Method for producing vinyl chloride resins
AssigneeKurara Co., Ltd.
InventorsMakoto Shiraishi, Hiroshi Uchida, Yoshinori Koizumi, Akira Saito
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Abstract
A method for suspension polymerizing vinyl chloride monomer, or a mixture thereof with copolymerizable monomers, employs as a suspension stabilizer a partially saponified polyvinyl alcohol having a degree of saponification between about 60 and about 90 mol percent, and a solubility-in-methanol index at 55.degree. C. in a range of up to about 60 percent.
Claims4
A method for producing a polyvinyl chloride resin comprising suspension polymerizing vinyl chloride monomer in the presence of an effective amount of a suspension stabilizer of a partially saponified polyvinyl alcohol having simultaneously:
- (a) a degree of saponification in the range of from 60 to 90 mol percent;
- (b) a solubility-in-methanol index at 55.degree. C. in the range of from 10 to 60 percent;
- and, (c) a solubility in aqueous solution whereby said suspension stabilizer will not flocculate from a stirred 0.1 percent aqueous solution at a temperature in the range of from 30.degree. C. to 65.degree. C.
Dependencies are inferred from the claim text.