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:
Nov. 10, 1998
Filed:
May. 21, 1997
Kenneth Floyd Castner, Uniontown, OH (US);
The Goodyear Tire & Rubber Company, Akron, OH (US);
Abstract
By utilizing the techniques of this invention, trans-1,4-polybutadiene can be synthesized continuously to a high level of conversion utilizing a low level of a highly active cobalt-based catalyst system. The trans-1,4-polybutadiene made with the cobalt-based catalyst system of this invention also typically has a molecular weight which is acceptable for use in tire applications without the need for employing a molecular weight regulator. It is also not typically necessary to utilize a gel inhibitor, such as carbon disulfide, in the polymerizations of this invention. Since a low level of residual cobalt is present in the trans-1,4-polybutadiene which is made utilizing the catalyst system of this invention, it is much more stable than trans-1,4-polybutadiene made with standard cobalt-based catalyst systems. This invention specifically relates to a process for synthesizing trans-1,4-polybutadiene by polymerizing 1,3-butadiene monomer in the presence of a catalyst system which is comprised of cobalt (III) acetylacetonate, an organoaluminum compound and a para-alkyl-substituted phenol, wherein the cobalt (III) acetylacetonate is mixed with the para-substituted phenol prior to the polymerization. Such polymerizations can be conducted on a batch or a continuous basis.