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    Conducting copolymers of thiophene functionalized polystyrenes with thiophene
    (Elsevier Science Sa, 2005) Sahin, E; Camurlu, P; Toppare, L; Mercore, VM; Cianga, I; Yagci, Y
    Thiophene capped polystyrenes (TCP1, TCP2) were synthesized by atom transfer radical polymerization of styrene followed by Suzuki condensation with 2-thiophene boronic acid. Electrically conducting graft polymers of TCP1 and TCP2 with thiophene were achieved by electrochemical methods. Characterization of the graft polymers were performed by cyclic voltammetry (CV), Fourier transform infrared spectroscopy, differential scanning calorimetry, scanning electron microscopy analyses. Electrochromic properties of the conducting copolymers were investigated by spectroelectrochemistry, kinetic and colorimetry studies. The observed lambda(max) and band gap values were found to be at 432 nm, 2.10 eV and 453 nm, 2.13 eV for P(TCP1 -co-Th) and P(TCP2-co-Th), respectively. Also, we successfully established the utilization of dual-type complementary colored polymer electrochromic devices using P(TCP I co-Th)/poly(3,4-ethylenedioxythiophene) (PEDOT) in sandwich configuration. The switching ability, stability and optical memory of the electrochromic device were investigated with UV-Vis spectrophotometer and CV. P(TCP1-co-Th)/PEDOT switches between blue and brown. (c) 2005 Elsevier B.V. All rights reserved.
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    Synthesis, characterization and electrochromic properties of a conducting copolymer of pyrrole functionalized polystyrene with pyrrole
    (Elsevier Sci Ltd, 2006) Tarkuc, S; Sahin, E; Toppare, L; Colak, D; Cianga, I; Yagci, Y
    A well-defined polystyrene (PSt) based polymer containing at one end-chain 3.5-dibromobenzene moiety. prepared by atom transfer radical polymerization (ATRP), was modified in two reaction steps. First one constitutes a Suzuki coupling reaction between aromatic dibromine functional polymer and 3-aminophenylboronic acid, when a diamino-containing intermediate was obtained. The second step is a condensation reaction between the diamino functional polystyrene and 2-pyrrole alclehyde. Thus, a polymer containing a conjugated sequence having pyrollyl groups at the extremities was synthesized. The presence of oxidable pyrrole groups in the structure of the polymer permitted further electropolymerization. The structures of intermediate polymers were analyzed by spectral methods (H-1 NMR, FTIR). Electrochemical copolymerization of pyrrole functionalized polymer (PStPy) with pyrrole was carried out in acetonitrile (ACN)-tetrabutylammonium tetrafluoroborate (TBAFB) solvent electrolyte Couple. Characterization of the resulting copolymer were performed via Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC). scanning electron microscopy (SEM), spectroclectrochemical analysis, and kinetic study. Spectroelectrochemical analysis show that the copolymer of PStPy with Py has an electronic band gap (due to pi-pi* transition) of 2.4 eV at 393 nm, with a yellow color in the fully reduced form and a blue color in the fully oxidized form. Via kinetic studies. the optical contrast %Delta T was found to be 20% for P(PStPy-co-Py). Results showed that the time required to reach 95% of the ultimate T was 1.7 s for the P(PStPy-co-Py). (c) 2006 Elsevier Ltd. All rights reserved.