Patent ID: 6984686
Filing Date: 2006-01-10
Classification: C08F,C08L

Abstract:
1. A rubbery polymer having improved properties, which is comprised of repeat units which are comprised of (a) butyl acrylate, or optionally a mixture of butyl acrylate and 2-ethylhexyl acrylate containing up to about 40 percent 2-ethylhexyl acrylate, (b) at least one member selected from the group consisting of methyl methacrylate, ethyl methacrylate, methyl acrylate, and ethyl acrylate, (c) optionally, about 0% to about 40% of an alkoxy ethyl acrylate or an alkoxy ethyl methacrylate, (d) acrylonitrile, (e) styrene, and (f) a crosslinking agent; wherein about 1% to about 10% of a monomer containing reactive cure sites selected from the group consisting of hydroxyl groups, glycidyl groups, carboxylic acid groups, and unsaturated cure sites is incorporated into the rubbery polymer, wherein the rubbery polymer is synthesized by a two-step aqueous emulsion polymerization process, wherein (a) the butyl acrylate, (b) the member selected from the group consisting of methyl methacrylate, ethyl methacrylate, methyl acrylate, and ethyl acrylate, (c) optionally, the alkoxy ethyl acrylate or the alkoxy ethyl methacrylate, (d) a portion of the acrylonitrile (f) the cross-linking agent, and (g) the monomer containing reactive cure sites are polymerized in the first polymerization step, wherein (d) additional acrylonitrile, (e) the styrene, and (f) additional cross-linking agent are polymerized in the second polymerization step, and wherein the second polymerization step is void of methyl methacrylate.