(666a) Hydrophobic and Water-resistant Lignocellulosic Packaging Materials Enabled by Metal Ion Modification

Lignocellulosic paper is an essential solution for preventing the increase in plastic packaging wastes; however, the inherent hydrophilicity and poor water resistance hinder its practical applications. Herein, we developed a facile metal-ion-modification approach for converting conventional hydrophilic, low-wet-strength lignocellulosic paper to hydrophobic and water-resistant paper with high wet strength. In this process, conventional paper is swelled with a dilute multivalent metal ion (e.g., Fe3+, Zr4+) solution, followed by drying to induce the coordination interactions between metal ions and lignocellulosic fibers. The resulting hydrophobic paper exhibits a water contact angle up to 140°, good wet tensile strength, and a low water absorptiveness of 10 g/m2. Hydrophobic paper is stable for long-term storage and solvent wash. This metal-ion-modification approach can potentially be applied in the wood pulping process for the scalable production of hydrophobic fibers and paper.