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US4526934A
Expired / Lapsed
US
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Branched styrene-butadiene copolymers and pneumatic tires using the same
Assignee: Bridgestone Corp
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Filing: 1983-03-08
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Granted: 1985-07-02
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Expires: 2003-03-08
Abstract
Abstract A branched styrene-butadiene copolymer and a pneumatic tire using the same as a tread base rubber are disclosed. This copolymer is produced by coupling an active styrene-butadiene copolymer anion, which is obtained by polymerizing styrene and butadiene in a hydrocarbon solvent in the presence of ether or a tertiary amine and an initiator of an organolithium compound, with a tin halide compound. In the copolymer, the ratio of branched copolymer connected with tin-butadienyl bond is at least 20% by weight, and the content of bound styrene is not less than 3% by weight but less than 25% by weight, and the content of vinyl bond in butadiene portion is not less than 30% but less than 50%.
Inventors
- 👤 Noboru Oshima
- 👤 Isamu Shimizu
- 👤 Yoshito Yoshimura
- 👤 Tatsuo Fujimaki
- 👤 Seisuke Tomita
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:25
CPC Classifications
C; C08; C08C; C08C19/00; C08C19/30; C08C19/42; C08C19/44; B; B60; B60C; B60C1/00; B60C1/0016
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
149 words
A branched styrene-butadiene copolymer obtained by coupling an active styrene-butadiene copolymer anion, prepared by the process comprising (a) polymerizing styrene and butadiene in the presence of ether or a tertiary amine and an initiator of an organolithium compound in a hydrocarbon solvent, (b) adding 1 to 20 mole of 1,3 butadiene per 1 gram atom of lithium in the initiator to the resulting polymer of step (a), and (c) coupling the resulting styrene butadiene copolymer of step (b) with a tin halide compound, wherein : (I) a content of branched copolymer connected with tin-butadienyl bond in said copolymer is at least 20% by weight; (II) a content of bound styrene in said copolymer is not less than 3% by weight but less than 25% by weight; and (III) a content of vinyl bond in the butadiene portion of said copolymer is not less than 30% but less than 50%.
Claim 2
Dependent Claim
149 words
A branched styrene-butadiene copolymer obtained by coupling an active styrene-butadiene copolymer anion, prepared by the process comprising (a) polymerizing styrene and butadiene in the presence of ether or a tertiary amine and an initiator of an organolithium compound in a hydrocarbon solvent, (b) adding 1 to 20 mole of 1,3 butadiene per 1 gram atom of lithium in the initiator to the resulting polymer of step (a), and (c) coupling the resulting styrene butadiene copolymer of step (b) with a tin halide compound, wherein : (I) a content of branched copolymer connected with tin-butadienyl bond in said copolymer is at least 20% by weight; (II) a content of bound styrene in said copolymer is not less than 3% by weight but less than 25% by weight; and (III) a content of vinyl bond in the butadiene portion of said copolymer is not less than 30% but less than 50%.
Claim 3
Dependent Claim
20 words
A branched styrene-butadiene copolymer according to claim 1, wherein said content of bound styrene is 3 to 15% by weight.
Claim 4
Dependent Claim
20 words
A branched stryene-butadiene copolymer according to claim 1, wherein said content of bound styrene is 5 to 15% by weight.
Claim 5
Dependent Claim
42 words
A branched styrene-butadiene copolymer according to claim 1, wherein the initial polymerization temperature is 0°-50° C., the maximum access temperature is not more than 120° C. and the rising of polymerization temperature from the polymerization initiation temperature is at least 30° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-07-01 | 1988-12-31 | 1989-07-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-07-01 | 1992-12-31 | 1993-07-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-07-01 | 1996-12-31 | 1997-07-02 | $7700.00 | Window Closed / Lapsed |