Electrical properties of polypyrrole doped with β-naphthalenesulfonicacid and polypyrrole–polymethyl methacrylate blends

The electrical conductivity both dc and ac of polypyrrole doped with β-naphthalenesulfonicacid (NSA) and polypyrrole–polymethyl methacrylate blends have been investigated in the temperature range of 300–80 K and in the frequency range of 100–10 MHz. Samples are prepared by in situ polymerisation technique using the common solvent meta cresol. The frequency dependence of conductivity satisfies the power law, <F>σ(ω)∝ωs</F>, with <F>s=0.73</F>–0.95. In PPY–NSA, <F>s</F> is independent of temperature and explained by electron tunneling model whereas in PPY(NSA)–PMMA blend <F>s</F> decreases with temperature and the ac mechanism is predicted by the overlapping polaron tunneling. The ac conductivity <F>σ(ω)</F> as a function of temperature follows the scaling law, <F>σ(ω)/σ0=1+(ω/ω0)n</F> with <F>n≃0.85</F>. [Copyright &y& Elsevier]