Population Balance PSD Model for Emulsion Polymerization with Steric Stabilizers

摘要

A detailed population balance model is developed for the particle-size distribution (PSD) in the emulsion copolymerization of vinyl acetate and butyl acrylate, with nonionic poly(ethylene oxide) surfactants and a redox initiator pair (t-butyl hydrogen peroxide and sodium formaldehyde sulphoxylate). The model accounts for the effects of the nucleations, growth, and coagulation events on the evolution of the P9SD. The study addresses the modeling of the coagulation kernel (time-varying and size-dependent intrinsic coagulatio rate) under nonionic surfactants. The coagulation-inclusive model results show significant differences from the results generated by a coagulation-free model (even under low solids conditions). More importantly, the coagulation-inclusive modelo predicts to a reasonable accuracy the experimental data on the full PSD.