Method of producing polymer compositions based on chlorinated polyethylene

A method for producing a blended polymer composition comprising blending

• I. an interpolymer prepared by contacting
• A. a polymer component selected from the group consisting of chlorinated polyethylene of a degree of chlorination of 10-50 percent and a mixture consisting of 50-90 percent by weight of said chlorinated polyethylene and 10-50% by weight of a copolymer selected from an ethylene-propylene copolymer rubber, an ethylene-propylene-nonconjugated diene terpolymer rubber and an ethylene-vinyl acetate copolymer rubber, with
• B. a monomer mixture comprising
• b.sub.1. at least one monomer selected from styrene, alpha-methyl styrene, t-butyl styrene and chloro-styrene and
• b.sub.2. at least one monomer selected from acrylonitrile and methacrylonitrile
• under polymerization conditions in the presence of a polymerization initiator to form an interpolymer of components (A) and (B) wherein the polymer component (A) and monomer component (B) are suspended in the form of fine particles in a state of separation from each other in an aqueous medium, said component (A) having a particle size of 5-150 Tyler mesh, the weight ratio of said component (A) to component (B) ranging from about 10:90 to about 90:10 with
• Ii. a polymer separately prepared from said component (B), the overall weight ratio of component (A) to component (B) in said blended copolymer being from 5:95 to 50:50.