Modeling of Emulsion Polymerization of Vinyl Chloride

Abstract

A survey of the principles of emulsion polymerization modeling of vinyl chloride is presented. Experimental results and model equations for particle nucleation, particle coalescence, and particle growth are discussed. A mechanism for particle coalescence in the course of polymerization is proposed based on the assumption that radical desorption from a particle is the rate-determining step for coalescence. Equations for the coalescence rate and velocity constant are derived based on this assumption. The resulting population balance equations for describing the change of particle size distribution during emulsion polymerization of vinyl chloride can be applied to different polymerization procedures, e.g., discontinuous, continuous, and seeded polymerizations. Examples of model calculations are given for several polymerization procedures and compared with experimental data.