US4053498A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Perfluoroalkylene ether-imidate and -thioimidate esters
Assignee: United States Department of the Air Force
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Filing: 1976-07-30
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Granted: 1977-10-11
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Expires: 1996-07-30
Abstract
Abstract Hexafluoropropylene oxide-terminated perfluoroalkylene ether-imidate and -thioimidate esters are prepared by the reaction of certain perfluoroalkylene ether dinitriles with trifluoroethanol or ethanethiol. The compounds are useful as monomers in synthesizing thermooxidatively stable, low glass transition temperature perfluoroalkylene ether bibenzoxazole polymers with improved hydrolytic stability properties.
Inventors
- 👤 Robert C. Evers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 00:50
CPC Classifications
C; C08; C08G; C08G73/00; C08G73/06; C08G73/22
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
32 words
A compound having the following formula: ##STR11## wherein X is SC 2 H 5 or OCH 2 CF 3 ; and R f ' is ##STR12## where m+n equals 4 or 5.
Claim 2
Dependent Claim
32 words
A compound having the following formula: ##STR11## wherein X is SC 2 H 5 or OCH 2 CF 3 ; and R f ' is ##STR12## where m+n equals 4 or 5.
Claim 3
Dependent Claim
9 words
A mixture of compounds having the following formulas: ##STR13##
Claim 4
Dependent Claim
9 words
A mixture of compounds having the following formulas: ##STR13##
Claim 5
Dependent Claim
16 words
The compound according to claim 1 in which X is SC 2 H 5 and ##STR14##
Claim 6
Dependent Claim
16 words
The compound according to claim 1 in which X is OCH 2 CF 3 and ##STR15##
Claim 7
Dependent Claim
17 words
The mixture of compounds according to claim 2 in which X is SC 2 H 5 .
Claim 8
Dependent Claim
17 words
The mixture of compounds according to claim 2 in which X is OCH 2 CF 3 .
References Cited (Backward Citations)
US3112334A
Cited
DE2426913A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-10 | 1981-04-11 | 1981-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-10 | 1985-04-11 | 1985-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-10 | 1989-04-11 | 1989-10-11 | $7700.00 | Window Closed / Lapsed |