Electrical and optical properties of polyaniline polyvinyl alcohol composite films

Polyaniline polyvinyl alcohol (PANI-PVA) composite films have been prepared chemically in inorganic acid medium at different ratios of their monomer units. A homogeneous blend can be obtained even using inorganic acid medium by terminating the reaction soon after the mixture attains homogeneous colour change. The SEM pictures show that the films have well formed grains with approximate sizes ranging from 0.3 to 1.2 mu m. The results show definite dependence of various parameters on the PANI-PVA ratio in the blend. The XRD spectra show increase in crystallinity in the films with increase of PVA concentration. The FTIR spectra show some peaks, which ascertain chemical interlinking of PANT and PVA in these blends. The studies of electrical conductivity of these films through measurement of current-voltage (I-V) characteristics show non-ohmic power law behaviour (I alpha V-n) with power (n) lying in the range 0.22 to 0.88. The conductivity value of these films is found to be between 1.80 to 0.9 S cm(-1).