Comparison of the effects of post-spinning drawing and wet stretching on regenerated silk fibers produced through straining flow spinning

Abstract

Straining Flow Spinning is a versatile and robust spinning technique for the production of regeneratedsilkworm silkfibers using mild chemistries. However, reaching high values of tensile strength and strainat breaking requires a step ofwet-stretchingin water, which limits scalability and the practical usage ofthe technique. Here, we show that adding apost-spinning drawingstep to the procedure improves theperformance of thefibers, and allows the development of a scalable process. It is also shown that theproperties of thefiber can be tuned by varying the parameters of the post-spinning step. Finally,equivalence is established between the discrete wet-stretching process and the continuous post-spinning drawing step.