Electric conductivity of poly(3-dodecylthiophene) and its dependence on the conformational changes of polymer chains

The influence of the heat-induced conformational changes in side alkyls and in the backbone of poly(3-dodecylthiophene) (PDDT) with a higher content o f configurational head-to-head defects (39%) on electric conductivity was s tudied. It has been found that conformational changes affect the electric c onductivity values of PDDT doped with FeCl3 which attain at 0.021 mol of Fe /mol dodecylthiophene more than 10(8) Sm-1 within the whole temperature ran ge (from 78 up to 320 K). For the analysis of conformational changes the en tropy temperature dependence was calculated from the experimental data on t he specific heat capacity. In this paper dependences between the resistance and the conformational changes of PDDT were discussed.