Patent US1775531A successfully refreshed from Google Patents.
Patent US3583937A successfully refreshed from Google Patents.
US3583937A
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Process of preparing polyurethane-polyurea compositions having free isocyanate groups
Assignee: Wyandotte Chemicals Corp
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Filing: 1968-09-09
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Granted: 1971-06-08
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Expires: 1988-09-09
Abstract
Abstract A LINEAR URETHANE-UEA POLYMER HAVING A HIGH NUMBER OF FUNCTIONAL ISOCYANATE GROUPS IS PREPARED BY CHAIN EXTENDING AN ISOCYANATE-TERMINATED DIOL PREPOLYMER WITH A BLEND OF PRIMARY DIAMINES AND DIFUNCTIONAL CHAIN EXTENDERS, AND THEN FURTHER REACTING THIS RESULTING PRODUCT WITH AN ORGANIC DI- OR POLYISOCYANATE. THE REACTION CONDITIONS ARE SUCH THAT ONLY ONE ISOCYANATE GROUP OF EACH DI- OR POLYISOCYANATE MOLECULE IS REACTED WITH THE CHAINEXTENDED PRODUCT.
Inventors
- 👤 Adolfas Damusis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 11:31
CPC Classifications
C; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/10
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) | 1974-06-07 | 1974-12-07 | 1975-06-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-06-07 | 1978-12-07 | 1979-06-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-07 | 1982-12-07 | 1983-06-08 | $7700.00 | Window Closed / Lapsed |