Preparation and physical properties of (PVA)0.75(NH4Br)0.25(H2SO4)xM solid acid membrane

Abstract In this work, solid acid membrane consisting of poly(vinyl alcohol) (PVA), ammonium bromide (NH 4 Br) and sulfuric acid (SA) has been prepared by a solution casting technique method. X-ray diffraction of the (PVA) 0.75 (NH 4 Br) 0.25 (H 2 SO 4 ) xM polymer matrix and pure (PVA) 0.75 (NH 4 Br) 0.25 revealed the difference in crystallinity between them. The effect of different amounts of SA on the conductivity of the polymer electrolytes was studied. The ionic conductivity of the prepared electrolytes can reach 3.1 × 10 −2 S cm −1 at room temperature. The conductivity measurements carried out at different temperatures indicate that all the films follow Arrhenius behavior and that the activation energy decreases with the increase in SA concentration. The a.c. conductivity seems to follow the universal power law.