Yang Shengdu, Yang Pengcheng, Ren Chuanzheng, Zhao Xiaohai, Zhang Junhua
State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu 610065, China.
State Key Laboratory of Polymer Materials Engineering, Polymer Research Institute of Sichuan University, Chengdu 610065, China.
J Colloid Interface Sci. 2022 Sep 15;622:97-108. doi: 10.1016/j.jcis.2022.04.096. Epub 2022 Apr 25.
High-performance conductive polymer nanocomposites containing two-dimensional (2D) MXene are garnering substantial interest for electromagnetic shielding interference (EMI) in flexible electronics. However, owing to the non-sticky nature and undesirable mechanical performances of freestanding MXene film, it remains a formidable challenge to make the trade-off between outstanding EMI shielding capability and high stability. In this study, inspired by the structure and manufacturing process of millefeuille cakes, we propose a controllably layer-by-layer assembling strategy for fabricating flexible multilayered EMI shielding composite films based on MXene and an inherently conductive polymer (ICP). The multilayer films bearing alternating aramid nanofibers/polypyrrole nanowires (AFPy) and TiCT reinforced by waterborne polyurethane (TiCT@WPU) layers are orderly constructed by a facile alternating vacuum filtration method. Benefiting from the special architectures, the AFPy-70/TiCT@WPU-4 film exhibits a high electrical conductivity of 1.74 S cm and superior EMI shielding effectiveness of 40.9 dB at lower TiCT loading content (32 wt%). Moreover, synergistic integration of hydrogen bonding and π-π stacks in multilayered films is achieved, especially in tandem with controlled crack generation within the whole film. Excellent EMI shielding performance remains well maintained even after being suffered to back-and-forth bending test (over 10,000 cycles), ultrasonication, and cryogenic temperature, validating great potential as high-performance EMI shielding film resisting extreme conditions.
含有二维（2D）MXene的高性能导电聚合物纳米复合材料在柔性电子领域的电磁屏蔽干扰（EMI）方面引起了广泛关注。然而，由于独立的MXene薄膜具有不粘性和不理想的机械性能，在出色的EMI屏蔽能力和高稳定性之间进行权衡仍然是一项艰巨的挑战。在本研究中，受千层蛋糕的结构和制造工艺启发，我们提出了一种可控的逐层组装策略，用于制备基于MXene和本征导电聚合物（ICP）的柔性多层EMI屏蔽复合薄膜。通过简便的交替真空过滤方法，有序构建了带有交替的芳纶纳米纤维/聚吡咯纳米线（AFPy）和由水性聚氨酯增强的TiCT（TiCT@WPU）层的多层薄膜。得益于特殊的结构，AFPy-70/TiCT@WPU-4薄膜在较低的TiCT负载量（32 wt%）下表现出1.74 S cm的高电导率和40.9 dB的优异EMI屏蔽效能。此外，多层薄膜中实现了氢键和π-π堆积的协同整合，特别是在整个薄膜内可控裂纹产生的情况下。即使经过反复弯曲测试（超过10,000次循环）、超声处理和低温处理后，仍能保持出色的EMI屏蔽性能，验证了其作为高性能EMI屏蔽薄膜抵抗极端条件的巨大潜力。
