▎ 摘　　要

A novel modifier, 1H, 1H, 2H, 2H-Perfluorooctyltriethoxysilane (PFOES), was introduced for the covalent functionalization of graphene for the first time. TEM, XPS, FT-IR, Raman, AFM and TGA were employed to characterize the morphology and structure of the PFOES-rGO. Furthermore, PVDF/PFOES-rGO composite films with different PFOES-rGO loadings were prepared by solution mixing. The dispersion of such PFOES-rGO containing fluorine ended-groups in PVDF was effectively improved compared to graphene as SEM showed. Thus, the PFOES-rGO could nucleate the PVDF crystallization and induce the formation of nearly all beta phase. The dielectric, piezoelectric and dynamic mechanical properties of the PVDF/PFOES-rGO composite films were then comprehensively studied. The dielectric (at 1 kHz) and the piezoelectric constants of the PVDF/PFOES-rGO composite film at 0.3 wt% PFOES-rGO compared with the neat PVDF was greatly improved by 370% and 80.9%, respectively. The PFOES-rGO also greatly enhanced the mechanical property of PVDF composites. It is proved the modification method for graphene used in this study is very effective. (C) 2016 Elsevier B.V. All rights reserved.