Ruth D Gallagher

US Patent:

39446310, Mar 16, 1976

Filed:

Feb 1, 1974

Appl. No.:

5/438918

Inventors:

Arthur J. Yu - Stamford CT
Ruth E. Gallagher - Dobbs Ferry NY

Assignee:

Stauffer Chemical Company - Westport CT

International Classification:

C08L 2512
C08L 2906
C08L 3102
C08L 3320

US Classification:

260881

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. degree. 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.