Polymer-modified rubber composition

Abstract

A polymer-modified rubber composition is formed by blending together about 5% to about 60% vulcanized styrene-butadiene rubber crumb; about 5% to about 60% uncured rubber; about 5% to about 30% styrene-based thermoplastic resin; about 1% to about 10% homogenizing agent adapted to facilitate blending of aromatic-based with non aromatic-based polymers; and about 1% to about 10% curing agent for the uncured rubber; to form a blend wherein the thermoplastic resin (c) is substantially homogeneously blended with the rubbers (a) and (b). All major components of the composition may be derived from the post industrial and post consumer waste stream. The compositions have excellent physical properties, especially stiffness and stiffness retention at elevated temperatures.

Dependencies are inferred from the claim text.