Self-shrinking soft demoulding for complex high-aspect-ratio microchannels

    Microchannels are the essential elements in animals, plants, and various artificial devices such as soft robotics, wearable sensors, and organs-on-a-chip. However, three-dimensional (3D) microchannels with complex geometry and a high aspect ratio remain challenging to generate by conventional methods such as soft lithography, template dissolution, and matrix swollen processes, although they are widespread in nature. Here, we propose a simple and solvent-free fabrication method capable of producing monolithic microchannels with complex 3D structures, long length, and small diameter. A soft template and a peeling-dominant template removal process are introduced to the demoulding process, which is referred to as soft demoulding here. In combination with thermal drawing technology, microchannels with a small diameter (10 ┬Ám), a high aspect ratio (6000, length-to-diameter), and intricate 3D geometries are generated. We demonstrate the vast applicability and significant impact of this technology in multiple scenarios, including soft robotics, wearable sensors, soft antennas, and artificial vessels.



Dongliang Fan, Xi Yuan, Wenyu Wu, Renjie Zhu, Xin Yang, Yuxuan Liao, Yunteng Ma, Chufan Xiao, Cheng Chen, Changyue Liu, Hongqiang Wang* , and Peiwu Qin*. Self-shrinking soft demoulding for complex high-aspect-ratio microchannels. Nature Communications , 2022, 13, 5083.