Synthesis, characterization and quantum yields of multichromic poly(azomethine)s containing carbazole unit

Abstract

Poly(azomethine)s containing phosphor, silane and carbazole were synthesized with multiple stage and examined through different photophysical, electrochemical, and thermal behaviours. Following substances were synthesized as an initial step: N-hexyl-carbazole (CH) and N-hexyl-carbazolaldehyde (CHDA), via elimination reaction in argon media and N-hexyl-carbazole azomethine (CHA) via condensation reaction of CHDA with 4-aminophenol also poly(azomethine)s (P-Si-CHA, P-P-CHA) containing silane and phosphor via elimination reaction. The structures of synthesized compounds were confirmed by Fourier-transform infrared spectroscopy (FT-IR), Ultraviolet–visible spectroscopy (UV–Vis) and nuclear magnetic resonance spectroscopy (NMR). Electrochemical properties of compounds were examined with cyclic voltammetry (CV) technique. Fluorescence measurements were utilized to investigate the photochemical behaviors by photoluminescence (PL) analysis. CHA compound surprisingly presented multicolor emission behavior (when excited at 370, 420, 480, 540 and 580 nm, the solution emitted blue, green, yellow, orange and red lights, respectively) with relatively high quantum yield (19.9%) in DMF solvent. Additionally, thermal behaviors of all compounds were determined by TG and DSC techniques. Surface morphologies of polymers were imaged with scanning electron microscope (SEM).