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:
Jun. 27, 1995
Filed:
Nov. 09, 1993
Thomas F Knauf, Sarnia, CA;
Akhtar Osman, Sarnia, CA;
Polysar Rubber Corporation, Sarnia, CA;
Abstract
A process for producing high cis-1,4-polybutadienes using a catalyst system based on a rare earth compound that exhibits improved catalytic activity is provided which process comprises polymerizing 1,3-butadiene in a polymerization medium comprising a hydrocarbon solvent at a temperature of from about 0.degree. C. to about 120.degree. C. in the presence of a catalyst system which is a mixture of (1) a rare earth carboxylate selected from the group of neodymium carboxylates wherein the carboxylate has from 4 to 12 carbon atoms, (2) an alkyl aluminum chloride selected from the group of compounds represented by the formulae R.sup.2 AlCl.sub.2, R.sup.2.sub.3 Al.sub.2 Cl.sub.3 and R.sup.2.sub.2 AlCl wherein R.sup.2 is a hydrocarbon residue having from 8 to 12 carbon atoms and (3) an organo aluminum compound of the formula R.sup.3.sub.2 AlH wherein R.sup.3 is an alkyl group having from 2 to 6 carbon atoms, the ratio of the mols of the rare earth carboxylate to the mols of (2) plus (3) is in the range from about 1:1.5 to about 1:100, to the desired conversion.