Robust Fluorine-Free Hydrophobic Nanofibrous Composites with High Moisture Absorption toward Comfortable Wearability

High-performance waterproof-breathable nanofibrous membranes are critically needed for wearable applications, yet their development faces persistent challenges including the reliance on fluorinated compounds, the inherent trade-off between waterproofness and moisture permeability, and the insufficient mechanical durability under dynamic conditions. Herein, a fluorine-free silica nanofiber/waterborne polyurethane (SiO2/WPU) composite membrane was prepared via electrospinning and WPU dipping, which features a hierarchical “SiO2 nanofiber skeleton-WPU coating” structure. This design integrates a hydrophilic and moisture-absorbing SiO2 scaffold with a discontinuous stretchable WPU layer, endowing the SiO2/WPU composite membrane with a hydrophobic surface (127.07° water contact angle) while retaining high moisture regain (10.23%), together with a hydrostatic pressure of 3.96 kPa and a water vapor transmission rate of 4.14–5.23 kg m–2 day–1, achieving simultaneous waterproofness, moisture permeability, and moisture absorption without the use of fluorinated chemicals. The SiO2/WPU composite not only overcomes the waterproofing limitations of conventional fluorine-free materials but also attains a comfort level that surpasses most synthetic materials and approaches that of natural cotton. Mechanically, it possesses a tensile strength of 9.39 MPa, an elongation at break of 8.17%, and endures over 120,000 bending cycles, bridging the gap in mechanical endurance for flexible waterproof nanofibrous membranes. This work provides an eco-friendly and structurally innovative pathway to high-performance wearable textiles with enhanced wearing comfort.