Investigation of structural and thermal properties of distinct nanofillers-doped PVA composite films

Purpose of present study was to investigate the effect of different nanofillers doping on structural and thermal properties of poly(vinyl alcohol) (PVA)-based nanocomposite films. Herein, ZnO nanoparticles (NPs), CuO NPs, graphene oxide and reduced graphene oxide (RGO) nanosheets have been used as separate nanofillers in the formation of PVA nanocomposite films via solution casting approach. The prepared composite films were characterized using X-ray diffraction, scanning electron microscopy, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, differential scanning calorimetry and tensile strength testing. The results demonstrate the effect of various nanofillers on glass transition temperature (T_g), melting temperature (T_m), crystallization temperature (T_c), percentage crystallinity (%χ_c) and tensile strength of composite films. A doping with (0.02 wt%) RGO nanosheets caused significant influence on thermal properties and tensile strength of PVA composite films as compared to other test nanofillers. The doping with RGO nanosheets resulted in elevation of T_g (48.2 °C), T_m (218.3 °C), T_c (157.8 °C) and %χ_c (41.9%) as compared to that of pure PVA (T_g 38.4 °C, T_m 190.4 °C, T_c 115.1 °C and %χ_c 22.2%). Overall, the doping of PVA with graphene-based nanosheets exhibited better tensile strength and thermal stability of nanocomposite as compared with other tested nanofillers.