Promising Electromagnetic Interference Shielding Materials: Hybrid Fillers Reinforced Bio-Based Composites

Abstract

Electromagnetic pollution, also known as electromagnetic interference (EMI) issues, is a growing concern as electronic and telecommunication technologies advance. The resulting urgent demand for EMI shielding materials underscores the need for the development of high-performance, environmentally friendly shielding materials. Here, we assess the impact of multiscale carbon-based hybrid filler on the EMI shielding performance of polyamide 11/poly(lactic acid) composites. The effects of the amounts (0.5 to 5 wt%) of graphene nanoplatelets (GNPs) and multiwalled carbon nanotube (MWCNT) nanofillers in carbon fiber (CF)/GNP and CF/MWCNT-reinforced hybrid composites were comparatively investigated. The composites were fabricated through melt blending/compression molding and subsequently characterized in terms of morphological, fiber length, electrical properties, and EMI shielding effectiveness (EMI SE). Morphological imaging revealed a good adhesion between the fillers and the matrix, indicating a favorable interaction. The fiber length analysis demonstrated that fiber lengths were longer in CF/GNP hybrid composites than in CF/MWCNT. The EMI SE measurements showed the synergistic effects of the fillers in the X and Ku bands. The highest EMI SE values at 10 GHz and 16 GHz for the 20CF-5GNP composite were 34 and 40 dB, respectively.