Bioinspired Paper-Based Nanocomposites Enabled by Biowax- Mineral Hybrids and Proteins

Paper-based products are similar to paper wasps' nests built by biofiber separation and biofiber reassembly, where they add saliva for structural reinforcement and waterproofing. Rice leaves, which contain lignocellulosic components and look like paper sheets, have functional epidermises for directional self-cleaning and defensive barriers. We herein report a bioinspired concept of forming functional nanocomposites from environmentally friendly additives and cellulosic paper. Beeswax-silica hybrids mimic rice leaves' mineralized biowaxy epidermises. Gelatin, which is chemically similar to protein-containing saliva of paper wasps, acts as a functional additive to facilitate anchorage of hybrids to paper and to consolidate/waterproof the composite structures. Thermal annealing reorganizes as-formed composites and induces the formation of transparent coatings. As expected, the consolidated nanocomposites show self-cleaning superhydrophobicity. The processes of spraying biowax-mineral hybrid dispersion onto gelatin-deposited substrate followed by thermal annealing are integrable into unit operations of paper production as surface sizing or coating. Other features of the strategy would involve antibacterial properties and fruits/vegetables preservation. This simple, bioinspired strategy would direct sustainable paper-based products toward diversified applications: food/drinks containers or packaging materials that can reduce or eliminate liquid wastes, preservation of historic/artistic works, scientific demonstrations relevant to surface engineering and bionics, and children-related safe products, among others.