Investigation and comparison of electromagnetic properties of epoxy-graphene and epoxy-carbon nanotube nanocomposites

In this study, the effect of carbon nanotubes and single layers of graphite (graphene) on the electromagnetic properties of epoxy were investigated and compared. To do this, the epoxy-graphene nanocomposite and epoxy-carbon nanotube nanocomposite samples up to 0.5wt% were fabricated by casting method. After that, the morphology and distribution of nano-fillers in epoxy matrix was investigated by scanning electron microscopy. Then, the electromagnetic properties of samples in the X-band (8 to 12 GHz) of electromagnetic radiation were determined by a scalar network analyzer. The results showed that the electromagnetic properties and dissipation factor of epoxy were improved by graphene much more than of carbon nanotubes. So that, by adding of 0.5wt% of graphene or carbon nanotubes in epoxy matrix, the real part of permittivity was improved by 36 and 16 percent respectively. The average value of the imaginary part of permittivity of 0.5wt% of graphene nanocomposite sample was reached to 0.5 that is 3 and 12.5 times of 0.5wt% of carbon nanotubes nanocomposite sample and pure epoxy respectively. The 0.13 and 0.045 was obtained for dissipation factor of nanocomposite samples with 0.5wt% of graphene and 0.5wt% of carbon nanotube respectively. As the results, epoxy nanocomposites containing graphene are more suitable than epoxy-carbon nanotubes nanocomposites for electromagnetic interference shielding and absorbing electromagnetic waves absorption application.