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. 06, 1999
Filed:
Oct. 07, 1998
Kenneth Floyd Castner, Uniontown, OH (US);
The Goodyear Tire & Rubber Company, Akron, OH (US);
Abstract
The synthesis of cis-1,4-polyisoprene by polymerizing isoprene with a catalyst system which is comprised of a titanium tetrahalide, a trialkylaluminum compound and diphenylether is plagued with the formation of gel. This invention is based upon the unexpected discovery that gel formation can be reduced by conducting such polymerizations in the presence of a diarylamine, such as para-styrenated diphenylamine. The subject invention more specifically discloses a process for synthesizing cis-1,4-polyisoprene having a low gel content which comprises polymerizing isoprene in an inert organic solvent with a preformed catalyst system which is made by reacting an organoaluminum compound with titanium tetrahalide, such as titanium tetrachloride, in the presence of at least one ether, wherein said polymerization is conducted at a temperature which is within the range of about 0.degree. C. to about 100.degree. C., and wherein said polymerization is conducted in the presence of a diarylamine.