Morphological and electrical characterization of epoxy resin filled with exfoliated graphite

An aeronautic epoxy resins with enhanced mechanical properties is morphologically and electrically characterized to study the effect of different percentages of exfoliated graphite (EG) inclusion. In particular, nanocomposites filled with graphite, characterized by 56% of the exfoliation degree and Brunauer-Emmett-Teller (BET) specific surface area of 14.7 m2/g were prepared with loading levels from 0.32% to 6.5% by weight (wt). The morphological characterizations show the peculiarities of the filler dispersion. The DC electrical characterization puts in evidence a percolation threshold (EPT) lower than 3% wt and an electrical conductivity of about 0.66 S/m in the case of samples filled at 6.5% wt. The AC electrical characterization in the frequency range 100Hz-1MHz of the nanocomposites is also reported in order to investigate the material properties around the EPT.