Abstract In this study, we synthesized oriented multiwalled carbon nanotube (CNT)/polyethylene (PE) composite films and investigated their electromagnetic interference (EMI) shielding properties. The oriented CNT sheet structure was prepared by stacking CNT webs produced by a dry spinning technique with a CNT forest. In a near-field EMI attenuation measurement by a microstrip line method, composite films with a CNT fraction higher than 2 wt% showed a high attenuation that exceeded 50 dB at 10 GHz. This high attenuation was due to the enhanced magnetic anisotropy of the oriented CNTs and the encapsulated catalyst-derived cementite nanoparticles. This is the first report of high magnetic anisotropy in an oriented CNT structure for noise attenuation in a transmission line. In a far-field EMI shielding measurement by a coaxial tube method, the EMI shielding effectiveness (SE) significantly increased as the number of CNT web layers increased. A CNT/PE film with a high CNT fraction was found to have a high specific EMI SE of 0.6 dB/μm. The oriented CNT/PE composite film has great potential as a promising EMI material that demonstrates high shielding efficiency performance with low CNT loading.

中文翻译：

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单向取向薄多壁碳纳米管/聚乙烯薄膜优异的电磁干扰屏蔽特性

摘要 在本研究中，我们合成了定向多壁碳纳米管 (CNT)/聚乙烯 (PE) 复合薄膜，并研究了它们的电磁干扰 (EMI) 屏蔽性能。取向的 CNT 片结构是通过将干纺技术生产的 CNT 网与 CNT 林堆叠而制备的。在通过微带线方法进行的近场 EMI 衰减测量中，CNT 分数高于 2 wt% 的复合薄膜显示出在 10 GHz 下超过 50 dB 的高衰减。这种高衰减是由于定向碳纳米管和封装的催化剂衍生的渗碳纳米颗粒的磁各向异性增强。这是定向 CNT 结构中高磁各向异性的第一份报告，用于传输线中的噪声衰减。在通过同轴管法进行的远场 EMI 屏蔽测量中，随着 CNT 网层数量的增加，EMI 屏蔽效率 (SE) 显着增加。发现具有高 CNT 分数的 CNT/PE 膜具有 0.6 dB/μm 的高比 EMI SE。取向的 CNT/PE 复合膜作为一种有前途的 EMI 材料具有巨大的潜力，它在低 CNT 负载下表现出高屏蔽效率性能。