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:
Jul. 16, 2002
Filed:
Oct. 01, 2001
Wen-Liang Hsu, Cuyahoga Falls, OH (US);
Adel Farhan Halasa, Bath, OH (US);
Barry Allen Matrana, Akron, OH (US);
The Goodyear Tire & Rubber Company, Akron, OH (US);
Abstract
Tire rubbers which are prepared by anionic polymerization are frequently coupled with a suitable coupling agent, such as a tin halide, to improve desired properties. It has been unexpectedly found that greatly improved properties for tire rubbers, such as lower hysteresis, can be attained by asymmetrically coupling the rubber. This invention more specifically discloses an asymmetrical tin-coupled rubbery polymer which is particularly valuable for use in manufacturing tire tread compounds, said asymmetrical tin-coupled rubbery polymer being comprised of a tin atom having at least three polydiene arms covalently bonded thereto, wherein said polydiene arms have a weight average molecular weight which is within the range of about 80,000 to about 300,000, wherein the polydiene arms do not contain blocks of more than about 4 repeat units of vinyl aromatic monomers, and wherein the ratio of the weight average molecular weight to the number average molecular weight of the asymmetrical tin-coupled rubbery polymer is within the range of about 1.4 to about 2.0.