Patent US3734978A successfully refreshed from Google Patents.
US3734978A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Blocking polystyrene produced by anionic slurry polymerization
Assignee: Mobil Oil AS
•
Filing: 1971-05-12
•
Granted: 1973-05-22
•
Expires: 1991-05-12
Abstract
Abstract THERE IS PROVIDED A BLOCKING PROCESS FOR POLYSTRENE IN WHICH A STYRENE MONOMER IS INITIALLY POLYMERIZED SLURRIED IN A PARAFFINIC OR MONOOLEFIN SLURRYING MEDIUM, USING AN ANIONIC INITIATOR AND A STYRENE-ALKYLSTYRENE BLOCK POLYMER DISPERSANT, A DIVINYL-BENZENE MODIFYING AGENT IS ADDED ANIONICALLY TO MODIFY THE POLYSTYRENE, AND THE MODIFIED POLYSTYRENE IS BLOCKING WITH A MONOMER POLYERIZABLE WITH A FREE RADICAL INITIATOR, A ZIEGLER-NATTA COORDINATION CATALYST, OR A CATIONIC INITIATOR.
Inventors
- 👤 F Schwab
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 02:09
CPC Classifications
C; C08; C08F; C08F297/00; C08F297/02; C08F12/00; C08F12/02; C08F12/04; C08F12/06; C08F12/08; C08F257/00; C08F257/02
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) | 1976-05-21 | 1976-11-20 | 1977-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-05-21 | 1980-11-20 | 1981-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-05-21 | 1984-11-20 | 1985-05-22 | $7700.00 | Window Closed / Lapsed |