Patent US3682865A successfully refreshed from Google Patents.
US3682865A
Expired / Lapsed
US
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Polymerisation process
Assignee: Evonik LIL Ltd
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Filing: 1969-05-19
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Granted: 1972-08-08
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Expires: 1989-05-19
Abstract
Abstract NOVEL POLYESTERS CHARACTERIZED BY THE PRESENCE OF, AS THE MAIN CHAIN-EXTENDING GROUPS, GROUPS OF THE TYPE -(-CO-A-CO-O-E-O-)X -(-CO-X-O-)Y WHERE X AND Y ARE SMALL INTEGERS (E.G. 1 TO 4). THE NOVEL POLYESTERS ARE PRODUCED BY THE REACTION TOGETHER IN A CONTROLLED MANNER OF A LACTONE AND A POLYCARBOXYLIC ANHYDRIDE AND AN EPOXIDE (OXIRANE OR OXETANE) OF FORMULAE X<(-O-CO-), O<(-CO-A-CO-), AND E<(-O-) RESPECTIVELY AN ACTIVE HYDROGEN ATOM COMPOUND IS GENERALLY USED AS INITIATOR. ETHERIFICATION INHIBITORS AND/OR LACTONE POLYMERISATION CATALYST MAY BE EMPLOYED. THE REACTION IS CONTROLLED SO THAT THE RATE OF CONSUMPTION OF EACH OF THE REACTANTS IS SUBSTANTIALLY IDENTICAL.
Inventors
- 👤 Victor F Jenkins
- 👤 Geoffrey P Newton
- 👤 Michael J Beeken
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:41
CPC Classifications
C; C08; C08G; C08G63/00; C08G63/02; C08G63/60; C08G63/78; C08G63/82; C08G63/823
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) | 1975-08-08 | 1976-02-07 | 1976-08-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-08 | 1980-02-07 | 1980-08-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-08 | 1984-02-07 | 1984-08-08 | $7700.00 | Window Closed / Lapsed |