Process for forming thermoplastic material from granular scrap material

摘要

A process forming a moldable material from a granular scrap material such as a high grade reground rubber and a thermoplastic polymer such as a butadiene-styrene block copolymer sold under the trademark Kraton-D-3202 by Shell Chemical Company. A substantially uniformly distributed mixture of the reground rubber and the cohesive base material in a ratio of at least about 1:1 is processed under sufficient pressure and temperature to form a semi-stable moldable product. The semi-stable moldable product is then subjected or maintained under sufficient pressure to form a stable moldable product. The ratio of reground rubber to cohesive base material may be 7:3 or higher, while pressure on the semi-stable product may generally be in the range of 1800 psi or higher. The moldable product may be subsequently molded, preferably with high fill velocities and maximum venting.