Vinyl chloride-propylene copolymers having increased porosity

摘要

Vinyl chloride-propylene copolymer resin having improved porosity as shown by an increased irreversible plasticizer take-up is produced by the suspension polymerization of vinyl chloride and propylene in the presence of a binary suspension system of a hydroxypropylmethyl cellulose having 19-30% methoxyl and 4-12% hydroxypropoxyl substitution and a 30-50 mole % hydrolyzed polyvinyl alcohol.