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ABSTRACT Two novel electropolymerizable monomers, namely 3,5-bis(4-diphenylaminobenzamido)- N-[4-(carbazol-9-yl)phenyl]benzamide ( 5) and 3,5-bis(4-diphenylaminobenzamido)- N-[4-(3,6-dimethoxycarbazol-9-yl)phenyl]benzamide ( 5-MeO), were synthesized, and their electrochemical properties were studied by cyclic voltammetry. The electron-withdrawing amide groups efficiently blocked the radical cations delocalization between the two terminal TPA groups, rendering the electropolymerization of the TPA groups feasible. The polymer electrodeposited from monomer 5 could be further crosslinked through electro-coupling of the carbazole groups, which showed both electrochromic and fluorescent properties (the emission of blue light (460 nm) in solid state). Both of the electro-generated polymer films derived from 5 and 5-MeO showed reversible electrochemical oxidation processes in the range of 0 − 1.4 V with strong color changes and high contrast ratios in the visible and NIR regions upon electro-oxidation. © 2016 The Authors. Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. 2016, 54, 2476-2485 [ABSTRACT FROM AUTHOR]

ABSTRACT Three series of aromatic polyimides with 4-(carbazol-9-yl)triphenylamine moieties were prepared from the polycondensation reactions of 4,4′-diamino-4″-(carbazol-9-yl) triphenylamine (1), 4,4′-diamino-4″-(3,6-di- tert-butylcarbazol-9-yl)triphenylamine ( t-Bu-1), and 4,4′-diamino-4″-(3,6-dimethoxycarbazol-9-yl)triphenylamine (MeO-1), respectively, with various commercially available tetracarboxylic dianhydrides. In addition to high thermal stability and good film-forming ability, the resulting polyimides exhibited an ambipolar electrochromic behavior. The polyimides based on t-Bu-1 and MeO-1 revealed higher redox-stability and enhanced electrochromic performance than the corresponding ones based on 1 because the active sites of their carbazole units are blocked with bulky t-butyl or electron-donating methoxy groups. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1172-1184 [ABSTRACT FROM AUTHOR]

ABSTRACT A novel triphenylamine (TPA)-containing bis(ether anhydride) monomer, namely 4,4′-bis(3,4-dicarboxyphenoxy)triphenylamine dianhydride, was synthesized and reacted with various aromatic diamines leading to a series of new poly(ether-imide)s (PEI). Most of these PEIs were soluble in organic solvents and could be easily solution cast into flexible and strong films. The polymer films exhibited good thermal stability with glass-transition temperatures in the range 211-299 °C. The polymer films exhibited reversible electrochemical processes and stable color changes (from transparent to navy blue) with high coloration efficiency and contrast ratio upon electro-oxidation. During the electrochemical oxidation process, a crosslinked polymer structure was developed due to the coupling reaction between the TPA radical cation moieties in the polymer chains. These polymers can be used to fabricate electrochromic devices with high coloration efficiency, high redox stability, and fast response time. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 825-838 [ABSTRACT FROM AUTHOR]

ABSTRACT New series aromatic polyamides with (carbazol-9-yl)triphenylamine units were synthesized from a newly synthesized diamine monomer, 4,4′-diamino-4″-(3,6-dimethoxycarbazol-9-yl) triphenylamine, and aromatic dicarboxylic acids via the phosphorylation polyamidation technique. These polyamides exhibit good solubility in many organic solvents and can be solution-cast into flexible and strong films with high thermal stability. They show well-defined and reversible redox couples during oxidative scanning, with a strong color change from colorless neutral form to yellowish green and blue oxidized forms at applied potentials scanning from 0.0 to 1.3 V. They show enhanced redox-stability and electrochromic performance as compared to the corresponding analogs without methoxy substituents on the active sites of the carbazole unit. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 272-286 [ABSTRACT FROM AUTHOR]

ABSTRACT A series of electroactive polyetherimides (PEIs) with triphenylamine (TPA) units were prepared from the polycondensation reactions of 4,4′-bis( p-aminophenoxy)triphenylamine with aromatic tetracarboxylic dianhydrides via a conventional two-step technique. The PEIs showed high thermal stability, with glass-transition temperatures of 234-282 °C and decomposition temperatures in excess of 500 °C. They showed well-defined and reversible redox couples during both p- and n-doping processes, together with multielectrochromic behaviors. These polymers exhibited enhanced redox-stability and electrochromic performance as compared with the corresponding analogs without the phenoxy spacer between the TPA and imide units. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2925-2938 [ABSTRACT FROM AUTHOR]

Abstract: A new class of electrochemically active polyimides with di-tert-butyl-substituted N,N,N′,N′-tetraphenyl-1,4-phenylenediamine units was prepared from N,N-bis(4-aminophenyl)-N′,N′-bis(4-tert-butylphenyl)-1,4-phenylenediamine and various aromatic tetracarboxylic dianhydrides via a conventional two-step procedure that included a ring-opening polyaddition to give poly(amic acid)s, followed by chemical or thermal cyclodehydration. Most of the polyimides are readily soluble in many organic solvents and can be solution-cast into tough and amorphous films. They had useful levels of thermal stability, with relatively high glass-transition temperatures (276–334°C), 10% weight-loss temperatures in excess of 500°C, and char yields at 800°C in nitrogen higher than 60%. Cyclic voltammograms of the polyimide films cast on the indium-tin oxide (ITO)-coated glass substrate exhibited two reversible oxidation redox couples at 0.70–0.74V and 1.05–1.08V vs. Ag/AgCl in acetonitrile solution. The polyimide films revealed excellent stability of electrochromic characteristics, with a color change from colorless or pale yellowish neutral form to green and blue oxidized forms at applied potentials ranging from 0.0 to 1.3V. These anodically coloring polymeric materials exhibited high optical contrast of percentage transmittance change (Δ%T) up to 44% at 413nm and 43% at 890nm for the green coloration, and 98% at 681nm for the blue coloration. After over 50 cyclic switches, the polymer films still exhibited good redox and electrochromic stability. [Copyright &y& Elsevier]