CHEMICALLY FUNCTIONALIZED RENEWED RUBBER COMPOSITION

Today, rubber reclaim material exhibits excellent processability but compromises compound properties, whereas alternative options of recycled material are either cost prohibitive, degrade compound performance, or lead to unacceptable processing behavior. The renewed rubber of this invention can be processed much more easily than conventional recycled rubber compositions. It also consistently exhibits an array of better overall cured rubber properties with only minimal variations in characteristics, by using feedstocks made by various grinding methods. In the chemical functionalization of the renewed rubber compositions of this invention, the sulfur-sulfur bonds in micronized rubber powder are broken to partially devulcanize the rubber, with only a minimal number of carbon-carbon double bonds in the backbone of the polymer being broken. This allows for the renewed rubber of this invention to be used in rubber formulations that are used in manufacturing a wide array of rubber products, including tires, power transmission belts, conveyor belts, hoses, and a wide array of other products. The present invention more specifically discloses a method for manufacturing an environmentally friendly, chemically functionalized, renewed rubber composition having a highly desirable combination of physical properties and which exhibits excellent processability comprising the steps of (1) blending a micronized rubber powder with a processing aid and a chemical functionalizing agent to produce a blended mixture; (2) processing the blended mixture under conditions of high shear and low temperature to produce a reacted mixture; (3) adding a stabilizer to the reacted mixture to produce the chemically functionalized renewed rubber composition.