Effect of shearing on formation of silk fibers from regenerated Bombyx mori silk fibroin aqueous solution.

In this paper, the spinnable regenerated silk fibroin aqueous solution with high concentration was prepared and the regenerated silk fibers were obtained from the aqueous solution by two different spinning processes at ambient temperature. The orientation of these fibers was characterized by polarizing microscope. Their secondary structure was investigated by Raman spectroscopy and related mechanical properties were also measured. These data showed that shearing is an important step for increasing orientation and silk II (beta-sheet) structure, and the mechanical properties of the regenerated silk fibers can also be improved by shearing.