Patent US3711442A successfully refreshed from Google Patents.
US3711442A
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Polymers with silylurea units which can be converted into polyurea elastomers
Assignee: Rhone Poulenc SA
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Filing: 1970-05-28
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Granted: 1973-01-16
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Expires: 1990-05-28
Abstract
Abstract POLYSILYLUREAS HAVING REPEAT UNITS OF GENERAL FORMULA: (O-A-O-CO-NH-B-NH-CO)M, AND -(N(-R4)-D-N(-R5)-CO-N(-SI(-R1)(-R2)(-R3))-B-N(-SI(-R1) (-R2)(-R3))-CO)N- WHEREIN N AND M ARE 20-400, A, B AND D ARE DIVALENT ALIPHATIC OR AROMATIC RADICALS, R1, R2 AND R3 ARE ALKYL AND R4 AND R5 ARE ALKYL OR TOGETHER ARE ALKYLENE; ARE PREPARED BY REACTING A(OH)2 WITH AN EXCESS OF OCN-B-NCO TO GIVE A POLYMER WHICH IS REACTED UNDER ANHYDROUS CONDITIONS WITH AN N,N''-BIS-TRIORGANOSILYL DIAMINE R4-N(-SI(-R1)(-R2)(-R3))-D-N(-SI(-R1)(-R2)(-R3))-R5 THE POLYSILYLUREAS ARE SOLUBLE IN ORGANIC SOLVENTS AND ARE FORMED INTO FILMS OR FILAMENTS AND HYDROLYSED TO CORRESPONDING POLYUREAS.
Inventors
- 👤 M Lefort
- 👤 J Robin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 13:10
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/83; C08G18/831; C08G18/832; C08G18/08; C08G18/10
Claims Analysis
Total Claims: 0
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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) | 1976-01-16 | 1976-07-17 | 1977-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-16 | 1980-07-17 | 1981-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-16 | 1984-07-17 | 1985-01-16 | $7700.00 | Window Closed / Lapsed |