3D printing technique for microfluidics provides a rapid and cost-effective manufacturing method in one step without considering the complex three-dimensional structures. Because of the layer-by-layer printing process, the microchannel was characterized with rough surface while lacking research on it. Currently, the surface roughness of microchannels is improved mainly by etching (solvent vapor or wet chemical etching), which has two disadvantages: material selectivity and channel openness. In this study, the Polydimethylsiloxane (PDMS) coating method was employed to improve the surface quality of 3D printed microchannels to address the problems mentioned above. The adhesion strength of PDMS on 3D printed substrate was tested. The method proposed in this paper not only reduced the surface roughness of the microchannel effectively (40 fold for circular microchannels) but also reduced the pressure drop of the PDMS coated microchannel by 63.7% and reduced the leakage rate of the 3D...

中文翻译：

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3D打印微通道的表面粗糙度改善

用于微流控技术的3D打印技术只需一步即可提供一种快速且经济高效的制造方法，而无需考虑复杂的三维结构。由于逐层印刷工艺，微通道的特征是表面粗糙，而对此却缺乏研究。当前，微通道的表面粗糙度主要通过蚀刻（溶剂蒸汽或湿化学蚀刻）来改善，这具有两个缺点：材料选择性和通道开放性。在这项研究中，采用聚二甲基硅氧烷（PDMS）涂覆方法来改善3D打印微通道的表面质量，以解决上述问题。测试了PDMS在3D打印基材上的粘合强度。