Ayşe Aslan

Preparation, Properties, and Characterization of Polymer Electrolyte Membranes Based on Poly(1-vinyl-1,2,4 triazole) and Poly(styrene sulfonic acid)

A class of polymer electrolyte membranes was produced by the combination of poly(1-vinyl-1,2,4 triazole) (PVTri) and poly(styrene sulfonic acid) (PSSA) at several stoichiometric ratios with respect to the molar ratio of polymer repeating units. PVTri was synthesized by free-radical polymerization of the monomer, 1-vinyl-1,2,4-triazole, and PSSA was produced from polystyrene by direct sulfonation. The proton-exchange reaction, which resulted in complexation between polymers, was illustrated by Fourier transform infrared spectroscopy. Thermogravimetric analysis showed that the membranes are thermally stable up to approximately 250°C. The existence of single glass-transition temperatures of the polymer electrolytes was shown by differential scanning calorimetry. The scanning electron microscopy results also demonstrated the homogeneity of the materials. The electrochemical stability of the materials was studied by cyclic voltammetry. Proton conductivities of the anhydrous samples were measured using impedance spectroscopy. Under an anhydrous state, maximum proton conductivities of PVTriP(SSA) 4 and PVTriP(SSA) 2 membranes were measured as 0.015 at 150°C and 0.033 S/cm at 120°C, respectively.

As an Alternative Membrane: Functional NanoParticles/Polymer Composites Membranes for Proton Exchange Membrane Fuel Cells (PEMFC)

Novel proton conducting nanocomposite membranes included binary and ternary mixtures of acid modified nanotitania particles particles with polymers such as poly (vinyl alcohol) (PVA),pol (vinyl phosphonic acid), sulfonated polysulfone (SPSU) and poly (1-vinyl 1,2,4-triazole) (PVTri) . The interaction of functional nanoparticles with the host matrix were searched by FT-IR spectroscopy. The homogeneous distribution of functional nanoparticles in the membranes was confirmed by SEM micrographs. The spectroscopic measurements and water/methanol uptake studies suggested a complexation between polymers and sulphonic acid that inhibited the leaching out of acidic units. The TGA results verified that the presence of modified nanoparticles in the composite membranes the thermel stability of the membranes enhanced up to above 200 °C.