The present invention provides vinyl halide polymer thermoplastic polymer compositions comprising a multi-stage, or, preferably, two-stage acrylic copolymer polymeric additive having (A) a high Tg, high molecular weight first stage polymer that is free of, in copolymerized form, vinyl aromatic monomers, and having (B) a low Tg, low molecular weight second stage polymer of copolymerized vinyl aromatic containing monomers, wherein the multi-stage acrylic copolymer can be isolated by coagulation and drying and provides compositions having both melt strength and lubrication in thermoplastic processing.
