4D Printing of Hydrogels Controlled by Hinge Structure and Spatially Gradient Swelling for Soft Robots
4D Printing of Hydrogels Controlled by Hinge Structure and Spatially Gradient Swelling for Soft Robots
复制标题
DOI：
10.3390/machines11010103
复制
发表时间：
2023-01
期刊：
影响因子：
2.6
通讯作者：
Masanari Kameoka;Yosuke Watanabe;MD Nahin Islam Shiblee;M. Kawakami;J. Ogawa;A. Khosla;H. Furukawa;S. Zhang;S. Hirai;Zhongkui Wang
中科院分区：
文献类型：
--
作者：
Masanari Kameoka;Yosuke Watanabe;MD Nahin Islam Shiblee;M. Kawakami;J. Ogawa;A. Khosla;H. Furukawa;S. Zhang;S. Hirai;Zhongkui Wang
在4D打印中，具有物理性质梯度的结构被3D打印，以显着增加变形。例如，已经提出了打印具有被动层和主动层的双层结构，但这些方法存在每层材料混合，建模过程复杂的缺点。在此，我们提出了一种方法，通过简单地增加引发剂的量，使用单一材料在紫外线暴露的一侧和另一侧产生不同程度聚合的梯度凝胶。这种凝胶是第一个例子，其中两侧之间的不同膨胀比导致梯度向内卷曲向紫外线暴露的一侧。测试了不同材料浓度和不同结构下的力学性能（膨胀比和杨氏模量），并分析和模拟了各自对变形的影响。结果表明：引发剂浓度为0.2 （mol/L）以上会引起凝胶的变形，交联剂浓度增加3倍以上会引起凝胶的变形，铰链结构的加入使凝胶的变形范围限制在90°以内。因此，通过模拟可以在一定程度上预测最大变形。在未来，我们将能够创建复杂的结构，同时利用模拟。
In 4D printing, structures with gradients in physical properties are 3D printed in order to dramatically increase deformation. For example, printing bilayer structures with passive and active layers has been proposed, however, these methods have the disadvantages that the material of each layer is mixed, and the modeling process is complicated. Herein, we present a method of creating gradient gels with different degrees of polymerization on the UV-exposed side and the other side using a single material by simply increasing the amount of initiator. This gel is the first example in which the differential swelling ratio between two sides causes the gradient to curl inward toward the UV-exposed side. The mechanical properties (swelling ratio and Young’s modulus) were measured at different material concentrations and structures, and the effects of each on deformation were analyzed and simulated. The results show that adding an initiator concentration of 0.2 (mol/L) or more causes deformation, that increasing the crosslinker concentration by a factor of three or more increases deformation, and that adding a hinge structure limits the gradient gel to deformation up to 90°. Thus, it was found that the maximum deformation can be predicted to some extent by simulation. In the future, we will be able to create complex structures while utilizing simulation.