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:
Aug. 13, 2002
Filed:
Jun. 09, 2000
Applicant:
Inventor:
Thomas J. Lynch, Akron, OH (US);
Assignee:
Bridgestone Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
L08F 8/42 ;
U.S. Cl.
CPC ...
L08F 8/42 ;
Abstract
A butadiene-type polymer suitable for use as a processing aid in a rubber composition is formed by polymerizing butadiene or other conjugated diene monomers in a solvent, such as hexane, to form a polymer of relatively low molecular weight (around 30-40,000 g/mole). The polymer is coupled with a coupling agent, such as tin tetrachloride, to increase its molecular weight to a level at which conventional desolventizing processes may be used to remove the solvent from the mix. After desolventizing, the polymer is decoupled, by heating, to return the polymer to its original molecular weight.