Electronic transport in composites based on polyaniline blended with cellulose acetate — a DC-Conductivity and ESR analysis

Polyaniline protonated with camphorsulphonic acid or di-i-octyl phosphate was blended with cellulose acetate to produce composites with remarkably low percolation thresholds. As for generalized variable range hopping their conductivity follows: σ=σ0e-(T0T)γ. For both systems the exponent γ systematically increases with dilution from γ - 0.5 at high concentrations to γ - 0.8 near the percolation threshold. As shown recently, electron spin resonance (ESR) probes the conductivity of polyaniline on a microscopic scale. ESR-results are consistent with metallic behavior near room temperature and show little influence of dilution on the microscopic conductivity.