Surface modification of TiO₂ nanoparticles with biodegradable nanocellolose and synthesis of novel...

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.