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US3645992A
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US
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Process for preparation of homogenous random partly crystalline copolymers of ethylene with other alpha-olefins
Assignee: DuPont Canada Inc
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Filing: 1968-02-15
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Granted: 1972-02-29
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Expires: 1988-02-15
Abstract
Abstract PREPARATION OF COPLYMERS OF ETHYLENE AND AN ALPHA OLEFIN HAVING A LEAST FOUR CARBON ATOMS USING AN INERT SOLVENT AND A CATALYST FORMED USING PARTICULAR RATIOS OF AN ALUMINUM HALIDE AND A VANADUM COMPOUND.
Inventors
- 👤 Clayton Trevor Elston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:34
CPC Classifications
C; C08; C08F; C08F210/00; C08F210/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |