Processing and Properties of Graphene-Based Nanocomposites

Fabrication of carbon nanotubes is expensive, particularly for the purifying process required to make them widely accepted for reinforcements and structural composite applications. Instead of trying to discover lower cost processes for nanotubes, we seek to develop an alternative nanoscale carbon material with comparable properties that can be produced cost-effectively and in larger quantities. These carbon nanomaterials are referred to as nanoscale graphene platelets (NGP). In this study, we fabricated and studied graphene-based nanocomposites by (1) exfoliating carbon or graphite materials using acid treatment, thermal and microwave expansion, and (2) examined the electrical and dielectric properties of the graphite reinforced polymers. Less than 1 wt% filler content was required to reach the percolation threshold (φ_c) of transition in electrical conductivity and dielectric properties. Molecular dynamics simulation was employed to characterize the increase in elastic moduli for graphene platelets embedded in polymer matrices at molecular scale.