Selective hydrogenation method of living polymer having olefinic double bond
US5994477A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 26, 1997 |
| Grant date | Nov 30, 1999 |
| Priority date | — |
| Expiry date | Dec 26, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08F8/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
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 r…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.