Role of jet path on uniformity of electrospun nanofibers

This paper reports on the role of jet path in obtaining uniform and bead free nanofibers during electrospinning process. Polyethylene oxide (PEO) nanofibers were electrospun by varying the molecular weight of PEO and concentration of poly allylamine hydrochloride (PAH) in the spinning solution. Different modes of fiber formation were captured by a camera and analyzed further by image processing technique in order to assess their influence in the formation of uniform and bead free nanofibers. Two different jet paths during fiber formation, namely straight and whipping were assessed. The length of the straight jet path during the fiber formation played a major role in the formation of uniform nanofibers in comparison to the length of the whipping path. The diameter and surface morphology of the nanofibers were characterized by SEM. Nanofibers spun using higher concentration of PAH exhibited longer straight jet path and therefore more uniform nanofibers in comparison to that spun at lower concentration of PAH. Flow simulations of the electrically charged polymer solutions were carried out to observe the changes in the solution flow rate and Taylor cone shape. Increased flow rate and changes in the Taylor cone shape with the increasing PAH concentration in low molecular weight polymer were observed.