Lotus Leaf-Inspired Multi-Component Nanofibrous Membranes for Waterproof and Breathable Materials

Abstract

Waterproof and breathable membranes (WBMs) are in high demand owing to their promising applications in outdoor protective clothing, medical hygiene, and membrane distillation. Therefore, preparing WBMs with robust waterproofing, breathability, and mechanical properties is necessary. In this study, we report a simple but effective strategy for designing WBMs by combining multicomponent electrospinning with the construction of a lotus-leaf bionic hydrophobic structure. We created multi-component electrospun composite fibrous membranes with high waterproofness and breathability, comprising a spinnable polyvinylidene fluoride (PVDF)-based elastomer, polyurethane (PU), low-surface-energy fluorinated polyurethane (FPU), and polydimethylsiloxane (PDMS). Specifically, we constructed a binary composite structure combining conventional nanofibers and beaded nanofibers via electrospinning and finally realized a lotus leaf surface structure. The lotus leaf bionic structure of the multi-component WBMs demonstrated good surface hydrophobicity and excellent mechanical elasticity. The resulting WBMs exhibited multifunctional properties with a robust hydrostatic pressure (104.7 kPa), high water contact angle (152°), good water vapor transmission rate (5.084 kg m^‒2 d^‒1), upright cup method, and tensile strength (11.4 MPa). This simple preparation process provides new ideas for the design and manufacture of waterproof and breathable films for various applications.