MINIEMULSION POLYMERIZATION - AN APPROACH TO CONTROL COPOLYMER COMPOSITION

The copolymerization of vinyl acetate (VAc) and vinyl 2-ethylhexanoate (V2EH) via miniemulsion polymerization is being investigated with the goal of better copolymer composition control. The reaction kinetics and final particle sizes were compared for homopolymerizations and copolymerizations of the two monomers. Enhanced polymerization rates were seen for the miniemulsion polymerizations over their conventional counterparts despite a decreased number of particles. This was attributed to the influence of the reactive surfactant sodium dodecyl allyl sulfosuccinate and low water solubility of the V2EH monomer. Increased nucleation of miniemulsion droplets was sought by incorporation of small amounts of polymer into the droplets. This was first shown to be effective for styrene miniemulsion polymerizations and was subsequently successfully extended to the VAc/V2EH system.