A new carbazole-derived triphenylamine-containing aromatic dicarboxylic acid monomer, 4,4′dicarboxy-4′′-N-carbazolyltriphenylamine, with blue light (460 nm) fluorescence quantum yield of 40% was successfully synthesized by the cesium-fluoride-mediated condensation of N-(4-aminophenyl)carbazole with 4-fluorobenzonitrile, followed by alkaline hydrolysis of the dinitrile intermediate. A series of novel poly(amineamide)s with pendent N-phenylcarbazole units having inherent viscosities of 0.36-0.61 dL/g were prepared from the newly synthesized dicarboxylic acid monomer and various aromatic diamines by direct phosphorylation polycondensation. The obtained polymers were amorphous and could afford flexible, transparent, and tough films with good mechanical properties. They had useful levels of thermal stability associated with relatively high glasstransition temperatures (269-322 °C). These polymers exhibited strong UV-vis absorption maxima at 340-361 nm, and their photoluminescence showed emission peaks around 449-465 nm with quantum yields up to 46% in NMP solution. The hole-transporting and electrochromic properties were examined by electrochemical and spectroelectrochemical methods. Cyclic voltammograms of the poly(amine-amide) films prepared by casting polymer solution onto an indium-tin oxide (ITO)-coated glass substrate exhibited one reversible oxidative redox couples at potentials of 1.11-1.18 V vs Ag/AgCl in acetonitrile solution due to oxidation of main-chain triphenylamine unit. The polymer films revealed excellent stability of electrochromic characteristics for the radical cations generated, changing color from original yellowish to deep blue.

Three methacrylate-containing polyimides (Px-MMA; x = 1-3) were prepared from the esterification of hydroxyl-containing polyimides (Px-OH; x = 1-3) with methacrylic anhydride. Px-MMA exhibits active ester linkages (Ph-O-C(=O)-) that can react with epoxy in the presence of 4-dimethylaminopyridine (DMAP), so Px-MMA acted as a curing agent for a dicyclopentadiene-phenol epoxy (HP7200) to prepare epoxy thermosets (Px-MMA/HP7200; x = 1-3) thermosets. For property comparisons, P1-OH/HP7200 thermosets were also prepared. The reaction between active ester and epoxy results in an ester linkage, which is less polar than secondary alcohol resulting from the reaction between phenolic OH and epoxy, so P1-MMA/HP7200 are more hydrophobic and exhibit better dielectric properties than P1-OH/HP7200. The double bond of methacrylate can cure at higher temperatures, leading to epoxy thermosets with a high-T g and moderate-to-low dielectric properties.

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A series of organosoluble, aromatic polyamides were synthesized from a 4methyl-substituted, triphenylamine-containing, aromatic diacid monomer, 4,4 0 -dicarboxy-4 00 -methyltriphenylamine, which is a blue-light (454-nm) emitter with a fluorescence quantum efficiency of 46%. These triphenylamine-based, high-performance polymers had strong fluorescence emissions in the blue region with high quantum yields up to 64% and one reversible oxidation redox couple around 1.20 V versus Ag/AgCl in acetonitrile solutions. They exhibited good thermal stability, with 10% weight loss temperatures above 480 8C under a nitrogen atmosphere and with relatively high glass-transition temperatures (252-309 8C). All the polyamides revealed excellent stability of electrochromic characteristics, changing color from the original pale yellow to blue. V V C 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4095-4107, 2006 Figure 15. Potential step absorptometry of polyamide 3e (in CH 3 CN with 0.1 M TBAP as the supporting electrolyte) by the application of a potential step: (a) 0 V $ 0.70 V), (b) 0 V $ 1.01 V), and (c) 0 V $ 1.40 V.4106