Catalytic oxidative polymerization of thiophene derivatives

The oxidative polymerization of thiophene derivatives was carried out using palladium (II) acetate as a catalyst in combination with copper (II) acetate and trifluoroacetic acid under an oxygen atmosphere. The poly(3-hexylthiophene) (P3HT) obtained through palladium-catalyzed polymerization exhibited a richer head-to-head content than authentic P3HT prepared using a conventional oxidant, and the maximum absorption and luminescence wavelengths of the P3HT were blue-shifted to 338 and 534 nm in the ultraviolet and photoluminesce spectra, respectively. The palladium-catalyzed oxidative polymerization process was applied to 3,4-disubstituted thiophene monomers. 3,4-Ethylenedioxythiophene in aqueous media was also polymerized using poly(styrenesulfonic acid). The oxidative polymerization mechanism in the palladium system is discussed. Polymer Journal (2013) 45, 281-286; doi:10.1038/pj.2012.146; published online 25 July 2012