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US3216977A
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Anionic polymerization of lactams with methylene oxazolidine-4, 5-dione compounds as activators
Assignee: EIDP Inc
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Filing: 1962-12-13
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Granted: 1965-11-09
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Expires: 1982-12-13
Abstract
No abstract record available.
Inventors
- 👤 Harold G Brouns
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:13
CPC Classifications
C; C07; C07D; C07D263/00; C07D263/02; C07D263/30; C07D263/34; C07D263/44; C08; C08G; C08G69/00; C08G69/02; C08G69/08; C08G69/14; C08G69/16; C08G69/18; C08G69/20
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
65 words
IN THE PROCESS FOR THE POLYMERIZATION OF LACTAMS CONTAINING FROM 3 TO 12 CARBON ATOMS IN THE LACTAM RING TO POLYAMIDES IN THE PRESENCE OF A LACTAM-BASE SALT PREPARED BY HEATIANG FROM ABOUT 0.1 TO 10 MOLE PERCENT BASE WITH A LACTAM, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT SAID POLYMERIZATION BY ADDING FROM ABOUT 0.05 TO 5 MOLE PERCENT OF A COCATALYST HAVING THE FORMULA:
Claim 2
Dependent Claim
65 words
IN THE PROCESS FOR THE POLYMERIZATION OF LACTAMS CONTAINING FROM 3 TO 12 CARBON ATOMS IN THE LACTAM RING TO POLYAMIDES IN THE PRESENCE OF A LACTAM-BASE SALT PREPARED BY HEATIANG FROM ABOUT 0.1 TO 10 MOLE PERCENT BASE WITH A LACTAM, THE IMPROVEMENT WHICH COMPRISES CARRYING OUT SAID POLYMERIZATION BY ADDING FROM ABOUT 0.05 TO 5 MOLE PERCENT OF A COCATALYST HAVING THE FORMULA:
References Cited (Backward Citations)
US3017391A
Cited
GB900150A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1968-11-08 | 1969-05-10 | 1969-11-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1972-11-08 | 1973-05-10 | 1973-11-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1976-11-08 | 1977-05-10 | 1977-11-09 | $7700.00 | Window Closed / Lapsed |