Skrivanek Josef, Holec Pavel, Batka Ondrej, Bilek Martin, Pokorny Pavel
Department of Textile Machine Design, Faculty of Mechanical Engineering, Technical University of Liberec, 461 17 Liberec, Czech Republic.
Department of Nonwovens and Nanofibrous Materials, Faculty of Textile Engineering, Technical University of Liberec, 461 17 Liberec, Czech Republic.
Polymers (Basel). 2022 Mar 5;14(5):1042. doi: 10.3390/polym14051042.
This paper addresses the changing of the process parameters of nozzleless centrifugal spinning (forcespinning). The primary aim of this study was to determine the dependence of the final product on the dosing of the polymer, the rotation speed of the spinneret and the airflow in order to determine the extent of the technological applicability of aqueous polyvinyl alcohol (PVA) and its modifications. PVA was chosen because it is a widely used polymeric solution with environmentally friendly properties and good biodegradability. It is used in the health care and food packaging sectors. The nanofibrous layers were produced by means of a mobile handheld spinning device of our own construction. This mobile application of the spinning machine has several limitations compared to stationary laboratory equipment, mainly due to dimensional limitations. The uniqueness of our device lies in the possibility of its actual use outside the laboratory. In addition to improved mobility, another exciting feature is the combination of nozzleless forcespinning and fiber application using airflow. Dosing, the rotation speed of the spinnerets and the targeted and controlled use of air comprise the fundamental technological parameters for many devices that operate on a centrifugal force system. The rotation rate of the spinnerets primarily affects the production of fibers and their quality, while the airflow acts as a fiber transport and drying medium. The quality of the fibers was evaluated following the preparation of a testing set for the fiber layers. The most suitable combinations of rotation speed and airflow were then used in subsequent experiments to determine the ideal settings for the device. The solution was then modified by reducing the concentration to 16% and adding a surfactant, thus leading to a reduction in the diameters of the resulting fibers. The nanofiber layers so produced were examined using a scanning electron microscope (SEM) in order to analyze the number of defects and to statistically evaluate the fiber diameters.
本文探讨了无喷嘴离心纺丝（强力纺丝）工艺参数的变化。本研究的主要目的是确定最终产品与聚合物剂量、喷丝头转速和气流之间的关系，以确定水性聚乙烯醇（PVA）及其改性材料的技术适用范围。选择PVA是因为它是一种广泛使用的聚合物溶液，具有环保特性和良好的生物降解性。它用于医疗保健和食品包装领域。纳米纤维层是通过我们自己制造的便携式手持纺丝装置生产的。与固定的实验室设备相比，这种纺丝机的便携式应用有几个局限性，主要是由于尺寸限制。我们设备的独特之处在于它可以在实验室外实际使用。除了提高移动性外，另一个令人兴奋的特点是无喷嘴强力纺丝与利用气流进行纤维应用的结合。剂量、喷丝头转速以及有针对性和可控地使用空气是许多基于离心力系统运行的设备的基本工艺参数。喷丝头的转速主要影响纤维的生产及其质量，而气流则作为纤维的输送和干燥介质。在制备纤维层测试装置后，对纤维质量进行了评估。然后在后续实验中使用最合适的转速和气流组合来确定设备的理想设置。然后通过将浓度降低到16%并添加表面活性剂对溶液进行改性，从而使所得纤维的直径减小。使用扫描电子显微镜（SEM）对如此生产的纳米纤维层进行检查，以分析缺陷数量并对纤维直径进行统计评估。
