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.