EMI Shielding Characteristics of Expanded Graphite/Novolac Phenolic Resin Composite for Applications in Wireless Communication

Expanded graphite (EG) flakes are synthesized from natural graphite flakes of size ~2 μm employing chemical oxidation and thermal treatment method. The surface morphology and structural characterization of EG flakes are investigated using scanning electron microscope and X-ray diffraction respectively. EG flakes are mechanically mixed with novolac phenolic resin (NPR) in different weight ratios (30 wt%, 40 wt % & 50 wt %) and compressed with thermal treatment to develop expanded graphite/novolac phenolic resin(EG/NPR) composites. Shielding effectiveness (SE) of developed composites measured in the frequency range of 8 to 12 GHz shows a maximum values of -48 dB for 50 wt% EG/NPR composites.