US Patent Issued to Bridgestone on Nov. 25 for "Polymerization processes for the production of cis-1,4-polydienes" (Ohio Inventors)

ALEXANDRIA, Va., Nov. 25 -- United States Patent no. 12,479,935, issued on Nov. 25, was assigned to Bridgestone Corp. (Chuo-ku, Japan).

"Polymerization processes for the production of cis-1,4-polydienes" was invented by Steven M. Baldwin (Akron, Ohio) and Walter A. Salamant (Akron, Ohio).

According to the abstract* released by the U.S. Patent & Trademark Office: "A process for preparing a polydiene, the process comprising (i) preparing an active catalyst composition by combining a rare-earth compound including a rare-earth metal, an alkylating agent, an aluminoxane, and optionally a halogen-containing compound, where the catalyst composition includes halogen at molar ratio to the rare-earth metal of from about 0.5:1 to about 2.0:1; and (i...