Polymorphic regenerated silk fibers assembled through bioinspired spinning

• Main Authors: Li, Chunmei (Author), Huang, Wenwen (Author), Kaplan, David L. (Author), Ling, Shengjie (Contributor), Qin, Zhao (Contributor), Buehler, Markus J (Contributor)
• Other Authors: Massachusetts Institute of Technology. Department of Civil and Environmental Engineering (Contributor)
• Format: Article
• Language: English
• Published: Nature Publishing Group, 2017-12-11T20:32:23Z.
• Subjects: Article
• Online Access: Get fulltext

A variety of artificial spinning methods have been applied to produce regenerated silk fibers; however, how to spin regenerated silk fibers that retain the advantages of natural silks in terms of structural hierarchy and mechanical properties remains challenging. Here, we show a bioinspired approach to spin regenerated silk fibers. First, we develop a nematic silk microfibril solution, highly viscous and stable, by partially dissolving silk fibers into microfibrils. This solution maintains the hierarchical structures in natural silks and serves as spinning dope. It is then spun into regenerated silk fibers by direct extrusion in the air, offering a useful route to generate polymorphic and hierarchical regenerated silk fibers with physical properties beyond natural fiber construction. The materials maintain the structural hierarchy and mechanical properties of natural silks, including a modulus of 11 ± 4 GPa, even higher than natural spider silk. It can further be functionalized with a conductive silk/carbon nanotube coating, responsive to changes in humidity and temperature.
National Institutes of Health (U.S.) (Grant U01 EB014976)
United States. Office of Naval Research (Grant N00014-16-1-2333)
United States. Air Force Office of Scientific Research (Grant FA9550-11-1-0199)
United States. Air Force Office of Scientific Research (Grant FA9550-14-1-0015)