METHOD FOR PRODUCING VINYL CHLORIDE-BASED POLYMER

摘要

PROBLEM TO BE SOLVED: To provide a method for producing a vinyl chloride-based polymer having a high bulk specific gravity and good quality in good productivity by using a heat-removing method using a reflux condenser by improving the reduction of the bulk specific gravity caused by the reflux condenser. SOLUTION: The method for producing the vinyl chloride-based polymer comprises removing the heat of≥30% of the total calorific value by the polymerization by the reflux condenser and continuously adding 1-15 pts. wt. vinyl chloride monomer based on 100 pts. wt. vinyl chloride-based monomer fed before starting the polymerization in the following specified period when the vinyl chloride-based monomer is subjected to a suspension polymerization in an aqueous medium under a condition of≤6 hr polymerization time by using a polymerization initiator and a dispersant: the period for additionally feeding the vinyl chloride monomer is within a period while the polymerization conversion is 40-65 wt.%, within a period while the polymerization conversion of the polymerization progressing in the additionally feeding period is 5-20 wt.%, and within a period while a polymerization rate is over 1.3 times of an average polymerization rate. COPYRIGHT: (C)2004,JPO