Excellent Electromagnetic Interference Shielding of Multi-layered Thermoplastic Poly- urethane Nanocomposites with CoFe 2 O 4 Nanoparticles and Graphite

Abstract This work presents multi-layered polymer-based nanocomposites that effectively block electromagnetic (EM) radiation by including magnetic and conductive fillers. The sonochemical method produced CoFe₂O₄ nanoparticles with a high degree of purity. The melt mixing process followed by compression moulding was utilized to generate individual layers of thermoplastic polyurethane (TPU) containing conductive graphite (G-TPU) or magnetic CoFe₂O₄ spinel ferrite nanoparticles (F-TPU) at a thickness of around 0.8 mm. Additionally, to create TPU-based multi-layered nanocomposites, three mono-layers of either F-TPU or G-TPU were stacked in an identical and alternating fashion. These were designated as F-TPU/F-TPU/F-TPU, G-TPU/G-TPU/G-TPU, F-TPU/G-TPU/F-TPU, and G-TPU/F-TPU/G-TPU which were further briefly represented as F/F/F, G/G/G, F/G/F, and G/F/G, respectively. The electromagnetic interference (EMI) total shielding effectiveness (SET) in the X-band frequency range of 8.2–12.4 GHz was investigated and observed to be 3.7 dB, 33.8 dB, 23.9 dB, and 54.0 dB for F/F/F, G/G/G, F/G/F, and G/F/G, respectively. This research offers a guide for engineers looking to create superior EMI shielding polymer nanocomposites, which have potential uses in radar security and information communications.