Two new monomers, 2-benzyl-5,12-dihydro-2H-pyrrolo[3 0 ,4 0 :2,3][1,4]dioxocino [6,7-b]quinoxaline (DPOQ) and 5,12-dihydrothieno[3 0 ,4 0 :2,3][1,4]dithiocino[6,7-b]quinoxaline (DTTQ), were synthesized. The chemical structures of the monomers were characterized by nuclear magnetic resonance ( 1 H NMR), Fourier transform infrared (FTIR) and mass spectra. Copolymer of DPOQ with bithiophene (BT) was synthesized via potentiostatic electrochemical polymerization in acetonitrile-tetrabutylammonium tetrafluoroborate solventelectrolyte couple. For DTTQ, copolymerization with bithiophene was achieved via potentiodynamic method in dichloromethane-tetrabutylammonium hexafluorophosphate solvent-electrolyte couple. Characterizations of the resulting copolymers were performed by cyclic voltammetry (CV), FTIR, scanning electron microscopy (SEM) and UV-Vis spectroscopy. Four-probe technique was used to measure the conductivities of the samples. Moreover, the spectroelectrochemical and electrochromic properties of the copolymer films were investigated. In addition, dual type polymer electrochromic devices based on P(DPOQ-co-BT) and P(DTTQ-co-BT) with poly(3,4-ethylenedioxythiophene) were constructed. Spectroelectrochemistry, electrochromic switching and open circuit stability of the devices were studied. They were found to have good switching times, reasonable contrasts and optical memories.

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In this study, the electropolymerization of ethyl and methyl substituted asymmetrical nitrogen analogs of 3,4-ethylenedioxythiophene (OEt and OMe) were synthesized, characterized and their electrochemical properties were investigated. Both polymers (POEt and POMe) were synthesized electrochemically and characterized using spectroelectrochemical technique to determine optical changes of the resulting polymer films. Electrochemical studies demonstrated that these polymers exhibited a significantly low oxidation potential compared to their analogs reported in the literature. These polymers also provided a low optical bandgap with good optical contrasts. Furthermore, multi-electrochromic properties upon different applied potentials revealed that these polymers have potential applications in electrochromic devices. As a further characterization, their dual type electrochromic devices were constructed with poly(2,2,6,6-tetramethylpiperidinyloxy-4-yl methacrylate) (PTMA) which is transmissive in its both redox states. Devices were characterized via electrochemical and spectroelectrochemical techniques.