Patent US3575914A successfully refreshed from Google Patents.
US3575914A
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Polymeric materials which are the reaction product of (a) a primary polyamine and (b) a polycarboxylic anhydride which is the thermal condensation product of (1) an aromatic intramolecular carboxylic anhydride (2) aromatic polysulfonyl halide (3) other aromatics
Assignee: Monsanto Chemicals Ltd
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Filing: 1968-01-29
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Granted: 1971-04-20
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Expires: 1988-01-29
Abstract
Abstract DISCLOSED HEREIN ARE POLYMERIC MATERIALS CHARACTERIZED BY HAVING A PLURALITY OF RECURRING IMIDE LINKAGES AND DIRECT LINKAGES BETWEEN AROMATIC NUCLEI. THESE MATERIALS ARE THE POLYMERIC REACTION PRODUCT OF (1) A POLYCARBOXYLIC ANHYDRIDE WHICH IS THE THERMAL CONDENSATION PRODUCT OF (A) AN AROMATIC POLYSULPHONYL HALIDE, (B) AN AROMATIC INTRAMOLECULAR CARBOXYLIC ANHYDRIDE, AND (C) A THIRD AROMATIC COMPOUND; AND (2) A POLYAMINE HAVING AT LEAST TWO PRIMARY AMINO GROUPS PER MOLECULE.
Inventors
- 👤 Frank Long
- 👤 Gordon Roy Ensor
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:36
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/10; C08G73/1003; C08G69/00; C08G69/02; C08G69/26; C08G69/32; C08G73/1067
Claims Analysis
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-04-19 | 1974-10-19 | 1975-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-04-19 | 1978-10-19 | 1979-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-04-19 | 1982-10-19 | 1983-04-20 | $7700.00 | Window Closed / Lapsed |