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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.

Despite the market demand for biofiber assemblies endowed with superhydrophobicity being huge, the current approaches to their production are complicated, time-consuming, and even pose a serious threat to the environment. Here, we report a simple surface treatment strategy to prepare environmentally friendly superhydrophobic biofiber composites. The obtained samples have certain UV resistance properties, which are mainly determined by the titanium dioxide (TiO2) dosage. Additionally, the sample has excellent thermal stability, and the contact angle is maintained at 153.26° after heat treatment at 140 °C for 1 h. Quite encouragingly, thermal annealing of samples can transform translucent coatings into transparent structures and increase the tensile strength. The results also showed that this strategy could be integrated into the mass production process of other biofiber components as coating, such as coated paper, pulp boards, cotton gauzes, tissues, and so forth. Due to the facile preparation and environment-friendliness, this sustainable paper-based product can be used in diversified applications: packaging and storage of liquid food, protection of ancient books, UV- and rain-proof materials, and teaching demonstrations relevant to bionics, among others.

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In this paper, the double-element composites were developed, which contained the epoxy resin as matrix phase and carbon black rubber powder as toughening materials. Quasi-static compression tests on epoxy resin and different mass fractions carbon black rubber powder-epoxy resin composites were performed in room temperature to test their compression properties. The energy absorption performance and the energy absorption efficiency of the composites were calculated according to the compression curve. The fracture characteristics of the micro appearance of the compressed material specimen were observed by scanning electron microscope. The deformation mode of the composite was analyzed. By systematically analyzing the effects of carbon black rubber powder content on the mechanical properties of carbon black rubber powder-epoxy resin, it was found that carbon black rubber powder as a reinforced material could effectively improve the brittleness of epoxy resin, the yield strength and the adsorption properties and efficiency of composites. With the mass fraction of carbon black rubber powder increasing, the energy absorption performance of carbon black rubber powder-epoxy resin first increases and then decreases. The most significant performance observed was at a mass fraction of 5 % in carbon black rubber powder-epoxy resin composites.