空气隙纺丝过程中的单丝破裂

Filament breaches during air-gap spinning

如果聚合物在熔点范围以下分解,就采用溶液纺丝法。与熔体纺丝法大不相同,溶剂如二甲基甲酰胺(DMF)导致成本升高。主要因素是采购、维护、处置和员工防护。空气隙纺丝法属于溶液纺丝法,能提高生产速度,部分弥补了上述缺点,空气隙提供许多优点,能改变工艺气体,可能的不同液流形成多种多样的工艺。由于干法和湿法纺丝的结合,存在由两种工艺引起的单丝破裂,这种结合使整个工艺的稳定性差。目前亚琛工业大学纺织研究所(ITA)正集中研究这种工艺的纺丝试验。基于不同的机理,确定单丝破裂的典型特征是可能的。主要由文献中已知的机理描述了这类破裂,确定了有助于避免这些破裂的对策。

Solution spinning processes are used if polymers decompose below their melting range. In contrast to the melt spinning process, solvents like dimethylformamide （DMF） lead to rising costs. Main factors are purchase, handling, disposal and greater efforts for employee protection. The air-gap spinning method belongs to the solution spinning processes are allows a higher speed of production, which partly compensates for the disadvantages named before. The air-gap offers a lot of advantages. Process gases can be changed, and the different possible fluid flows lead to a high variability of the process. Due to the combination of dry- and wet-spinning, there are filament breaches caused by both processes. The combination leads to a low stability of the entire process. Current research at Institut fur Textilechnik RWTH Aachen University （ITA） concentrates on spinning experiments for this process. It was possible to identify typical characteristics of filament breaches, which are based on different mechanisms. These kinds of breaches are described by mechanisms mostly known from the literature. Strategies are identified which help to avoid those breaches.