RELATIONSHIP BETWEEN CONDUCTIVITY AND REDOX POTENTIAL OF PYRROLE-BASED AND THIOPHENE-BASED POLYCONJUGATED POLYMERS

Conductivity-sigma and redox potential E0 for 20 pyrrole- and seven thiophene-based polymers reported in the literature are correlated. A linear relationship between ln-sigma and E0 is obeyed with slope -16 V-1 for both classes and x-axis intercept 0.05 V and 0.7 V versus SCE for pyrrole- and thiophene-based polymers, respectively. The relationship is explained according to simple theoretical arguments and analysed on the basis of existing models for conducting polymers. Experimental and predicted conductivities for new pyrrole- and thiophene-based polymers agree within one order of magnitude.