Patent ID: 7973101

Claim:
A resin composition comprising (A) a biodegradable (3-hydroxyalkanoate) copolymer, (B) a graft copolymer, and (C) an acrylic processing modifier, wherein the biodegradable (3-hydroxyalkanoate) copolymer (A) has a recurring unit represented by the formula (1): [—CHR—CH 2 —CO—O—] (wherein R represents an alkyl group represented by C n H 2n+1 ; and n is an integer of 1 to 15) and wherein the biodegradable (3-hydroxyalkanoate) copolymer (A) is poly[(3-hydroxybutyrate)-co-(3-hydroxyhexanoate)] having a (3-hydroxybutyrate) recurring unit and a (3-hydroxyhexanoate) recurring unit and the constituent ratio of the recurring units in the poly[(3-hydroxybutyrate)-co-(3-hydroxyhexanoate)] is represented by (3-hydroxybutyrate) unit/(3-hydroxyhexanoate) unit=99/1 to 80/20 (mol/mol); the graft copolymer (B) is obtained by graft polymerization of a vinyl monomer onto at least one rubber selected from the group consisting of (b1) a composite rubber comprising a polyorganosiloxane component and a polyalkyl (meth)acrylate component, (b2) an acrylic rubber, and (b3) a diene rubber constituted with a diene monomer and the vinyl monomer in the graft copolymer (B) comprises 70 to 100% by weight of at least one vinyl monomer selected from the group consisting of a vinyl cyanide monomer, an aromatic vinyl monomer, an acrylic ester and methacrylic ester, and 30 to 0% by weight of other vinyl monomer that is copolymerizable therewith; the acrylic processing modifier (C) has a weight average molecular weight (Mw) of 500,000 to 10,000,000; the resin composition comprises 0.5 to 30 parts by weight of the graft copolymer (B), and 0.1 to 20 parts by weight of the acrylic processing modifier (C) based on 100 parts by weight of the biodegradable (3-hydroxyalkanoate) copolymer (A); the biodegradable (3-hydroxyalkanoate) copolymer (A) has a molecular weight of 300,000 to 3,000,000 in terms of the weight average molecular weight; the acrylic processing modifier (C) predominately comprises a copolymer of butyl acrylate and methyl methacrylate, or a copolymer of butyl methacrylate and methyl methacrylate; and wherein the composition contains an antioxidant and a fatty acid amide having 10 to 50 carbon atoms as a nucleating agent.