Optical, electrochemical, and thermal behavior of polybenzoxazine copolymers incorporated with tetraphenylimidazole and diphenylquinoline

Two new polybenzoxazine copolymers were synthesized by polymerizing conventional benzoxazine monomer with varying weight percentage of tetraphenylimidazole and diphenylquinoline. The tetrasubstituted imidazole was synthesized through Debus-Radziszewski imidazole synthesis method, and quinoline derivative was synthesized through Friedlander quinoline synthesis, and their structure was confirmed through FTIR, (HNMR)-H-1, and MASS spectral analysis. New polybenzoxazine copolymers were synthesized by polymerizing conventional benzoxazine monomer with varying weight percentage of (10, 20, and 30%) of phenolic tetraphenylimidazole and diphenylquinoline. The polybenzoxazines cocured with 10, 20, and 30wt% of imidazole derivative showed a band gap of 2.27, 2.08, and 2.2eV, respectively, and the quinoline derivative incorporated at 10, 20, and 30wt% in to polybenzoxazines exhibited a band gap of 2.26, 2.3, and 2.03eV, respectively. The polybenzoxazines cocured with phenolic imidazoles and quinolines have high glass transition and thermal degradation stability in addition to significant improvement in optical and electrochemical properties than that of conventional bisphenol-based polybenzoxazines.