Polymer composition with improved toughness

摘要

PCT No. PCT/US95/06172 Sec. 371 Date Nov. 7, 1997 Sec. 102(e) Date Nov. 7, 1997 PCT Filed May 16, 1995 PCT Pub. No. WO96/36651 PCT Pub. Date Nov. 21, 1996A polymer composition is disclosed comprising (A) a first grafted acrylate rubber substrate having an average rubber phase particle size of from about 0.05 to about 0.2 micron; (B) a second grafted acrylate rubber substrate having an average rubber phase particle size of from about 0.2 to about 2 microns; and (C) a matrix polymer wherein each of the first and second rubber substrates are grafted with (i) a vinyl aromatic monomer; (ii) an unsaturated nitrile monomer; and (iii) optionally a compatible polymerizable comonomer based on the total weight of the grafted rubber substrate wherein at least one of the acrylate rubber substrates is a copolymer of from 83 to 98 percent by weight of an acrylate monomer and from 17 to 2 weight percent of an unsaturated nitrile monomer based on the total weight of the acrylate nitrile monomer copolymer rubber; and wherein the composition has an Izod impact value of at least 80 Joules/meter when tested at 23 DEG C. according to ASTM D-256 using a test specimen of 6.35 cmx1.27 cmx0.32 cm.