Preparation of graphene/poly(vinyl alcohol) nanocomposites with enhanced mechanical properties and water resistance

The control and dispersal of graphene nanosheets in polymer hosts are challenges in the development of high-performance graphene-based nanocomposites due to the strong interlayer cohesive energy and surface inertia. Here we report a simple and practical approach to synthesize graphene-reinforced poly(vinyl alcohol) (PVA) composite films by incorporating graphene oxide and graphene into PVA aqueous solution. The resulting nanocomposites revealed increases of up to 212% in tensile strength and 34% in elongation at break with only 0.5 wt% graphene content. Water absorption measurements showed that the water absorption ratio of the graphene/PVA composites decreased from 105.2 to 48.8%, and the barrier properties were obviously improved. Contact angle measurements showed that the composites were hydrophobic (theta > 90 degrees) in contrast to the highly hydrophilic (theta < 90 degrees) pure PVA. (C) 2011 Society of Chemical Industry