Abstract:

Through 3D printing technology, a microfluidic channel capable of spinning core-shell calcium alginate microfibers was quickly prepared, and precise control of the fiber morphology and structure was achieved. The effects of three phase flow rates, solution viscosity, channel height and undertake tube length on the morphology and structure of the prepared fibers were studied. The experimental results show that compared with other methods, the 3D printing method is more convenient and stable for the preparation of spinning channels, and the batch stability of the channels is high, so it is suitable for the mass production of microfibers. For the morphology control of the fibers, increasing the outer phase velocity can reduce the fiber diameter, increasing the middle phase velocity can increase the shell thickness, and increasing the inner phase velocity can increase the diameter of the nucleus. The change of solution viscosity has little effect on the fiber morphology. The greater the distance between the outlet of the microchannel and the solidification liquid, the thinner the fiber. If the length of the receiving tube is too short, the fiber will be uneven. The core-shell structure of fibers makes it easy to load functional substances and has potential application in the field of drug delivery.

Key words: microchannels, microfluidics, 3D printing, fiber, multiphase flow

摘要：

通过3D打印技术，快速制备了能够纺制核壳型海藻酸钙微纤维的微流控通道，并实现了对纤维形貌结构的精准调控。系统研究了三相流速、通道高度、承接管长度、溶液黏度对纤维形貌的影响。实验结果表明，增大外相流速可以减小纤维整体尺寸，增大中间相流速会增加壳层厚度，增大内相流速能增加核的直径；微通道出口距离固化液的高度越大，纤维越细；承接管长度过短会使纤维不均匀；溶液黏度对纤维的形貌影响很小。3D打印技术制备的微通道相比于其他制备方法更加便捷，易于加工，且通道的批次重复性良好，非常适合用于微纤维的批量生产。此外，纤维核壳型结构使其易于负载功能性物质，在载药释放领域具有潜在应用价值。

关键词: 微通道, 微流体学, 3D打印, 纤维, 多相流