Designing and Development of Innovative N95 Respirator Using Nanofibres Produced by Air-Assisted Electrospinning

N95 respirators generally have high filtration efficiency with lower air resistance due to the presence of a melt-blown layer, which stores electrostatic charge and provides additional particle capturing. The electrostatic charge present in the melt-blown layer drops significantly in the moist environment and adversely affects the respirator's performance. Therefore, the primary purpose of this study is to design and develop an innovative N95 respirator with a nanofibre membrane to replace the melt-blown layer. Air-assisted electrospinning, having higher productivity than conventional electrospinning, was selected for nanofibre production. A unique air-assisted electrospinning setup, producing continuous nanofiber membranes at the rate of 1.50 cm/min, was used in this study. In the first phase, process parameters of air-assisted electrospinning of polyacrylonitrile (PAN) were optimized using the Taguchi L9 orthogonal array experimental design. The optimized process parameters are the PAN solution concentration of 8% v/w, air pressure of 1.95 kPa, applied voltage of 32 kV, and polymer flow rate of 11 μL/s. In the second phase, a five-layer N95 respirator was developed by replacing the melt-blown layer used in commercial N95 respirators with nanofibre membrane layers. Both the filtration efficiency and air resistance of the developed respirator are almost equal to those of commercial respirators.