In this issue: Research Articles Newly Elected JTATM International Editorial Board Academia Tours US Textile Plants: A Graduate Perspective Abstracts for the Spring 2001 Fiber Society Conference

Mission Statement To establish a high quality forum relevant to the needs of global industry and higher education that will provide leadership in the timely dissemination of information dealing with all aspects of textile and apparel, technology and management.

Trevor Little and Behnam Pourdeyhimi
North Carolina State University

The textile complex has for many years sought to duplicate the properties of natural fibers such as silk, wool and cotton by producing manmade synthetic fibers in similar diameters or slightly finer. The results have been very successful and over the past 50 years, an entire range of new polymeric fibers has emerged. There is still much debate as to whether the properties and functionality of the natural fibers have been duplicated and continuing research has improved both the natural fiber as well as its manmade counterpart. As we look to the future requirements for the textile complex, there is a significant trend towards multi-functional textiles.

Multi-functional textile materials represent a classification for textile and clothing systems that have inherent multi-functionality. For example, a multi-functional scenario might be fire resistant, lightweight, comfortable and waterproof for a clothing system. The challenge for the Textile Materials Technologist is to develop the critical elements or components to be able to combine multiple functions into a single textile system. In essence, the more useful functions that can be combined, the more value is added for the customer.

The academic search for components that will permit the design of multi-functional textile structures has led us to extend the range of fiber diameters and cross-sections that can be produced. It is reasonably safe to state that today fibers can be engineered from traditional diameters all to way down to nanofibers (50-100nm) while still maintaining a range of fiber cross-sections.

Today, there are two common ways of producing nanofibers. The first is by using electrospinning where the polymer stream (solution or melt) is "extruded and drawn" by creating a 20KV voltage differential between the polymer solution and the collector. This method has been used successfully to produce research quantities of nanofibers and find applications for polymers that are not melt-spinnable or solution-spinnable.

Recent research has demonstrated that nanofibers can be produced using melt-spinnable polymers by using conjugate spinning methods and designing special spinpacs. The results have produced nanofibers in the range of 100 nm to 400nm. The advantage of melt-spinning methods for nanofibers is that the productivity is similar to the productivity for other melt-spun fibers. The following images illustrate several of the types of fibers produced by conjugate spinning techniques and further illustrate the range of cross-sectional shapes that are possible with the appropriate spinpac setup.

It can be readily observed that the development of a new range of fibers with cross-sections ranging from circular, segment pied, ribbon as well as other cross-sections permit the incorporation of additional functionality. Furthermore, nanofibers have significant surface areas that can be used to react with the environment. Special monomolecular layers and decreased pore size in the resultant fabrics lead to decontamination and entrapment capabilities. Ribbon fibers, for example, provide low abrasion and low air and water permeability. Hollow segment pie and islands in the sea structures provide micro and nanofibers as fiber blends where functionality of the polymer components can be combined to functional advantage.

The emerging World of nanofibers gives the Textile Materials Technologist an entirely new world of materials and functions to create the next generation of textile materials.

(Select the picture to view for the larger image)