US3720651A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of manufacturing a copolymer of a c4 olefin with maleic anhydride
Assignee: Kuraray Co Ltd
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Filing: 1971-04-09
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Granted: 1973-03-13
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Expires: 1991-04-09
Abstract
Abstract A METHOD OF MANUFACTURING A COPOLYMER OF A C4 OLEFIN WITH MALEIC ANHYDRIDE IS PROVIDED COMPRISING COPOLYMERIZING AN OLEFIN SELECTED FROM THE GROUP CONSISTING OF ISOBUTENE AND A MIXTURE OF ISOBUTENE AND OTHER HYDROCARBONS WHICH CONTAIN 4 CARBON ATOMS WITH MALEIC ANHYDRIDE IN A SOLVENT CONTAINING AT LEAST 80 WEIGHT PERCENT OF ISOPROPYL ACETATE OR A MIXTURE OF ETHYL ACETATE AND TERT-BUTANOL.
Inventors
- 👤 H Nakamoto
- 👤 H Tanaka
- 👤 S Imoto
- 👤 O Ohara
- 👤 R Ueeda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 12:39
CPC Classifications
C; C08; C08F; C08F22/00; C08F22/04; C08F10/00
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) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |