Patent ID: 6069206
Filing Date: 2000-05-30
Classification: C08L

Abstract:
A compatibility agent comprising at least one copolymer selected from the group consisting of:(a) a copolymer of an aromatic vinyl monomer and a different monomer copolymerizable with the aromatic vinyl monomer; and(b) a graft copolymer comprising a rubbery polymer having a glass transition temperature (Tg) of -30.degree. C. or lower and, grafted thereon, a polymer of an aromatic vinyl monomer (1) and a monomer (2) copolymerizable with the aromatic vinyl monomer (1), wherein the polymer is in the form of (i) a mixture of different homopolymers respectively of said monomers (1) and (2), (ii) a copolymer of said monomers (1) and (2), or (iii) a mixture of (i) and (ii);said at least one copolymer of said compatibility agent having a non-uniform distribution with respect to the proportions of component monomers constituting said at least one copolymer, so that said at least one copolymer comprises copolymer molecules having different solubility parameter (SP) values, wherein the difference in SP value between the copolymer molecule having a maximum SP value and the copolymer molecule having a minimum SP value is from 0.4 to 0.6 (cal/cm.sup.3).sup.1/2, and wherein said at least one copolymer has an average SP value of from 10.6 to 11.0 (cal/cm.sup.3).sup.1/2.