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US 5,166,277 AGranted
Hydrogenation of unsaturation in low molecular weight diene polymers
AssigneeShell Oil Company
InventorsDaniel E. Goodwin, Carl L. Willis
Life of this patent
Estimating the term…
Abstract
Complete hydrogenation of residual unsaturation in low molecular weight polymers containing conjugated dienes is enhanced by removal of strong lithium bases by filtering or decanting the polymer solution prior to hydrogenation.
Claims11
A process for hydrogenating a diene polymer or copolymer, comprising the sequential steps of:
- anionically polymerizing a conjugated diene hydrocarbon with a lithium initiator in a solvent solution to form a living polymer or copolymer;
- terminating polymerization by sequential addition of one or more compounds that form fine particles of a strong lithium base selected from a group consisting of lithium alkoxides and lithium hydroxides;
- removing the fine particles of the strong lithium base from the solvent solution;
- and
- hydrogenating the polymer or copolymer in the solvent solution with a nickel catalyst.
2 more elements
A process for making a hydrogenated diene polymer having two terminal hydroxy groups, comprising the sequential steps of:
- anionically polymerizing a conjugated diene hydrocarbon with a diadduct of sec-butyllithium and m-diisopropenylbenzene in a solvent solution containing an ether to form a living polymer having a number average molecular weight from 1,000 to 20,000 and predominantly the following structure:
- Li--B--Y--B--Li
- wherein each B represents polymerized units of the conjugated diene hydrocarbon and Y is the residue of the diadduct;
- terminating the polymerization step by sequential addition of ethylene oxide and an alcohol which forms a lithium alkoxide;
- removing the lithium alkoxide from the solvent solution;
- and
- hydrogenating the polymer in the solvent solution with a nickel catalyst.
4 more elements
Dependencies are inferred from the claim text.