High Pressure Emulsion and Miniemulsion Copolymerization of Vinyl Acetate and Ethylene

Abstract

Miniemulsion copolymerization in gas-liquid systems such as vinyl acetate-ethylene (VAE) differs from that of conventional VAE emulsion copolymerization. Particle nucleation in miniemulsions is mainly due to the radical entry into the monomer droplets. The objective of this thesis is to study the reaction mechanism of VAE miniemulsion copolymerization, characterize the copolymer formed and compare it to the conventionally and commercially used VAE emulsion copolymer, and highlight any advantages of VAE miniemulsions over normal VAE emulsions. Miniemulsions have shown to be more stable and long-lasting than emulsions in terms of particle size distributions. The amount of ethylene incorporated in the copolymer is higher in the case of miniemulsions as compared to emulsions due to decreased mass transfer limitations of ethylene in the aqueous phase and subsequent incorporation into the VAE copolymer.