PROCESS FOR PREPARING HOMO- AND COPOLYMERS OF VINYL CHLORIDE IN AQUEOUS EMULSION WITH POST ADDITION OF A WATER-SOLUBLE ETHYLENE OXIDE-ETHYLENE GLYCOL ADDUCT

摘要

An aqueous emulsion polymerization process is described for the preparation of vinyl chloride homo- and copolymers which find particular utility as molding resins wherein the emulsifier system comprises, in combination, from 0.05 percent to 3 percent of an alkali metal salt of a sulfated fatty alcohol having from 8-18 C atoms per molecule; and from 0.05 percent to 2 percent of either tallow fatty alcohol or an epoxidized oil of an unsaturated fatty acid, the percentage of each ingredient being based on the weight of the monomer. After the polymerization reaction is substantially completed but prior to spray-drying of the polymerization mixture, there is blended into said mixture from 0.05 percent to 3 percent, by weight of the initial monomer charge, of an ethylene oxide adduct of ethylene glycol having a molecular weight ranging up to about 600. Plastisols of the resin products exhibit excellent dispersion rheologies and air-release properties. Moldings prepared from these resins may, in many instances, be utilized in contact with foodstuffs.