Patent US3681306A successfully refreshed from Google Patents.
US3681306A
Expired / Lapsed
US
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Epdm polymerization process
Assignee: EIDP Inc
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Filing: 1969-10-24
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Granted: 1972-08-01
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Expires: 1989-10-24
Abstract
Abstract PROCESS FOR PRODUCING AN ETHYLENE/ALPHAOLEFIN COPOLYMER HAVING GOOD PROCESSABILITY BY POLYMERIZING THE MONOMERS IN AT LEAST TWO CONSECUTIVE STAGES UNDER STABLE POLYMERIZATION CONDITIONS AT A TEMPERATURE LESS THAN ABOUT 150*C. AT AN AVERAGE ETHYLENE/ALPH-OLEFIN MOLAR RATIO IN ONE STAGE AT LEAST 1.3 TIMES THE RATIO IN THE OTHER STAGE, TO PRODUCE A COPLYMER CONTAINING 20-80% BY WEIGHT EHTYLENE UNITS AND HAVING A MOLECULAR WEIGHT DISTRIBUTION AT LEAST 20% BROADER THAN THAT OF A SIMILAR POLYMER PREPARED IN A SINGLE STAGE.
Inventors
- 👤 John Francis Wehner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:18
CPC Classifications
C; C08; C08F; C08F210/00
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) | 1975-08-01 | 1976-01-31 | 1976-08-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-01 | 1980-01-31 | 1980-08-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-01 | 1984-01-31 | 1984-08-01 | $7700.00 | Window Closed / Lapsed |