Nylon-6/SiO2 composite fiber membranes with 2D narrow pore but 3D fluffy structure for high-efficiency and comfortable PM0.1 filter

Particulate matter (PM) contamination constituted a significant threat to both human well-being and the worldwide ecological system. However, protective masks achieved high-performance filtration of the PM by tightly stacking fibers, especially for PM 0.1 , which seriously affected the wearing comfort. Herein, a Nylon-6/SiO 2 composite fiber membrane with two-dimension (2D) narrow pore but 3D fluffy structure was designed to harmoniously combine high-performance filtration capabilities with comfort. Based on one-step multi-jet free-surface air-jet spinning and spraying, the introduction of nano-SiO 2 spheres enhanced the surface roughness of the fiber and reduced the pore size of the 2D fiber layer in the membrane structure, improving PM 0.1 particle capture. Additionally, the addition of micro-SiO 2 spheres could construct a fluffy 3D reticular architecture in the membrane, enhancing the flow of air and minimizing gas resistance during the filtration process. Due to the structural design featuring small pores and low packing density, the Nylon-6/SiO 2 -NM membrane exhibited an excellent PM removal rate of 99.99 % and low air resistance of 101 Pa at the flow rate of 32 L/min. At the flow rate of 85 L/min, the filtration efficiency of 99.9 % could be achieved, and the gas resistance was 254 Pa, the performance conformed to the GB 19083-2011. Moreover, the Nylon-6/SiO 2 -NM mask simultaneously possessed superior wearing comfort with air permeability (277.09 mm/s) and moisture permeability (196.50 g·m −2 ·h −1 ) and UV protection (UPF value of 136), as well as good thermal comfort. This research had the potential to introduce a fresh perspective on developing advanced, high-performance, and user-friendly personal protective materials.