A new dialdehyde-containing silicon was prepared by a reaction of Williamson-type and structurally characterized. By its subsequent condensation with 2,5-bis(p-aminophenyl)-1,3,4-oxadiazole, a multifunctional polyazomethine-containing imine, phenylene, oxadiazole, ether, and carbosilane groups within the chain was prepared. The complexes of this polymer with Co(II), Cu(II), and Zn(II) ions formed on the basis of electron-donor ability of the oxadiazole and azomethine groups were prepared in a one-step approach by mixing the two precursors of polyazomethine (dialdehyde and diamine) with corresponding metal salt. The ligand and metal complexes were characterized by spectral (Fourier transform infrared (FTIR), 1 H, and 13 C NMR) methods. The thermal, optical, electrochemical, and dielectric properties were studied and the effects of the metal insertion in dependence on its nature over these properties were evaluated. All compounds are soluble in common organic solvents and show low glass transitions due to the flexible ether and Si-C bonds, are fluorescent, mainly due to the oxadiazole ring, are redox active and have high dielectric constant due to the presence of oxadiazole, azomethine metal units.

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The ability to form multi-colored oxidation states upon applied positive potentials, and the narrow band gap of 2,7-substituted carbazole derivatives, had encouraged the development of new carbazole containing polymers with interesting optoelectronic properties. Four conjugated polymers containing substituted carbazole units spaced in the main chain by vinylene and 1,4-phenyleneethynylene segments were synthesized via Stille and Sonogashira coupling reactions. Two different substitution positions of carbazole, such as 2,7- and 3,6-carbazole were used to tune the conjugation length and the charge transfer properties of the resulting polymers. The structures of the obtained polymers were characterized by Fourier transform infrared spectroscopy and proton nuclear magnetic resonance spectroscopy while the electronic and optical properties were investigated as function of carbazole substitution positions or spacer nature by ultraviolet-visible spectroscopy and cyclic voltammetry. The redox behaviour of polymers as films deposited on working electrode was investigated using cyclic voltammetry technique, and the lowest unoccupied molecular orbital and highest unoccupied molecular orbital energy levels values were also determined. Spectroelectrochemical measurements suggested the existence of polaronic and bipolaronic structures of polymers backbones accompanied by multi-electrochromic behavior.