Abstract: A modifier for thermoplastic resin, comprising polytetrafluoroethylene (A), and an alkyl (meth)acrylate-based polymer (B) containing 70% by weight or more of a constituent unit composed of an alkyl (meth)acrylate carrying an alkyl group having 1 to 4 carbon atoms; and a thermoplastic resin composition containing this modifier.

Abstract: The present invention provides a processing aid that reduces ungelled products and flow marks generated on a sheet, and improves releasability of the sheet from the metallic surface of a roll, with the processing aid comprising: a copolymer (A) obtained by copolymerizing a monomer mixture comprising 70 to 90% by weight of methyl methacrylate, 10 to 30% by weight of acrylate or methacrylate other than methyl methacryrate and a different type of monomer capable of being copolymerized with those monomers; and a copolymer (B) obtained by copolymerizing a monomer mixture comprising at least 30% by weight of methyl methacrylate and a monomer having as constitutional units at least one type selected from methacrylates other than methyl methacrylate, acrylates, aromatic alkenyl compounds and other monomers.