Patent ID: 9670349
Date: 2017-06-06
CPC Classifications: C08F,C08G,C08J,C08L

Claim:
1. A polyvinylchloride (PVC) foam processing aid comprising: 50 to 90% by weight of a styrene-acrylonitrile copolymer; and 50 to 10% by weight of an alkyl methacrylate-alkyl acrylate copolymer, wherein the styrene-acrylonitrile copolymer has a weight average molecular weight (Mw) of 2,000,000 to 5,000,000 g/mol, and the alkyl methacrylate-alkyl acrylate copolymer has a weight average molecular weight (Mw) of 200,000 to 1,000,000 g/mol, wherein the alkyl methacrylate-alkyl acrylate copolymer surrounds the styrene-acrylonitrile copolymer, and wherein the amount of an acrylonitrile monomer and a styrene monomer in the styrene-acrylonitrile copolymer is 13 to 28% by weight and 38 to 66% by weight, respectively, based on 100% by weight of the total monomer content of the PVC foam processing aid, and wherein the amount of an alkyl acrylate monomer and an alkyl methacrylate monomer in the alkyl methacrylate-alkyl acrylate copolymer is 2.5 to 10% by weight and 7.5 to 40% by weight, respectively, based on 100% by weight of the total monomer content of the PVC foam processing aid.