Conductive polymer blends as electrochromic materials

Conductive polymer blends were prepared mixing conductive and insulating polymers and their electrochemical and electrochromic properties were studied. Depending on the insulator matrix used, these properties are not changed. Blend containing polyacrylonitrile and poly(o-methoxyaniline) doped with p-toluene sulfonic acid presents the same electrochemical and electrochromic behavior as the pure conducting polymer. Other blends studied were those obtained by combining poly(epichlorohydrin-co-ethylene oxide) with poly(o-methoxyaniline) and poly(4,4'-dipentoxy-2,2'-bithiophene). An electrochromic device using these polymer blends and a liquid electrolyte was assembled and presented Delta%T-620 (nm) = 56%. This contrast decreased after 300 double potential steps to 33%. (C) 1999 Elsevier Science Ltd. All rights reserved.