Synergistic Effect of Graphite and Carbon Nanotubes on Improved Electromagnetic Interference Shielding Performance in Segregated Composites

Abstract

Herein, the graphite–carbon nanotube (G-CNT) hybrid loaded ultrahigh molecular weight polyethylene (UHMWPE) composite with a segregated structure was fabricated. In such structure, the G-CNT hybrid was selectively distributed at the interfaces of UHMWPE domains to form interconnected networks, as demonstrated by optical microscopy and scanning electron microscopy. The resultant G-CNT/UHMWPE composite exhibited an excellent electrical conductivity of 195.3 S m–1 and an ultrahigh electromagnetic interference shielding effectiveness (EMI SE) of 81.0 dB. The results were superior to those of single graphite or the CNT loaded one, clearly confirming the synergistic effect of graphite and CNT. Amazingly, only a specimen of 0.5 mm thickness imparted the G-CNT/UHMWPE composite with an EMI SE of 31.8 dB, already matching the requirement for commercial EMI shielding applications. This work highlights the merit of integrating the segregated structure with the synergistic effect of G-CNT hybrid in forming highly conductive networks and developing efficient EMI shielding materials.