Electromagnetic Wave Shielding Effectiveness Based on Carbon Microcoil‐Polyurethane Composites

Carbon microcoils (CMCs) were deposited onto Al 2 O 3 substrates using C 2 H 2 /H 2 as source gases and SF 6 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 0.25–1.5 GHz. 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.