Tang Jingda, Tong Zongfei, Xia Yukun, Liu Ming, Lv Zengyao, Gao Yang, Lu Tongqing, Xie Shejuan, Pei Yongmao, Fang Daining, Wang T J
State Key Lab for Strength and Vibration of Mechanical Structures, Department of Engineering Mechanics, Xi'an Jiaotong University, Xi'an, 710049, China.
J Mater Chem B. 2018 May 14;6(18):2713-2722. doi: 10.1039/c8tb00568k. Epub 2018 Apr 20.
Despite their potential in various fields such as soft robots, drug delivery and biomedical engineering, magnetic hydrogels have always been limited by their poor mechanical properties. Here a universal soaking strategy has been presented to synthesize tough magnetic nanocomposite (NC) hydrogels. We can simultaneously solve two common issues for magnetic hydrogels: the poor mechanical properties and poor distribution of magnetic particles. The toughness of the magnetic NC hydrogel achieves approximately 11 000 J m. The outstanding properties of tough magnetic hydrogels will enable myriad applications. Here we demonstrate a new application for remotely triggered shape morphing. Heterogeneous structures based on magnetic hydrogels are shown to evolve into bio-inspired three-dimensional (3D) shapes (lotus flowers) from 2D-structured sheets. The self-folding of the structure is controlled by the magnetothermal effect in an alternating magnetic field. The capability to control the shape morphing of a multi-material system by a magnetic field may emerge as a new general strategy for programming complex soft structures.
尽管磁性水凝胶在软机器人、药物递送和生物医学工程等各个领域具有潜力，但它们一直受到机械性能差的限制。本文提出了一种通用的浸泡策略来合成坚韧的磁性纳米复合（NC）水凝胶。我们可以同时解决磁性水凝胶的两个常见问题：机械性能差和磁性颗粒分布不均。磁性NC水凝胶的韧性达到约11000 J/m。坚韧磁性水凝胶的优异性能将使其有无数应用。在此，我们展示了一种远程触发形状变形的新应用。基于磁性水凝胶的异质结构被证明可以从二维结构薄片演变成受生物启发的三维（3D）形状（莲花）。结构的自折叠由交变磁场中的磁热效应控制。通过磁场控制多材料系统形状变形的能力可能会成为一种用于编程复杂软结构的新通用策略。
