Surface modification of TiO2 nanoparticles with biodegradable nanocellolose and synthesis of novel polyimide/cellulose/TiO2 membrane

In this paper, novel polyimide/cellulose/TiO2 bionanocomposites (PI/BNCs) were prepared via a simple and inexpensive ultrasonic irradiation process. PI was synthesized by direct polycondensation reaction of novel monomer dianhydride with 4-(2-(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropan-2-yl)benzenamine. Due to the high surface energy and tendency for agglomeration the surface of nanoparticles was modified with cellulose. PI/BNCs containing 5, 10, and 15% of cellulose/TiO2 (BNCs) were successfully fabricated through ultrasonic irradiation technique. The obtained PI/BNCs were characterized by Fourier transform-infrared (FT-IR) spectroscopy, thermogravimetry analysis, X-ray powder diffraction, field emission-scanning electron microscopy (FE-SEM), and transmission electron microscopy (TEM). Thermogravimetric analysis data indicated an increase thermal stability of the PI/BNC polymers in compared to the pure polymer. From TEM image of PI/BNCs it can be found that the surface modified TiO2 with diametric size of less than 50nm, uniformly dispersed in the obtained PI matrix. The results obtained from gas permeation experiments with a constant pressure setup indicated that adding cellulose/TiO2 to the polymeric membrane structure increased the permeability of the membranes.