Mathematical Modeling and Simulation of Vinylidene Fluoride Emulsion Polymerization

In the present study a comprehensive model is employed to describe the dynamic behavior of an industrial scale reactor for the emulsion polymerization of vinylidene fluoride (VDF) under different initiator and chain transfer agent (CTA) addition policies. A comprehensive kinetic model combined with a thermodynamic and a particle population model were simultaneously solved to calculate the VDF addition rate, reactor pressure, molecular weight properties, and the particle size distribution of polyvinylidene fluoride produced in a semibatch emulsion polymerization reactor. The proposed emulsion polymerization model takes into account the gas liquid equilibrium of VDF to determine the aqueous phase VDF concentration and the changes in operating pressure. The effects of particle crystallinity on radical entry and coagulation rate were also considered. The computational model results (cumulative monomer feed and feed rate, reactor pressure, molecular weights, and particle size distribution) are found to be in agreement with available experimental data.