Enhancing Waterproof Food Packaging with Janus Structure: Lotus Leaf Biomimicry and Polyphenol Particle Technology...

With the increasing demand for improved food preservation, conventional waterproof food packaging has proven inadequate because of its limited functionality. Although incorporating features such as antibacterial and antioxidant properties into packaging enhances protection, it can compromise the hydrophobicity of the involved material, thereby increasing the risk of contamination from external sources. To address this challenge, a robust and reliable barrier capable of simultaneously integrating multiple protective functions is required. This research synthesizes polyphenol particles via metal ion coordination and multiple hydrogen bondings to enhance antioxidant and antimicrobial properties. In addition, inspired by the asymmetric wettability of Janus-structured lotus leaves, this study develops biomimetic multifunctional Janus electrospun fibers via electrostatic spinning. These fibers exhibit exceptional properties, including superhydrophobic, antifouling, ultraviolet-blocking, pH sensitivity, antioxidation, antimicrobial, and freshness retention properties. Experiments and mesoscopic capillary flow simulations elucidate the waterproofing ability and underlying mechanisms of the Janus electrospun fibers, demonstrating their function as hydrophobic shields for preventing water penetration. Overall, this study provides a reference for high-performance waterproof food packaging to enhance vegetable preservation.