A series of electroactive aromatic polyamides with 4-(dimethylamino)triphenylamine [(NMe 2 )TPA] units in the backbone were prepared from a newly synthesized diamine monomer, 4,4′-diamino-4′′-(dimethylamino)triphenylamine, and various aromatic dicarboxylic acids via the phophorylation polyamidation reaction. These polyamides are readily soluble in many organic solvents and can be solution-cast into tough and amorphous films. They had useful levels of thermal stability associated with relatively high glass-transition temperatures (277-298 °C), 10% weight loss temperatures in excess of 500 °C, and char yields at 800 °C in nitrogen higher than 67%. The polymer films showed reversible electrochemical oxidation accompanied by strong color changes with high coloration efficiency, high contrast ratio, and rapid switching time. The optical transmittance change (∆%T) at 640 nm between the neutral state and the fully oxidized state is up to 88%, and the coloration efficiency is as high as ca. 261 cm 2 /C with high optical density change (δOD) up to 0.94. The polymers also displayed low ionization potentials as a result of their (NMe 2 )TPA moieties. Cyclic voltammograms of the polyamide films on the indium-tin oxide (ITO)-coated glass substrate exhibited a pair of reversible oxidation waves with very low onset potential of 0.35 V (vs Ag/AgCl) in acetonitrile solution.

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Two new pyrenylamine-based polyimides were prepared from the polycondensation reaction of N,N-di(4-aminophenyl)-1-aminopyrene with pyromellitic dianhydride (PMDA) or 1,4,5,8naphthalenetetracarboxylic dianhydride (NTDA). The polyimide derived from PMDA is soluble in hot N-methyl-2-pyrrolidone and can be solution-cast into a flexible and strong film. The polyimides showed high glass transition temperatures (T g > 364 C) and high thermal stability. Cyclic voltammetry studies revealed that these two polyimides were ambipolar; they showed well-defined and reversible redox couples during both p-and n-doping processes, together with multi-electrochromic behaviors. The polymer films also exhibited high coloration efficiency, high redox stability, and fast response time.

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