▎ 摘　　要

Biopolymer nanocomposite films were prepared by adding exfoliated graphene oxide nanosheets (GOn) into carboxymethyl cellulose (CMC) at low and high GOn loadings (0.4-7 wt %). As firstly evidenced by viscosity of film-forming solutions, microscopic observations and infrared spectroscopy measurements, it was found that the GOn form a three-dimensional network throughout strong interfacial interactions with CMC, confirming that the GOn were well dispersed within the CMC, even at high GOn content, owing to the presence of several multifunctional groups on both phases which ensured the high compatibility between them. The topography of as prepared films was characterized by atomic force microscopy measurements showing that the films have a smooth surface with a very low average roughness for all range of GOn contents. Furthermore, the thermal stability, glass transition temperature, and tensile properties of nanocomposite films were gradually increased with increasing of GOn contents. By adding 7 wt % GOn, 18% increases of thermal stability, 17% of glass transition temperature, 623% of Young's modulus, and 268% of tensile strength were achieved. This work produced structured CMC-based nanocomposite films containing low and high loadings of welldispersed GOn. The high performances of these films can be expected to have potential in biomaterials or packaging materials applications. (C) 2015 Wiley Periodicals, Inc.