Foamable PVC resin formulation, process for foaming, and product thereof

摘要

A foamable polyvinyl chloride (PVC) resin formulation containing (1) a copolymer formed by emulsion polymerizing from about 70% to about 90% vinyl chloride, from about 5% to about 15% vinyl acetate and from about 5% to about 15% of a bis(hydrocarbyl)vinylphosphonate; (2) a polyester or epoxy plasticizer (or mixture thereof) and (3) 4,4'-oxybis (benzene sulfonyl hydrazide) is foamed to form a product having a smooth unblistered surface, good cell quality and medium density. The foaming can take place at a temperature of from about 320 DEG F. (160 DEG C.) to about 400 DEG F. (204 DEG C.) for a period of time of from about 6 to about 20 minutes.