ABSTRACT
Nanofiber technology is a branch of nanotechnology whose primary objective is to create materials in the form of nanoscale fibers in order to achieve superior functions. The unique combination of high specific surface area, flexibility, and superior directional strength makes such fibers a preferred material form for many applications ranging from clothing to reinforcements for aerospace structures. Although the effect of fiber diameter on the performance and processibility of fibrous structures has long been recognized, the practical generation of fibers at the nanometer scale was not realized until the rediscovery and popularization of the electrospinning technology by Professor Darrell Reneker almost a decade ago [1]. The ability to create nanoscale fibers from a broad range of polymeric materials in a relatively simple manner using the electrospinning process, coupled with the rapid growth of nanotechnology in recent years have greatly accelerated the growth of nanofiber technology. Although there are several alternative methods for generating fibers in a nanometer scale, none matches the popularity of the electrospinning technology due largely to the simplicity of the electrospinning process. Electrospinning can be carried out from polymer melt or solution. A majority of the published work on electrospinning has been focused on solution-based electrospinning rather than on melt electrospinning due to higher capital investment requirements and the difficulty in producing submicron fibers by melt electrospinning. We will concentrate on solution-based electrospinning in this chapter. Specifically, after an introduction to the processing principles the relative importance of the various processing parameters in solution electrospinning is discussed. The structure and properties of the fibers produced by the electrospinning process are then examined. Recognizing the enormous increase in specific fiber surface, bioactivity, electroactivity, and enhancement of mechanical properties, numerous applications have been identified, including filtration, biomedical, energy storage, electronics, and multifunctional structural composites.
