Simple synthesis of conducting poly(2-aminothiazole) with high molecular weight

Chemical and electrochemical oxidative polymerizations are the most used methods to synthesize conducting polymers such as polyaniline, polypyrrole, and polythiophene. However, a significant generic problem for these methods is that a high amount of oxidants or electrolytes are needed, which are usually difficult to be removed. Here we report a simple synthesis of conducting poly(2-aminothiazole) (P2AT) in nitromethane (CH 3 NO 2 ) using ferric chloride (FeCl 3 ) as an oxidant at a low amount (could be as low as 1 mol%, related to 2-aminothiazole). The effects of reaction temperature, reaction time, and FeCl 3 concentration on the yield of polymerization were systematically investigated. The P2ATs were fully characterized by FT-IR, 1 H NMR, UV-vis, gel permeation chromatograms (GPC), and thermogravimetric analysis (TGA). Optimization of the synthetic conditions allows P2AT with both high yield (53 %) and thermal stability (62 % of residue at 600 °C) to be achieved simultaneously. Possible polymerization mechanism was also proposed. Four-probe conductivity measurement indicated that the P2AT exhibited good semi-conductive property with tunable values of 10 −5 –10 −3 S/cm upon iodine (I 2 ) doping. Simple synthesis of P2AT using a low amount of FeCl 3 would be a very promising protocol to expand conducting polymer family.