One-step fabrication of mechanically robust and fluorine-free nanofiber membranes for waterproofness and breathability

Waterproof and breathable membranes (WBMs) find widespread uses in various fields, such as garments, buildings, medical supplies, and electronic devices. Yet, the addition of fluorinated materials and complex post-treatment processes often restricts their practical use. Here, we report an in-situ inter fiber bonding structured fluorine-free polyurethane/poly(styrene-butadiene-styrene)/polydimethylsiloxane (PU/SBS/PDMS) nanofiber membrane with robust mechanical properties using a one-step electrospinning technique. The incorporation of PU significantly enhanced the spinnability and mechanical properties of SBS, while the in-situ introduction of PDMS provided the necessary waterproofness and improved inter fiber bonding. The resulting membrane exhibited satisfactory waterproofness, with a hydrostatic pressure of 58.95 kPa, and moisture permeability of 4.38 kg m^-2 d^-1 (upright cup method). Additionally, it also exhibited excellent mechanical properties with a tensile strain of 352.5%, breaking stress of 10.04 MPa, and impressive toughness of 19.94 MJ m^-3. These intriguing attributes make it an ideal choice for wearable and textiles, particularly those products requiring high durability and comfortability. The successful fabrication of mechanically robust membranes opens a new avenue for developing eco-friendly and high-performance functional textiles.