摘要 |
A process is provided for making a liquid composition of a perfluorinated polymer having sulfonic acid or sulfonate groups in a liquid medium by contacting the polymer with a mixture of 25 to 100% by weight of water and 0 to 75% by weight of a second liquid component such as a lower alcohol, e.g., propanol or methanol, at a temperature of at least 180 DEG C. (at least 240 DEG C. when about 90% to 100% water is used), in a closed system. The liquid composition made by this process, or modified liquid products prepared therefrom, are used in coating various substrates, in casting films, and in repairing perfluorinated ion exchange films and membranes. The process is also useful in recovering perfluorinated polymer having sulfonic acid or sulfonate groups from scraps and used articles made of such polymer or containing such polymer as a component part thereof.
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