Patent US1634215A successfully refreshed from Google Patents.
Patent US3562221A successfully refreshed from Google Patents.
US3562221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Accelerating anionic polymerization of lactams
Assignee: BASF SE
•
Filing: 1968-01-15
•
Granted: 1971-02-09
•
Expires: 1988-01-15
Abstract
Abstract A PROCESS FOR ACCELERATING ANIONIC POLYMERIZATION OF LACTAMS IN THE PRESENCE OF ALKALINE POLYMERIZATION CATALYSTS AND ACTIVATORS AT FROM 80* TO 200*C. IN THE PRESENCE OR ABSENCE OF INERT SOLVENTS, IN WHICH N-(N'',N''-DIPHENYLCARBAMOYL)-LACTAMS HAVING FOUR TO THIRTEEN MEMBERS IN THE LACTAM RING ARE USED AS ACTIVATORS.
Inventors
- 👤 Adolf Steinhofer
- 👤 Helmut Doerfel
- 👤 Georg Falkenstein
- 👤 Wolfgang-Dieter Jeserich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:00
CPC Classifications
C; C08; C08G; C08G69/00; C08G69/02; C08G69/08; C08G69/14; C08G69/16; C08G69/18; C08G69/20
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1974-02-08 | 1974-08-10 | 1975-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-08 | 1978-08-10 | 1979-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-08 | 1982-08-10 | 1983-02-09 | $7700.00 | Window Closed / Lapsed |