Red, Green, and Blue Electrochromism in Ambipolar Poly(amine-amide-imide)s Based on Electroactive Tetraphenyl-p-Phenylenediamine Units

A series of novel poly(amine-amide-imide)s (PAAIs) based on tetraphenyl-p-phenylenediamine (TPPA) units showing anodically/cathodically electrochromic characteristic with three primary colors [red, green, and blue (RGB)] were prepared from the direct polycondensation of the TPPA-based diamine monomer with various aromatic bis(trimellitimide)s. These multicolored electrochromic polymers were readily soluble in polar organic solvents and showed excellent thermal stability associated with high glass-transition temperatures (288-314 degrees C) and high-char yield (higher than 60% at 800 degrees C in nitrogen). The PAAI films revealed electrochemical oxidation and reduction accompanied with high contrast of optical transmittance color changes from the pale yellow neutral state to the green/blue oxidized state and red reduced state, respectively. The electrochromic films had high-coloration efficiency (CE = 178 and 242 cm(2)/C at the first and the second stages, respectively), low-switching time, and good redox stability, which still retained a high electroactivity after long-term redox cycles. (C) 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 4747-4757, 2010