US3560450A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lactone polymerization process with particulate initiator
Assignee: Shell USA Inc
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Filing: 1968-12-23
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Granted: 1971-02-02
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Expires: 1988-12-23
Abstract
Abstract AN IMPROVED PROCESS FOR THE SLURRY POLYMERIZATION OF ONE OR MORE B-PROPIOLACTONES, AT LEAST 50% MOLE BEING PIVALOLACTONE, IN A LIQUID HYDROCARBON DILUENT IN THE PRESENCE OF A SOLID CARBOXYLATE ANION CONTAINING INITIATOR WHICH IS EITHER A PREFORMED BETAINE OR A "LIVING" PREPOLYMER, AT LEAST 80% BY WEIGHT OF THE INITIATOR POSSESSING A PARTICLE SIZE BETWEEN 5 AND 200 MICRONS.
Inventors
- 👤 Dario P Curotti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:48
CPC Classifications
C; C08; C08G; C08G63/00; 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) | 1974-02-01 | 1974-08-03 | 1975-02-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-01 | 1978-08-03 | 1979-02-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-01 | 1982-08-03 | 1983-02-02 | $7700.00 | Window Closed / Lapsed |