Novel carbazole–pyridine copolymers by an economical method: synthesis, spectroscopic and thermochemical studies

The synthesis, as well as spectroscopic and thermochemical studies of a novel class of carbazole-4-phenylpyridine co-polymers are described. The synthesis was carried out by a simple and cheaper method compared to the lengthy methods usually adopted for the preparation of carbazole–pyridine copolymers which involve costly catalysts. Thus, two series of polymers were synthesized by a modified Chichibabin reaction, i.e., by the condensation of diacetylated N-alkylcarbazoles with 3-substituted benzaldehydes in the presence of ammonium acetate in refluxing acetic acid. All the polymers were characterized by FTIR, (1)H NMR, (13)C NMR, UV–vis spectroscopy, fluorimetry, TGA and DSC. The weight average molecular masses (M(w)) of the polymers were estimated by the laser light scattering (LLS) technique.