Rheology and Spinnability of Polyvinylpyrrolidone Solutions

We examine spinnability and centrifugally-spun fiber properties for polyvinylpyrrolidone (PVP) by first focusing on the influence of molecular weight and dispersity, and the choice of solvent. A small fraction of high molecular weight (UHMW) PVP is incorporated to illustrate extensibility-enriched spinnability and highlight how nearly similar shear, but quantitatively stronger and different extensional rheology response changes the spinnability outcomes. To elucidate the influence of solvent properties, we vary ethanol content in spinning dope comprising aqueous PVP solutions. We rely on a bespoke centrifugal force spinning (CFS) set-up that allows spinning from two symmetrically placed nozzles onto a collector using matched processing parameters, but variable polymer-solvent concentrations.