Research Center of Nano Science and Technology, College of Sciences, Shanghai University, Shanghai 200444, PR China.
Research Center of Nano Science and Technology, College of Sciences, Shanghai University, Shanghai 200444, PR China.
Int J Biol Macromol. 2024 Sep;276(Pt 1):133897. doi: 10.1016/j.ijbiomac.2024.133897. Epub 2024 Jul 15.
Liquid metal (LM) based electromagnetic interference (EMI) shielding materials with high conductivity and continuous deformation capacity are important needs for meeting modern advanced electronic equipment. However, an independent free-standing film with LM is difficult to achieve due to its unique fluidity properties. Here, a simple alternating filtration film-forming method was utilized to orderly construct a sandwiched EMI shielding film with LM stabilized by bio-based oxhide gelatin (gel) as the intermediate conductive layer, and two films of aramid nanofibers/oxhide gel (ANF/gel) as the external insulating protective layers. This design not only prevents LM from being exposed to environmental conditions, but also reduces the risk of chemical corrosion in practical applications. Under optimal LM addition conditions, the sandwiched film (0.3-3 L) exhibited better EMI shielding performance of 50.4 dB in the X-band than the blended film (0.7 dB), as well as excellent mechanical properties (tensile strength of 65.8 MPa, strain 8.6 %). More importantly, the sandwiched film still maintained reliable EMI shielding performance after being experienced largely physical deformation. This study provides a new solution for preparing LM-based EMI shielding composites, and is expected to arouse pursuit of high EMI shielding effects of bio-based gel while also paying attention to their safety.
基于液态金属（LM）的电磁干扰（EMI）屏蔽材料具有高导电性和连续变形能力，这是满足现代先进电子设备的重要需求。然而，由于其独特的流动性，独立的自支撑 LM 薄膜很难实现。在这里，采用了一种简单的交替过滤成膜方法，利用生物基牛皮胶（gel）作为中间导电层来有序构建夹芯 EMI 屏蔽膜，并用芳纶纳米纤维/牛皮胶（ANF/gel）作为外部绝缘保护层。这种设计不仅可以防止 LM 暴露在环境条件下，还可以降低实际应用中化学腐蚀的风险。在最佳的 LM 添加条件下，夹芯薄膜（0.3-3 L）在 X 波段表现出比共混薄膜（0.7 dB）更好的 EMI 屏蔽性能，达到 50.4 dB，同时还具有优异的机械性能（拉伸强度为 65.8 MPa，应变 8.6%）。更重要的是，夹芯薄膜在经历了大量的物理变形后仍能保持可靠的 EMI 屏蔽性能。本研究为制备基于 LM 的 EMI 屏蔽复合材料提供了一种新的解决方案，有望在追求生物基凝胶高 EMI 屏蔽效果的同时，也关注其安全性。
