Electromagnetic Wave Shielding Effectiveness Based on Carbon Microcoil-Polyurethane Composites

Carbon microcoils (CMCs) were deposited onto Al2O3 substrates using C2H2/H-2 as source gases and SF6 as an incorporated additive gas in a thermal chemical vapor deposition system. CMC-polyurethane (PU) composites were obtained by dispersing the CMCs in the PU with a dimethylformamide additive. The electromagnetic wave shielding properties of the CMC-PU composites were examined in the frequency range of 0.25-1.5GHz. The shielding effectiveness (SE) of the CMCs-PU systematically increases with increasing the content of CMCs and/or the layer thickness. Based on these results, the main SE mechanism for this work was suggested and discussed.