PAA/imidazol-based proton conducting polymer electrolytes

Anhydrous proton conducting polymer electrolytes have been prepared by entrapping imidazol (Im) in polyacrylic acid (PAA) with various stoichiometric ratios, x, to form PAAxIm (x is the number of moles of Im per polymer repeat unit). Polymer electrolytes, PAAxIm (with x=0.5 and 1) can be cast into transparent, homogeneous films. FT-IR results indicate the protonation of imidazol. Thermogravimetric analysis (TG) illustrates that these blends are chemically stable up to about 160 °C. Differential scanning calorimetry (DSC) shows that glass transition temperature decrease from 57 °C for x=0.5 to 35 °C for x=1. The dc conductivity increases with x and temperature reaching not, vert, similar10−3 S/cm for x=1 at 120 °C.