Processible, environmentally stable, highly conductive forms of polythiophene

As electronic materials, the most promising synthetic semiconductors and metals for practical large scale applications are those which can combine convenient processibility with high environmental stability, good mechanical properties, and high conductivity. Missing from the desired combination of properties for the majority of interesting conductive polymers is convenient processibility. A series of solution processible poly(3-alkylthiophenes) are described which form highly conductive, environmentally stable complexes with electron acceptors. These materials are quite unusual in that, in addition to their attractive properties, conductivities are generally high and surprisingly insensitive to the length of the alkyl substituents. © 1987.