Dispersion stabilizer for suspension polymerization of vinyl compound

Abstract

A dispersion stabilizer for suspension polymerization of a vinyl compound containing a vinyl alcohol polymer (A) having a content of an ethylene unit of 0.5 to 10 mol %, a degree of saponification of 60 mol % or more and a degree of polymerization of 600 or more and a vinyl alcohol polymer (B) selected from the group consisting of a vinyl alcohol polymer (B1) having a content of an ethylene unit of 0.5 to 10 mol %, a degree of saponification of 20 to 80 mol % and a degree of polymerization of 100 to 600, a vinyl alcohol polymer (B2) having a degree of saponification of 20 to 60 mol % and a degree of polymerization of 100 to 600 and a vinyl alcohol polymer (B3) having a content of an ethylene unit of 0.5 to 10 mol %, a degree of saponification of 90 mol % or more and a degree of polymerization of 1,000 or more.

Dependencies are inferred from the claim text.