Simultaneous Reinforcement and Toughening of Carbon Nanotube/Cellulose Conductive Nanocomposite Films by Interfacial Hydrogen Bonding

Abstract

Carbon nanotube (CNT)/cellulose nanocomposite films were prepared by a featured processing method, i.e., solution dispersion, slow gelation and hot-press drying, where an environmentally benign processing solvent (sodium hydroxide/urea aqueous solution) was used. The scanning electron microscopy and transmission electron microscopy demonstrated uniform CNT dispersion in the cellulose. The slow gelation and hot-press drying could effectively reduce the free volume and force the cellulose chains and CNTs to contact as close as possible, thus forming the strong interfacial hydrogen bonding between the residual oxygen-containing functional groups on the CNT surfaces and the hydroxyl groups in the cellulose chains, as confirmed by X-ray photoelectron spectroscopy and Fourier transformation infrared spectroscopy results. As a result, with a CNT loading of 5 wt %, the tensile strength and Young’s modulus of the cellulose nanocomposite films were increased by 55% and 21% relative to neat cellulose film. More inte...