POSITIVE TEMPERATURE-COEFFICIENT CHARACTERISTICS OF POLY(3-ALKYLTHIOPHENE)S

Poly(3-alkylthiophene)(P3AT) films were prepared by both electrochemic al and chemically oxidative polymerization methods, and their positive temperature coefficient(PTC) characteristics were investigated in the range from 0 to 200 degrees C. The change in the amount of tetrafluor oborate ion(BF4-) or iron(III) perchlorate(FeCl3) which were doped int o P3AT film was also estimated by infrared(IR) and ultraviolet(UV) spe ctrophotometry. It was found that the P3AT films chemically polymerize d at a low temperature had PTC characteristics, which was not affected by the dedoping involved in thermal treatment.