Thermoelectric Properties of Poly(3-Alkylthiophenes)

Abstract:

Typical conductive polymers of poly(3-alkylthiophenes) were synthesized by oxidative polymerization. Alkyl side chains were CnH2n+1 with n=4, 6, 8, 12. The regioregularity with the HT linkage was larger than 99% based on NMR analysis. Completely regioregular head-to-tail (HT) poly(3-alkylthiophenes) were obtained. We have evaluated the effect of side chain size on the thermoelectric properties of Seebeck coefficient and electrical conductivity. The results were as follows: 1) Seebeck coefficient decreased with an increasing electrical conductivity. 2) High Seebeck coefficient >1mV/K was observed at low electrical conductivity <10-2S/cm. 3) The small side chain caused the higher electrical conductivity in the range of electrical conductivity <10- 1S/cm.

• Periodical: Materials Science Forum (Volumes 492-493)
• Pages: 141-144
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.492-493.141
• Online since: August 2005
• Authors: Yoshikazu Shinohara, K. Ohara, Hachiro Nakanishi, Yoshio Imai, Yukihiro Isoda
• Keywords: Conductive Polymer, Electrical Conductivity, Head-To-Tail, Poly(3-Alkylthiophenes), Seebeck Coefficient

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