摘要 |
The invention is a method for forming polymer composite films using a removable substrate comprising: (a) forming a first dispersion of a first perfluorinated polymer containing sites convertible to ion exchange groups dispersed in a first dispersant having: a boiling point less than about 110 DEG C.; a density of from about 1.55 to about 2.2; and a solubility parameter of from greater than about 7.1 to about 8.2 hildebrands; (b) depositing the first dispersion onto a first removable substrate; (c) heating the first dispersion at a temperature sufficient for form and fuse a first polymer film; (d) forming a second dispersion of a second perfluorinated polymer containing sites convertible to ion exchange groups and a second dispersant having: a boiling point less than about 110 DEG C.; a density of from about 1.55 to about 2.2; and a solubility parameter of from greater than about 7.1 to about 8.2 hildebrands; (e) depositing the second dispersion onto the first film; (f) heating the second dispersion for a time and at a temperature sufficient to form and fuse a second polymer film; (g) bonding the first film to the second film, thereby forming a composite film; and (h) removing the first substrate. Particularly preferred as a first and as a second dispersant is a compound represented by the general formula: XCF2-CYZX' wherein: X is selected from the group consisting of F, Cl, Br, and I; X' is selected from the group consisting of Cl, Br, and I; Y and Z are independently selected from the group consisting of H, F, Cl, Br, I and R'; R' is selected from the group of perfluoroalkyl radicals and chloroperfluoroalkyl radicals having from 1 to 6 carbon atoms. The most preferred first and second dispersant is 1,2-dibromotetrafluoroethane.
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