Conducting polymers of octanoic acid 2-thiophen-3-yl-ethyl ester and their electrochromic properties

Octanoic acid 2-thiophen-3-yl-ethyl ester was synthesized via the reaction of 3-thiophene ethanol with octanoyl chloride. The resulting monomer was electrochemically homopolymerized in the presence of tetrabutylammonium tetrafluoroborate as the supporting electrolyte, in the acetonitrile/borontrifluoride ethyl ether solvent system. The resulting polymer was characterized using various experimental techniques. Spectroelectrochemistry analysis of the homopolymer reflects electronic transitions at 434, approximate to 800 and 1100 nm, revealing pi-pi degrees transition, polaron and bipolaron band formation, respectively, leading to esthetically pleasing color changes between transmissive yellow and blue, with reasonable switching times. (c) 2005 Elsevier B.V. All rights reserved.