PRODUCTION OF VINYL CHLORIDE POLYMER

摘要

PROBLEM TO BE SOLVED: To stably produce a vinyl chloride polymer which has a high bulk density and is suitable for high-speed extrusion molding in no need of special operation on polymerization. SOLUTION: In the suspension polymerization of vinyl chloride monomer or that selected from a mixture thereof containing monomers copolymerizable with the same in the presence of an oil-soluble polymerization initiator in an aqueous medium, at least one kind of polyvinyl alcohol with a saponification degree of >=85mol% is used as a dispersant in an amount of 20-60wt.% based on the whole amount of the dispersants. In addition, an acidic component is added to the polymerization system in an amount of 2.0×10<-5> to 1.0×10<-2> mole.