Magnetic Field-Induced Alignment of Graphene Nanoplatelets in Carbon Fiber-Silicone Rubber Composites for Superior EMI Shielding and Thermal Conductivity

In this present study, graphene nanoplates (GNP) are aligned under the magnetic field in short carbon fiber (SCF)-polydimethylsiloxane (PDMS) composite, to understand the variation in electromagnetic interference (EMI) shielding effectiveness (SE), in X-band frequency. Initially, the GNP is aligned under the static magnetic field and with a rotating magnetic field (RMF) at lateral directions to form GNP-PDMS composites. X-ray diffraction (XRD) results indicate that the laterally applied RMF 5 wt% of GNP has a better alignment. Therefore, considering 5 wt% GNP as an optimum filler, SCF-GNP-PDMS hybrid composites are fabricated. Structural and morphological studies are carried out using XRD and HRSEM. The EMI shielding studies indicate that the laterally aligned GNP results in enhanced EMI SE of around 65.6 dB compared to the non-aligned sample giving around 58.1 dB. To understand the thermal properties, the laser flash analysis (LFA) was carried out. The thermography, thermal conductivity, and diffusion results indicate that laterally aligned samples have better heat transfer properties.