▎ 摘　　要

In this study, poly(vinyl alcohol) (PVA)-graphite oxide and PVA-graphene oxide (XGO) films were prepared by simple and environmentally friendly method. Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscope revealed the strong hydrogen-bonding interactions between XGO and PVA matrix and the layered structure of tensile fracture surfaces of exfoliated PVA-XGO films. These resulted in a remarkable improvement on mechanical and barrier properties of XGO/PVA nanocomposite films. The addition of 0.3 and 2.0wt.% XGO showed an increase in tensile strength (49%) and failure stain (13-22%), in comparison with the neat PVA films. The dramatic improvement of 144% in elastic modulus was observed in PVA/2.0wt.% XGO. Both O-2 and water vapour permeability coefficients of PVA film decreased by about 76% and 21% at an XGO loading of 2.0wt.%, respectively. Preliminary test was performed to determine the use of nanocomposite films to extend the shelf life of bananas. It was found that bananas packaged in nanocomposite films were ripened slower than those unpackaged or packaged in PVA films. These results demonstrate that such films could dramatically promote the application of PVA-based films in the packaging industry. Copyright (c) 2015 John Wiley & Sons, Ltd.