ASPECTS OF COAGULATION DURING EMULSION POLYMERIZATION OF STYRENE AND VINYL-ACETATE

The influence of recipe and process conditions on the coagulation beha vior of polystyrene (PS) and polyvinyl acetate (PVAc) latices has been studied. Seeded batch experiments reveal a significant influence of e lectrolyte concentration on the coagulation behavior of both PS and PV Ac latices. Within the experimental error, no dependency of the coagul ation behavior on process conditions, in terms of energy dissipation, reactor scale, impeller type, and impeller diameter, has been observed for the reactor scales investigated. These results indicate that intr insic chemical influences such as electrolyte concentration dominate t he coagulation behavior during emulsion polymerization and also in the absence of polymerization over the process conditions. (C) 1998 John Wiley & Sons, Inc.