Patent ID: 8129454
Filing Date: 2012-03-06
Classification: B29C,B29K,C08L

Abstract:
1. A method of reducing die lip build-up during profile extrusion of a thermoplastic article, comprising: profile extruding through a die a thermoplastic composition having a temperature of 220 to 240° C.; and cooling the extruded composition to form an extruded thermoplastic article; wherein the thermoplastic composition comprises wherein the thermoplastic composition comprises less than 1 weight percent of unhydrogenated poly(conjugated diene) rubber; wherein all weight percents are based on the total weight of the thermoplastic composition; wherein the thermoplastic composition exhibits wherein the profile extruding the thermoplastic composition produces an average die lip build-up per hour measured over the course of 8 continuous hours of profile extrusion of the thermoplastic composition, measured at a melt temperature of 233° C. using an annular die having an outside diameter of 24.6 millimeters and an inside diameter of 21.35 millimeters; and wherein the average die lip build-up is less than that produced by a corresponding thermoplastic composition in which the hydrogenated block copolymer is replaced by an equal weight of an unhydrogenated block copolymer.