Graphene-Based Thermoplastic Composites as Extremely Broadband and Frequency-Dependent EMI Absorbers for Multifunctional Applications

Abstract

Multifunctional materials are the future of modern electronics. The reduction of weight and no interfacial mismatches perfectly fit the requirements of those industry sectors which require miniaturization, low weight, and high functionality, like aerospace or wearable electronics. Here, we show multifunctional thermoplastic polymer composites based on acrylonitrile–butadiene–styrene (ABS) with graphene nanoplatelet (GNP) inclusions at different weight loadings of GNPs, from the pure polymer up to 10 wt %. The multifunctionality is expressed via efficient electromagnetic interference (EMI) shielding in an extensive frequency range, from microwave to terahertz, and good electrical conductivity and heat management. The highest measured total shielding efficiency reached over 80 dB per 1 mm-thick sample in the terahertz range for the 5 wt % GNP concentration. Composites with the highest GNP loading show high thermal conductivity of 1.8 W/mK and an electrical conductivity of 188 S/m. All composites exhibited absorption as the primary shielding mechanism. These are some of the highest EMI shielding efficiency and thermal conductivity values reported in the literature. Our results suggest that the ABS/GNP composites reported here are suitable for multifunctional EMI absorber/heat management applications.