Barrier coating integrated with lignin nanotube and polyvinyl alcohol for variety packaging film

Advanced multifunctional green packaging barrier coating hold profound significance for product preservation and environmental sustainability. Considering the increasing requirement on barrier properties, the lignin nanotubes (LNTs) and polyvinyl alcohol (PVA) were adopted to fabricate coating lamina in this study. The obtained composite barrier coating with 1.0 wt% LNT content presented optimum water vapor transmission rate (WVT) of 12.06 g/m²·24 h, and oxygen transmission rate (OTR) of 0.58 cm³/m²·24 h·0.1 MPa, which decreased 57.02 % and 55.38 % respectively compared with pure PVA. The robust hydrogen bonding network between LNT and PVA significantly enhances the composite coating's mechanical properties (38.23 MPa of tensile strength at 2.0 wt% LNT) and thermal stability, which strengthening structure validated by molecular simulations. Crucially, the inclusion of LNT imparts near-complete UV-shielding efficacy and exceptional antimicrobial performance, achieving a 99.30 % inhibition rate against staphylococcus aureus. This composite coating is adaptive for combination with variety base materials in food and medicine packaging, which provides a promising safe and biodegradable barrier coating candidate.