Large-Scale Preparation of Polymer Nanofibers for Air Filtration by a New Multineedle Electrospinning Device

Abstract

There are still some challenges for mass-scale production via electrospinning (e-spinning). For example, the cost of industrialized equipment is relatively expensive, and the subsequent maintenance costs are high. The reliability and stability of the production process are also one of the important challenges. The recycling of organic solvents and the volatilization of solvents not only affect the quality of nanofibers, but also causes environmental pollution. In this work, a new multineedle e-spinning device has been proposed for large-scale production of polymer nanofibers. The spinning solution is provided through the outside surface of the needle to avoid needle clogging problem, which is different from the traditional multineedle e-spinning. The successful preparation of thermoplastic polyurethane (TPU) nanofiber membrane with production rate ~50 g h-1 proves the feasibility of the device, which also can be used to prepare other functional nanofibers such as polyvinylidene fluoride (PVDF) and polyacrylonitrile (PAN). The prepared TPU nanofiber gauze has been characterized. The average fiber diameter was 145.3 nm. The surface of the sample was found to be uniform, and the water contact angle was 138.9°. The sample had gas permeability of 1500 mm s-1, excellent PM2.5 removal efficiency of 99.897%, and optical transparency of ~56%, indicating that the new device has a practical application perspective.