Influence of exfoliated graphite filler size on the electrical, thermal, and mechanical polymer properties

Exfoliated graphite has attracted significant research interest, especially with respect to composite manufacturing as a sheet shape material for enhancing their mechanical, electrical, and thermal properties with cost-effectiveness. It has been proved in different researches that size of nanoparticles plays a vital role and has significant effect. So, in this study, exfoliated graphite with three different sizes i.e. 50 mesh (large dimension), 100 mesh (medium size), and 150 mesh (small size) are integrated in epoxy to examine their effect on the mechanical/electrical/thermal performance of the material and for each mesh size range of 0.5 wt.% to 20 wt.% is utilized. These three systems of reinforced epoxy with different size of exfoliated graphite are evaluated in DIGIMAT simulation software by investigating their electrical, thermal and mechanical properties. The numerical results showed that integration of exfoliated graphite in neat epoxy drastically improved its electrical, thermal, and mechanical performance. In addition, it was found that the use of the bigger size was more effective on the performance of the material, which is probably because of the enhanced connectivity between the structuring sheets. Moreover, a gradual increase in properties is observed with increasing the percentage of exfoliated graphite content in each system. This numerical study was developed in accordance to validate the experimental study conducted by Debelak et al. This study further provides the evidence of the appropriateness of the DIGIMAT simulation as an investigational load in relevant research.