The full utilization of discarded wool for the preparation of continuous recycled keratin fibers has been a challenging subject. The key issue lies in how to utilize wool keratin as much as possible without damaging the main chain structure of the protein molecules. Based on small molecule simulation reactions, the authors find out that disulfide bonds, the only cross-linking bonds in keratin, can be effectively broken by starch-derived dithiothreitol, and the resultant keratin can be well separated by the cosmetic ingredient sodium dodecyl sulfate, which forms micelles that stabilize the keratin solution. Accordingly, the traditional strong hydrogen-bond breakers like urea and LiBr can no longer be used, which helps to protect the integrity of keratin. The resultant fully dissolved, highly concentrated keratin solution (keratin content = 18 wt %) is directly applied for wet spinning. To toughen and strengthen the envisaged keratin fibers, a few hydroxypropyl cellulose and glutaraldehyde and 4,4′methylenebis(phenyl isocyanate) are incorporated. Eventually, the regenerated continuous fibers with keratin content as high as 90 wt % offer a combination of properties similar to natural wool.

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We proposed a novel approach to prepare high-performance continuous regenerated keratin fibers with wool-like structure by using the cortical cells and linear keratin from wool waste as reinforcement and adhesive, respectively. The spindle-shaped cortical cells were taken from wool waste based on the different responses of cortical cells and mesenchyme in wool to the treatments of H 2 O 2 oxidation and ultrasonication. The linear keratin was yielded through dissolving wool waste in the green solution consisting of starch derived dithiothreitol and protein denaturant sodium dodecyl sulfate. The recycled keratin fibers were produced by wet-spinning of the mixture solution comprising of cortical cells, linear keratin and toughener poly(ethylene glycol) diacrylate, and crosslinked by glutaraldehyde and 4,4′-methylenebis-(phenyl isocyanate). The cortical cells were aligned along the regenerated fibers axis and retained quite a few α-helical crystals of the intermediate filaments, benefitting improvement of mechanical properties. Consequently, the valuable chemical compositions and hierarchical microstructures of wool were largely inherited. Their mechanical properties, thermal stability, dyeing property, moisture absorption capability, and antistatic resistance resembled those of wool. The regenerated fibers contained 93.3 wt.% components of wool, and the amount of synthetic chemicals in the regenerated fibers was controlled to as low as 6.7 wt.%.

Selenium and tellurium nanorods were synthesised by the reaction of glucose with Na 2 SeO 3 and Na 2 TeO 3 under hydrothermal conditions. The products are characterised in detail by the multiform techniques: X-ray diffraction, energy dispersive X-ray analysis, scanning electron microscopy and transmission electron microscopy. The results show that the selenium products are nanorods with diameters of about 200-300 nm, and lengths ranging between 1 and 3 mm. The diameters of the tellurium nanorods range from 60 to 80 nm and the lengths of several micrometres. The various effects on the growth of nanorods were studied.