Syntheses of novel copolymers containing carbazole and their electrochromic properties

In this work, the compounds 2,5-bis(3,6-di(thiophen-3-yl)-9H-carbazol-9-yl)thiophene (2) and 1,4-bis[(3,6-di(thiophen-3-yl)-9H-carbazol-9-yl)methyl]benzene (4) were synthesized via Ullmann and Suzuki coupling reactions. Additionally, the homopolymers and copolymers of these compounds with thiophene (Th), 3,4-ethylenedioxythiophene (EDOT) and pyrrole (Py) were synthesized and coated onto an indium tin oxide (ITO) surface via electrochemical oxidative polymerization. The spectroelectrochemical and electrochromic properties of these compounds were also investigated. The switching ability of these copolymers was measured as the percent transmittance (T%) at their point of maximum contrast point. Structural characterizations of the compounds were performed by FT-IR and X-ray Photoelectron Spectroscopy (XPS). The morphologic properties of the copolymers were determined by Scanning Electron Microscopy (SEM).