Touchspinning: Mechanically drawing polyacrylonitrile nanofibers

Abstract Electrospinning is the predominant method of polymer nanofiber production, though the technique is fraught with challenges. Mechanical drawing of nanofibers is a more facile method, but most research in this area produces a small quantity of fibers, unsuitable for scale‐up applications. The touchspinner, a new device made for continuous cold‐drawing of nanofibers, has the potential to produce fiber mats comparable to electrospinning in efficiency but with fewer drawbacks. Initial studies have been performed to characterize the effect of controllable parameters on produced nanofibers. Model polymer polyacrylonitrile was spun out of N,N ‐dimethylformamide into nanofibrous mats via touchspinning while varying the main process controls: solution pump speed, touchspinner rotation speed, and polymer concentration in solution. Nanofibers produced from various combinations of these parameters varied in size from 60 to 3000 nm, and optimal spinning parameters resulted in efficient production of highly aligned nanofibers. Of the three processing controls polymer concentration, and to a lesser degree rotation speed, had the highest impact on the resulting fiber diameters.