| abstract |
An impact-resistant and weatherable thermoplastic composition comprising from about 10 to about 50 weight percent of a crosslinked acrylate elastomer having a Tg of less than 25 DEG C., from about 5 to about 35 weight percent of a crosslinked styrene-acrylonitrile copolymer and from about 15 to about 85 weight percent of a non-crosslinked or linear styrene-acrylonitrile copolymer. The composition is made by a three-step sequence comprising emulsion polymerizing of an alkyl acrylate containing at least one crosslinking monomer, emulsion polymerizing a monomer mixture of styrene, acrylonitrile and at least one crosslinking monomer in the presence of the crosslinked acrylate elastomer formed in the previous step, or a reverse sequence of the prior two emulsion polymerization procedures, and, finally, emulsion or suspension polymerizing of styrene, acrylonitrile in the presence of the previously formed product. |