Preparation process for block copolymers for tire tread compositions, and such copolymers
US7205360B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 2004 |
| Grant date | Apr 17, 2007 |
| Priority date | — |
| Expiry date | Apr 13, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S152/905
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A preparation process for a copolymer having two blocks usable in a sulphur-cross-linkable rubber composition of reduced hysteresis in the cross-linked state, such a block copolymer in which one of the blocks is a polyisoprene and the other a diene elastomer other than a polyisoprene, and this rubber composition for tire treads. A process for the preparation of this copolymer involves copolymerizing one or more monomers including a conjugated diene other than isoprene using a catalytic system including at least one hydrocarbon solvent, a compound A of a metal of group IIIA, a compound B of an alkaline-earth metal and a polymeric initiator C having a C—Li bond which is constituted of a monolithiated polyisoprene intended to form the polyisoprene block, the number-average molecular weight Mn1 of the polyisoprene block being between 2,500 and 20,000 g/mol. A copolymer is obtained in which the block composed of the diene elastomer has a number-average molecular weight Mn2 of between 65,000 and 350,000 g/mol and a content of trans-1,4 linkages equal to or greater than 70%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.