A systematic approach to the study of multicomponent polymerization kinetics: the butyl acrylate/methyl methacrylate/vinyl acetate example: Bulk (and solution) terpolymerization

摘要

A systematic study of the terpolymerization of butyl acrylate/methyl methacrylate/vinyl acetate (BA/MMA/VAc) is being conducted. In the second stage of this study, bulk (and solution) terpolymerizations of BA/MMA/VAc were performed. The polymers produced were characterized for conversion, composition and molecular weight. The terpolymerizations exhibited behaviour similar to vinyl acetate-containing copolymerizations, that is, a "double gel effect" was observed. During the first period of the reaction the acrylic monomers virtually "copolymerized" and thus the reaction exhibited the characteristics of a "solution" copolymerization of the acrylic monomers with the vinyl acetate acting as the "solvent". Typical "solution" polymerization behaviour, i.e., a dampened autoacceleration or gel effect, was in evidence for this first period of the reaction. After the virtual depletion of the acrylic monomers, the remaining vinyl acetate polymerized and exhibited its own characteristic gel effect. Estimates of the copolymerization reactivity ratios obtained previously were found to accurately predict terpolymer composition up to high conversion levels. Molecular weight results indicated that branched polymers were being produced at high conversions in the bulk experiments.