Graphite and Graphene Nanoplatelets (GNP) Filled Polymer Matrix Nanocomposites

Graphene is the basic constituent of graphite, carbon nanotubes and fullerenes. Graphene can present some structural defects, although its low dimensionality reduces the number of possible imperfections. Wallace showed the particular electronic structure of graphene. Thus, graphene is considered as a zero-gap semiconductor. In graphite, the cohesion of the crystal along the axis c⃗ is ensured by Van der Waals bonds. The basic principle of exfoliation techniques is to break these bonds, by the so-called dry method or in liquid phase, in order to obtain graphene. Due to its lamellar structure, graphite can accommodate chemical species, called inserts, in its interplanar spaces to give graphite intercalation compounds. The method of dispersion of nanofillers within a polymer matrix is as impactful on the final properties of the composite as the choice of the filler and its potential chemical treatment: it can strongly modify the different percolation thresholds.