Melt-Processed Graphite-Polypropylene Composites for EMI Shielding Applications

This study focuses on the mechanical, thermal properties, fracture morphology, and DC conductivity of graphite-reinforced polypropylene (PGP) composites for electromagnetic interference (EMI) shielding applications. Polypropylene (PP) and graphite powder (GP) are used as a matrix and filler materials to prepare PGP composites using a melt compounding technique. The results of thermal studies show that GP increases the thermal stability of PGP composites with an increase in filler amount. The tensile strength of the PGP composites was improved with the increase in GP content. The fracture morphology of the composites shows the clearance of polymer flow and good adhesion compatibility between PP and GP. Direct-current conductivity measurements indicate that PGP composites show an improvement in electrical conductivity. The EMI shielding effectiveness for PGP composites is -10.30 dB at 20 wt.% GP load in a bandwidth of X-band (8.2 GHz-12.4 GHz).