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ABSTRACT A diamine containing heterocyclic pyridine and unsymmetrical carbazole substituents, 4-(9-ethyl-3-carbazole)-2,6-bis(4-aminophenyl)pyridine ( CBAPP), was prepared for use in the synthesis of poly(pyridine-imide)s PI-1-8 by direct polycondensation with dianhydrides in N,N-dimethylacetamide (DMAc). The poly(pyridine-imide)s derived from the diamine are highly soluble in solvents such as N-Methyl-2-pyrrolidone (NMP) and DMAc at room temperature. Noncoplanar polyimide (PI-1) showed excellent solubility, high transparency, and high-performance mechanical properties. These polymers had relatively high glass transition temperatures and exhibited good thermal stability in both nitrogen ( Td10 > 470 °C) and air ( Td10 > 450 °C). The PI-3∼5 cannot form flexible and tough films due to the unsymmetrical carbazole moiety, rigid structure, and polar-polar interaction. However, through copolymerization technique these polymers (PI-6∼8) could be enhanced through the solubility, mechanical, and thermal properties. The optical properties included a strong orange fluorescence (540 nm) after protonation with acid. When the HCl concentration was increased, a new absorption band at approximately 350 nm appeared, and the intensity of the fluorescent peak at 380 nm observed in the neutral polymer solution decreased, along with the appearance of the new fluorescent peak at 540 nm. The poly(pyridine-imide)s presented here showed only slight fluorescence quenching in the presence of methanol. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 405-412 [ABSTRACT FROM AUTHOR]

A new diamine containing pyridineand carbazole groups was synthesizedvia a Chichibabin reaction and subsequent reduction; this compoundwas then used in the preparation of organo-soluble aramides (PA-a–i). The resultant polymers had high glass transitiontemperatures, which fell within the ranges of 271–287 °C,and Td10at 510–535 °C ina nitrogen atmosphere. The pristine PA-aexhibited themaximum value in the UV–vis absorption spectrum at 307 nm,and this value shifted to 394 nm after protonation by HCl. When theemission of the polymer in THF solution was observed, the intensityof the emission peak at 420 nm decreased and the intensity of a newemission peak at 552 nm increased as the acid concentration increased.Additionally, the color of the polymer solution changed from blueto yellow after protonation. The intensity of the emission at 552nm based on excimers increased as MeOH content increased. The colorof polymer films also changed irreversibly from yellow, which wasindicative of the neutral form, to a dark brown oxidized form duringthe application of bias voltages ranging from 0 to 1.6 V. [ABSTRACT FROM AUTHOR]

Abstract: An optically active, conjugated polymer bearing unsymmetric pendant carbazole chromophores was prepared via the Suzuki coupling of 9,9-dioctylfluorene-2,7-diboronic acid and a novel pyridine-containing compound. The polymer had a T g of 192°C and T d10 at 437°C under a nitrogen atmosphere and exhibited absorption bands at 320–400nm and displayed an additional absorption bands at 380–480nm after protonation with aq. HCl solution. The photoluminescence of the polymer shifted from 360–460nm to 460–560nm after protonation and the photoluminescence quantum yield of the polymer in THF solution was 0.88. The emission color of the polymer film changed from blue (439nm) to yellow (551nm) under an applied bias voltage of 2.5V. [Copyright &y& Elsevier]

A new diiodo monomer containing heterocyclic pyridine and carbazole groups was synthesized via Chichibabin reaction and used in the preparation of a conjugated polymer via Suzuki coupling approach. The conjugated polymer was highly soluble in common organic solvents such as NMP, THF, dichloromethane, chloroform, toluene, xylene, and benzene at room temperature. The polymer had high glass transition temperature at 191 °C and Td10 at 434 °C in nitrogen atmosphere. The pristine polymer exhibited the UV–vis maximum absorption at 355 nm and shifted to 420 nm after protonation. The emission of the polymer in THF solution changed from the blue region with maximum peak at 400 nm to the yellow region with maximum peak at 540 nm after protonated by HCl, and the intensity of emission depended on the concentration of acid. The polymer also showed electrochromic behavior under applied voltage. The emission color of the polymer film changed from blue (435 nm) to yellow (570 nm) when 2.5 V bias voltage was applied. The polymer also exhibited write‐once and read‐many‐times (WORM) polymer memory effect with tristable states. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 991–1002, 2009 [ABSTRACT FROM AUTHOR]