Lee Ju-Yong, Oh Min-Ha, Park Joo-Hyeon, Kang Se-Hun, Kang Seung-Kyun
Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea.
Research Institute of Advanced Materials (RIAM), Seoul National University, Seoul 08826, Republic of Korea.
Polymers (Basel). 2023 Apr 23;15(9):2003. doi: 10.3390/polym15092003.
Three-dimensional (3D) printing has various applications in many fields, such as soft electronics, robotic systems, biomedical implants, and the recycling of thermoplastic composite materials. Three-dimensional printing, which was only previously available for prototyping, is currently evolving into a technology that can be utilized by integrating various materials into customized structures in a single step. Owing to the aforementioned advantages, multi-functional 3D objects or multi-material-designed 3D patterns can be fabricated. In this study, we designed and fabricated 3D-printed expandable structural electronics in a substrateless auxetic pattern that can be adapted to multi-dimensional deformation. The printability and electrical conductivity of a stretchable conductor (Ag-RTV composite) were optimized by incorporating a lubricant. The Ag-RTV and RTV were printed in the form of conducting voxels and frame voxels through multi-nozzle printing and were arranged in a negative Poisson's ratio pattern with a missing rib structure, to realize an expandable passive component. In addition, the expandable structural electronics were embedded in a soft actuator via one-step printing, confirming the possibility of fabricating stable interconnections in expanding deformation via a missing rib pattern.
三维（3D）打印在许多领域有各种应用，如柔性电子、机器人系统、生物医学植入物以及热塑性复合材料的回收利用。三维打印以前仅用于原型制作，目前正发展成为一种能够通过一步将各种材料集成到定制结构中加以利用的技术。由于上述优点，可以制造出多功能3D物体或多材料设计的3D图案。在本研究中，我们设计并制造了一种无基底负泊松比图案的3D打印可扩展结构电子产品，该产品可适应多维变形。通过加入润滑剂优化了可拉伸导体（Ag-RTV复合材料）的可打印性和导电性。Ag-RTV和RTV通过多喷嘴打印以导电体素和框架体素的形式打印，并以带有缺失肋结构的负泊松比图案排列，以实现一个可扩展的无源元件。此外，可扩展结构电子产品通过一步打印嵌入到一个软致动器中，证实了通过缺失肋图案在扩展变形中制造稳定互连的可能性。
