ANALYSIS OF THE SUPERDRAWING PROCESS OF HOLLOW FIBERS Investigators

In a superdrawing process, a polymer filament is elongated without developing much orientation and crystallization. Exploiting this phenomenon may bring about lower cost, more flexible and faster response in synthetic fiber production. This project seeks to understand the fundamental principles of superdrawing, and to study its application to hollow fiber production. Hollow fibers are high value added products used widely for household textiles such as insulation and filling materials. They are increasingly finding applications in emerging technical and biomedical textiles, and in chemical processing industry for gas separation. The fundamental understanding to be gained in this project can lead to a new approach in fiber manufacturing, enabling the US fiber and textile industry to improve the manufacturing processes for greater consistency, better product quality, improved processing efficiency, faster response to customer demand, and lower cost. We have conducted a series of experiments to determine the processing conditions for superdrawing, particularly the effect of temperature and drawing rate on the morphology of PET fibers. The theoretical model has been implemented to predict the final hollow fiber geometry (inner and outer diameters) after superdrawing in hot water. Superdrawing in steam has also been considered. Due to page limitation, this report focuses on the experimental studies of PET fiber structure-property as affected by the drawing conditions.