Strong, high barrier, water- and oil-resistant cellulose paper-based packaging material enabled by polyvinyl...

Nowadays, plastics are widely used in daily life, but they pose huge threats to both the environment and human health. Therefore, it is imperative to develop green, sustainable and high-performance cellulose-based paper materials to replace plastics. A key challenge for paper-based packaging materials is the need for waterproof and oil-resistant properties. However, most current solutions rely on harmful fluorocarbon coatings or organic solvents, raising safety and environmental concerns. Herein, we present a novel waterproof and oil-resistant coating solution composed solely of polyvinyl alcohol (PVA) and bentonite (BT) nanosheets. When applied to sugarcane paper, this composite paper demonstrates excellent water resistance, with a 64 % water absorption rate, which is 48.4 % lower than untreated paper. Additionally, the composite paper exhibits high mechanical strength (tensile strength: 50.47 MPa, Young's modulus: 3.14 GPa) and superior barrier properties with a water vapor transmission rate of 4.59 g/(m²·24h) and an oxygen transmission rate of 264.959 cm³/(m²·24h·0.1 MPa). Furthermore, this composite paper shows promise in fruit preservation and holds great potential for broader applications in the food packaging industry.