Provided is a dispersion stabilizer for suspension polymerization comprising an aqueous emulsion containing a dispersant (A), a dispersoid (B), a graft polymer (C), and an aqueous medium, wherein the dispersant (A) contains a surfactant, the dispersoid (B) contains a polymer having an ethylenically unsaturated monomer unit, the graft polymer (C) is obtained by graft polymerization of the ethylenically unsaturated monomer with the dispersant (A), a mass ratio [A/(A + B + C)] is 0.001 or more and less than 0.18, a mass ratio [C/(A + B + C)] is 0 or more and less than 0.04, and the total content of the dispersant (A), the dispersoid (B), and the graft polymer (C) is 35 to 70 mass%. A vinyl polymer to be obtained by suspension polymerization of a vinyl compound using the dispersion stabilizer has good plasticizer absorption. Further, the number of fish-eyes that occur when the vinyl polymer is formed is small, and the hue deterioration is also suppressed. Further, the dispersion stabilizer also has excellent handleability.
本发明提供了一种用于悬浮聚合的分散稳定剂,该分散稳定剂由含有分散剂(A)、分散体(B)、接枝聚合物(C)和
水介质的
水乳液组成,其中分散剂(A)含有表面活性剂、接枝聚合物 (C) 是通过
乙烯不饱和单体与分散剂 (A) 的接枝聚合得到的,质量比 [A/(A + B + C)] 为 0.001 或以上且小于 0.18,质量比 [C/(A + B + C)]为 0 或以上且小于 0.04,分散剂 (A)、分散体 (B) 和接枝聚合物 (C) 的总含量为 35 至 70 质量%。使用分散稳定剂对
乙烯基化合物进行悬浮聚合得到的
乙烯基聚合物具有良好的
增塑剂吸收性。此外,
乙烯基聚合物形成时出现的鱼眼数量较少,色调劣化也得到了抑制。此外,该分散稳定剂还具有极佳的操作性。