Simulation styrene polymerization kinetics

In conclusion, we have reviewed how our kinetic model did simulate the experiments for the thermally-initiated styrene polymerization. The results of our kinetic model compared closely with some published isothermal experiments on thermally-initiated styrene and on styrene and MMA using initiators. These experiments and other modeling efforts have provided us with useful guidelines in analyzing more complex systems. With such modeling efforts, we can assess the hazards of a polymer reaction system at various tempera-atures and initiator concentrations by knowing certain physical, chemical and kinetic parameters. 

CUTTER and DREXLER Simulation of Styrene Polymerization Kinetics... 

Butte et al. [1999] carried out experiments for both types of free radical polymerization of styrene and simulated the results using kinetic parameters obtained from the literature after adaptation accounting for their own observations. 

Deady M, Mau AWH, Moad G, Spurling TH. Evaluation of the kinetic-parameters for styrene polymerization and their chain-length dependence by kinetic simulation and pulsed-laser photolysis. Makromol Chem-Macromol Chem Phys 1993 194 1691-1705. 

In this work, a comprehensive kinetic model, suitable for simulation of inilticomponent aiulsion polymerization reactors, is presented A well-mixed, isothermal, batch reactor is considered with illustrative purposes. Typical model outputs are PSD, monomer conversion, multivariate distritution of the i lymer particles in terms of numtoer and type of contained active Chains, and pwlymer ccmposition. Model predictions are compared with experimental data for the ternary system acrylonitrile-styrene-methyl methacrylate. 

Kinetics of initiated radical polymerization of styrene is well studied at the initial stages. At the high-conversion of polymerization the growth of viscosity of media- influences the mechanism and kinetics of process greatly (12),In our research we have attempted to obtain tne empirical dependence of some rate constants of initiated polymerization of styrene on conversion with the aim of using them at mathematical simulation of the process. 

Polymerization reactions require stringent operating conditions for continuous production of quality resins. In this paper the chain-growth polymerization of styrene initiated with n-butyllithium in the presence of a solvent is described. A perfectly mixed isothermal, constant volume reactor is employed. Coupled kinetic relationships descriptive of the initiator, monomer, polystyryl anion and polymer mass concentration are simulated. Trommsdorff effects (1) are incorporated. Controlled variables include number average molecular weight and production rate of total polymer. Manipulated variables are flow rate, input monomer concentration, and input initiator concentration. The... 

Kinetic analyses were done for several copper-catalyzed copolymerizations of MMA/nBMA,263 nBA/ styrene,264 266 and nBA/MMA.267 All these studies show that there were no significant differences in reactivity ratio as well as in monomer sequence between the copper-catalyzed and conventional radical polymerizations. Only a difference was observed in the copolymerizations between MMA and ometh-acryloyl-PMMA macromonomers where the reactivity of the latter is higher in the metal-catalyzed polymerizations.267 However, this can be ascribed not to the different nature of the propagating species but to the difference in the time scale of monomer addition or other factors. Simulation has also been applied for the copolymerization study.268... 

Bentein, L., D hooge, DJI., Reyniers, M.F., Marin, G.B., 2011. Kinetic modeling as a tool to rmderstand and improve the nitroxide mediated polymerization of styrene. Macromol. Theory Simul. 20, 238-265. 

Greszta, D., and Matyjaszewski, K. (1996). Mechanism of controlled/ living radical polymerization of styrene in the presence of nitroxyl radicals. Kinetics and simulations. Macromolecules, 29(24) 7661-7670. 

Chern [42] developed a mechanistic model based on diffusion-controlled reaction mechanisms to predict the kinetics of the semibatch emulsion polymerization of styrene. Reasonable agreement between the model predictions and experimental data available in the literature was achieved. Computer simulation results showed that the polymerization system approaches Smith-Ewart Case 2 kinetics (n = 0.5) when the concentration of monomer in the latex particles is close to the saturation value. By contrast, the polymerization system under the monomer-starved condition is characterized by the diffusion-con-trolled reaction mechanisms (n > 0.5). The author also developed a model to predict the effect of desorption of free radicals out of the latex particles on the kinetics of the semibatch emulsion polymerization of methyl acrylate [43]. The validity of the kinetic model was confirmed by the experimental data for a wide range of monomer feed rates. The desorption rate constant for methyl acrylate at 50°C was determined to be 4 x 10 cm s ... 

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