Characterization and electrical properties of polyvinyl alcohol based polymer electrolyte films doped with ammonium thiocyanate

In this communication, films of polyvinyl alcohol (PVA) polymer complexed with ammonium thiocyanate (NH4SCN) salt were studied. XRD (X-ray diffraction) was used to study the complexation of salt with the polymer matrix and amorphicity in the films. DSC (differential scanning calorimetry) studies showed that the glass transition temperatures (Tg) of the PVA:NH4SCN complexed films were less than pristine PVA. Raman analysis was analyzed in order to study the change in the vibrational bands due to the complexation of salt with PVA. Optical micrographs confirm the fractal formation in 75:25 and 70:30 PVA:NH4SCN films. Ionic transference number was estimated by Wagner's polarization method and its large value indicates that conduction takes place mainly due to mobile ionic species. Maximum conductivity ∼10−3 S/cm at room temperature was obtained for 70:30 ratio of PVA: NH4SCN polymer electrolyte films.