Epoxy vitrimer based nanocomposites for EMI shielding: Integrating reprocessability, self-healing, and machine learning predictions

• Epoxy vitrimer composite with MWCNTs and CoFe 2 O 4 developed for EMI shielding • Disulfide bond of vitrimer demonstrated self-healing and reprocessability • Epoxy vitrimer showed electrical percolation threshold at 0.2 wt% MWCNTs • Optimal EMI shielding of −18.4 dB with 15 wt% CoFe 2 O 4 and 0.2 wt% MWCNTs • Machine and deep learning models predict EMI shielding and mechanical Properties The rapid evolution of electronic technologies necessitates multifunctional polymeric materials capable of offering robust electromagnetic interference (EMI) shielding, with mechanical durability, reprocessability and self-healing. The investigation utilized, epoxy vitrimer nanocomposites reinforced with conductive multi-walled carbon nanotubes (MWCNTs) and magnetic cobalt ferrite (CoFe) nanoparticles to engineer high-performance, reprocessable EMI shielding materials. The vitrimer matrix, synthesized using diglycidyl ether of bisphenol A (DGEBA) and 4-aminophenyl disulfide (4-AFD), was optimized to incorporate dynamic covalent disulfide bonds enabling thermal reprocessability, self-healing, and solvent resistance. A fixed MWCNTs content of 0.2 wt% established as the electrical percolation threshold was used to ensure a conductive network, while CoFe content was systematically varied from 0 to 20 wt%. The synergistic interplay between the conductive and magnetic fillers resulted in an optimal shielding effectiveness (SE T ) of -18.4 dB at 0.2 wt% MWCNTs and 15 wt% CoFe, primarily governed by absorption losses due to interfacial polarisation and multiple scattering. Mechanical and thermal analyses demonstrated a balanced trade-off between stiffness and toughness, with enhanced thermal stability, and reprocessability. Furthermore, machine learning (Random Forest) and deep learning (DNN with Adam optimiser) models were deployed to accurately predict the tensile properties and shielding effectiveness, offering a data-driven framework for design optimisation. The developed vitrimer composites also exhibited excellent solvent resistance and self-healing capability, underscoring their potential for sustainable, high-performance EMI shielding applications in aerospace, electronics, and defence industries.