METHOD FOR PRODUCTION OF VINYL CHLORIDE-BASED POLYMER BY SUSPENSION POLYMERIZATION

摘要

A method for preparing a vinyl chloride-based polymer is provided to obtain a vinyl chloride-based polymer having a high bulk specific gravity and excellent processability with a high productivity. A method for preparing a vinyl chloride-based polymer comprises a step of carrying out suspension polymerization of vinyl chloride monomers in the presence of a protection colloid agent and a polymerization initiator, wherein the vinyl chloride monomers are further introduced in at least two portions during a period corresponding to a polymerization conversion of 30-70%. Particularly, the vinyl chloride monomers are further introduced during a period corresponding to a polymerization conversion of 30-40%, and then during a period corresponding to a polymerization conversion of 60-70%.