Investigation of electromagnatic shielding and flame retardancy properties of thermosetting based hybrid composites containting Fe3o4 and activated carbon obtained from solid waste

The demand for high-performance materials with flame-retardant and electromagnetic shielding properties has increased research efforts on sustainable and multifunctional composites. In this study, thermoset-based hybrid composites containing activated carbon derived from solid waste and Fe₃O₄ particles were investigated in terms of their flame-retardant and electromagnetic shielding properties. The activated carbon obtained by pyrolysis of solid waste exhibited a BET surface area of 714.33 m²/g and an electrical conductivity of 69.5 S/m, serving as a filler material that enhanced thermal stability and electrical performance. Fe₃O₄ particles contributed to electromagnetic absorption and shielding effectiveness. The structural and thermal properties of the prepared hybrid composites were characterized using thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and X-ray diffraction (XRD). Flame-retardant performance was evaluated by limiting oxygen index (LOI) and cone calorimeter tests. The highest LOI value of 41.1% was achieved in the Nov-5-45 sample. Electromagnetic shielding effectiveness (EMI SE) was measured over a wide frequency range, and the highest EMI SE performance was obtained in the Nov-5-45 sample containing 5 wt% activated carbon and 45 wt% Fe₃O₄. The synergy between activated carbon and Fe₃O₄ significantly improved both fire resistance and EMI shielding performance. With these properties, the developed composites can be considered potential candidates for advanced applications in electronics, aerospace, and defense industries. This study highlights the potential of waste-derived carbon materials in sustainable composite production and contributes to environmental sustainability by enabling the development of multifunctional, high performance materials.