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US4294942A
Expired / Lapsed
US
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Rubbery copolymers of 2,3-dimethyl 1,3-butadiene
Assignee: Goodyear Tire and Rubber Co
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Filing: 1980-02-14
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Granted: 1981-10-13
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Expires: 2000-02-14
Abstract
Abstract There is disclosed copolymers of 2,3-dimethyl-1,3-butadiene with butadiene or isoprene in which the 2,3-dimethyl-1,3-butadiene content ranges from about 20 to about 80 mole percent, characterized in that the microstructure of the 2,3-dimethyl-1,3-butadiene segments range from about 55 to about 65 percent trans-1,4. Also disclosed are copolymers of 2,3-dimethyl-1,3-butadiene with butadiene or isoprene in which the 2,3-dimethyl-1,3-butadiene content ranges from about 20 to about 80 mole percent characterized in that the microstructure of the 2,3-dimethyl-1,3-butadiene segments range from about 40 to about 65 percent trans-1,4 and 1,2 content of said segments does not exceed 20 percent, said copolymers being prepared by bulk polymerization techniques.
Inventors
- 👤 James N. Henderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 17:53
CPC Classifications
C; C08; C08F; C08F297/00; C08F297/02; C08F236/00; C08F236/02; C08F236/04; C08F236/045
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
125 words
Stress crystallizable tapered block copolymers of 2,3-dimethyl-1,3-butadiene and butadiene or isoprene in which the 2,3-dimethyl-1,3-butadiene content ranges from about 20 to about 80 mole percent, characterized in that the said tapered block copolymers have one terminal segment of the block made up almost entirely of 2,3-dimethyl-1,3-butadiene units and the other terminal segment made up almost entirely of units of the other diene, either butadiene or isoprene, between these relatively pure terminal blocks is a central segment of gradually changing composition made up of both 2,3-dimethyl-1,3-butadiene units and units of the other diene, 1,3-butadiene or isoprene, said copolymers being further characterized in that the microstructure of the 2,3-dimethyl-1,3-butadiene segments range from about 55 to about 65 percent trans-1,4 and does not exceed about 20 percent 1,2-microstructure.
Claim 2
Dependent Claim
125 words
Stress crystallizable tapered block copolymers of 2,3-dimethyl-1,3-butadiene and butadiene or isoprene in which the 2,3-dimethyl-1,3-butadiene content ranges from about 20 to about 80 mole percent, characterized in that the said tapered block copolymers have one terminal segment of the block made up almost entirely of 2,3-dimethyl-1,3-butadiene units and the other terminal segment made up almost entirely of units of the other diene, either butadiene or isoprene, between these relatively pure terminal blocks is a central segment of gradually changing composition made up of both 2,3-dimethyl-1,3-butadiene units and units of the other diene, 1,3-butadiene or isoprene, said copolymers being further characterized in that the microstructure of the 2,3-dimethyl-1,3-butadiene segments range from about 55 to about 65 percent trans-1,4 and does not exceed about 20 percent 1,2-microstructure.
Claim 3
Dependent Claim
21 words
Tapered block copolymers according to claim 1 in which the 2,3-dimethyl-1,3-butadiene content ranges from about 20 to about 50 mole percent.
Claim 4
Dependent Claim
21 words
Tapered block copolymers according to claim 1 in which the 2,3-dimethyl-1,3-butadiene content ranges from about 60 to about 80 mole percent.
Claim 5
Dependent Claim
14 words
Tapered block copolymers according to claim 1 which are prepared by bulk polymerization techniques.
Claim 6
Dependent Claim
23 words
Tapered block copolymers according to claim 1 in which the 1,2 content of the 2,3-dimethyl-1,3-butadiene segments is at least 5 percent 1,2 microstructure.
References Cited (Backward Citations)
US3607982A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-10-12 | 1985-04-13 | 1985-10-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-10-12 | 1989-04-13 | 1989-10-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-10-12 | 1993-04-13 | 1993-10-13 | $7700.00 | Window Closed / Lapsed |