Effects of cellulose nanowhiskers on the properties of poly(vinyl alcohol)/graphene nanoplatelets nanocomposites

Cellulose nanowhisker (CNW) is a kind of ideal reinforcing filler due to its biodegradability and renewability together with superior mechanical properties. CNW hybridization with graphene nanoplatelet (GN) incorporated into poly(vinyl alcohol) (PVA) films were produced by ultrasonication mixing prior to solution casting. CNW showed positive effects on the PVA/GN composite films, which improved the dispersion of GN and refined GN by replacing partial GN with CNW in PVA/GN composite films. The addition of CNW effectively prevented the aggregation of GN in PVA matrices during the evaporation of water. Lateral size of GN is reduced by replacement of 0.1 and 0.4 wt% GN with an equivalent amount of CNW. The grain size of PVA decreased from 3.2 nm for PVA‐0.5%GN to 2.8–3.1 nm for PVA/CNW/GN composite films. Young's modulus, tensile strength, and elongation at break of PVA/GN composite films increased by 12%, 13%, and 150% when 0.1 wt% GN was replaced by CNW, respectively. The glass transition temperature moved from 30.6°C for pure PVA to 40.4°C for PVA/CNW/GN composite and the storage modulus of composite increased by 93%. With only 0.1%CNW addition, the swelling ratio of PVA‐0.5%GN composites decreased by 15% and the conductivity of PVA‐0.5%GN composites increase by 156%. The PVA‐based composite with improved water resistance and electrical conductivity are potential for functional applications in the industrial field. POLYM. COMPOS., 38:E98–E107, 2017. © 2015 Society of Plastics Engineers