Fabrication of electrically conductive interconnected microcellular thermoplastic elastomeric foam composite for absorption dominating electromagnetic interference shielding with ultra low reflection

The elevated rates of electromagnetic radiation pollution, resulting from the growing need for wireless communication systems and electronic gadgets, have sparked interest in creating shielding materials that are lightweight, flexible, non-corrosive, simply processable, and affordable. In this study, a collection of microcellular nanocomposites based on ethylene octane copolymer (EOC) were created utilizing Vulcan XC 72 conductive carbon black (VCB) by a dual mixing process involving both melt and solution mixing. A chemical blowing agent was utilized to induce the cellular architecture in the composite, resulting in its lightweight nature (maximum density of 0.65 g/cc). The composite foam, when loaded with 30 parts per hundred of volume (phr) of VCB, displays a conductive network and also achieves an electromagnetic interference (EMI) shielding efficiency of 23.2 decibels (dB), satisfying commercial requirements. Furthermore, the findings indicated that the composite's cellular structure significantly influences the absorption-dominated EMI shielding mechanism with an absorption rate of 89%-94% and a specific shielding effectiveness of 194 dB[cm.sup.2]/g within the frequency range of 8.2-12.4 GHz (X band). The foam composite also demonstrated as a thermal management system, with a maximum thermal conductivity of 0.3 W/mK. As a result, this lightweight, easily processable, electrical conductive EOC/VCB polymer composite foams are projected to be used as EMI shielding materials in electronics, cars, and packaging. Highlights * Fabrication of lightweight microcellular Carbon black-loaded EOC composite * Rheological, mechanical, and thermal properties of foam composites * The cell density filled composites reduces by the cellular foam structures * Carbon black pronouncedly enhanced the electrical conductivity of foam composite * An absorption-dominated shielding effectiveness with ultra-low reflection. KEYWORDS conductive carbon black, electrical conductivity, EMI shielding, ethylene-octene copolymer, microcellular foam

1 | INTRODUCTION With 5G technology and the growing need for highspeed, compact, portable electronics, and communication devices, electromagnetic (EM) wave pollution has become a major issue. (1-3) Electronic devices [...]