Weatherable resinous composition having improved opacity and impact strength

摘要

A thermoplastic molding composition comprising a grafted rubber and a copolymeric matrix is disclosed. The composition is characterized in that its grafted rubber includes a substrate, a first grafted phase and a subsequent grafted phase which are sequentially grafted to said substrate. The substrate which contains a crosslinked elastomer is grafted with a first grafted phase and with a subsequent grafted phase, both phases containing copolymers of at least one vinylaromatic monomer and at least one member selected from the group consisting of (meth)acrylonitrile and alkyl (meth)acrylate. The relative ratios of the monomers making up the copolymerized phases differ one from the other. The grafted rubber is present in particulate form having a weight average particle size of about 0.1 to 1.0 microns. The composition features improved impact strength and reduced opacity.