Abstract
A detailed, comprehensive mathematical model for bulk polymerization of styrene using multifunctional initiators – both linear and cyclic – in a batch reactor was developed. The model is based on a kinetic mechanism that considers thermal initiation and chemical initiation by sequential decomposition of labile groups, propagation, transfer to monomer, termination by combination and re-initiation reactions due to undecomposed labile groups. The model predicts the evolution of global reaction variables (e.g, concentration of reagents, products, radical species and labile groups) as well as the evolution of the detailed complete polymer molecular weight distributions, with polymer species characterized by chain length and number of undecomposed labile groups. The mathematical model was adjusted and validated using experimental data for various peroxide-type multifunctional initiators: diethyl ketone triperoxide (DEKTP, cyclic trifunctional), pinacolone diperoxide (PDP, cyclic bifunctional) and 1,1-bis(tert-butylperoxy)cyclohexane (L331, linear bifunctional). The model very adequately predicts polymerization rates and complete molecular weight distributions. The model is used to theoretically evaluate the influence of initiator structure and functionality as well as reaction conditions.
Funding statement: Funding: Consejo Nacional de Investigaciones Científicas y Técnicas (Grant/Award Number: “PICT 2011-1254”).
Appendix A: Basic module
Balances for the non-polymeric reagents and products
Multifunctional Initiators
Monomer
Assuming the “long chain approximation” (by which propagation is the only monomer-consuming reaction):
where
represent the total concentrations of mono- and diradicals respectively.
Radical species ( i = 0 , 1 , . . . n = 2 , 3 , . . . )
Consider the mass balances of all free radical appearing in the global kinetics. Such balances provide:
Where
Where
In eq. (12),
Adding this probability over all is and ns, the following can be proved:
where
From eqs (9) and (10), the total concentration of diradicals may be obtained:
From eqs (11) and (12) and considering eq. (13), the total concentration of monoradicals may be obtained:
The total radicals are calculated as
Peroxide groups
The total concentration of peroxide groups is
with
Peroxide groups are consumed only by decomposition reactions. Therefore, it can be written
Using this result and eq. (29), the molar concentration of undecomposed peroxide groups accumulated in the polymer can be calculated from the difference
Conversion and volume
Monomer conversion can be calculated from
where the superscript “0” indicates initial conditions.
The evolution of the reaction volume V is obtained from
with
Where
Equations (1)–(4), (7), (8), and (20) to (22) are solved simultaneously to find the evolution of species
Appendix B: Moments module
Distribution moments equations
Define the kth moment of the distribution of diradicals (
The evolution of the 0th, 1st and 2nd moments of the distributions of diradicals, monoradicals and polymer species are written:
The average molecular weights and polydispersity can then be calculated from
Appendix C: Distributions module
Radical species ( i = 0 , 1 , . . . n = 2 , 3 , . . . )
Consider eqs (10) and (12). Assuming pseudosteady-state, all time derivatives may be set to zero and the following recurrence formulas can be obtained:
Polystyrene species ( i = 0 , 1 , . . . n = 2 , 3 , . . . )
The mass balances for the PS species provide
In order to account for the generation of monoradicals from random scission polymer chains by sequential decomposition of peroxide groups within the chains, consider a polymer chain with length n and i peroxide groups, all of which have the same thermal stability.
Let m be a uniformly distributed random variable whose value ranges 1 from 1 to n–1. The polymer chain may form 2 monoradicals, one with length m, and the other one with length n-m. These chains will have i–j and j–1 undecomposed peroxide groups respectively. If the peroxide groups are assumed to be uniformly distributed within the polymer chains in the course of polymerization, the following relation must hold:
Therefore,
where the brackets indicate the integer part of the expression.
The scission has then generated two monoradicals, one with length m and i-j peroxide groups, the other one with length n-m and j–1 peroxide groups.
Note that this chain scission algorithm can be modified for specific cases. For example, in the case of a linear bifunctional initiator, since all peroxide groups are located at a chain end, m=1 for every scission.
The Number Chain Length Distribution (NCLD) for the PS species is
found by integrating eq. (41) with eqs (39) and (40) using also eqs (9) and (11) to obtain expressions for species
The concentration of the total PS species characterized by the number of undecomposed peroxide groups can be calculated with
The NCLD for the total polymer, characterized by chain length, can be calculated using
The total moles of PS are
To obtain the corresponding weight Chain Length Distribution (WCLD), multiply the NCLD by
The mass of PS can then be calculated as
The average molecular weights and polydispersity can then be calculated from
References
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©2016 by De Gruyter
Artikel in diesem Heft
- Frontmatter
- Review
- Novel Membrane Reactor Concepts for Hydrogen Production from Hydrocarbons: A Review
- Research Articles
- Modeling and Simulation Study of an Industrial Radial Moving Bed Reactor for Propane Dehydrogenation Process
- Oxidative Degradation of Methylene Blue in Aqueous Medium Catalyzed by Lab Prepared Nickel Hydroxide
- CFD Modelling of a Hollow Fibre Membrane for CO2 Removal by Aqueous Amine Solutions of MEA, DEA and MDEA
- Performance Study of a Thermally Double Coupled Multi-Tubular Reactor by Considering the Effect of Flow Type Patterns
- Radiative Three-Dimensional Flow with Chemical Reaction
- Three-Phase Model of a Fluidized-Bed Catalytic Reactor for Polyethylene Synthesis
- Study on the Effect of Nickel Doping on Mo-Bi Based Catalyst for Selective Oxidation of Isobutene to Methacrolein
- DM Water Plant Sedimentation as a Cheap and Waste Source of Catalyst for Biodiesel Production
- Recovery of Biogas from Meat Industry Wastewater Using Continuously Stirred Tank Reactor (CSTR): Modeling and Optimization
- Comparison of CFD Simulation and Simplified Modeling of a Fluidized Bed CO2 Capture Reactor
- Kinetic Study for Platinum Extraction from Spent Catalyst in Cyanide Solution at High Temperatures
- Hydroisomerization of Biomass Derived n-Hexadecane Towards Diesel Pool: Effect of Selective Removal External Surface Sites from Pt/ZSM-22
- Heat Flux and Variable Thermal Conductivity Effects on Casson Flow and Heat Transfer due to an Exponentially Stretching Sheet with Viscous Dissipation and Heat Generation
- Optimization of Nickel Chemical Extraction from Hazardous Residue
- Green Approach for Biodiesel Production from Jojoba Oil Supported by Process Modeling and Simulation
- Differentiating Process Performance of Various Coagulants in Removal of Congo red and Orange G Dyes
- CFD Simulation of Hydrodynamic of a Bubble Column Reactor Operating in Churn-Turbulent Regime and Effect of Gas Inlet Distribution on System Characteristics
- Transformation of Phenolic Compounds by Fe(III) in the Aqueous Solution in Dark and Under Irradiation
- Transient Predictive Model for Dynamic Analysis, Kinetic Study, and Reactor Design of Triglycerides Transesterification to Biodiesel
- Screening of Alternative Carbon Sources for Recombinant Protein Production in Pichia pastoris
- Optimization of a Large Scale Industrial Reactor Towards Tailor Made Polymers Using Genetic Algorithm
- Model of Reactive Transport within a Light Photocatalytic Textile
- Preparation of Chitosan based Nanofibers: Optimization and Modeling
- Adsorption of As (III) on Iron Coated Quartz Sand: Influence of Temperature on the Equilibrium Isotherm, Thermodynamics and Isosteric Heat of Adsorption Analysis
- Resistance Characteristics of Coal Slime in Pipe Flow at High Pressure
- Activity Comparison of Acidic Resins in the Production of Valuable Glycerol Acetates
- Bulk Polymerization of Styrene using Multifunctional Initiators in a Batch Reactor: A Comprehensive Mathematical Model
- An Effective Reaction Rate Model for Gas-Solid Reactions with High Intra-Particle Diffusion Resistance
- Heart-Like Micro-Flow Mixer
- Hydrogen Production by Hydrolysis of NaBH4 with Cr-Ni-W-B Catalyst: Effects of Cold Plasma and Chromium Content
- Prediction of Reactivity Ratios in Free Radical Copolymerization from Monomer Resonance–Polarity (Q–e) Parameters: Genetic Programming-Based Models
- Steady-State Modeling of Pt-Catalyzed H2 Combustion in a Monolithic Reactor: From Micro- to Macro-kinetics
- Premixed Methanol–Air Combustion Characteristics in a Mini-scale Catalytic Combustor
- Kinetic Modeling of VOC Photocatalytic Degradation Using a Process at Different Reactor Configurations and Scales
- Improvement of Activated Sludge Process Using a Nonlinear PI Controller Design via Adaptive Gain
- Modeling and Simulation of a Pilot-Scale Bubbling Fluidized Bed Gasifier for the Gasification of High Ash Indian Coal Using Eulerian Granular Approach
- Performance of a Catalytic Gas–Solid Fluidized Bed Reactor in the Presence of Interparticle Forces
- Mathematical Modeling of Biodiesel Production under Intense Agitation
- Extended Aeration Activated Sludge Reactor (EAASR) for Removal of Nitrobenzene: Air Stripped or Biologically Removed?
- CFD Modeling of Algae Flash Pyrolysis in the Batch Fluidized Bed Reactor Including Heat Carrier Particles
- A Robust Extended State Observer for the Estimation of Concentration and Kinetics in a CSTR
- Dynamic Modeling of CATOFIN® Fixed-Bed Iso-Butane Dehydrogenation Reactor for Operational Optimization
- Effect of Biomass Compositions on Combustion Kinetic Parameters using Response Surface Methodology
- Short Communications
- Discussions on Particle Flux Measurement in Gas-Solids Risers
- Use of New Regeneration Processes for Thermolabile Amines
- Oxidative-Extractive Desulfurization of Liquid Fuel by Dimethyl Sulfoxide and ZnCl2 Based Ionic Liquid
- Corrigendum
- Corrigendum to: Performance Analysis of Immobilized Enzyme Semifluidised Bed Bioreactors
Artikel in diesem Heft
- Frontmatter
- Review
- Novel Membrane Reactor Concepts for Hydrogen Production from Hydrocarbons: A Review
- Research Articles
- Modeling and Simulation Study of an Industrial Radial Moving Bed Reactor for Propane Dehydrogenation Process
- Oxidative Degradation of Methylene Blue in Aqueous Medium Catalyzed by Lab Prepared Nickel Hydroxide
- CFD Modelling of a Hollow Fibre Membrane for CO2 Removal by Aqueous Amine Solutions of MEA, DEA and MDEA
- Performance Study of a Thermally Double Coupled Multi-Tubular Reactor by Considering the Effect of Flow Type Patterns
- Radiative Three-Dimensional Flow with Chemical Reaction
- Three-Phase Model of a Fluidized-Bed Catalytic Reactor for Polyethylene Synthesis
- Study on the Effect of Nickel Doping on Mo-Bi Based Catalyst for Selective Oxidation of Isobutene to Methacrolein
- DM Water Plant Sedimentation as a Cheap and Waste Source of Catalyst for Biodiesel Production
- Recovery of Biogas from Meat Industry Wastewater Using Continuously Stirred Tank Reactor (CSTR): Modeling and Optimization
- Comparison of CFD Simulation and Simplified Modeling of a Fluidized Bed CO2 Capture Reactor
- Kinetic Study for Platinum Extraction from Spent Catalyst in Cyanide Solution at High Temperatures
- Hydroisomerization of Biomass Derived n-Hexadecane Towards Diesel Pool: Effect of Selective Removal External Surface Sites from Pt/ZSM-22
- Heat Flux and Variable Thermal Conductivity Effects on Casson Flow and Heat Transfer due to an Exponentially Stretching Sheet with Viscous Dissipation and Heat Generation
- Optimization of Nickel Chemical Extraction from Hazardous Residue
- Green Approach for Biodiesel Production from Jojoba Oil Supported by Process Modeling and Simulation
- Differentiating Process Performance of Various Coagulants in Removal of Congo red and Orange G Dyes
- CFD Simulation of Hydrodynamic of a Bubble Column Reactor Operating in Churn-Turbulent Regime and Effect of Gas Inlet Distribution on System Characteristics
- Transformation of Phenolic Compounds by Fe(III) in the Aqueous Solution in Dark and Under Irradiation
- Transient Predictive Model for Dynamic Analysis, Kinetic Study, and Reactor Design of Triglycerides Transesterification to Biodiesel
- Screening of Alternative Carbon Sources for Recombinant Protein Production in Pichia pastoris
- Optimization of a Large Scale Industrial Reactor Towards Tailor Made Polymers Using Genetic Algorithm
- Model of Reactive Transport within a Light Photocatalytic Textile
- Preparation of Chitosan based Nanofibers: Optimization and Modeling
- Adsorption of As (III) on Iron Coated Quartz Sand: Influence of Temperature on the Equilibrium Isotherm, Thermodynamics and Isosteric Heat of Adsorption Analysis
- Resistance Characteristics of Coal Slime in Pipe Flow at High Pressure
- Activity Comparison of Acidic Resins in the Production of Valuable Glycerol Acetates
- Bulk Polymerization of Styrene using Multifunctional Initiators in a Batch Reactor: A Comprehensive Mathematical Model
- An Effective Reaction Rate Model for Gas-Solid Reactions with High Intra-Particle Diffusion Resistance
- Heart-Like Micro-Flow Mixer
- Hydrogen Production by Hydrolysis of NaBH4 with Cr-Ni-W-B Catalyst: Effects of Cold Plasma and Chromium Content
- Prediction of Reactivity Ratios in Free Radical Copolymerization from Monomer Resonance–Polarity (Q–e) Parameters: Genetic Programming-Based Models
- Steady-State Modeling of Pt-Catalyzed H2 Combustion in a Monolithic Reactor: From Micro- to Macro-kinetics
- Premixed Methanol–Air Combustion Characteristics in a Mini-scale Catalytic Combustor
- Kinetic Modeling of VOC Photocatalytic Degradation Using a Process at Different Reactor Configurations and Scales
- Improvement of Activated Sludge Process Using a Nonlinear PI Controller Design via Adaptive Gain
- Modeling and Simulation of a Pilot-Scale Bubbling Fluidized Bed Gasifier for the Gasification of High Ash Indian Coal Using Eulerian Granular Approach
- Performance of a Catalytic Gas–Solid Fluidized Bed Reactor in the Presence of Interparticle Forces
- Mathematical Modeling of Biodiesel Production under Intense Agitation
- Extended Aeration Activated Sludge Reactor (EAASR) for Removal of Nitrobenzene: Air Stripped or Biologically Removed?
- CFD Modeling of Algae Flash Pyrolysis in the Batch Fluidized Bed Reactor Including Heat Carrier Particles
- A Robust Extended State Observer for the Estimation of Concentration and Kinetics in a CSTR
- Dynamic Modeling of CATOFIN® Fixed-Bed Iso-Butane Dehydrogenation Reactor for Operational Optimization
- Effect of Biomass Compositions on Combustion Kinetic Parameters using Response Surface Methodology
- Short Communications
- Discussions on Particle Flux Measurement in Gas-Solids Risers
- Use of New Regeneration Processes for Thermolabile Amines
- Oxidative-Extractive Desulfurization of Liquid Fuel by Dimethyl Sulfoxide and ZnCl2 Based Ionic Liquid
- Corrigendum
- Corrigendum to: Performance Analysis of Immobilized Enzyme Semifluidised Bed Bioreactors