3D Highly Stretchable Liquid Metal/Elastomer Composites with Strain‐Enhanced Conductivity
3D Highly Stretchable Liquid Metal/Elastomer Composites with Strain‐Enhanced Conductivity
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DOI：
10.1002/adfm.202310225
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发表时间：
2023-10
影响因子：
19
通讯作者：
Ruyue Fang;Bin Yao;Tianwu Chen;Xinwei Xu;Dingchuan Xue;Wei Hong;Hong Wang;Qing Wang;Sulin Zhang
中科院分区：
文献类型：
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作者：
Ruyue Fang;Bin Yao;Tianwu Chen;Xinwei Xu;Dingchuan Xue;Wei Hong;Hong Wang;Qing Wang;Sulin Zhang
目前的可拉伸导体通常由注入刚性导电填料的弹性复合材料组成，可伸长性和耐久性有限，并且随着拉伸而电导率下降。这些限制阻碍了它们作为基本部件的潜在应用，如互连、传感器和可伸缩电子设备和软机器中的致动器。在此背景下，介绍了一种创新的弹性复合材料，它结合了液态金属(LM)的3D网络，提供了出色的延伸性、耐用性和导电性。力学模型阐明了互连的3DLM结构如何赋予复合材料柔软性和延伸性，使其能够承受高达500%的拉伸应变而不会断裂。3DLM网络相对较低的表面体积比限制了在循环拉伸过程中氧化层的重塑，从而有助于降低永久应变并提高耐久性。此外，3D架构便于裂纹钝化和应力离域，提高了抗裂性，同时建立了导致高导电性的连续导电路径。值得注意的是，在大幅拉伸过程中，3DLM复合材料的电导率随着应变的增加而增加，这突出了其应变增强的导电性。与其他具有0D Lm液滴的Lm基复合材料相比，3DLm复合材料以优异的性能脱颖而出。
Current stretchable conductors, often composed of elastomeric composites infused with rigid conductive fillers, suffer from limited stretchability and durability, and declined conductivity with stretching. These limitations hinder their potential applications as essential components such as interconnects, sensors, and actuators in stretchable electronics and soft machines. In this context, an innovative elastomeric composite that incorporates a 3D network of liquid metal (LM), offering exceptional stretchability, durability, and conductivity, is introduced. The mechanics model elucidates how the interconnected 3DLM architecture imparts softness and stretchability to the composites, allowing them to withstand tensile strains of up to 500% without rupture. The relatively low surface‐to‐volume ratio of the 3DLM network limits the reforming of the oxide layer during cyclic stretch, thereby contributing to low permanent strain and enhanced durability. Additionally, the 3D architecture facilitates crack blunting and stress delocalization, elevating fracture resistance, while simultaneously establishing continuous conductive pathways that result in high conductivity. Notably, the conductivity of the 3DLM composite increases with strain during substantial stretching, highlighting its strain‐enhanced conductivity. In comparison to other LM‐based composites featuring 0D LM droplets, the 3DLM composite stands out with superior properties.