Investigation of Microstructures and Air Permeability of Aerogel-Coated Textile Fabric Materials

This study focuses on fabrication of aerogel-coated macroporous polyester fabrics for the purposes of filtration of nanometric airborne particles and potential application in facemasks. Syndiotactic polystyrene (sPS) and polyimide (PI) gels that provide respectively majority macropores (diameter > 50 nm) and mesopores (diameter 2 to 50 nm) are coated onto woven polyester fabrics via a dip coating process. The resultant materials are supercritically dried to obtain aerogelcoated fabrics. The results show that sPS is more suitable for the dip coating process. However, evaporation of the solvent during handling of gel-coated fabrics leads to closure of the surface pores that are later recovered via solvent annealing. The resultant aerogel-coated fabrics offer high air permeability (∼10 –10 m 2 ) and high filtration efficiency (> 99.95%) of airborne sodium chloride test particles of size 25 to 150 nm.