Electromagnetic interference shielding behavior of flexible PVA composite made using betel nut husk biocarbon and steel microwire in E, F, I, and J band spectrum

Abstract This study investigates the electromagnetic interference (EMI) shielding behavior of a flexible polyvinyl alcohol (PVA) composite fabricated using betel nut husk biocarbon and steel microwire in the E, F, I, and J band spectrum. The incorporation of steel microwire into the PVA based composite is novel approach since it provides flexibility along with good mechanical strength. The fabrication process involves the solution casting method, and the composite is characterized according to American society of testing and materials (ASTM) standards. The research focuses on analyzing dielectric behavior, EMI shielding effectiveness, and mechanical properties. Results indicates that, the composite with 5 vol.% of biocarbon and 5 vol.% of micro metal wire, exhibits exceptional relative permittivity of 7.6, 6.9, 6.3, and 1.5 for E, F, I, and J frequency bands and same composition delivers exceptional electromagnetic shielding with total shielding values of 17.7 dB, 25.5 dB, 31.7 dB, and 38.6 dB for E, F, I, and J frequency bands. In mechanical characteristics, composite with 5 vol.% of biocarbon and 5 vol.% of micro metal wire, exhibits high tensile strength of 73 MPa with lower elongation percentage of 109.2% and shore‐D hardness of 40, respectively. Thus, the inclusion of betel nut husk biocarbon and steel microwire into the PVA matrix enhanced the overall EMI shielding properties along with mechanical properties. These flexible EMI shielding composites could be used in applications such as defense, telecommunication, drones, and electronic gadget making segments. Highlights Flexible polyvinyl alcohol (PVA) composite is made with steel microwire and betel nut husk biocarbon. Biocarbon is derived from betel nut husk for first time and used as EM wave absorber. Composites were made via simple solution casting method for high flexibility index. Composite contains 5 vol.% biocarbon and 5 vol.% micro metal wire, shows high relative permittivity 7.6 for E frequency bands. The composites have high tensile strength of 73 MPa with a low elongation percentage of 109.2% and a shore‐D hardness of 40.