Transparent and thermally stable improved poly (vinyl alcohol)/Cloisite Na+/ZnO hybrid nanocomposite films: Fabrication, morphology and surface properties

A series of poly(vinyl alcohol)/Cloisite Na+-Tyrosine/Zinc oxide (PVA/Cloisite Na+-Tyr/ZnO) bionanocomposites were prepared by dispersing ZnO nanoparticles in solution containing mixture of the PVA and modified Cloisite Na+. Structure of nanocomposite coatings was investigated by X-ray diffraction and Fourier-transform infrared spectroscopy. The thermal stability and optical properties of bionanocomposite were characterized by thermogravimetric analysis and UV–vis spectroscopy, respectively. The introduction of ZnO nanoparticles into PVA/Cloisite Na+-Tyr mixed solutions significantly increased the thermal stability of the obtained films. The results revealed that the high UV-shielding efficiency of the composites: for a film containing 6.0 wt% of ZnO nanocrystals, over 92% of UV light at wavelengths of 368 nm was absorbed while the optical transparency in the visible region was slightly below that of a PVA/Cloisite Na+-Tyr film.

Figure optionsDownload as PowerPoint slideHighlight
► PVA/Cloisite Na+-Tyr/ZnO hybrids were prepared via surface coating using ultrasonic method.
► PVA/Cloisite Na+-Tyr is a suitable host matrix since it is a transparent and rather thermally stable.
► The ZnO NPs have the best interaction with surface of organo-nanoclay and PVA via H-bonding.
► UV photons with wavelengths from 300 nm to 360 nm were efficiently absorbed by the nanocomposite films.
► The results revealed the high UV-shielding efficiency of the obtained bionanocomposites.