Abstract
In this study, Fe(3)O(4)-chopped carbon fiber (CF) fillers with varying CF:Fe(3)O(4) weight ratios (1:0.5, 1:0.75, and 1:1) were fabricated using the wet chemical reduction method. Different weight percentages (1, 3, 7 wt.%) of the CF/Fe(3)O(4) fillers were used to fabricate lightweight, flexible, and porous thermoplastic polyurethane (p-TPU) composites for electromagnetic interference (EMI) shielding applications. Due to its poor electrical and magnetic properties, the TPU matrix alone exhibited negligible shielding effectiveness. The electromagnetic interference (EMI) performance of TPU composites is greatly affected by the amount of filler materials, the CF/Fe(3)O(4) ratio, and the porous structure, which in turn influence the interfacial interactions between filler and p-TPU matrix. Effective electromagnetic attenuation is achieved by conductive CF network, interfacial polarization at CF/Fe(3)O(4)/TPU interfaces, and multiple internal reflections promoted by microstructural heterogeneity and porosity. A maximum EMI shielding effectiveness (SE(T)) of 22.28 dB was achieved for a CF/Fe(3)O(4)/p-TPU composite with a filler load of 7 wt.%, a CF:Fe(3)O(4) ratio of 1:1, and a porosity of 15%.