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 phosph ate was blended with cellulose acetate to produce composites with rema rkably low percolation thresholds. As for generalized variable range h opping their conductivity follows: sigma = sigma(0)e(-(T0/T)gamma). Fo r both systems the exponent gamma systematically increases with diluti on from gamma similar or equal to 0.5 at high concentrations to gamma similar or equal to 0.8 near the percolation threshold. As shown recen tly, electron spin resonance (ESR) probes the conductivity of polyanil ine on a microscopic scale. ESR-results are consistent with metallic b ehavior near room temperature and show little influence of dilution on the microscopic conductivity.