**2.4 Graphene**

The study of graphene is one of the most interesting areas in condensed matter and materials science physics [22]. Moreover, graphene has the potential for many

## *Graphene Reinforced Polymer Matrix Nanocomposites: Fabrication Method… DOI: http://dx.doi.org/10.5772/intechopen.108125*

applications in several fields [23, 24]. The plurality of the original research into graphene has focused on its thermal and mechanical properties and analyzed its use in manufacturing applications [25, 26]. A hexagonal ring structure of graphene is formed by a single-atomic layer of sp<sup>2</sup> hybridized carbon atoms organized in hexagonal honeycomb structures that are chemically linked to three others with a carbon–carbon bond length of 0.142 nm. Graphite, a 3D layered crystal lattice structure, is formed by stacking parallel 2D graphene sheets. In graphite, weak van der Waals forces hold neighboring graphene sheets together, with a separation distance of 0.335 nm as shown in **Figure 2**. Graphene research has now extended significantly, amidst growing recognition that graphene could have exciting and interesting physical behavior and features such as high stiffness and strength, thermal and electrical conductivity and impermeability to gases (helium, oxygen, nitrogen, etc.). For applications in the nanocomposites field [28, 29], researchers looking at other nanocomposite forms have recently refocused their efforts on graphene nanocomposites. Furthermore, there was pre-existing expertise in graphite exfoliation and the preparation of graphene oxide from graphite oxide. Graphene oxide is related to reduced graphene oxide and pristine graphene by chemical modification [30].
