Synthesis of superamphiphobic breathable membranes utilizing SiO2 nanoparticles decorated fluorinated polyurethane nanofibers

Superamphiphobic nanofibrous membranes exhibiting robust water/oil proof and breathable performances were prepared by the combination of a novel synthesized fluorinated polyurethane (FPU) containing a terminal perfluoroalkane segment and incorporated SiO2 nanoparticles (SiO2 NPs). By employing the FPU/SiO2 NPs incorporation, the hybrid membranes possess superhydrophobicity with a water contact angle of 165° and superoleophobicity with an oil contact angle of 151°. Surface morphological studies have indicated that the wettability of resultant membranes could be manipulated by tuning the surface composition as well as the hierarchical structures. The quantitative hierarchical roughness analysis using N2 adsorption method has confirmed a major contribution of SiO2 NPs on enhancing the porous structure, and a detailed correlation between the fractal dimension and amphiphobicity is proposed. Furthermore, a designed concept test shows that the as-prepared membranes could load 1.5 kg water or oil at the same time maintained an extremely high air permeability of 2 L min−1, suggesting their use as promising materials for a variety of potential applications in protective clothing, bioseparation, water purification, tissue engineering, microfluidic systems, etc., and also provided new insight into the design and development of functional hybrid membranes based on FPU.