| 摘要 |
Copolymerization in aqueous emulsion of ethylene with one or two comonomers having different water solubilities is more efficient when at least two but no more than three comonomer solubility-affecting additives are present in the copolymerization medium, at least one of which increases the solubility in water of one of the comonomers, while at least another one decreases the solubility in water of another comonomer. In this manner, the diffusion rates of comonomers to the copolymerization locus are well controlled; the rate of polymerization often is increased; the concentrations of the comonomers at the copolymerization locus remain constant; and the copolymer composition remains constant. This process improvement can be applied to the copolymerization of many comonomer combinations of great commercial interest, including, for example ethylene/tetrafluoroethylene and ethylene/ethyl acrylate copolymerizations.
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