Pilot-scale production of polylactic acid nanofibers by melt electrospinning

Abstract

<jats:title>Abstract</jats:title><jats:p>Melt electrospinning has been used to manufacture fibers with diameters in the low micrometer range, but the production of submicrometer fibers has proven more challenging. In this study, we investigated the feasibility of fabricating polylactic acid nanofibers using polymer grades with the increasing melt flow rates (15–85 g/10 min at 210°C) by melt electrospinning with a 600-nozzle pilot-scale device featuring an integrated climate control system realized as a glass chamber around the spinneret. Previous experiments using this device without appropriate climate control produced fibers exceeding 1 µm in diameter because the drawing of fibers was inhibited by the rapid cooling of the polymer melt. The integrated glass chamber created a temperature gradient exceeding the glass transition temperature of the polymer, which enhanced the drawing of fibers below the spinneret. An average fiber diameter of 810 nm was achieved using Ingeo Biopolymer 6252, and the finest individual fiber (420 nm in diameter) was produced at a spin pump speed of 5 rpm and a spinneret set temperature of 230°C. We have therefore demonstrated the innovative performance of our pilot-scale melt-electrospinning device, which bridges the gap between laboratory-scale and pilot-scale manufacturing and achieves fiber diameters comparable to those produced by conventional solution electrospinning.</jats:p>

The Investigation of the Structure and Properties of Ozone-Sterilized Nonwoven Biopolymer Materials for Medical Applications

“…ES has already proven itself as an effective way to produce continuous fibers with a large variation in diameter [ 12 , 13 ]. The diversity of ES techniques for solution or melt modes enables modifying the fiber surface morphology and controlling the functional behavior of the resulting micro- and nanomaterials [ 14 , 15 ].…”

Electrospun nanofibers for medical face mask with protection capabilities against viruses: State of the art and perspective for industrial scale-up

“…5 e, f). Shorter interjet distance can be obtained by applying high electric fields during the spinning process as well as by lowering the value of the polymer melt viscosity by varying the nozzle temperature [ 117 , 124 , 125 ]. Despite the high-rate production, the resulting fibers are still large, exceeding 1 μm in size than those fabricated by means of solution ES methods.…”

Semi‐Woven Structures via Dual Nozzle Melt Electrowriting

“…Fiber-producing techniques similar to MEW have addressed processing speed by use of electrostatic deflection of polymer solutions, [10] or by random deposition of polymer melts using circularly aligned needleless nozzles, [11,12] linearly aligned jets produced by slot spinners, [13,14] multiple Taylor cones from melting of a polymer sheet with a laser beam, [15] or nozzle arrays, [16,17] including 600 nozzles. [18,19] The combination of solvent-free melts and precise positioning of fibers has so far remained elusive. Translating a multi-jet approach to MEW has presumably not been reported due to technical challenges in developing the required hardware or perhaps due to the perception that multiple jets will deleteriously impact each other.…”