Towards a cost-effective carbon nanofillers-based composites for EMI shielding applications

Abstract

This work investigates the idea of using a mixture of nanofillers to reduce the cost of raw materials needed to achieve certain levels of electrical conductivity and electromagnetic interference (EMI) shielding. Composites based on polypropylene/polyethylene PP/PE as a polymer matrix and carbon nanotubes (CNT) or CNT: carbon black (CB) mixture as conductive nanofillers were prepared by melt mixing. Because CNT has higher electrical conductivity and aspect ratio than CB, CNT-based composites exhibited higher EMI shielding than CNT:CB-based composites. However, to formulate a composite with an EMI shielding of 30 dB, if the CNT/CB price ratio is higher than 2.0, the CNT:CB-based composite will have a cost advantage over the CNT-based composite. Even though the hybrid mixture did not show synergistic effects on the properties, it can help reduce the cost of the raw materials by replacing a portion of the expensive nanofiller.