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US3960814A
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Poly (perfluoroalkylene oxide) oxadiazoles and their synthesis
Assignee: United States Department of the Air Force
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Filing: 1975-02-27
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Granted: 1976-06-01
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Expires: 1995-02-27
Abstract
Abstract A perfluoroalkylene oxide dinitrile, an aromatic dinitrile N-oxide and an aromatic trinitrile are terpolymerized to obtain a poly(perfluoroalkylene oxide) oxadiazole containing pendent aromatic nitrile groups. The fluorinated polymer product can be cured with a polyfunctional nitrile N-oxide to provide elastomers that are particularly useful in aircraft applications involving use temperatures ranging from about -70 DEG F to about 400 DEG F. For example, the elastomers can be employed as fuel tank sealants, coatings, O-ring seals, diaphragms, and the like.
Inventors
- 👤 Robert E. Cochoy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:13
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/32; C08G65/329; C08G65/333; C08G65/33365; C08G65/3332; C08G73/00; C08G73/06; C08G73/08
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
95 words
A poly(perfluoroalkylene oxide)oxadiazole consisting essentially of repeating units having the following structural formula: R f -X-R-X-R f -x(-R-X ##SPC3##X) a -R-X, where R f is --CF 2 (OCF 2 CF 2 ) m --O--(CF 2 ) 5 --O--(CF 2 CF 2 O) n --CF 2 --, in which m and n are each an integer equal to at least 1 and the sum of m and n is in the range of 2 to 12, inclusive; where x is ##EQU3## where R is ##SPC4## and where a is in the range of 0.04 to 1.0.
Claim 2
Dependent Claim
95 words
A poly(perfluoroalkylene oxide)oxadiazole consisting essentially of repeating units having the following structural formula: R f -X-R-X-R f -x(-R-X ##SPC3##X) a -R-X, where R f is --CF 2 (OCF 2 CF 2 ) m --O--(CF 2 ) 5 --O--(CF 2 CF 2 O) n --CF 2 --, in which m and n are each an integer equal to at least 1 and the sum of m and n is in the range of 2 to 12, inclusive; where x is ##EQU3## where R is ##SPC4## and where a is in the range of 0.04 to 1.0.
Claim 3
Dependent Claim
11 words
The poly(perfluoroalkylene oxide)oxadiazole of claim 1 in which R is ##SPC5##
Claim 4
Dependent Claim
11 words
The poly(perfluoroalkylene oxide)oxadiazole of claim 1 in which R is ##SPC6##
Claim 5
Dependent Claim
11 words
The poly(perfluoroalkylene oxide)oxadiazole of claim 1 in which R is ##SPC7##
Claim 6
Dependent Claim
11 words
The poly(perfluoroalkylene oxide)oxadiazole of claim 1 in which R is ##SPC8##
Claim 7
Dependent Claim
11 words
The poly(perfluoroalkylene oxide)oxadiazole of claim 1 in which R is ##SPC9##
Claim 8
Dependent Claim
90 words
A process for synthesizing a poly(perfluoroalkylenes oxide)oxadiazole which comprises the steps of (1) adding to a reaction zone an aromatic dinitrile N-oxide; a perfluoroalkylene oxide dinitrile; 1,3,5-tricyanobenzene; and a fluorinated solvent in which the 1,3,5-tricyanobenzene is insoluble; (2) after the aromatic dinitrile N-oxide and the perfluoroalkylene oxide dinitrile have reacted with one another to form a polymeric material, adding to the reaction zone a solvent, misicible with the fluorinated solvent, in which the 1,3,5-tricyanobenzene is soluble; and (3) reacting the 1,3,5-tricyanobenzene with the polymeric material, thereby forming a terpolymer product.
Claim 9
Dependent Claim
90 words
A process for synthesizing a poly(perfluoroalkylenes oxide)oxadiazole which comprises the steps of (1) adding to a reaction zone an aromatic dinitrile N-oxide; a perfluoroalkylene oxide dinitrile; 1,3,5-tricyanobenzene; and a fluorinated solvent in which the 1,3,5-tricyanobenzene is insoluble; (2) after the aromatic dinitrile N-oxide and the perfluoroalkylene oxide dinitrile have reacted with one another to form a polymeric material, adding to the reaction zone a solvent, misicible with the fluorinated solvent, in which the 1,3,5-tricyanobenzene is soluble; and (3) reacting the 1,3,5-tricyanobenzene with the polymeric material, thereby forming a terpolymer product.
Claim 10
Dependent Claim
74 words
The process according to claim 7 in which the aromatic dinitrile N-oxide and the perfluoroalkylene oxide dinitrile are reacted at a temperature in the range of about 10° to 35°C for a period of about 3 to 8 days; the 1,3.5-tricyanobenzene and the polymeric material are reacted at a temperature in the range of about 10° to 35°C; and the total reaction time for the two reactions ranges from about 4 to 13 days.
Claim 11
Dependent Claim
68 words
The process according to claim 8 in which the perfluoroalkylene oxide dinitrile has the following formula: Nc CF 2 (OCF 2 CF 2 ) m --O--(CF 2 ) 5 --(CF 2 CF 2 O) n --CF 2 CN, in which m and n are each an integer equal to at least 1 and the sum of m and n is in the range of 2 to 12, inclusive.
Claim 12
Dependent Claim
27 words
The process according to claim 9 in which the aromatic dinitrile N-oxide is N,N'-terephthalonitrile oxide; isophthalo-bis-(nitrile N-oxide); 1,5-naphthalene-bis(nitrile N-oxide); 4,4'-biphenyl-bis(nitrile N-oxide); 4'-benzonitrile oxide sulfone; or 4,4'-oxybis(phenylnitrile N-oxide).
Claim 13
Dependent Claim
28 words
The process according to claim 10 in which the fluorinated solvent is trichlorotrifluoroethane, dichlorotetrafluoroethane, chloropentafluoroethane, or hexafluoroethane and the solvent for 1,3,5-tricyanobenzene is methylene chloride, chloroform, or trichloroethane.
Claim 14
Dependent Claim
55 words
The process according to claim 11 in which the amount of 1,3,5-tricyanobenzene constitutes about 1 to 80 mole percent of the total amount of 1,3,5-tricyanobenzene and perfluoroalkylene oxide dinitrile and the mole ratio of the amount of aromatic dinitrile N-oxide to the amount of 1,3,5-tricyanobenzene and perfluoroalkylene oxide dinitrile ranges from about 1 to 1.25.
Claim 15
Dependent Claim
59 words
The process according to claim 12 in which the terpolymer product is blended with 0.5 to 10 weight percent of a bis(nitrile oxide), based upon the weight of the terpolymer; the resulting blend is heated at a temperature ranging from about 100° to 300°F for a period of about 10 to 60 minutes; and a cured product is recovered.
Claim 16
Dependent Claim
14 words
The process according to claim 13 in which the bis(nitrile oxide) is N,N'-terephthalonitrile dioxide.
References Cited (Backward Citations)
US3317484A
Cited
GB1073324A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-06-01 | 1979-12-01 | 1980-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-01 | 1983-12-01 | 1984-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-01 | 1987-12-01 | 1988-06-01 | $7700.00 | Window Closed / Lapsed |