An object of the present invention is to provide a dispersion assistant that, when used for suspension polymerization of a vinyl-based compound, achieves stable production of a good polymer (vinyl-based resin) without much scale adhesion on the polymerization tank even in the cases where used in a large amount. Provided is a dispersion assistant for suspension polymerization, which comprises a polyvinyl alcohol-based polymer (A) having an acetal group (a) having an olefinic unsaturated double bond, the polymer having a saponification degree of 60 mol% or less.
本发明的目的是提供一种分散助剂,该助剂用于
乙烯基化合物的悬浮聚合时,可稳定地生产出良好的聚合物(
乙烯基树脂),即使在大量使用的情况下,聚合罐上也不会有太多的
水垢附着。本发明提供了一种用于悬浮聚合的分散助剂,它由聚
乙烯醇基聚合物 (A) 组成,该聚合物具有一个具有烯烃不饱和双键的
缩醛基团 (a),该聚合物的皂化度不超过 60 摩尔%。