Multilayer electrospun nanofibrous membranes with antibacterial property for air filtration

With the aggravation of particulate matter (PM) pollution, critical requirements including intercepting the fine particles effectively and trapping biological pollutants have been proposed for the air filtration material. In this study, multilayer structured membranes with excellent air filtration performance and antibacterial ability were fabricated via sequential electrospinning. A novel N-halamine biopolymer, P(ADMH-NVF), was first synthesized via a free-radical copolymerization of N-Vinylformamide (NVF) and 3-allyl-5,5-dimethylhydantoin (ADMH), and combined with polyvinyl alcohol (PVA) as a middle layer (PVA/P(ADMH-NVF)). Polyvinyl alcohol/ chitosan electrospun membranes (PVA/CS) were then orderly assembled onto both sides of the (PVA/P(ADMH-NVF)) membranes to form multilayer membranes. In the filtration test, the multilayer electrospun nanofibrous membranes showed high filtration efficiencies of 99.3% for sodium chloride (NaCl) and 99.4% for Diisooctyl sebacate (DEHS) aerosol. In addition, the multilayer electrospun nanofibrous membranes hold a relatively low pressure drop of 183 Pa for NaCl and 238 Pa for DEHS aerosol, as well as a high tensile strength of 6.1 MPa. For the antibacterial test, the multilayer electrospun nanofibrous membranes exhibited excellent antibacterial abilities against both Gram-negative bacteria E. coli and Gram-positive bacteria S. aureus. It is expected that these multilayer electrospun nanofibrous membranes containing N-halamine will have wide application prospects in air filtration.