Water-Resistant Poly(vinyl alcohol)/ZnO Nanopillar Composite Films for Antibacterial Packaging

To solve the problems that poly(vinyl alcohol) (PVA) easily breeds bacteria and swells in a humid environment, PVA and ZnO nanopillar (ZnO NP) components were composed to generate PVA/ZnO NP composite films via a simple combination process of blending and heat treatment in this study. Here, ZnO NPs endowed composite films with good antibacterial properties, and the etherification and dehydration of hydroxyl groups between PVA molecular chains induced by heat treatment resulted in the composite films having excellent water-swelling resistance. Most importantly, PVA/ZnO NP composite films revealed excellent tensile strength in both humid (52.85 MPa) and dry (74.63 MPa) environments. In addition, PVA/ZnO NP composite films showed good antibacterial and antisepsis abilities as well as preservation functions in the packaging test of half-cut apples. The current work disclosed an easy strategy for producing a PVA-based antibacterial film for packaging materials that are water-resistant and highly strong, making them suitable for applications in humid environments.