Modeling and Simulation of Olefin Polymerization at Microstructure Level

A new model based on a combination of the polymeric multigrain and multilayermodels has been developed to predict the polymerization rate, particle growth, morphology,effective parameters on broadening of the molecular weight distribution, number and weightaverage of the molecular weight, isotacticity index and bulk density of polymer. mathematicalcorrelations and the kinetics used in this model are based on the polymeric multigrain and themultilayer models, respectively. in the modeling, multiplicity of active site using different kineticsparameters as well as deactivation of catalyst during the polymerization have been considered,.moreover, it considers mass transfer effects on polymerization characteristics. the effects ofphysico-chemical aspects of catalyst associated with the polymerization in slurry phase are alsoconsidered in this model. in addition, the effects of more important model parameters includingtime step, number of layers and number of active sites on the produced polymer features arereviewed. the model predictions show that propagation rate constant, multiplicity of active site,concentration of any individual active site type, and the initial size of the catalyst particles haveconsiderable effects on the properties of the final polymer. the results obtained from simulationwith this new combined model confirm at least better qualitative prediction of the polymerizationcharacteristics in comparison with simulation results of the multigrain model (mgm) and the twomodels mentioned above.