Effect of solvent on the physical and morphological properties of poly(lactic acid) nanofibers obtained by solution blow spinning

Abstract

Solution blow spinning (SBS) is a simple, safe, and inexpensive alternative to electrospinning for making nanofibers from polymer solutions. However, since SBS is a relatively new technique, there is a general lack of information on polymer solutions and properties that affect fiber morphology and intrinsic properties. The present study reports the solution properties of poly (lactic acid) (PLA) dissolved in chloroform, dichloromethane, and dichloroethane at 4%, 6%, or 8% (w/v) and the properties of fibers made by SBS. In contrast to 4% polymer solutions, fibers made from 6% polymer solutions had few beads and diameters in the range of 120-320 nm. Diameters were greater (311-570 nm) for fibers made from 8% polymer solutions. Solvent evaporation rate affected the fiber porosity and formation. Hansen solubility parameters indicate that dichloromethane was the solvent most miscible with PLA. Fibers made with PLA in dicloromethane had the broader range in fiber diameter. Hansen parameters could be a valuable predictive tool for identifying highly miscible polymer/solvent systems for the SBS process. Polymer solutions with high viscoelasticity and viscosity were well suited for the SBS process. Fibers made from polymer solutions containing dichloromethane had lower crystallinity compared to fibers made from the other solvents.