Nanotechnology is the study and development of materials at nano levels. It is one of the rapidly growing scientific disciplines due to its enormous potential in creating novel materials that have advanced applications. This technology has tremendously impacted many different science and engineering disciplines, such as electronics, materials science, and polymer engineering. Nanofibers, due to their high surface area and porosity, find applications as filter medium, adsorption layers in protective clothing, etc. Electrospinning has been found to be a viable technique to produce nanofibers. An in-depth review of research activities on the development of nanofibers, fundamental understanding of the electrospinning process, and properties of nanostructured fibrous materials and their applications is provided in this article. A detailed account on the type of fibers that have been electrospun and their characteristics is also elaborated. It is hoped that the overview article will serve as a good reference tool for nanoscience researchers in fibers, textiles, and polymer fields. Furthermore, this article will help with the planning of future research activities and better understanding of nanofiber characteristics and their applications.

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Continous filament nonwovens are fabrics produced by the direct lay processes, wherein webs are made directly from fibers as they are being spun from molten plastics. These processes eliminate intermediate steps in the production of fabrics, and they provide opportunities for increasing production and cost reduction, although the flexibility in product ranges might be limited. The two important processes in this category are spunbonding and meltblowing. In spunbonding, the fabrics are produced by depositing extruded spun filaments onto a collecting belt followed by bonding of the fibers. There are several process variables that have an impact on the structure and properties of the fibers, and consequently on the structure and properties of the bonded fabric. Although there has been a significant technological advance, the scientific understanding of the process has been limited. Effects of some of these variables have been investigated over the past few years. There has also been some effort to simulate the process by mathematical modeling. A summary of the advances in understanding the evolution of structure and properties during filament formation and thermal bonding is discussed in this paper.

Properties of the point-bonded nonwoven fabrics are dependent on the bonding conditions, in addition to those of the polymer/fiber. Thermally bonded carded webs were produced and characterized to investigate the role of bond area, bond size, and bonding temperature on the structure and properties of point-bonded nonwoven fabrics. It was observed that the bond strength increases with bond area and bond size. The effects of bond area and bond size on fiber morphology were negligible. Significant morphological differences were observed in the bonded and the unbonded regions of the thermally bonded webs. To see how the staple fiber studies relate to the behavior of continuous filaments, similar sets of samples were produced and characterized by using the spunbond system. The observed trends for properties with respect to bonding conditions were similar for spunbond samples.