Melt-electrospinning of poly(ether ether ketone) fibers to avoid sulfonation

Publication date: Available online 20 March 2019Source: PolymerAuthor(s): Nelaka Dilshan Govinna, Thomas Keller, Christoph Schick, Peggy CebeAbstractWe have successfully electrospun un-sulfonated fibers of poly (ether ether ketone), PEEK, from the molten state at 350 °C. Unlike solution electrospinning of PEEK, which produces sulfonated fibers with reduced thermal stability, melt electrospinning produces chemically unaltered PEEK fibers. These fibers are smooth, defect-free, and round in cross-section. Most fiber diameters range from 1.5 μm to 8.5 μm. A large interstitial fiber with diameter reaching up to 100 μm is occasionally deposited at the end of the spin. As-spun oriented amorphous fibers, having diameters less than 10 μm, were selected for fast scanning calorimetric studies of the glass transition and melting behavior. Dynamic fragility of melt electrospun oriented amorphous PEEK fibers and amorphous PEEK quenched from the molten state, was evaluated according to Moynihan's method of cooling at variable rates then reheating at a fixed rate and are found to be 200 ± 5 and 150 ± 5, respectively. These results suggest that orientation in the amorphous state of electrospun fibers plays a role in the dynamics of glass formation.Graphical abstract

Source: Polymer - March 22, 2019 Category: Chemistry Source Type: research