Perfluorocarboxylic acid membrane water content

Water Content. Figure 4 shows the relation between the water content of perfluorocarboxylic acid membrane prepared by chemical treatment and the ion exchange capacity with varying external solution concentration. As the concentration of the external solution increases, the membrane shrinkage increases and the water content is therefore decreased. The influence of... 

Water content in Figure 4 can be expressed as a function of ion exchange capacity and external solution concentration by the following empirical equation, which is similar to that proposed for perfluorosulfonic acid membranes by W.G.F. Grot in 1972 (44). The water content of perfluorocarboxylic acid membrane is much lower than that of perfluorosulfonic acid membrane. 

The water content of a perfluoro sulfonic acid membrane and a perfluorocarboxylic acid membrane illustrated in Fig. 18 clearly... 

Figure 18. Water content, equivalent weight, and concentration of NaOH of perfluorocarboxylic and perfluorosul-fonic acid membranes (reproduced with permission from the authors).

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