Polymeric nanofibers via flat spinneret electrospinning

Abstract

Electrospun nanofibers are most often produced by needle electrospinning process, which has inherent disadvantages like clogging and low efficiency. In this study, an alternative needleless electrospinning process is reported for the fabrication of nanofibers based on a novel spinneret. Firstly, a spinneret with a 0.5‐mm diameter hole in the middle of a flat plastic cap was custom‐made that may be readily scaled up for mass production. Then, polyethylene oxide (PEO) aqueous solution with 6.0 wt% concentration was used to demonstrate the needleless electrospinning process. The processing window for the jet formation in the flat spinneret electrospinning process was determined. The relationships between various processing parameters (applied voltage, working distance, and flow rate) and the resultant PEO nanofibers were also investigated. It was found that stable fluid jet launched from the tip of the coned droplet anchored at the rim of the hole and formed fibers. The morphology and diameter of electrospun fibers were examined using scanning electron microscopy. The results show that PEO nanofibers produced by this needleless electrospinning have similar structure and morphology to those from the single needle source. Finally, the hole number of spinneret was increased to four holes, which was still able to produce smooth nanofibers with a higher production rate. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers

Needle and needleless electrospinning for nanofibers

“…16,20 A novel spinneret, the ''flat spinneret electrospinning (FSE)'', has recently been developed in the University of Manchester. 22 This uses a flat plastic spinneret to produce polymeric nanofibers. The advantages of FSE over SNE include more uniform electric field and ease of scaling-up.…”

Raising Nanofiber Output: The Progress, Mechanisms, Challenges, and Reasons for the Pursuit

“…In this technique, instead of the spinnerets having miniature protruding nozzles, polymer jets are generated from holes dug in the spinneret surface (porous matrix) . Application of holes in electrospinning has demonstrated better electric field distribution across the geometry compared to their multinozzle counterparts .…”

Solvent-free preparation of polylactic acid fibers by melt electrospinning using umbrella-like spray head and alleviation of problematic thermal degradation

“…However, solution electrospinning has some disadvantages: 1) some solvents are expensive and extremely hazardous to the environment, and thus, must be recovered through highly complicated retrieval processes; 6 2) in the spinning process, the capillary are often blocked, hence seriously affecting the continuity of spinning; 7 3) it is difficult to find suitable solvents for some polymer, such as poly(propylene) and polyethylene, when spun at ambient temperatures although it is not relevant to this current study; 4) the evaporation of the solvent in the spinning process can leave defects on the fiber, leading to relatively low mechanical strength 8 and 5) the concentration of the solution is low, and its corresponding evaporation greatly reduces the yield and production efficiency.…”