US3594333A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Formylated aromatic polymers and method of making same
Assignee: University of California Berkeley
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Filing: 1967-07-26
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Granted: 1971-07-20
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Expires: 1987-07-26
Abstract
Abstract CROSSLINKED, FORMAYLATED, SWELLABLE, AROMATIC-CONTAINING POLYMERS PERPARED BY SWELLING A PREEXISTING CROSSLINKED POLYMER WITH AN INERT ORGANIC SOLVENT, REACTING THE POLYMER WITH A DIHALOMETHYL ALKYL ETHER IN THE PRESENCE OF A MILD FRIEDEL-CRAFTS CATALYST AND HYDROLYZING THE REACTION PRODUCT. THE RESULTING FORMYLATED POLYMER RETAINS ITS SWELLING CHARACTERISTICS AND IS USEFUL AS AN INTERMEDIATE IN THE SYNTHESIS OF OPTICALLY ACTIVE AMINE-CONTAINING SORBENTS.
Inventors
- 👤 David R Buss
- 👤 Theodore Vermeulen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:43
CPC Classifications
C; C08; C08F; C08F8/00
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) | 1974-07-19 | 1975-01-18 | 1975-07-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-19 | 1979-01-18 | 1979-07-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-19 | 1983-01-18 | 1983-07-20 | $7700.00 | Window Closed / Lapsed |