Patent ID: 7557162
Filing Date: 2009-07-07
Classification: C08F

Abstract:
1. A process for preparing a toughened polymer composition, comprising the steps of: combining a rubber component and a matrix polymer, said matrix polymer being a polyolefin; crosslinking the rubber component in the presence of the matrix polymer with a crosslinking agent at a temperature above the melting point of the matrix polymer to form a thermoplastic elastomer component; and blending the thermoplastic elastomer component with a thermoplastic polyolefin polymer component to form the toughened polymer composition, said thermoplastic polyolefin polymer comprising at least 50% by weight of a homopolymer, wherein the rubber component is present in an amount from about 2 to about 60 carts by weight per 100 parts by weight of the matrix polymer and the thermoplastic polyolefin polymer component, wherein the toughened polymer composition contains less than 20 parts by weight of extender oil per 100 parts by weight of the rubber component, wherein the toughened polymer composition optionally includes a compatibilizer, wherein the toughened polymer composition has a greater impact resistance when compared to either a corresponding composition wherein the rubber component is uncured, or the thermoplastic polyolefin polymer component alone, or a combination thereof, and wherein the toughened polymer composition is substantially free of plasticizer, wherein the thermoplastic polyolefin polymer component is derived from at least one olefin monomer having from 2 to about 14 carbon atoms, wherein the matrix polymer of the thermoplastic elastomer component is derived from at least one olefin monomer having from 2 to 14 carbon atoms, wherein the rubber component of the thermoplastic elastomer component is derived from at least two different aloha olefin monomers, or is styrene butadiene rubber, hydrogenated styrene butadiene rubber, butyl rubber, butyl-paramethyl styrene copolymer or derivatives thereof styrenic black copolymer, acrylic rubber, nitrile rubber, hydrogenated nitrile rubber, or ethylene methacrylate terpolymer rubber, or any combination thereof; wherein the crosslinked rubber component of the thermoplastic elastomer component has an average particle size of about 0.005 to about 25 microns, and wherein the thermoplastic elastomer component and thermoplastic polyolefin polymer component are melt blended.