Poly(3-dodecylthiophenes) polymerized with different amounts of catalyst

The effect of the amount of the catalyst FeCl3, used during the direct oxid ation polymerization, on the structure and properties of the obtained poly( 3-dodecylthiophene) (P3DDT) was investigated in this paper. Such measuremen ts as gel permeation chromatography (GPC), nuclear magnetic resonance (NMR) spectroscopy, thermal analysis, X-ray diffraction, infrared spectroscopy ( FTIR) and ultraviolet-visible (W-vis) spectroscopy were applied. It is foun d that a suitable addition of FeCl3 can contribute to generate a P3DDT with greater percentage of head-to-tail head-to-tail (HT-HT) linkages, which ar e generally favored. The reduction of the other linkage defects helps to le ngthen conjugation length, thus leading to more orderly chain packing. (C) 2000 Elsevier Science S.A. All rights reserved.