Formation of honeycomb structure in poly(N-vinylcarbazole)/cellulose triacetate composite films

Poly(N-vinylcarbazole) (PVK) composites containing different concentrations of cellulose triacetate (CTA) were synthesized through oxidative polymerization of N-vinylcarbazole with ferric chloride. Characterization and thermal stability of the synthesized composite were investigated using Fourier transform infrared (FTIR) and ultraviolet-visible (UV-Vis) spectroscopy, and thermogravimetric analysis (TGA), respectively. Surface morphology of the synthesized composites was studied using both scanning and transmission electron microscopy. Well-ordered porous films of the polymer composites were fabricated by evaporation of the composite solution dissolved in a volatile solvent under humid conditions. The PVK-CTA composite formed a highly well-ordered honeycomb pattern with the appropriate concentration of CTA in the absence of any kind of amphiphilic copolymer to stabilize the air-water interface. Findings of this study indicate that uniformly dispersed CTA is responsible for the stability of the air-water interface in the composite solution, thus enabling the formation of a highly ordered polymer film.