Free-standing, robust, hyperconnective hybrid nanofiber nonwovens enabled by interpenetrating network for oily aerosols purification

The key to achieving nanofiber nonwovens with desirable structural stability and hyperconnective networks primarily hinges on the manipulation of the interactions between fibers. Here, we propose a facile approach for developing nanofiber nonwovens with a dual-crosslinked interpenetrating network (IPN) for oily aerosols filtration. Hyperconnective polyester/cellulose acetate (PET/CA) interpenetrating nanofiber nonwovens (IPNN) with extensive interactions among fibers and robust stability are fabricated via one-step electrospinning followed by dual-crosslinking technique. The crosslinking treatments do not change the characteristics of the nonwovens, such as nanofiber shape (diameter of 0.39 +/- 0.04 mu m), porosity (94.95 %) and pore size (1.53 mu m). Importantly, the IPNN displays distinctive interfibrous anchored points reminiscent of spider-capture-silk webs with periodic knots, enabling a high capability for collecting oily aerosols. Simultaneously, the nonwovens exhibit excellent mechanical properties (strength of 28.01 MPa and elongation of 57.94 %) and robust structural stability. Remarkably, the IPNN shows special wettability (water contact angle of 127 degrees and vegetable oil wetting time of 0.25 s) and demonstrates capillary oil migration characteristics (30 mm in 180 s). These properties contribute to exceptional oily aerosols filtration performance, including low filter resistance (106 Pa), high filter efficiency (99.87 %), and superior reusability for long-term operation. This study affords an innovative and promising method for the development of free-standing nanofiber nonwovens with broad applications in high-performance filtration.