▎ 摘　　要

Network formation of graphene oxide (GO) nanoplatelets was held accountable for the modification of the rheological properties of nanocomposites based on poly(3-hydroxybutyrate) (PHB). The nanocomposites were prepared by a casting procedure from the green solvent gamma-butyrolactone. The nature of the GO network and percolation limits were analyzed by making use of the molar mass reduction of PHB that takes place in the melt, as well as by studying the deformation dependence of the viscoelastic behavior of the nanocomposites. The percolation volume fraction for the formation of GO network was found to be below 0.07%, while a corresponding GO aspect ratio of 400 was determined. The equilibrium shear modulus (vertical bar G(eq)*vertical bar) of the GO network and the critical strain gamma(c) of the nanocomposites could be described both by a power-law dependence on the volume fraction of GO nanoparticles. Further assessment of the structure formation of the GO nanoparticles was made in the solid state, wherein the shear modulus of GO was analyzed with the Halpin Tsai model. The values thus determined suggested the existence of tiled nanoplatelets within the formed network structure in the nanocomposites. The thermal properties of the nanocomposites were examined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The microstructure of the samples was also characterized using X-ray diffraction (XRD) measurements. (C) 2014 The Authors. Published by Elsevier Ltd.