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The POLYCHAR 16: World Forum on Advanced Materials, organized by the University of Lucknow, was held from 17 to 21 February 2008 in the capital of the state of Uttar Pradesh, India. The annual POLYCHAR conferences have been sponsored by IUPAC for several years and are known for combining the broad field of materials sciences with a clear focus on polymeric materials (the name "POLYCHAR" is derived from the term "polymer characterization"). POLYCHAR 16 was supported by many scientific associations and industries such as IUPAC, Abdus Salam International Center for Theoretical Physics (ICTP) (Trieste, Italy), Indian Space Research Organization (ISRO), Department of Biotechnology (DBT) (India), Council of Scientific and Industrial Research (CSIR) (India), Reliance Industries Ltd. (India), Department of Science and Technology (India), Indian Council for Medical Research (ICMR), Indian National Science Academy (INSA), Uttar Pradesh Council of Science and Technology (UPCST) (India), Lucknow Chapter, Materials Research Society of India (MRSI), and University of Lucknow. As in past years, POLYCHAR puts emphasis on the quality of research presented - in contrast to maximizing the number of participants. The areas covered include nanomaterials and smart materials; natural and biodegradable materials and recycling; materials synthesis; polymers for energy; rheology, solutions, and processing; mechanical properties and performance; characterization and structure-property relationships; biomaterials and tissue engineering; dielectric and electrical properties; surfaces, interfaces, and tribology; and predictive methods. Symptomatically, the number of papers on "green" science was higher than at POLYCHAR 15 last year in Búzios, Rio de Janeiro. There were a total of 292 registered participants from 35 countries (Austria, Bangladesh, Belgium, Brazil, China, Colombia, Croatia, Czech Republic, Egypt, Fiji, UK, France, Germany, India, Iran, Israel, Japan, Korea, Kuwait, Mauritius, Malaysia, Mexico, Nepal, Netherlands, New Zealand, Poland, Portugal, Russia, Sri Lanka, Slovakia, South Africa, Ukraine, USA, Uzbekistan, and Venezuela). This reflects the philosophy of POLYCHAR to provide an international forum to encourage young scientists and advanced students to present their scientific work and give them the opportunity to meet with colleagues and well-known scientists to discuss their results, exchange experiences, and make new contacts, in particular, international ones. Many industrial contacts and much international cooperation with exchange of students and scientists have resulted from this and earlier POLYCHAR meetings. This conference volume represents only a small fraction of the multitude of contributions from different parts of materials science - 48 oral contributions and 170 posters. Many of the contributions have review character, some represent excellent original contributions. Only a small number could be selected for this volume because of the limited space that is available. All this was possible with the sponsorship of IUPAC. Highlights of the conference were the Paul J. Flory Research Award (ex aequo) to Prof. Jiasong He, Institute of Chemistry, Chinese Academy of Sciences, Beijing, China; the International Materials Research Award to Dr. Rameshvar Adhikari, Tribhuvan University, Katmandu, Nepal; and numerous awards for young scientists and students, including the IUPAC Poster Award. Special Prof. Brar's 60th Birthday Celebration Awards were given to IUPAC poster prize winners. The next POLYCHAR will be hosted by Jean-Marc Saiter, University of Rouen, Rouen, France in April 2009. Poonam Tandon Conference Executive Secretary and Co-editor

High-resolution NMR spectroscopy is the most versatile, reliable, and generally acceptable technique for the determination of the microstructure of polymers. 2D NMR techniques, along with 1D NMR, have more potential to study absolute configurational assignments and sequence distribution of copolymers. Physical and chemical properties of polymers are influenced fundamentally by their microstructure. We discuss the detailed microstructure analysis of a large number of homopolymers, copolymers, and terpolymers. 2D NMR study of poly(methyl methacrylate) (PMMA), poly(methyl acrylate) (PMA), and poly(methacrylonitrile) (PMAN) is discussed in this article. In addition to homopolymers, 2D heteronuclear single-quantum coherence (HSQC), total correlation spectroscopy (TOCSY), and heteronuclear multiple-bond correlation (HMBC) study of different copolymers such as poly(methyl methacrylate- co -methyl acrylate), poly(styrene- co -methyl methacrylate), and poly(methyl methacrylate- co -methacrylonitrile) have also been reported here. This in turn helps in microstructural analysis of terpolymers such as poly(methacrylonitrile- co -styrene- co -methyl methacrylate), poly(acrylonitrile- co -methyl methacrylate- co -methyl acrylate), and poly(ethylene- co -vinyl acetate- co -carbon monoxide).

The prediction of long-term performance from short-term tests is the bottom line of polymer science and engineering for users of polymer-based materials (PBMs) - which means for scientists, engineers, and laymen, or, literally, for everybody. Methods of prediction of mechanical properties (creep, stress relaxation, dynamic mechanical behavior, tension, etc.) based on the chain relaxation capability (CRC), the stress-time and temperature-time correspondence principles are presented. The methods can be applied even to small amounts of experimental data (2 or 3 isotherms or 2 or 3 stress levels) and can produce much better results than the still used 1955 Williams-Landel-Ferry (WLF) equation. Successful applications of the CRC approach include multiphase systems, including polymer liquid crystal (PLC) copolymers. An extension to the tribological properties of PBMs (in particular, scratch healing) is outlined. A quantitative definition of materials brittleness was formulated in 2006; it is connected to results in both the mechanics and tribology of PBMs.

A novel π-conjugated organoboron polymer with a chiral side chain was prepared by way of hydroboration polymerization between an optically active diyne monomer and triisopropylphenylborane. The achiral analog of this organoboron polymer was also prepared as reference material. Optical properties and optical activity were investigated by UV-vis absorption, fluorescence emission, and circular dichroism (CD) spectroscopy. Concentration dependence and the influence of solvent effects upon chiroptical activity are described.

The interaction of water-soluble polymer conjugates of the anticancer agent paclitaxel and albumin as model protein has been investigated using fluorescence spectroscopy and NMR. Drugs and drug conjugates can enter the hydrophobic core of albumin; the kinetics of the interaction with the fluorophore, however, differs. Given the information about the steric situation of the formed complexes, some aspects of molecular engineering of the drug are discussed.

The fundamental features and industrial applications of the direct fluorination of polymers are reviewed. Direct fluorination of polymers (i.e., treatment of a polymer surface with gaseous fluorine mixtures) proceeds spontaneously at room temperature and is a surface modification process. More than 25 polymers have been studied with the aid of a variety of analytical and spectroscopic techniques. The fundamental features of the direct fluorination, such as influence of treatment conditions (composition of the fluorinating mixture, fluorine partial pressure, temperature, and fluorination duration) on the rate of formation, chemical composition, density, refraction index, and surface energy of the fluorinated layer, kinetics of formation of radicals during fluorination and their termination, texture of fluorinated layer, etc. were studied. It was demonstrated experimentally that direct fluorination can be effectively used to enhance commercial properties of polymer articles, such as barrier properties of polymer vessels, bottles, and packaging films and envelopes; gas-separation properties of polymer membranes; adhesion and printability properties of polymer articles; and mechanical properties of polymer-based composites.

The science of polymers, more specifically, synthesis, characterization, and physicochemical properties in solutions, has wide application in the petroleum industry, which uses polymers as components of fluids or additives to correct problems that affect oil production and/or increase production costs. Polymers are utilized during all phases, from drilling to treatment of oil and water. Research on the synthesis of polymers and their respective characterization aims to develop new molecules, with controlled structures, for various applications, having one or more objectives, namely: (1) to enhance operating efficiency; (2) to reduce costs; and (3) to elucidate mechanisms of action that can help in the development of new technologies. The evaluation of the physicochemical properties of a polymer in solution in many cases permits establishing useful correlations between its properties and performance in a specific application, besides providing insight into the mechanisms inherent in the production system, as is the case of stabilization of asphaltenes. Our research group has applied the knowledge of polymer science to the petroleum industry, focusing on the following functions: viscosification, inhibition of clay swelling, formation of filter cake, drag reduction, divergence, modification of wax crystals, stabilization of asphaltenes, emulsification, demulsification, and cleaning of solids systems contaminated with petroleum, among others.

Superhydrophobicity is dependent on both the surface energy and the texture of the surface. These factors are discussed in terms of a series of electrospun poly(methyl methacrylate)-graft-poly(dimethylsiloxane) (PMMA- g -PDMS) copolymers with different poly(dimethylsiloxane) (PDMS) content. These copolymers are synthesized via conventional free radical copolymerization of methyl methacrylate (MMA) and monomethacryloxypropyl-terminated PDMS macromonomers. It is shown how these copolymers can be electrospun to produce copolymer fibers with diameters in the 100-1000 nm range. The effect of the copolymer composition (and hence the surface energy) and the electrospinning tip-to-collector distance (TCD) on the fiber morphology is discussed. The surfaces produced by the electrospinning process show superhydrophobic properties where the preferential surface segregation of the PDMS component is combined with the roughness of the fiber surface. The surface energy of the fibers is varied by variation of the PDMS content in the copolymers as well as by post-spinning modification with corona discharge. The hydrophobicity of the surfaces shows a greater dependence on the PDMS content than on the average fiber diameter. After exposure of these fiber surfaces to corona discharge, the initial superhydrophobic surfaces become easily wettable despite the fact that much of the surface roughness is maintained after exposure. The samples show the phenomena of hydrophobocity recovery after corona exposure. The rate and extent of this recovery depends on the PDMS content and the corona exposure time. Despite the recovery, scanning electron microscopy (SEM), swelling measurements, and confocal Raman spectroscopy show that permanent surface changes have taken place. The surfaces do not recover to their original superhydrophobic state.

Gelation mechanisms of ultra-high-molecular-weight polyethylene (UHMWPE) in dispersion solutions containing multiwall carbon nanotubes (MWNTs) were investigated in terms of liquid-liquid phase separation mechanisms. When an incident beam of He-Ne gas laser was directed to the dispersion solution quenched to a desired temperature, the logarithm of scattered intensity increased linearly with elapsing time and tended to deviate from this linear relationship. The two different increasing behaviors of the scattered intensity were termed as initial and latter stages, respectively, of the phase separation. The linear increase in logarithmic light-scattered intensity was analyzed within the framework of the linear theory of spinodal decomposition in terms of the viewpoint that the quenched solution becomes thermodynamically unstable and tends to incur phase separation to resolve the unstable state. The growth rate of the concentration fluctuation of neat UHMWPE solution (without MWNTs) calculated from the slope of linear increase was faster than that of the dispersion solution. In spite of the rapid growth rate, however, the gelation time of the dispersion solution was much shorter than that of the neat UHMWPE solution and the gelation and quasi-spinodal temperatures were slightly higher. These phenomena were in contradiction with the result of the concentration fluctuation. This contradiction was thought to be due to the fact that diffused UHMWPE chains in the dispersion solution were gelled easily on the MWNT surface rather than the gelation by self-coagulation.

Polysaccharides are abundantly available from farm, forest, and microbial resources. They are used in myriad applications. It has been established in the authors' laboratory that their performance is enhanced considerably on purification, grafting by polyacrylamide (PAM), and subsequent hydrolysis as well as cationization. The most significant performance is enhanced in flocculation where it has been found that the modified polysaccharides outperform existing flocculants in national and international markets. Similar effects are observed in their performance in turbulent drag reduction (DR), percolation, and rheology. The present article outlines the details of materials, mechanisms, and practical applications of these novel materials.

Polymers are an important class of materials, and their conformation dictates their dynamical, thermodynamical, and hydrodynamical behavior. Several spectroscopic and other techniques have been employed to characterize their conformation. However, little use has been made of group-theoretical techniques except in the classification of symmetry species. In the present review, an attempt has been made to correlate normal modes and their dispersion profiles with the conformation of the polymeric systems. This has been attempted in the case of 2-, 3-, 4-fold and α-helical polymers.