Polymer scale preventive agent
AssigneeShin-Etsu Chemical Co., Ltd.
InventorsToshihide Shimizu, Mikio Watanabe
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Abstract
A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising a condensation product of (A) hydrazine and (B) a quinone compound. Where the monomer is polymerized in a polymerization vessel having, on its inner wall surface, a coating comprising the condensation product, deposition of polymer scale can be effectively prevented not only on the liquid phase part in the polymerization vessel but also near the interface between the gas phase part and the liquid phase part, so that the thus obtained polymer can provide a molded item having few fish eyes and low in initial coloration, when the polymer is molded into a sheet or the like.
Claims12
A polymer scale preventive agent for use in polymerization of a monomer having an ethylenically unsaturated double bond, comprising a condensation product of (A) hydrazine, and (B) a quinone compound, said condensation product having been prepared by reacting the hydrazine (A) and the quinone compound (B) in an amount of 0.01 to 10 parts by weight per part by weight of said hydrazine (A) in a solvent under a total concentration of (A) and (B) of 0.5 to 20% by weight at a temperature of 25.degree.-100.degree. C. for 5 to 100 hours.
A polymerization vessel for polymerizing a monomer having an ethylenically unsaturated double bond, which polymerization vessel has, on its inner wall surface, a coating comprising a condensation product of
- (A) hydrazine, and
- (B) a quinone compound.
Dependencies are inferred from the claim text.