PREPARATION AND ELECTRICAL-CONDUCTIVITY OF LANGMUIR-BLODGETT-FILMS OFPOLY(3-ALKYLTHIOPHENE)S

Five poly (3-alkylthiophene)s (P3ATs) with different alkyl side chains were synthesized. Pure P3ATs alone are not well suited for manipulati on by the Langmuir-Blodgett (LB) technique, but their mixed systems wi th arachidic acid can be used to prepare high-quality Y-type films wit h the vertical dipping method, which was proved by UV-visible spectra and small-angle X-ray diffraction patterns. Conductivities of the LB f ilms were measured using a two-probe method at room temperature. The c onductivities exhibited obvious anisotropy and could increase by 2-4 o rders of magnitude after iodine vapor doping. The influence of alkyl c hain length on the conductivity in the LB films was revealed. (C) 1998 John Wiley & Sons, Inc.