Investigation of the Coupled Effect of Liquid and Solid Inorganic Additives on Thermal Stability and Water Retention of PFSA Composite

Here, investigation of the high-temperature water retention property of new composites, which contain perfluorosulfonic acid (PFSA) polymer as matrix, a mineral acid, and MgF2 nanoparticles as inorganic additives, is done based on structural analysis. The composite shows an improvement in the water removal temperature from 50 to 250 °C because the crystalline water molecules were attached on the surface of solid inorganic additives at 250 °C. To optimize the water retention property, the 1 wt % of sulfuric acid and 3–15 wt % of MgF2-coated glass particles in PFSA polymer composites as additives were investigated. From the Fourier transform infrared-attenuated total reflection studies of these composite membranes, two major phenomena related to structural details of PFSA polymer as a function of the polymer and the weight ratio of the solid additives are observed: (1) sulfonic acid group released the proton even with low humidity and (2) the conformation and/or the degree of the crystallinity of the poly(t...