-b-PMA), and pentablock copolymers (PNIPAAM-b-PMA-b-PS-b-PMA-b-PNIPAAM) were obtained, respectively. These copolymers were characterized by gel permeation chromatography (GPC), FT-IR spectroscopy and NMR spectroscopy.

The step-mass-thermal transferring meant that for PAN/DMSO/water system, the kinetic of phase inversion and droplet ripening was controlled by employing several consecutive coagulation baths with different concentrations and temperatures. In this way, the morphology of fiber could be adjusted based on modelling. The phase diagram of PAN/DMSO/water was calculated based on Flory-Huggins theory. The mass and thermal transferring was calculated according to Fick’s second law and Fourier heat equation respectively.

The synthesis and radical polymerizations of several acrylamides having Gabapentin(GBP) moieties were examined. The monomers were prepared by the reactions of 1-aminomethyl-1-cyclohexane acetic acid salts with acryloyl chloride in the presence of triethylamine in moderate yields. Radical polymerizations of the monomers were carried out in the presence of AIBN (3 mol%) in Dimethyl formamide (DMF) with moderate yield. The thermal behavior of the polymers was investigated by thermo gravimetric analysis (TGA) and differential scanning calorimeter (DSC) to determine the thermal degradation pattern and glass transition temperature (T g ). The resulting polymers showed a thermal stability up to 400 °C. The glass transition temperatures of the polymers were found not to depend on the substituents of the GBP moieties. Nearly the same TG’s were observed for polymers. We found the molecular weights of the polymers to be between 20700 and 2300 g/mol. We obtained poly(HFCHA) as a water-soluble polymer. Poly(MFCHA), poly(EFCHA) and poly(PFCHA) were soluble in common solvents.

Novel carbon foam with high thermal conductivity is prepared by thermal treating of mesophase pitch under certain temperature and pressure condition. With fractal theory, the thermal conducting property of this novel porous material is discussed. Then we deduce the area fractal dimension of carbon foam. A thermal conductivity model of carbon foam is proposed. The relationship formula of effective thermal conductivity is presented by using thermal resistance method. Through computation, the effective thermal conductivity of carbon foam is acquired. The value of model forecast is consistent with that of the actual observed for carbon foam. This method has provided the theoretical basis for better using its fine heat conduction performance.

Graft copolymers of poly(ethylene-vinyl alcohol)-g-poly(phenyl ethyl methacrylate) copolymers were prepared by a grafting onto method in two steps. In the first step carboxyl terminated poly(phenyl ethyl methacrylate) (PPHETMA) were prepared by solution radical polymerization using 4,4-azobis(cyanovaleric acid) (ACVA) as initiator and thioglycolic acid (TGA) as matched chain transfer agent and then converting carboxyl groups into acid chloride terminated prepolymer by reacting with oxalyl chloride. In the second step acid chloride terminated prepolymers were reacted to the ethylene-vinyl alcohol (EVOH) backbone. Grafting was confirmed by Size Exclusion Chromatography (SEC), Fourier Transfer Infrared spectroscopy (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. Thermal properties of the graft copolymers were studied by Differential Scanning Calorimetery (DSC) and Dynamic Mechanical Thermal Analysis (DMTA).

Brownian-dynamics simulations have been performed for complexes formed by a charged dendrimer and a long oppositely charged linear polyelectrolyte when overcharging phenomenon is always observed. After complex formation the orientational mobility of the individual dendrimer bonds, the fluctuations of the dendrimer size, and the dendrimer rotational diffusion have been simulated. Corresponding relaxation times do not depend on the linear-chain length in a complex and are close to those for a single neutral dendrimer. At the same time fluctuations of the size of a complex are completely defined by the corresponding fluctuations of a linear polyelectrolyte size. Adsorbed polyelectrolyte practically does not feel the rotation of a dendrimer; simulated complexes may be considered as nuts with light core (dendrimer) and heavy shell (adsorbed linear polymer); the electrostatic contacts between dendrimer and oppositely charged linear polymer are easily broken due to the very fast dendrimer-size fluctuations.

In this study, suspension polymerization is described to fabricate microcapsules containing n-hexadecane as phase change material. In the suspension polymerization, casein is employed as emulsifier and stabilizer instead of synthetic surfactant. Microcapsules with polystyrene as shell and n-hexadecane as core have an average diameter of 3~15μm and the size distribution are narrow. Thermal properties are investigated by differential scanning calorimetry (DSC) showing that the microcapsules can store and release an amount of latent heat over a temperature range nearing the melting point of pure n-hexadecane. The latent heat of fusion of microencapsulated n-hexadecane decreases after microencapsulation. The melting point of microencapsulated n-hexadecane is near but higher than that of pure n-hexadecane, and the polymerization time has little effect on the melting point.

HAPAM was successfully prepared in inverse microemulsion. 1 H-NMR, FT-IR, DSC and TG results show that the copolymerization of acrylamide (AM) with DM16 was successful. However, the ratio of AM to DM16 is not calculated exactly due to the low percentage of hydrophobic monomer in polymer. Therein, we only proved the success of the incorporation of DM16 onto polyacrylamide backbone. According to our experiment, the conversions of monomers and molecular weight have a strong dependence on initiator concentration and aqueous phase weight fraction. But it was not completely in accordance with literature. The difference may be ascribed to the major existence of locus of DM16 (at the interface of oil/water or in droplet). Compared with literature, the influence of initiator concentration on particle size was slight due to the high surfactant weight fraction, seeming to appear independent of initiator concentration. When the surfactant weight fraction reaches a certain degree, it did not affect the conversion. For the particle size and molecular weight, it was other way around, suggesting that there was an intense chain transfer reaction to the emulsifier. In this work, we could not calculate the average number of free radical per particle n, because the part of the surfactant in excess recombines to form small micelle and the DM16 may continuously transfer from micelle to another micelle, resulting in difficulty to estimate precisely the number of the particles. This was also reflected in the difference of kinetics between our system and literature. Finally, the occurrence of nucleation at high conversion was proved indirectly.

Free radical copolymerization of styrene (S) and acrylonitrile (AN) in the ionic liquids (ILs) 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM]PF 6 ), 1,3-dimethylimidazolium dimethylphosphate ([MMIM]Me 2 PO 4 ) and 1-ethyl-3- methylimidazolium ethylsulfate ([EMIM]EtSO4) were investigated. 2,2’-azobisiso butyronitrile (AIBN) and dibenzoyl peroxide (BPO) were used as initiators and dimethyl formamide (DMF) and methanol as reference solvents. The influence of the viscosity on the conversion and the molecular weights was studied by variation of the reaction temperature and the IL concentration. At reaction temperatures of 80 - 85 °C already after 30 minutes a conversion of about 80 % and almost a doubling of the molecular weights is reached for the S/AN (50/50 mol%) copolymerization. In addition the copolymerization behavior of S/AN in [EMIM]EtSO 4 was investigated. With increasing concentration of AN in the monomer feed the polymerization rate as well as the molecular weights of the copolymers increase. The influence of the ionic liquid on the copolymer composition, glass-transition temperature and rheological behavior was studied.

New copolymers made of 2-(dimethyl amino) ethyl methacrylate (DMAEM) and isocyanate ethyl methacrylate blocked with methyl ethyl ketoxime (IEMB) was synthesized in various composition ratios in order to obtain water reducible copolymers after acidification. They were characterized by infrared spectroscopy, chemical titration for the determination of amine equivalent weight, and by differential scanning calorimetry (DSC). Calorimetric analysis showed the presence of a former broad endothermal peak followed by a latter, stronger exothermal one, which can be respectively attributed to the deblocking of isocyanate groups and to their subsequent reactions. Some copolymer compositions were dip coated onto microscope glass slides and surfaces were characterized by static and dynamic contact angles, revealing a clear effect of the salifying agent and a likely surface rearrangement of polar groups while in contact with water. Finally, oligonucleotides surface immobilization and molecular recognition capability of the coated glass slides were positively assessed by hybridization tests with fluorescently labelled complementary probes.

The effect of thermoplastic PMMA and clay Cloisite 30B addition on the cure kinetics of an epoxy/amine thermosetting system was investigated using differential scanning calorimetry (DSC) and modelled using a single kinetic model. For obtaining a good agreement between the experimental results and theoretical modeling, it was necessary to separate the ternary system in two formulations: matrix/PMMA and matrix/clay systems. It appeared that the addition of PMMA delays the reaction up to the phase separation phenomenon due to a dilution effect of the reactive species. In opposition, the presence of clays accelerates the reaction (probably due to a catalytic effect of some metals ions introduced with the clay) but it has no sensitive effect on the cloud point conversion in the presence of PMMA. The modeling results are in good agreement with those experimentally obtained.

We reported a chemical approach for the in-situ preparation of conducting polyaniline (PANI)/Fe 2 O 3 composite dispersions using dodecylbenzene sulfonic (DBSA) acid both as dopant and surfactant. The PANI/Fe 2 O 3 composite dispersions were characterized by X-ray diffraction, UV-vis and FT-IR spectra and conductivity measurement. The dispersions showed good stability and existed without precipitate for at least half a year. The gas-sensing behavior of the composite film to 100 ppm of NH 3 was studied through monitoring the change of the resistance.

α-Carboxyl end-functionalized poly(methylidene malonates 2.1.2) were prepared by free-radical polymerization in the molecular weight range 5 000 - 10 000 by using 4,4'-azobis(4-cyanopentanoic acid) as a functional initiator. A functionality of one carboxyl group per chain could be obtained. On the contrary, it was demonstrated that chain transfer functionalization with mercaptans is not applicable in this case. A Michael addition reaction between the mercaptan and the monomer becomes the predominant side-reaction. The corresponding mercaptanmonomer adduct was characterized in detail by 1 H and 13 C NMR.

Protein material resulting from chemical free steam explosion of wool was mixed in different proportion with polyamide 6 in formic acid. The viscosity of the blend solutions decreases with the increase of the protein amount in the blend. Nanofibres produced by electrospinning of these polymer blends show an increase of the filament diameters with increasing protein amounts, except for the 30/70 v/v polyamide 6/protein blend, where nanofibres with “beads” defects were produced. In blend films produced by casting, polyamide 6 crystallize in the form of large spherulites prevalently in the α crystalline structure, while protein is totally amorphous and tends to segregate in the course of drying at room temperature. Otherwise, in electrospun nanofibres polyamide 6 and protein show a better miscibility as suggested by spectroscopic and thermal analysis and polyamide 6 shows a higher thermal stability. Moisture regain and water solubility of blend cast films and electrospun nanofibres respectively were also determined.

The non-isothermal crystallization behaviour of poly(phenylene sulfide) (PPS) in blends with hyperbranched poly(phenylene sulfide) (HPPS) was studied by means of differential scanning calorimetry (DSC). It was observed that the PPS crystallization temperature was found to decrease upon addition of the HPPS. It suggested that the crystallizability was reduced. The Ozawa equation was valid not only for neat PPS, but also for the blends. A notable reduction in Avrami exponents for the PPS/HPPS blend systems suggested that the nucleated process leads to rodshaped growth with thermal nucleation. The cooling crystallization function, which represents the rate of non-isothermal crystallization, was found to decrease with increase in HPPS content. The Ea value increases with the increase in HPPS content. Our results indicated that crystallization of the PPS was hampered by content of hyperbranched poly(phenylene sulfide).

Silicone-urethanes, polymers combining the characteristics of two widely used biomaterials, i.e. polyurethanes and silicones, are highly valued in many applications, including medical implants. To assess properties of these materials in contact with living cells, a set of different silicone-urethane materials, candidates for tissue engineering scaffolds, was synthesized and characterized. Two different oligomeric siloxane diols: Tegomer-2111 (Teg) and KF-6001 (KF), and two different types of diisocyanate, MDI and IPDI, were used in synthesis. Blood platelets adhesion to surfaces of selected materials showed a higher thrombogenicity of material based on Teg. Human fibroblasts were used in in vitro biocompatibility tests. The viability of cells cultured on silicone-urethanes was tested by XTT assay. Teg-based silicone-urethanes showed a significantly higher biocompatibility than those based on KF. Materials based on MDI compared to IPDI were found to be significantly more favoured by cells, not necessarily due to the type of diisocyanate but maybe also because of the necessity of using potentially toxic catalyst which accompanies the use of IPDI. Our studies indicate that silicone-urethanes are potent materials for tissue engineering products development. On the basis of the observations performed in cell culture, Tegomer- 2111 as oligomeric siloxane diol and MDI as diisocyanate are recommended as starting materials for silicone-urethane scaffolds synthesis.

Changes in the microstructure of the free volume and its temperature dependence in ethylene-norbornene copolymer and bisphenol-A polycarbonate due to densification under pressure and swelling with CO 2 gas have been examined using positron annihilation lifetime spectroscopy (PALS) and pressurevolume- temperature (PVT) experiments. Employing the Simha-Somcynsky equation of state the specific hole free and occupied volumes were estimated. From the PALS spectra analyzed with the new routine LT9.0 the size distribution of subnanometre holes and its mean and mean dispersion were calculated. Above T g , the dispersion mirrors the thermal fluctuations in the free volume. From comparison of PALS and PVT data the specific number of holes was estimated. It was found that the occupied volume has a constant and identical compressibility in the glassy and rubbery state. It shows no memory for the history of the glass and mirrors only the pressure and temperature during the measurement. The change in the total volume due to the pre-treatments of the polymers occurs exclusively in the hole free volume V f and the relative change in V f is one order of magnitude larger than in the total volume. PALS data show that the mean hole size and its dispersion in the glassy state is decreased due to densification and increased due to swelling. PVT data show that the volume changes are frozen in the polymer glasses and that, when heating the samples, the volume begins to recover at temperatures ca. 50 K in gas swollen and 20 K in densified polymers below T g . The PALS data show a corresponding behaviour.

Nafion, an ionomer composed of perfluorocarbon backbone and vinyl ether side chains terminated with -SO 3 - groups, has dual solubility parameters, i.e. δ 1 = 9.7 (cal/cm 3 ) 1/2 relating to perfluorocarbon backbones and δ 2 = 17.3 (cal/cm 3 ) 1/2 relating to sulfonated vinyl ether side chains. It had been reported that Nafion molecules aggregated in dilute and semi-dilute water and alcohol solutions. In this study, we report static light scattering (SLS) measurements of dilute Nafion in N,N’- dimethyl formamide (DMF, solubility parameter δ =12.2 (cal/cm 3 ) 1/2 , dielectric constant ε=36.7) and N,N’-dimethyl acetamide (DMAc, δ =10.8 (cal/cm 3 ) 1/2 , ε=37.8) solutions with Nafion concentrations ranging from 0.2 mg/ml to 1.0 mg/ml. The DMF and DMAc solvents have δ closing to δ 1 of Nafion perfluorocarbon backbones and ε much lower than water (ε =78). Thus DMF and DMAc are compatible with Nafion perfluorocarbon and few Nafion molecules aggregate in DMF and DMAc solvents when [Nafion]< 1.0 mg/ml. The lower ε of DMF and DMAc led to low polyelectrolyte effect of Nafion in these two solvents. The obtained M w s of present work were in good agreement with the M w obtained from Nafion in dilute dimethyl sulfoxide (DMSO, δ =12.0 (cal/cm 3 ) 1/2 , ε=46.6) solutions, reported by Lousenberg, using size exclusion chromatography incorporating static light scattering detection. The <RG> data obtained from SLS measurements were compared with the particles sizes of transmission electron microscope (TEM) observations of freeze dried Nafion thin films prepared on copper grids with 0.6 mg/ml Nafion solutions. Comparable results were obtained from these two observations.

The synthesis and second-order nonlinearity study of several new polyphosphazenes were described, which are composed of a new type of Yshaped nonlinear optical (NLO) chromophores attached onto polyphosphazene. They were obtained via a post-azo coupling reaction. The resulting materials were characterized by means of 1 H NMR, 31 P NMR, FT-IR, UV-vis, GPC and DSC. Chromophore contents up to 14 mol% have been realized. The polymers have high glass-transition temperatures, good optical transparency, and the poled film of P3- P8 revealed a resonant d 33 value in the range of 11-42 pm/V by second harmonic generation (SHG) measurements.

Guar gum is a natural polysaccharide that has been explored for various applications. However, there is a limited number of studies in which guar gum has been used as a filler in a polymer. The effect of acetylation of guar gum on its properties as a filler in an unsaturated polyester matrix was studied. The rheology of the uncured composition indicated increased polymer-filler interaction with increased ester content. The tensile and flexural properties increased with the acetylation degree of guar gum; however the impact resistance of the composites was reduced. Excessive esterfication of guar gum was detrimental to the mechanical properties of the composites due to reduced hydrogen bonding resulting in the filler phase having lower integrity. The chemical properties of the composites were also studied as well as the effects of acetylation. Thus, an increase in the hydrophobic nature of guar gum resulted in an increase in the polymer-filler adhesion and interaction but at the same time reduced the hydrogen bonding leading to reduced cohesion of the filler particles. This resulted in reduced mechanical properties of the composites as compared to lower acetylated guar gum based composites.

A route to thermally stable polyimide nanofoams was developed. Nanofoams were prepared from graft copolymers consisting of thermally stable and thermally labile blocks as continuous and disperse phase, respectively. The copolymers were synthesized via reaction of sulfone-based diamines with aromatic dianhydrides through the poly (amic acid) precursor, followed by thermal imidization. Foam formation was achieved by thermolysis of thermally labile block, leaving pores of the size and shape corresponding to the initial copolymer morphology. Polyimide precursors and nanofoams were subjected to a variety of characterization including FT-IR, thermal gravimetric analysis (TGA), dielectric constant, scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The nanofoams showed good processability, high thermal stability, and low dielectric constant which are prerequisites for application in electronic industry.

The effect of bimodality i.e. blending short and long chain (0 to 80 % w/w) silicone prepolymers, and that of concentration of the crosslinker on the tensile properties such as percent elongation at break (%Eb), ultimate tensile strength (UTS), 100 % modulus and elastic modulus (E) has been investigated. It was found out that the greater amount of crosslinker used for crosslinking provide an additional reinforcement to the silicone network whereas bimodality further significantly accentuates this effect. Remarkably, the %Eb of the silicone networks was found to increase to an average of 2.4 times than that of the monomodal network, cured in each of the three series of bimodal networks cured with 3.9, 9.1 and 12.3% of crosslinker. The optimum property in each case was observed at about 70 mol % of P100. The over all order of sensitivity of these properties up to about 70 mol % of short chain prepolymer has been observed to be as: %Eb > UTS > 100% modulus > elastic modulus. It has been shown that in addition to the previously published reports the tensile properties are acutely dependent not only upon the degree of crosslinking and primary molecular weight; but also on bimodality and crosslinker concentration for preparation of the unfilled silicone polymer networks. The concept of phase inversion (or phase transition) associated with the optimum properties in polymer blends has for the first time been applied to the bimodal polymer networks. It has been observed that the maxima in tensile properties generally corresponds to phase inversion which takes place at 0.5 volume fraction (70 mol %) of short chain (P100) prepolymer which is in accordance with the literature for other systems.

In this study, a new neural network quantitative structure-property relationship model for prediction of θ (LCST ) of polymer solutions is presented. The parameters of this model are eight molecular descriptors which are calculated only from the chemical structure of polymer and solvent. These eight molecular descriptors were selected from 3328 molecular descriptors of polymer and solvent available in polymer solution by genetic algorithm-based multivariate linear regression (GA-MLR) technique. The obtained neural network model can predict the θ (LCST ) of 169 polymer solutions with mean relative error of 1.67% and squared correlation coefficient of 0.9736.

Transparent film samples of hydroxyethyl cellulose (HEC) based on solid polymeric electrolytes (SPE) were prepared by the plasticization of HEC with glycerol and addition of lithium perchlorate salt. SPEs with different quantities of glycerol and LiClO 4 were studied by electrochemical impedance spectroscopy (EIS), Dynamic Mechanical Thermal Analysis (DMTA), TGA (Thermogravimetric Analysis) and DSC (Differential Scanning Calorimetry). The ionic conductivity measurements revealed that the sample containing [O]/[Li]=8 and 48% of glycerol showed the conductivity value of almost 10 -4 S/cm at room temperature. The TGA analysis of electrolytes with high plastizant and salt concentrations showed 25% weight loss after heating to 130 °C, which can be related to the liberation of absorbed water. Finally, DMTA measurements showed changes attributed to the glass transition (T g ) evidenced by the decrease in the elastic modulus value and peaks in the tanδ curves. These results demonstrated that HEC is a good material to be used as a matrix for new solid polymeric electrolytes.

Poly (ethylene terephthalate) (PET)/Attapulgite (AT) nanocomposites were prepared via in-situ polymerization. According to the observation of transmission electron microscopy (TEM), attapulgite is well dispersed in the PET matrix in a nanometer scale. The influence of attapulgite content on the nonisothermal crystallization kinetics was studied using a classical Avrami equation with Jeziorny method. The crystalline structures of the pure PET and PET/AT nanocomposites with different amount of AT (0.2%, 0.5%, 1%, 2%) were characterized by differential scanning calorimetry (DSC) and X-ray diffraction (XRD) methods. It was found that the crystallization temperature for PET/AT nanocomposites with 0.2% and 0.5% content of AT were higher than pure PET and the rate of crystallization of all PET/AT nanocomposite samples increased significantly which indicated that attapulgite could be used as an effective nucleating agent in PET. However, with the addition of AT, smaller crystalline size, more crystalline defects and lower degree of crystallization was demonstrated.

The chromatographic stationary phases based on molecularly imprinted monoliths were prepared by free radical polymerization and subsequently characterized. The mixture of commonly used comonomers of ethylene dimethacrylate/methacrylic acid was polymerized in presence of various porogenic mixtures. Tosyl-L-phenylalanine was selected as a model template. Polymerization steps were carried out in the glass columns (i.d. of 3.3 mm) enabling UV initiation. Difficulties encountered with polymerization in situ, e.g. volume contraction and adhesion of polymer onto the glass inner wall, were successfully solved. The morphology of monoliths was investigated by electron microscopy, mercury porosimetry and surface area measurements. The influence of polymerization conditions on monolith morphology and subsequent chromatographic properties was evaluated. Polymers prepared by UV polymerization showed higher total porosity and the most frequent pore radius compared to the same polymers prepared thermally. The prepared monoliths by UV irradiation were also significantly more permeable for mobile phase during the chromatography tests. Morphology of monoliths prepared in dodecanol/toluene porogenic mixture markedly depended on the temperature of polymerization; the most frequent pore radius decreased with increasing temperature. From chromatographic point of view, monolithic columns were tested by separations of standard hydrophobic solutes. Height equivalent to a theoretical plate reached the values of approx. 25 μm, Walters indices of hydrophobicity laid slightly above 3. Prepared monoliths were compared to the conventional columns, filled with the particles prepared from the polymer of the same composition and preparation. In many cases the monolithic columns showed better chromatographic parameters.

Cinnamoyloxy ethyl methacrylate (CEMA) was copolymerized with different monomer feed ratios of octadecyl acrylate (ODA) and crosslinked using azobisisobutyronitrile (AIBN) as the initiator and N,N’,N”-trisacryloyl melanine (AM) or N,N’,N”,-trismethacryloylmelanine (MM) crosslinkers. The networks are characterized by scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). For crosslinked CEMA/ODA copolymer sol fraction values are lower when MM is used rather than AM. The thermal stability of crosslinked network increases with increasing ODA concentration and also in the presence of MM crosslinker, a consequence of higher crosslinking density. SEM results show a porous structure; micropores are formed when ODA contents increases. According to DMA results, the flexibility of the network is enhanced by incorporation of MM rather than AM. Since our crosslinked networks are both flexible and porous, they are applicable as oil sorber networks to alleviate pollution from oil spills.

Optical plastics have been the priority area of research for material scientists worldwide, mainly, to find alternative materials to glass, a conceptual optical material in use over the years. There are numerous advantages of using plastics for optical applications, in particular for ophthalmic applications over glass. Recently, the researchers have been putting their efforts to develop novel plastic materials to meet requirements of ophthalmic industries. The present review compiles the recent developments in the area of optical plastics. The aim is to present the current state-of-the-art in the field, besides analyzing the various aspects of developing optical plastics. The review presents various possible approaches to achieve the desired properties e.g. high refractive index of the optical plastic materials.

Epoxidised natural rubber (ENR) latex could be prevulcanized by employing tert-butyl hydroperoxide/fructose system. By applying the phase transfer/bulk polymerization/ transmission electron microscopy (TEM) technique, the uniform crosslink distribution in peroxide-prevulcanized (PP) ENR particle was observed. However, the membrane layer of protein-lipid complex, originally existing at rubber particle surface, could not be detected. Results implied that the alkoxy radicals penetrated throughout the rubber phase. The diffusion rate of radicals should be equal to that of vulcanization. Under TEM, the uniform mesh-like particle and cluster of the rubber chains were observed in PP(NR/ENR) while micrographs of PP-NR/PP-ENR blends showed only the crosslinked particles whose structure correlated well with that of PP-NR.

Two different types of polyolefine (PO) grafted with itaconic acid as a reactive compatibilizer, polypropylene (PP) grafted with itaconic acid (PP-g-ITA) and high density polyethylene (HDPE) grafted with itaconic acid (HDPE-g-ITA), PP and HDPE grafted with copolymer of itaconic acid and styrene (PP-g-(ITA-St) and HDPE-g-(ITA-St)) were prepared by melt graft technique through reactive type twin-screw extruder. FT-IR and thermal analysis were used to characterize the structure of the graft copolymer. The graft ratio (GR) and melt flow rate (MFR) were determined by non-aqueous titration and melt flow rate analyzer. The effect of the concentration of monomer and initiator dosage on GR and MFR of graft copolymer were studied. Then polyamide 6 (PA 6) blends, PA 6/PP (PA 6/HDPE), that compatibilized with PP-g-ITA (HDPE-g-ITA) were prepared. The morphology of the blends was analyzed by SEM, DSC and Molau tests and the mechanical properties of which were characterized by tensile, impact, and bend tests. The results of mechanical property showed that the impact strength of blends was increased by 50% and 70% after PP-g-ITA and HDPE-g-ITA was used as compatibilizer, but the MFR of blends was decreased. The SEM photographs indicated that the accession of compatibilizer obviously improved binding state between two phases in blends, the size of dispersed phase was reduced evidently and the interface became indistinct. DSC results demonstrated that in the case of PP-g-ITA, glass temperature (T g ) of PA 6 matrix in blends was ascended, melt point (T m ) was improved a little, crystallinity (X c ) was decreased, T m and X c of PP phase was increased; With the accession of HDPE-g-ITA, T m of PA 6 matrix and HDPE phase had almost no change, X c of PA 6 matrix was decreased and X c of HDPE phase was increased.

Precipitation polymerization method is a non homogeneous method in which polymer chains are separated from continuous phase as polymer particles. In this method, all polymerization reactions occur in continuous and polymer dispersed phases based on simultaneous polymerization theory. Hunkeler theory is a perfect "simultaneous polymerization" theory that predicts molecular weights and the rate of polymerization for precipitation polymerization of hydrophilic monomers. In this paper, finite moment method is used to predict features of precipitation polymerization. This model is able to predict number and weight average degree of polymerization in dispersed and continuous phases, polydispersity index (PDI) for two phases and volume fraction of primary and secondary particles. Experimental results are in agreement with the properties of dispersed phase; weight and number average degree of polymerization in the dispersed phase is more than that of degrees of polymerization in the continuous phase. The PDI of polymer formed in the dispersed phase is equal to 2 and that of PDI in the continuous phase is less than 2. Furthermore Hunkeler mathematical model is reviewed critically.

Nanocomposites based on polyamide 6 (PA6) and montmorillonite-type (MMT) commercial clays, either unmodified or organically modified, were prepared by in-situ polymerization of ε-caprolactam (CL). The above materials were characterized in detail by a number of experimental techniques, including transmission electron microscopy (TEM), wide angle X-ray diffraction (WAXD), infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The formation of nanostructured systems was checked not only for the commonly used ω-aminoacid-modified clay, but also for other types of organoclays. In general, a correlation was found between nanoscopic swelling of the clay in molten CL, measured by X-ray diffraction, and level of clay dispersion in PA6. Specifically, with the most swellable clays, completely exfoliated nanocomposites were obtained. However, also layered silicates modified by compatibilizers having carboxy groups, because of the active role of latter in CL polymerization, formed delaminated nanocomposites despite their low degree of swelling in CL monomer. Both molecular mass and crystallinity of the polyamide matrix were found to be strongly influenced by the presence of specific layered silicates. In particular, some characterization techniques (WAXD, FTIR) have evidenced a close relationship between the MMT used and PA6 crystal structure. Namely, PA6 γ-form is promoted by clay with compatibilizer bearing the carboxy group, which is able to induce the polymer to be tethered on the silicate layers, thus provoking conditions of restricted mobility to occur.

The monomer 2,4-dichloro phenyl acrylate (2,4-DCPA) was synthesized from 2,4-dichlorophenol and characterized by conventional methods. The homopolymers of 2,4-DCPA and its copolymers with 8-quinolinyl methacrylate (8- QMA) in different feed ratio were prepared by free radical polymerization using dimethyl formamide (DMF) as a solvent and 2,2’-azobisisobutyronitrile (AIBN) as an initiator. The resulting polymers were characterized by Infrared Spectroscopy. UV spectral data were employed to obtain the reactivity ratios of the monomers, 2,4-DCPA and 8-QMA. The results showed that 2,4-DCPA is more reactive than 8- QMA. Average molecular weights and intrinsic viscosities determined by Vapour pressure osmometer (VPO) lies in the range of 7900 to 10890 and 0.021-0.036 dl.g -1 respectively. Thermal analysis shows that thermal stability of copolymers increases with the increase of 2,4-DCPA. The copolymers also showed antimicrobial activity which increased with increase in 8-QMA content.

In this research, the melt blending technique was used to prepare various polypropylene (PP) based nanocomposites. A commercial organoclay (denoted 15A) served as the filler for PP matrix, and the maleic anhydride modified PP was used as compatibilizer. The specimens were subjected to electron beam (EB) irradiation. The purpose of the study focuses on the influences of EB irradiation on the thermal stability and mechanical properties of the nanocomposites. The morphology of the nanocomposites was studied using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The XRD and SEM results showed that these nanocomposites are best described as intercalated systems. PP/Clay nanocomposites showed good thermal stability in the TGA analysis. TGA data at 500KGy showed that the EB irradiation has negative effect on thermal stability of the nanocomposites. Mechanical testing showed that the EB irradiation strongly influences the mechanical properties (tensile strength, Young’s modulus and hardness) of PP/Clay nanocomposites. The value of tensile strength decreases remarkably for all specimens with increasing irradiation dose up to about 550 KGy, but this reduction for nanocomposites with 3% clay is less than that of the pure PP/PP-g-MA blend. In higher irradiation doses, reduction in tensile strength of PP nanocomposites is less than that of the pure PP/PP-g-MA blend. Optimum irradiation dose of Young’s modulus for PP/Clay nanocomposites with 5% clay is 450 KGy. The hardness of the nanocomposites with 5% clay was found to decrease with increase in irradiation dose.

In this work, a novel water-managing superabsorbent composite was prepared by graft copolymerization reaction using acrylic acid (AA) and acrylamide (AM) as the monomers, calcium montmorillonite (Ca-MMT) as an inorganic component and sodium humate (SH) as fertilizer, and well characterized by means of Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The effects of the reaction temperature, neutralization degree of AA, amount of crosslinker, initiator, Ca-MMT and SH on water absorbencies were systematically investigated. The water absorbencies of the superabsorbent composite synthesized under optimal conditions with a Ca-MMT content of 20 wt% and an SH content of 30 wt% are 615 g g -1 and 45 g g -1 in distilled water and in 0.9 wt% NaCl solution, respectively. The swelling behaviours of the superabsorbent composite in various cationic salt solutions (NaCl, CaCl 2 and FeCl 3 ) were also investigated and it was found that at the same saline concentration (> 0.1 mmol L -1 ), the effect of three cationic salt solutions on the swelling capability has the following order: NaCl < CaCl 2 < FeCl 3 . Here, it is worthy to point out that the water absorbency and swelling behaviours of the developed composite were improved by introducing simultaneously Ca-MMT and SH into PAA-AM network in comparison with that of incorporated single with Ca-MMT or SH.

Soluble copolymers of a series of bromine-containing (N-maleimido phenoxy) silane (BMS) monomers with styrene (St) were synthesized by radical polymerization in toluene using 2,2’-azobisisobutyronitrile (AIBN) as initiator. The comonomer reactivity ratios were calculated by the conventional Fineman-Ross and Kelen-Tüdos methods and a nonlinear least-squares Tidwell-Mortimer method. The glass transition temperatures (T g ’s) and thermal degradation of copolymers were determined by differential scanning calorimetry (DSC) and thermo-gravimetric analysis (TGA) respectively. The introduction of silane side-chain into maleimide (MI) monomers changed the comonomer reactivity ratio with styrene from alternating to azeotropic copolymerization. The curves of T g ’s versus the different compositions of the above synthesized St-BMS copolymers matched a modified T g ’s equation as a increase in the effect of weight ratio on alternating-segment, and an S-shaped curve of deviation in comparison with the Fox’s equation. The MIsegments within these copolymers exhibited a good compatibility and, the flame retardancy of polystyrene could be enhanced via the introduction of Si/Brcontaining maleimide.

A metallocene catalysed linear low density polyethylene (mLLDPE) was mixed with very low amounts of bitumen (1-2%) as an additive. Bitumen interacts with mLLDPE giving rise to a dying effect, which turns the originally white mLLDPE extrudates into black. No slippage is observed during extrusion and sharkskin is postponed as bitumen is added. “Melt strength” values of the blends, determined in melt spinning experiments, are very similar to those of mLLDPE. Accordingly good performance is expected in film-blowing process. Tensile modulus values are higher than 10 9 Pa. Bitumen emerges as an alternative to carbon black powder currently used to obtain black polymer films.

Poly(oxy-1,4-phenylene carbonyl-1,4-phenylene oxy-1,4-phenylene carbonyl-2,6-naphthalene carbonyl-1,4-phenylene) or 2,6-PEKEKNK is a polymer of the poly(aryl ether ketone) family differing from PEKEKK by the presence of a naphthyl group linked at positions 2 and 6 to the two ketone groups. It is synthesized by electrophilic precipitation polycondensation of 2,6- naphthalenedicarboxylic acid chloride with 4,4’-bis-(4-phenoxy) benzophenone in the presence of aluminium chloride. The dimensions of the orthorhombic unit cell determined from an initially amorphous, stretched film are: a = 0.778 nm, b = 0.613 nm, c = 5.52 nm. In contrast with PEKEKK no signs of polymorphism were found for 2,6 PEKEKNK. Its glass transition and melting temperatures are 20 °C and 2 °C above those of PEKEKK, respectively.

The viscoelastic behavior of hydrogenated nitrile butadiene rubber (HNBR) was studied over a range of temperatures and shear frequencies. Dynamic mechanical properties were studied and modelled using the generalized Maxwell model and the Williams-Landel-Ferry equation. A fitting algorithm was developed to provide the best agreement between the experimental data and the model results. In addition to dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) was applied. The HNBR structure was characterized by X-ray diffraction (XRD). The developed model exhibited an excellent agreement with either isothermal or dynamic experiment data, yet only up to the rubbery plateau, after which a structure ordering occurred. This was explained by the cyano group secondary bonding and consequentially the cross-linking between HNBR chains. A molecular modeling simulation was made to confirm the cross-linking. The effect of peroxide cross-linking agents in a compound resembled the one usually observed in the filler formulated compounds.

In this study, processing-structure relationships in polypropylene (PP)/waste ground rubber tire powder (WGRT) foams made using supercritical carbon dioxide as a physical blowing agent were investigated. In order to investigate the relationship between structure and properties of PP/WGRT foams, it was necessary to make samples with a wide range of controlled structures. For this reason, a systematic investigation of the relationship between processing conditions and structure was performed based on a statistical experimental design. Regression analysis was conducted on the data and expressions were developed to quantify the relationships between structural parameters and processing conditions. The samples were saturated with carbon dioxide at high temperature and high pressure and the saturated specimens were expanded during the pressure-quench process. The importance of the individual processing parameters was determined. Statistical analysis of data showed that saturation temperature was the most important factor determining cell size, cell density and relative density. By controlling the foaming conditions, PP/WGRT samples having the same foam density and different cell size or having the same cell size and different foam density were produced.

In this study, poly(vinyl alcohol) were cross-linked with boron in varying concentrations and blend fibers were obtained with diameters ranging from 0.3 μ to 4.0 μm with the use of electrospinning process. The resulting product was characterized by SEM, DSC, and FT-IR techniques. There is no beading tendency in either boron doped or undoped fibers. When the amount of boric acid in PVA solutions was increased the conductivity of the polymer decreased. The data indicated the existence of boron oxide in the polymeric structure and the formation of B-O-C bond. SEM micrographs reveal that higher viscosity favors the formation of thicker fibers. Boron addition seems to disturb the easy detachment of the fibers from the tip of the Taylor Cone

PETs/PHB blends with different compositions were produced by “casting” method. The blends were investigated by TGA, DSC, 1 H and 13 C NMR and FTIR. Phase separation occurred during blend preparation. PETs and PHB were present in both formed phases. The phases presented different thermal stabilities unrelated to phase component concentration changes. The miscibility study by DSC showed that PHB-phase rich blends are immiscible, whereas the PETs-rich phase blends are miscible. The 1 H NMR spectra of the miscible blends exhibited a peak close to the PHB methylene signal, which is in accordance with the interaction between the PETs SO 3 - groups and the PHB carbonyl groups. This interaction result in a shift of the PHB carbonyl group absorption band in the FTIR spectra and a variation in the chemical shift of the PHB carbonyl group resonance peak in solid state 13 C NMR. No specific interaction was observed for the immiscible blends.

Ion-exchangers, adsorbents, supported catalysts, etc, derived from porous copolymer beads are employed as medium in fine chemical separation processes. In these processes the exchange of reagents completes earlier in the smaller beads than in the larger beads in the same lot, which reduces the separation efficiency. So, it is potentially advantageous to preferentially introduce the macropores in the larger beads, as the macropores provide fast access to the reagents into the inner portions of the beads. In this study, camphor-a sublimable organic compound was employed as a diluent to create porosity in 4-vinylpyridinedivinylbenzene copolymer beads produced by o/w suspension polymerization technique. Camphor preferentially introduced macropores in the larger beads in the reaction. The results are explained on the basis of removal of diluent by sublimation phenomenon from the polymerizing droplets at a faster rate from the smaller beads as compared to the larger beads in the same batch.

Telechelic vinyl oligomers terminated with hydroxyl groups were prepared by free radical copolymerization of styrene (S) and acrylonitrile (AN), initiated by azoester-2,2’-azobis[2-methyl-ω-hydroxy-oligo(oxyethylene) propionate] [AIB-OOE(400)], carried out in N,N-dimethylformamide. The reactivity ratios r S =0,225 and r AN =0,722 for styrene and acrylonitrile, respectively, were evaluated by Kelen-Tüdős method. The glass transition temperatures (T g ) of the copolymers were determined by differential scanning calorimetry. T g values varied with the copolymer composition in the range of 60-82 °C and the maximum T g value was obtained for copolymer with 60 mol% AN.

A novel dithioester, bearing anthracene as Z group, benzyl anthracene-10-carbodithioate (BAC) was successfully synthesized and used as the RAFT agent for the RAFT polymerizations of styrene (St). The results indicated that the polymerization presented the characteristics of “living”/controlled radical polymerization. 1 H NMR characterization of obtained polystyrene confirmed that most of the polymer chains were end-capped by the anthracene moiety. The successful chain extension experiment further demonstrated the “living” character of the polymer. The fluorescence investigation of the polymers contained an anthrancene moiety of BAC in the chain end expressed enhanced fluorescence property than that of BAC in CHCl 3 solution.

Methoxy poly(ethylene glycol)-b-poly(D,L-lactide-co-glycolide-co-ε- caprolactone) diblock copolymers, designated as MPEG-b-PDLLGCL, with different MPEG block lengths and DLL:G:CL ratios were synthesized via ring-opening polymerization in bulk using MPEG and stannous octoate as the initiating system. The diblock copolymers were characterized using a combination of FT-IR, 1 HNMR, GPC and DSC. The percentage yields of the diblock copolymers were in excess of 90%. 1 H-NMR analysis confirmed that the PDLLGCL blocks contained at least some random character. From their DSC curves, the diblock copolymers were amorphous in morphology. Their glass transition temperatures decreased as the MPEG block length increased and as G and CL units were incorporated.

Isotactic polypropylene (PP) nanocomposites containing 0.1, 0.3, 0.5 and 1.0 wt % silver (Ag) nanoparticles were prepared via melt compounding in a twin-screw extruder followed by injection molding The effects of the Ag nanoparticle additions on the structure and mechanical behavior of PP were studied using DSC, WXRD, optical microscopy, tensile and Izod impact techniques. DSC and WXRD measurements showed that the addition of only 0.1 wt% Ag nanoparticles promote the formation of β-form PP. Further increasing Ag content would not lead to additional increase of the β-PP phase content. The induced β- form PP phase is beneficial to enhance the impact strength and tensile ductility of the PP/Ag nanocomposites.

Starch was sulphated with pyridine.SO3 complex in the microwaveassisted solid state processes in multimodal microwave oven and, for comparison, also on convectional heating blends of solid reagents. Starch was less hydrolysed in microwave-assisted reactions. The degree of the esterification of the sulphuric acid anhydride depended to a lesser extent on the reaction time and the power applied, and more essentially on the reagent ratio, that is, dose of the sulphating agent. Its higher doses favoured depolymerization and esterification leading to diesters, that is, crosslinking.

This work describes the synthesis and characterization of poly(vinyl alcohol)-boric acid (PVA-BA) sphere-like beads. The PVA-BA beads were prepared by the dropwise addition of PVA aqueous solutions to a boric acid solution under constant stirring and controlled temperature. Different temperatures for bead formation as well as PVA with several hydrolysis degrees were used and tested. PVA with several hydrolysis degrees were characterized regarding molecular mass and intrinsic viscosity, while characterization of PVA-BA beads was carried out using thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The results obtained with TGA have shown that structural changes occurs in PVA following the reaction with boric acid and that the spheres formed are thermally stable, whereas SEM analysis demonstrated that symmetric sphere-like beads were formed, with considerable porosity, which are requisite for solid supports when applied to effluent treatment. Trace element extraction tests were carried out using inductively coupled plasma mass spectrometry (ICP-MS). Without the addition of a chelating agent, no significant extraction occurred from acidic solutions, while after the addition of ethylenediaminetetracetate, less than 10% of the trace element content was extracted from the aqueous phase by the PVA-BA beads. However, after the addition of ammonium O,O-diethyldithiophosphate (DDTP), over 10% of As, Co, Cr, Fe, Sr and Zn, 40% of Cd and 70% of Pb were extracted from acidic solutions, even without any further optimization. The results have shown that the synthesized PVA-BA beads are potential alternatives for trace element extraction in effluent treatment.

Middle molecular weight epoxy resin was used to modify the properties of polybutylene terephthalate (PBT) and glycidyl methacrylate-functionalized acrylonitrile-butadiene-styrene (ABS-g- GMA) blends. Rheological tests showed that the complex viscosity and storage modulus of PBT increased with the addition of epoxy resin due to the chemical reactions. PBT displayed non- Newtanian fluid behaviour when epoxy resin content was 10wt% or higher. SEM results showed there was no obvious difference between the morphology of PBT/ABS-g-GMA blends when epoxy resin content was low, however, agglomeration of ABS phase took place when epoxy resin content was 10wt% or higher due to the complicated reactions. DSC results showed that the addition of epoxy resin to PBT/ABS-g-GMA blends improved the compatibility according to T m depression criterion and DMA test further testified the improved compatibility. Mechanical tests showed impact strength of 902J/m and yield strength of 42MPa was achieved when 20wt% ABS-g-GMA and 5wt% epoxy resin were used, which displayed supper-toughness and much stiffer properties.

In this study, PPS blended with as high as 50 wt% carbon fiber were injection molded. Effects of molding conditions as well as the melt flow condition parallel and perpendicular to fluid channel on the surface conductivity was investigated. It was found that mold temperature affects the surface conductivity of molded parts significantly. Using a variable mold temperature control system based on electromagnetic induction heating, the conductivity of the molded part increase by about 152% when the peak mold temperature increases from 120 °C to 210 °C. The channel layout also helps the fiber to orient more randomly leading to an increase in the conductivity. The channel design parallel to melt flow increases the conductivity by 152% and when it is perpendicular to melt flow, the conductivity increases by 95%. Channel layout perpendicular to melt flow direction provides more influence on the fiber reorientation than that of the parallel design.

This paper reports the thermotropic behaviour of various side-chain liquid crystalline (LC) networks and gels of poly[n-(4’-cyanophenyl-4’’-phenoxy)alkyl acrylate]. Increasing the aliphatic spacer length tend to increase the melting temperature of the pure LC polymers. On the other hand, increasing the crosslinking density lead to a decrease and broadening of the melting transition temperature. Swelling of a liquid crystalline elastomer in a low molar weight liquid crystal (LMWLC) leads to the formation of a LC gel, with thermotropic properties drastically different from the original LC polymers and solvents. The thermotropic behaviour of such an LC gel is determined by several parameters, such as the concentration of LMWLC inside the gel and the compatibility between the two types of mesogens.

The objective of this work was to synthesize boron incorporated PVA/Zinc acetate nano precursor composite polymer fibers using electrospinning technique. Produced fibers, are useful reagents in organic synthesis of zinc oxide nano structures which have gained wide interest because of their potential applications in the fabrication of microelectronic devices. Boron incorporated PVA/Zinc acetate not only improve the electrical properties of ZnO films but also has an influence on the crystal structure of ZnO films. The fibers were measured and characterized by conductiometer (with four-point probe), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The formation of boron incorporated PVA/Zinc acetate hybrid polymer was confirmed by FT-IR spectra. SEM micrographs clearly reveal that there are random-growth oriented fibers on aluminum foil with diameters ranging from 0.5 to 1 μm. According to the TGA analysis decomposition of zinc acetate from the PVA chain was observed around 273 °C, 368 °C and 447 °C. Boron incorporated PVA/Zinc acetate nano composite polymer fibers have been successfully synthesized for the first time using electrospinning technique and characterized in detail as precursor material for ZnO. Electrospinning process has been a widely used, simple and versatile method and in future may be used for large-scale preparation of nanofibers of ZnO.

A series of high clay content Laponite XLS/poly (N-isopropylacrylamide) (PNIPAAm) nanocomposite hydrogels (S-N gels) have been successfully prepared by in-situ ultraviolet (UV) initiated polymerization. The effects of post treatment with HCl solution on swelling/deswelling behaviour of the S-N gels have been investigated in detail. The results indicate that the Laponite XLS/PNIPAAm nanocomposite hydrogels with HCl solution post treatment (S-N-H gels) exhibit great swelling ratio and rapid deswelling response rate; much higher and faster than other reported clay/PNIPAAm nanocomposite hydrogels.

A flexible fluid pump made of magnetic composite gels has been developed. The magnetic composite gel was sodium alginate or poly(vinyl alcohol) gel in which barium ferrite particles were dispersed. The pump consisted of a magnetic gel-rotor and a driving magnet. The rotor demonstrated the rotational motion in response to a rotational magnetic field generated by the driving magnet. The gel-rotor had the shape of a screw so as to deliver water efficiently. The diameter of the rotor was varied from 3.8 to 5.5 mm and the diameter of the tube for delivering water was kept as 6 mm. Flow rates pumped by the rotor increased with increasing the diameter, length, and rotation speeds of the rotor. The maximum flow rate of 34 ml/min was achieved when the rotation speeds was 5000 rpm. The rotor with a diameter of 300 μm was also successfully synthesized, however the rotor did not deliver water in a microtube with a diameter of 500 μm. Processing of the gel-rotor, and the efficiency of the water delivery are presented.

In this paper a synthesis method for low molecular weight poly(orthoesters) with photo crosslinkable methacrylate endgroups is presented. Using this procedure, the molecular weight could be controlled and the desired endgroup functionality was introduced in a single reaction step. The detailed characterization of the molecular structure of bismethacrylate endcapped poly(ortho-esters) using NMR affords a re-evaluation of previous assignments reported for similar poly(ortho-ester) polymers. In addition, the use of diffusion filtered 1D 1 H NMR spectroscopy as a simple but effective analysis tool that allows to distinguish resonance contributions from impurities and low molecular weight compounds, most probably the result of degradation, from those of the full size polymer, is demonstrated.

A simple analytic expression for the first cumulant of the dynamic structure factor of a polymer coil in the Rouse model is derived. The obtained formula is exact within the usual assumption of the continuum distribution of beads along the chain. It reflects the contributions to the scattering of light or neutrons from both the internal motion of the polymer and its diffusion, and is valid in the whole region of the wave-vector change at the scattering.

The swelling behavior of hydroxyethyl cellulose-acrylamide hydrogels at different pH and temperatures was studied. The absorption increased for the first 12 hours and then decreased. Several hydroxyethyl cellulose-acrylamide ratios were studied. Increasing hydroxyethyl cellulose amount decreased swelling, indicating that swelling was affected by increase in crosslinking. Three different levels of crosslinking agent were studied. Hydrogels exhibited a thermal and pH sensitive behaviour. Highest swelling capacity was found at pH 7.0 and 30 °C. All samples were characterized by means of infrared spectroscopy (FTIR). Characteristic absorbance peaks for both materials were found, showing the presence of hydroxyethyl cellulose and acrylamide on hydrogel.

Carboxylated styrene- butadiene rubber (XSBR)/clay nanocomposites were prepared by mixing the XSBR latex with aqueous clay dispersion and cocoagulating the mixture. TEM and XRD were applied to characterize the structure of nanocomposites. Fully exfoliated structure was observed for the nanocomposites containing equal to or less than 10 phr (weight parts per hundred) clay. With increasing the clay content to 20 phr, both non-exfoliated (stacked layers) and exfoliated structures can be observed simultaneously in the nanocomposites. The results of mechanical tests on the vulcanized clay-free XSBR and XSBR/clay nanocomposites showed that the nanocomposites present better mechanical properties than clay-free XSBR vulcanizate. Furthermore, modulus, tensile strength, tensile strain at break and hardness (shore A) increased with increasing the clay content, indicating the nanoreinforcement effect of clay on the mechanical properties of XSBR/ clay nanocomposites.

A novel poly(amido amine) with methoxy carbonyl groups, high charge density and broad nitrogen profile, was synthesized from tetraethylene pentamine (TEPA) and methyl acrylate (MA), and named as PTMA. During synthesis, on one hand, double bond of MA was added with amino group of TEPA by Michael addition reaction and, on the other hand, methoxy carbonyl group of MA was nucleophilicly substituted by amino group of TEPA. There are primary, secondary, tertiary amines and amide groups in PTMA molecule. Acid base titration indicated that the polymer was protonated in the range of both pH 5.0 to pH 7.4 and pH 7.4 to pH 11, which is indicative of not only good self-assembling capability with polyanion but also desirable proton sponge effect as shown by polyethylenimine (PEI). In aqueous solution, PTMA self-assembled with weak anionic polymer, poly(acrylic acid) (PAA), to form nanoparticles. The particle size first increased and then decreased with increasing mass ratio of PTMA to PAA, which is defined as θ. At all examined θ values, self-assembling particles with diameter less than 200 nm were obtained. The UV-Vis absorbance curve of self-assembling complex solution at first day overlapped with that at seventh day, indicating that self-assembling particles were stable.

In order to enhance oil recovery in high-temperature and high-salinity oil reservoirs, the copolymeric microspheres containing acrylamide (AM), acrylonitrile (AN) and AMPS was synthesized by inverse suspension polymerization. The copolymeric microsphere was very uniform and the size could be changed according to the condition of polymerization. The lab-scale studies showed that the copolymeric microsphere exhibit good salt-tolerance and thermal-stability when immersed in 20×10 5 mg/L NaCl(or KCl) solution, 7500 mg/L CaCl 2 (or MgCl 2 ) solution or 2000 mg/L FeCl 3 solution, respectively. The copolymeric microsphere showed satisfactory absorbency rates. The sand-pipes experiments confirmed that the average toughness index was 1.059. It could enhance the oil recovery by about 3% compared with the corresponding irregular copolymeric particle.