PET/TPU nanofiber composite filters with high interfacial adhesion strength based on one-step co-electrospinning

Abstract Nanofiber membranes are widely employed to prepare composite filter media. The traditional composite method of hot pressing may damage the structure of nanofiber membrane, and thus increase the pressure drop through the composite filter. In this study, three-dimensional PET/TPU (polyethylene terephthalate/thermoplastic polyurethane) composite nanofiber filters (PET/TPU-CNF) with beads-on-string structure were fabricated by one-step co-electrospinning. Besides a stronger adhesion strength of 1.385 N/cm between the nanofiber membrane and substrate, the PET/TPU-CNF presented a low pressure drop of 28.96 Pa and a filtration efficiency of 83.64% for ambient particles at a face velocity of 5.3 cm/s. A high tensile strength of 4.33 MPa was measured for the PET/TPU nanofiber membrane. Thanks to the beads-on-string structure, both the mechanical properties and filtration performances of PET/TPU-CNF were enhanced compared with the pure PET nanofiber composite filter. The present study provides a new route to improve the membrane adhesion strength of nanofiber membrane coated filters.