Surface modification treatment methods of wool

Growing environmental concerns in recent years have led to finding new resources such as natural fibers, which include lignocellulosic and animal-based materials to replace the synthetic fibers (glass, Kevlar, and carbon fibers), particularly in the development of composite materials. One such new resource is wool. While finding value addition to these natural materials, they may require surface modifications to improve surfaces amenable for their use in developing new materials such as dyed wool polymer composites. In the case of wool fibers, the modification by physical or chemical methods has been successfully attempted to alter the hydrophobic/hydrophilic ratio and facilitate the application of dyes among others. This chapter, starting with a brief about wool fibers, will present some representative modification methods of wool for its industrial uses and new areas of uses to open up new research such as preparation of advanced composites. The surface modification methods include acid or alkaline chemical reactions, incorporation of nanoparticles, microwave radiation, and plasma exposure. The technical concepts, advantages, and disadvantages of each modification method are described, as well as the new research results, considering the environmental aspects and costs. It is hoped the methodologies presented in this chapter will apply to other natural fibers, including those from other animals, to open up new areas of their utilization in a scientific manner enabling new value-added applications for such industrial wastes.