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. 30, 1999
Filed:
Dec. 26, 1997
Young-Hoon Ko, Taejeon, KR;
Hoo-Chae Kim, Taejeon, KR;
Korea Kumho Petrochemical Co., Ltd., Seoul, KR;
Abstract
There is provided a method for selectively hydrogenating a living polymer having olefinic double bonds. A monomer having at least one conjugated double bond, optionally together with an olefinic monomer, is polymerized in the presence of an alkyllithium polymerization initiator, to give a living polymer. This olefinic living polymer is reacted with a hydrocarbon compound, to give a deactivated living polymer and a hydrocarbon lithium compound. The double bonds within the conjugated dien units of the polymer are selectively hydrogenated in the presence of a monocyclopentadienyltitanium compound which is under the influence of the hydrocarbon lithium compound. The hydrocarbon, which acts as a deactivator of the living polymer, terminates the anion polymerization occurring due to an activated anion of the living polymer and thus, prevents the intermolecular cross-linking of the polymers so that the gelation of the polymers does not occur. In addition, the hydrocarbon lithium serves as a reducing agent for the hydrogenating catalyst, monocyclopentadienyltitanium compound, so that a high selectivity and hydrogenation efficiency can be obtained without accurate adjustment of Li/Ti mole ratio.