Structures/Yarns/Fabrics for Biomedical Applications

摘要

Electrospinning, centrifugal spinning, and various other technologies can be utilized to produce nanofibers, which are usually collected as a web or mat. Because of the fineness of the fibers these mats can provide a very high fiber surface area with respect to the overall mat volume. This potentially offers advantages for use in filtration, tissue engineering, biomedical and various other technical applications. The use of nanofibers to create high surface area yarn structures has been the subject of much research but has achieved limited success on an industrial scale. Twisting of nanofiber often compacts the structure, which result in loss of porosity and available surface area.;The goal of the current research is to try to create yarn structures composed of nanofibers but which retain access to the large surface afforded by using the fine fibers. This work is based on a novel approach to try to create yarn like structures from nonwoven fabrics constructed from nanofibers, Different technologies, used for creating and consolidation yarn structures, are investigated and the most promising approaches are used to convert different widths of meltblown nonwoven fabric ribbon into yarns. Initial trials and observations helped in creating a novel way of twisting and drawing nonwoven ribbons into yarn structures and indicated the properties, which would be beneficial in the nonwoven fabric. In particular, it was clear that in order to provide the necessary geometry required access to the large surface area, the best approach would be to incorporate disparate fiber diameters. It was believed that this (i.e. a mixture of "coarser" and "finer" fibers) would prevent the fine fibers packing together and thus maintain potential access to the larger surface area. To this end co-form meltblown nonwoven technology was utilized to create a nonwoven fabric with a bimodal distribution of fiber diameters, which allowed in achieving bulky yarn structures while maintaining potential surface area for yarn structures.