Preparation and Characterization of New Soluble and Thermally Stable Polyazomethine by Polycondensation of Thiophene-2,5-dicarboxaldehyde and Ortho-tolidine for Optoelectronics

In recent years, there has been considerable interest in conducting polymeric materials containing conjugated bonds. Imine polymers, in which nitrogen atoms are incorporated into the conjugated system, offer a different approach to the formation of materials with equally interesting electronic and optical properties due to the –CH=N– group being isoelectronic with the –CH=CH– group. In this study, a polyazomethine copolymer was prepared by a polycondensation reaction using ortho-tolidine and thiophene-2,5-dicarboxaldehyde catalyzed by Maghnite H+. The effect of time, temperature, amount of Maghnite H+, and solvent on the produced copolymer material was investigated. The optical, structural, and morphological properties of the copolymer, as well as the size of the particles, were investigated using various techniques, including ¹H NMR and FTIR spectroscopy, thermogravimetric analysis, scanning electron microscopy, X‑ray diffraction, and UV–Vis absorption. The optical band gap value was found to be around 2.54 eV.