The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 11, 1993
Filed:
Dec. 20, 1991
David F Lawson, Uniontown, OH (US);
Mark L Stayer, Jr, Mogadore, OH (US);
Thomas A Antkowiak, Rittman, OH (US);
Bridgestone Corporation, Tokyo, JP;
Abstract
Diene polymers or copolymers having improved raw polymer viscosity and reduced hysteresis in the cured and carbon black reinforced state are provided. These diene polymers or copolymers comprise a mixture of diene polymer or copolymer chains containing carbon-tin bonds in the main polymer or copolymer chains and diene polymer or copolymer chains containing terminals derived from fused-ring polynuclear aromatic compounds. The diene polymer or copolymers are prepared by first coupling a portion of the living diene polymer or copolymer chains obtained by anionic polymerization using a tin polyhalide coupling agent and then terminating the remaining living diene polymer or copolymer chains using fused-ring polynuclear aromatic compounds. The resultant diene polymers or copolymers have improved raw polymer viscosity and when compounded with carbon black and cured have reduced hysteresis properties. The polymers can be utilized to form elastomer compositions for tire treads having reduced rolling resistance.