EMULSION TERPOLYMERIZATION OF BUTYL ACRYLATE METHYL-METHACRYLATE VINYL-ACETATE - EXPERIMENTAL RESULTS

A systematic study of the terpolymerization of butyl acrylate/methyl m ethacrylate/vinyl acetate (BA/MMA/VAc) was conducted. In this stage of the study, batch emulsion terpolymerizations were performed in a 5 L stainless steel pilot plant reactor. The experiments were designed usi ng a Bayesian (optimal) technique. The polymers produced were characte rized for conversion, composition, molecular weight, and particle size . Conversion, terpolymer composition, number- and weight-average molec ular weight, and average particle size results are discussed in light of the influence of seven factors and the interaction of these factors . The factors studied include monomer feed composition, initiator conc entration, chain transfer agent concentration, impurity concentration, initiator type, emulsifier concentration, and temperature. A ''two-st age rate'' phenomenon, similar to that occurring in bulk co- and terpo lymerization and emulsion copolymerization of acrylic/vinyl acetate sy stems was observed in the conversion, composition and molecular weight data. Furthermore, an interesting yet often ignored effect of impurit ies on emulsion polymerization kinetics was explained. (C) 1997 John W iley & Sons, Inc.