Composite Membranes Based on Functionalized Mesostructured Cellular Foam Particles and Sulfonated Poly(Ether Ether Sulfone) with Potential Application in Fuel Cells

Composite polymeric membranes were designed based on sulfonated poly(ether ether sulfone) (sPEES) and mesostructured cellular foam (MCF) silica nanoparticles functionalized with organic compounds. Parameters such as molecular weight (MW) of the polymer, nature of the functional group of the MCF silica, and percentage of silica charge were evaluated on the final properties of the membranes. Composite membrane characterization was carried out on their water retention capacity (high MW polymer between 20–46% and for the low MW between 20–60%), ion exchange capacity (IEC) (high MW polymer between 0.02 mmol/g–0.07 mmol/g and low MW between 0.03–0.09 mmol/g) and proton conductivity (high MW polymer molecular between 15–70 mS/cm and low MW between 0.1–150 mS/cm). Finally, the membrane prepared with the low molecular weight polymer and 3% wt. of functionalized silica with sulfonic groups exhibited results similar to Nafion(®) 117.