Direct functionalization of natural silks through continuous force-reeling technique

Abstract

Compared with synthetic polymer fibers, animal silks have apparent advantages of sustainability, mechanical properties, and air and humidity permeability. However, the functionalization of animal silk at a single fiber scale is not yet fully developed. Herein, a low-cost, effective, and scalable strategy was developed to functionalize the native silk by combining continuous force-reeling and dip-coating techniques. With this approach, conductive and color-programmable silk with extremely long length (larger than one kilometer), high mechanical performance (with a strength of 516 ± 66 MPa, toughness of 114 ± 25 MJ m−3, comparable to spider dragline silk), and good interface bonding between silk and functional layer were developed. These functionalized silks were directly used as a highly sensitive mechanical sensor in extreme environments, such as in liquid nitrogen and water. In addition, these fibers were automatically woven into large-scale washable dynamic coloring and luminous fabrics. These intelligent fabrics exhibit rapid, programmable, and recyclable thermochromic and electroluminescent responses, showing promising applications in dynamical textile displays.