Zhou Lu-Yu, Ye Jiang-Hao, Fu Jian-Zhong, Gao Qing, He Yong
State Key Laboratory of Fluid Power and Mechatronic Systems, School of Mechanical Engineering, Zhejiang University, Hangzhou 310027, China.
Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province, School of Mechanical Engineering, Zhejiang University, Hangzhou 310027, China.
ACS Appl Mater Interfaces. 2020 Mar 11;12(10):12068-12074. doi: 10.1021/acsami.9b22433. Epub 2020 Feb 27.
Four-dimensional (4D) printing of swellable materials have been viewed as an ideal approach to build shape morphing architectures. However, there is less variety in high-performance swellable materials, limiting its development. To address this challenge, we proposed a new strategy for designing high-performance thermal-responsive swellable materials. The reversible liquid-vapor phase change of embedded low boiling point liquid chambers and functional liquid metal fillers endows the designed elastomer with the reversible thermal-responsive swellable property with high stability, fast response speed, and large equilibrium deformation. Notably, liquid metal fillers play a crucial role in improving the thermal-responsive property via improving the thermal conductivity and fracture toughness and decreasing the stiffness. To demonstrate the feasibility of constructing shape morphing architectures with proposed thermal-responsive liquid metal elastomers, typical bilayer structures were printed and investigated. By altering the key design parameters, the response speed and equilibrium deformation can be adjusted as needed. Therefore, complex shape morphing architectures can be printed. This study could provide a new avenue to design swellable material systems for 4D printing of shape morphing architectures.
可膨胀材料的四维（4D）打印被视为构建形状变形结构的理想方法。然而，高性能可膨胀材料的种类较少，限制了其发展。为应对这一挑战，我们提出了一种设计高性能热响应性可膨胀材料的新策略。嵌入式低沸点液体腔室和功能性液态金属填料的可逆液-气相变赋予了所设计的弹性体可逆的热响应性膨胀特性，具有高稳定性、快速响应速度和大的平衡变形。值得注意的是，液态金属填料通过提高热导率和断裂韧性以及降低刚度，在改善热响应性能方面起着关键作用。为了证明用所提出的热响应性液态金属弹性体构建形状变形结构的可行性，打印并研究了典型的双层结构。通过改变关键设计参数，可以根据需要调整响应速度和平衡变形。因此，可以打印出复杂的形状变形结构。这项研究可以为设计用于形状变形结构4D打印的可膨胀材料系统提供一条新途径。
