| 摘要 |
<p>Elastomeric vinyl acetate-ethylene copolymers having high Mooney viscosity and low gel content are prepared by the process which comprises: a) copolymerization from about 40% to about 70% by weight of vinyl acetate monomer with from about 60% to about 30% by weight of ethylene monomer in an aqueous emulsion reaction medium to provide a latex, the reaction medium for vinyl acetate-ethylene elastomer containing: (i) at least one surface active agent in an amount above about 2.2% by weight of the total monomer. (ii) a polymerization catalyst, and (iii) at least one protective colloid in an amount of less than about one part for each part by weight of total surface active agent, with the total weight of the surface active agent and vinyl acetate being present in the reaction medium at the commencement of copolymerization: and, b) recovering the vinyl acetate-ethylene elastomer from the latex.</p> |
