Stretchable liquid metal grid/metallized polyurethane composites with switchable electromagnetic interference shielding and efficient infrared stealth performance

• Published in: Chemical engineering journal (Lausanne, Switzerland : 1996) Switzerland : 1996), 2024-11, Vol.500, p.157311, Article 157311
• Main Authors: Lu, Yezi, Tang, Xinwei, Li, Shuangshuang, Zhu, Mingyang, Hong, Wei, Chen, Haijun, Duan, Yiqian, Wang, Zixuan, Qiu, Hao, Li, Yan, Hu, Zaiyin, Wang, Wenjian, Wang, Zicheng, Liu, Tianxi
• Format: Article
• Language: English
• Subjects: Electromagnetic interference shielding; Liquid metal; Low-reflectivity; Nonwoven fabric; Polyurethane
• ISSN: 1385-8947
• DOI: 10.1016/j.cej.2024.157311

A switchable and low-reflectivity EMI shielding composite is fabricated by electroless nickel plating of polyurethane (Ni@TPU) and spraying liquid metal (LM) grid. The synergistic combination of Ni@TPU and LM grid facilitates the construction of hierarchical impedance matching, endowing it with an excellent low-reflectivity EMI shielding performance. The switchable EMI shielding performance can be realized by repeatedly stretching. Additionally, fluffy nonwoven fabric and low-emissivity LM grid bring infrared stealth performance. Such multi-functional composite can be employed in window of camouflage container. [Display omitted] •A switchable and low-reflectivity EMI shielding nonwoven fabric is fabricated.•Hierarchical impedance boosts entrance and dissipation of EMW with low reflectivity.•Switchable EMI shielding performance can be easily realized by repeatedly stretching.•Fluffy nonwoven fabric and low-emissivity grid bring infrared stealth performance.•Such multi-functional composite can be employed in window of camouflage container. Intelligent electromagnetic interference (EMI) shielding materials with tunable electromagnetic shielding properties becomes a significant and urgent concern for information society. Hence, a switchable and low-reflectivity EMI shielding composite is fabricated by electroless nickel plating on the surface of polyurethane nonwoven fabric (Ni@TPU), and followed by combining with liquid metal (LM) grid. The synergistic combination of Ni@TPU and LM grid effectively facilitates the rational construction of hierarchical impedance matching. Meanwhile, it promotes destructive interference between electromagnetic waves reflected from Ni@TPU and the LM grid. As a result, an excellent low-reflectivity EMI shielding performance can be achieved. More importantly, the switchable EMI shielding performance can be easily realized by repeatedly stretching Ni@TPU/LM. In addition, the fluffy nonwoven fabric and LM grid with low infrared emissivity endow it with an outstanding infrared stealth performance. Such excellent low-reflectivity EMI shielding switch performance incorporated with flexible infrared stealth makes it possible to become smart EMI shielding material with a great promise to be employed in the application scenario of window in camouflage container.