Modification of Clay with L-Leucine and TiO2 with Silane Coupling Agent for Preparation of Poly(Vinyl Alcohol)/Organo-Nanoclay/Modified TiO2 Nanocomposites Film

Poly(vinyl alcohol)/organo-nanoclay/modified-TiO2 nanocomposites films were fabricated by dispersion of modified TiO2 on the surface of organo-nanoclay in a poly(vinyl alcohol) matrix via an ultrasonic process followed by solution film casting. For this purpose surface-modified TiO2 nano-particles were added into the poly(vinyl alcohol)/organo-modified Cloisite Na+ nanocomposites matrix with 10 wt% organonanoclay. For the improvement of nanoparticles dispersion and increasing possible interactions between nano-particles and polymeric matrix, the surface of the nano-TiO2 was modified with silane coupling agent (KH550). Also, the negative charge on the silica layer can play an important role in dispersing nanosized TiO2. Three nanocomposites with different loading of modified-TiO2 (1, 3 and 6 wt%) were prepared and characterized by X-ray diffraction, Fourier transform infrared spectroscopy, field emission type scanning electron microscope, scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis and UV-Vis transmission spectra. In morphological images it was observed that the OMMT was dispersed homogeneously in PVA matrix and modified TiO2 nanoparticles are regularly dispersed on whole surface of organo-nanoclay layers. TGA results show that thermal stability of poly(vinyl alcohol)/organoclay/ modified TiO2 nanocomposites are enhanced compared with neat PVA. (C) Koninklijke Brill NV, Leiden, 2012