Enhanced interfacial interaction for effective reinforcement of poly(vinyl alcohol) nanocomposites at low loading of graphene

The graphene/poly(vinyl alcohol) (PVA) nancomposites with homogeneous dispersion of the nanosheet and enhanced nanofiller–matrix interfacial interaction were fabricated via water blending partially reduced graphene oxide and PVA. The nanocomposites were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and thermogravimetry. The graphene nanosheets were fully exfoliated in the PVA matrix and a new covalent linkage was formed between graphene and PVA matrix. Uncommon to conventional method, the enhanced interfacial adhesion resulted from covalent interaction and hydrogen bondings between graphene and PVA backbone. The mechanical and thermal properties of the nanocomposites were significantly improved at low graphene loadings. An 116% increase in tensile strength and a 19 °C improvement of onset thermal degradation temperature were achieved by the addition of only 0.8 wt% graphene.