Claims
- 1. A process for making an ion exchange membrane or film comprising
- (a) selecting a solvent from the group consisting of (i) a perfluorinated cycloalkane, (ii) perfluorinated aromatic compounds, or (iii) perfluorotrialkylamines; said solvent having a critical temperature of greater than about 150.degree. C.;
- (b) dissolving the alkyl ester form of a carboxylic fluorinated polymer having an equivalent weight of more than about 900 and containing tetrafluoroethylene units in said solvent to form a solution; and
- (c) spray coating a reinforcing fabric to form an ion exchange membrane.
- 2. The process as recited in claim 1 wherein said polymer is a perfluorinated cycloalkane substituted with one or more perfluoroalkyl or perfluoroalkylene groups.
- 3. The process as recited in claim 1 wherein said polymer contains the side chain OCF.sub.2 CF(CF.sub.3)OCF.sub.2 CF.sub.2 COOCH.sub.3.
- 4. The process as recited in claim 1 wherein said solvent is perfluorotetradecahydrophenanthrene, perfluoromethylcyclohexane, perfluoro decalin, hexafluorobenzene or perfluorotrihexylamine.
- 5. The process as recited in claim 1 wherein said solvent is perfluorotetradecahydrophenanthrene.
- 6. A process for repairing an ion exchange membrane or film comprising applying a composition to said ion exchange membrane or film, the composition comprising a solution of a carboxylic fluorinated polymer having an equivalent weight of more than about 900 and containing tetrafluoroethylene units, or a blend of such carboxylic fluorinated polymer with a sulfonic fluorinated polymer, and a solvent which is selected from the group consisting of (i) a perfluorinated cycloalkane, (ii) perfluorinated aromatic compounds, or (iii) perfluorotrialkylamine, said solvent having a critical temperature of greater than about 150.degree. C.
Parent Case Info
This is a continuation of application Ser. No. 07/935,350, filed Aug. 28, 1992, now U.S. Pat. No. 5,273,694, patented Dec. 28, 1993.
US Referenced Citations (14)
Non-Patent Literature Citations (7)
Entry |
Article "Solubility Characteristics of Perfluorinated Polymers with Sulfonyl Fluoride Functionality" by G. H. McCain and M. J. Covitch, J. Electrochem. Soc.: Electrochemical Science and Technology (Jun. 1984) pp. 1350-1352. |
Abstract of Japan 55-79048 (Published Jun., 1980). |
Abstract of Japan 55-149336 (Published Nov., 1980). |
Abstract of Japan 57-182345 (Published Nov., 1982). |
Abstract of Japan 57-182346 (Published Nov., 1982). |
Abstract of Japan 57-185337 (Published Nov., 1982). |
Abstract of Japan 63-286442 (Published Nov., 1988). |
Continuations (1)
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Number |
Date |
Country |
Parent |
935350 |
Aug 1992 |
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