▎ 摘　　要

A detailed analysis of composites with epoxy matrix and three types of graphene-based nanofillers combining scanning transmission electron microscopy and electron energy loss spectroscopy was reported here. The composites were prepared by a three-roll milling method and the nanofillers were well dispersed in the matrix, as confirmed by SEM and scanning transmission electron microscopy observation. Mass density profiles through the interface from the matrix to the nanofillers were obtained thanks to the plasmon energy values measured from the low-loss spectra. The core-loss spectra revealed the chemical bonding states of different phase regions and identified the different chemical composition of graphite nanoplatelets (GNPs) in GNPs/epoxy and GNP-CNTs/epoxy composites. Energy dispersive spectroscopy mapping was also conducted to further confirm the components in different phase regions. The successful characterization of the chemical structure and the bonding states paves the way for a better understanding of the structure-property relationships in composites. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46748.