Mixed Membrane Matrices Based on Nafion/UiO-66/SOH-UiO-66 Nano-MOFs: Revealing the Effect of Crystal Size, Sulfonation, and Filler Loading on the Mechanical and Conductivity Properties.

Mixed membrane matrices (MMMs) made up with Nafion and nanocrystals of zirconium metal-organic framework (MOF) UiO-66 or the analogous sulfonated SOH-UiO-66 were prepared by varying the filler loading and the size of the crystals. The combined effects of size and loading, together with the presence of sulfonic groups covalently linked to the MOFs, were studied with regard to the conductivity and mechanical properties of the obtained composite matrices. A large screening of membranes was preliminarily made and, on the most promising samples, an accurate conductivity study at different relative humidities and temperatures was also carried out.

Low-Permeability Poly(ether Ether Ketone)-Based Ampholytic Membranes.

Ion-exchange membranes based on sulfonated and sulfaminated poly(ether ether ketone) were prepared by a modified sulfamination route. In a first step, poly(ether ether ketone) was sulfonated. The sulfonic acid groups were then transformed into chlorosulfonic moieties by reaction with thionyl chloride.