Abstract Ultrathin, flexible and anisotropic polyvinyl butyral (PVB)/graphite coated with nickel (Ni-Gr)/short-cut carbon fibre (SCF) cast films were fabricated using a convenient solution casting method. The effects of the filler components, contents, and their distribution structures on the electromagnetic shielding effectiveness (SE) of the composites are investigated. The results indicate that the hybridisation and distribution of fillers with different shapes could significantly improve the electromagnetic shielding performance. The anisotropic SE of the composites is due to the orientation of the SCFs in the casting direction, which was induced by the traction from the carrier tape of the casting machine. Moreover, the measured electromagnetic SE in the perpendicular direction was higher than that in the casting direction. The experimental results showed that the prepared composite films had excellent anisotropic SE in the measured frequency range of X band. The SE and specific SE of the PVB/Ni-Gr/SCF cast film with a mass ratio of 69/26/5 are 32 dB and 159 dB/mm, and 20 dB and 101 dB/mm, across and along the casting direction, respectively. The SE difference between the two directions of the microwave shielding material provides the potential to prepare a direction selective composite with an ultrahigh electromagnetic shielding performance. Moreover, the prepared composites showed great potential as microwave shielding materials in military and civilian applications.

中文翻译：

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具有高电磁屏蔽性能的超薄各向异性聚乙烯醇缩丁醛/镍石墨/短切碳纤维薄膜

摘要 使用方便的溶液浇铸方法制备了超薄、柔性和各向异性的聚乙烯醇缩丁醛 (PVB)/石墨镀镍 (Ni-Gr)/短切碳纤维 (SCF) 流延膜。研究了填料组分、含量及其分布结构对复合材料电磁屏蔽效率 (SE) 的影响。结果表明，不同形状的填料的混合和分布可以显着提高电磁屏蔽性能。复合材料的各向异性 SE 是由于 SCF 在铸造方向上的取向，这是由铸造机载带的牵引力引起的。此外，在垂直方向上测得的电磁 SE 高于在铸造方向上的电磁 SE。实验结果表明，所制备的复合薄膜在X波段的测量频率范围内具有优异的各向异性SE。质量比为 69/26/5 的 PVB/Ni-Gr/SCF 流延膜的 SE 和比 SE 分别为 32 dB 和 159 dB/mm，以及 20 dB 和 101 dB/mm，横跨和沿流延方向， 分别。微波屏蔽材料两个方向之间的SE差异提供了制备具有超高电磁屏蔽性能的方向选择性复合材料的潜力。此外，所制备的复合材料在军事和民用领域作为微波屏蔽材料显示出巨大的潜力。质量比为 69/26/5 的 PVB/Ni-Gr/SCF 流延膜的 SE 和比 SE 分别为 32 dB 和 159 dB/mm，以及 20 dB 和 101 dB/mm，横跨和沿流延方向， 分别。微波屏蔽材料两个方向之间的SE差异提供了制备具有超高电磁屏蔽性能的方向选择性复合材料的潜力。此外，所制备的复合材料在军事和民用领域作为微波屏蔽材料显示出巨大的潜力。质量比为 69/26/5 的 PVB/Ni-Gr/SCF 流延膜的 SE 和比 SE 分别为 32 dB 和 159 dB/mm，以及 20 dB 和 101 dB/mm，横跨和沿流延方向， 分别。微波屏蔽材料两个方向的 SE 差异为制备具有超高电磁屏蔽性能的方向选择性复合材料提供了可能。此外，所制备的复合材料在军事和民用领域作为微波屏蔽材料显示出巨大的潜力。