A novel route to prepare dry-spun silk fibers from CaCl2-formic acid solution

Regenerated silk fibroin (RSF) fibers with high strength and extensibility were firstly dry-spun from CaCl2-formic acid (FA) solution. The dissolution of degummed silk in CaCl2-FA was simple and efficient, and featured nanofibril-preservation. The preserved nanofibrils were responsible for the good physical properties of RSF fibers from such a spin solution. The simple and efficient spin process of RSF is very useful in an effort to utilize waste material and produce functional materials, such as biodegradable silk sutures. (C) 2014 Elsevier B.V. All rights reserved.