Process for the preparation of block copolymers for tire tread compositions, and these copolymers
US7504454B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 7, 2005 |
| Grant date | Mar 17, 2009 |
| Priority date | — |
| Expiry date | Oct 10, 2026 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L53/02
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A process for the preparation of a functionalized, coupled or starred block copolymer which is usable in a sulphur-cross-linkable rubber composition of reduced hysteresis in the cross-linked state, one at least of said blocks consisting of a polyisoprene and at least one other block consisting of a diene elastomer other than a polyisoprene the molar ratio of units originating from one or more conjugated dienes of which is greater than 15%. The process includes the steps of: copolymerization of one or more monomers comprising a conjugated diene other than isoprene using a catalytic system comprising at least one hydrocarbon solvent, a compound A of a metal of group IIIA, a compound B of an alkaline-earth metal and a polymer initiator C comprising a C—Li bond which is formed of a monolithiated polyisoprene intended to form the polyisoprene block, and addition to the product of the copolymerization of a functionalizing, coupling or starring agent comprising an acetoxy group and of formula Rn—Sn—(O—CO—R′)4−n, where n is a natural integer of from 0 to 4 and where R and R′ are each alkyl, cycloalkyl, aryl or aralkyl groups which may be identical or different, so that said or each block f…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.