Low gloss thermoplastic resin composition

A method for making a low gloss thermoplastic resin composition, comprising forming a substantially homogeneous mixture of:

• (a) a rubber modified thermoplastic resin comprising a discontinuous elastomeric phase and a rigid thermoplastic phase, wherein at least a portion of the rigid thermoplastic phase is grafted to the elastomeric phase;
• and
• (b) a gel polymer, in an amount effective to provide low gloss properties to the composition wherein said gel polymer comprises an inert carrier polymer selected from the group consisting of polycarbonate resin and polystyrene resin and
• (c) a low molecular weight polyolefin polymer, in an amount effective to provide improved impact properties to the composition and to enhance the low gloss properties of the composition whereby ASTM D523 gloss at 60.degree. is below 34.

A low gloss thermoplastic resin composition comprising, based on 100 parts by weight of the resin composition, a mixture of:

• (a) from 70 to 99 parts by weight of a rubber modified thermoplastic resin, said resin comprising from 5 to 50 parts by weight of a discontinuous elastomeric phase, said elastomeric phase comprising a polymer having structural units derived from one or more conjugated diene monomers, and from 50 to 95 parts by weight of a rigid thermoplastic phase, said rigid thermoplastic phase comprising a polymer having structural units derived from one or more monomers selected from vinyl aromatic monomers and monoethylenically unsaturated nitrile monomers, wherein at least a portion of the rigid thermoplastic phase is grafted to the elastomeric phase;
• and
• (b) from 0.5 to 10 parts by weight of a gel polymer, said gel polymer being made by mixing a nitrile-containing polymer with a carrier polymer selected from the group consisting of one or more polycarbonate polymers and polystyrene polymers and reactively extruding the nitrile-containing polymer and said carrier polymer in the presence of a polyepoxide crosslinking agent and an acid catalyst selected from organic acids, mineral acids, Lewis acids and mixtures thereof, and
• (c) from 0.5 to 20 parts by weight of a low molecular weight polyolefin polymer, said low molecular weight polyolefin polymer comprising structural units derived from one or more C.sub.3 -C.sub.16 monoolefin monomers and having a number average molecular weight range of from about 100 to about 5,000 grams per mole whereby ASTM D523 gloss at 60.degree. is below 34.