Keratin proteins are the major components of hair, feathers, wool and horns and represent an important source of renewable raw materials for many applications. The dissolution of the wool keratin is the first step of reuse of keratin wastes. In this work, L-cysteine was applied to the dissolution of wool keratin for the first time as a reducing agent. The dissolution time was 5 h at 75°C with 72% dissolubility. XRD, ATR-FTIR and 13 C NMR showed that the content of α-helix structures in regenerated wool keratin was decreased compared with natural wool. The content of S-S crosslinkages for regenerated wool keratin significantly decreased and broke about 62% of the S-S crosslinkages in the natural wool, as observed from Raman spectra.

Lyocell fiber is a new kind of regenerated cellulose fiber and expected to replace the Rayon fiber to be not only used in the textile field but also used in the fields of industry and aerospace after being modified. In this work, the multi-walled carbon nanotubes (MWNTs)/ Lyocell composite fibers were prepared under different draw ratios by dry-wet spinning and their electrical properties, mechanical properties, and structure were investigated. It was found that an appropriate amount of MWNTs could be dispersed homogeneously in the Lyocell matrix and could improve the mechanical and thermal properties of composite fiber. The results of wide angle Xray diffraction (WAXD) showed that the MWNTs in the composite fiber almost aligned along the axis of the fibers and the orientation of MWNTs increased with the increasing draw ratio. Furthermore, it was found that more MWNTs content and lower draw ratio could improve the electrical conductance of the composite fiber. The composite fiber containing 5 wt % MWNTs has a volume conductivity of 8.8 Â 10 À4 S/cm, which is five orders higher than that of pure Lyocell fiber. These results indicate that the MWNTs/Lyocell composite fiber has potential applications in the areas of precursor of carbon fiber and conductive fiber.

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