High-performance fluorine-free waterproof and breathable electrospun nanofibrous membranes by thermally induced coating-crosslinking

To meet the increasing environmental requirements, it is urgent and inevitable for high-performance waterproof and breathable membranes to be fluorine-free. However, developing these membranes faces significant challenges in achieving high water repellency while maintaining desirable water vapor permeability. Herein, we present a high-performance fluorine-free waterproof and breathable membrane using electrospinning technology and a thermally induced coating-crosslinking method. The prepared nanofibrous membrane has low surface energy and crosslinked fiber networks due to hydrophobic group grafting and heat treatment. Benefiting from its microstructure and surface properties, the fluorine-free nanofibrous membrane exhibits excellent hydrophobicity (water contact angle of >130 degrees), desirable pore structure and mechanical strength. Furthermore, the obtained non-fluorinated membrane exhibits excellent water pressure resistance of 95.27 kPa and water vapor permeability of 7.41 kg m(-2) d(-1). Meanwhile, the crosslinking agent enhances the bond between the non-fluorinated hydrophobic modifier and the substrate, increasing the stability and robustness of the membrane. This study provides guidance for designing and preparing environmentally friendly waterproof and breathable membranes, with extensive application prospects in outdoor sports, healthcare protection and building exteriors.