Jianfeng Wang

Achieving recyclable materials that simultaneously exhibit high mechanical strength and long‐lasting hydrophobicity remains a fundamental challenge, as dynamic or supramolecular systems typically suffer from compromised robustness or water resistance. Here, we report a layered material that integrates nacre‐like multiple interactions to overcome this trade‐off. The material is constructed from vermiculite nanosheets and a functional copolymer through evaporation‐induced assembly followed by thermal annealing, which triggers a ring‐closing transformation of polymer side chains. This process generates π–π interactions and hydrogen‐bonding networks that impart durable hydrophobicity, while strong Al─O─C coordination bonds at the organic–inorganic interface enable efficient load transfer and high mechanical strength (≈ 154 MPa). Importantly, these interactions are selectively and reversibly disrupted via an ammonia‐mediated ring‐opening reaction, allowing the material to be chemically cleaved and reprocessed into films with near‐original performance. The resulting system exhibits a rare combination of high strength, stable hydrophobicity (water contact angle ≈ 95°), and closed‐loop recyclability. This work establishes a biomimetic strategy for synergistically integrating multiple interactions in confined architectures, offering a general design principle for next‐generation sustainable structural materials.

Hydrogels, water‐rich polymer networks, are important materials for application as structural biomaterials. More water‐rich networks are typically less mechanically robust, which is manifested as softness and low stress to fracture. Unusually, jellyfish mesoglea exhibits paradoxical combination of high stiffness and strength with ultrahigh water content. Here, it is discovered that jellyfish mesoglea possesses a long‐range‐ordered laminated membranous network, which features crystal orientation along membrane plane and collagen chain spanning at the junction of membranes. Such a laminated membranous network is in favor of resistance to deformation, as well as transmission and dispersion of stress for culminating in good mechanical robustness. Fabrication of chitosan hydrogel with jellyfish mesoglea‐like network is further demonstrated by pre‐constructing a random membranous network via evaporation‐induced phase separation, followed by aligning and crystallizing the membranes via combination of in‐plane stretching and sodium hydroxide treatment. The obtained hydrogel exhibits a combination of high modulus (5.2 MPa) and strength (6.5 MPa) with ultrahigh water content (91.8 wt.%), exceeding that of other synthetic and even biological hydrogels. This work offers not only a structural concept but also a feasible way for making hydrogels that overcome traditional trade‐off between good mechanical robustness and ultrahigh water content.

Modern electronic systems are evolving toward miniaturized designs, flexible architectures, and high-power-density requirements. However, progress in developing electrical insulation materials that integrate mechanical robustness, flexibility, and thermal stability remains a critical challenge. This study introduces a novel nacre-inspired aramid-vermiculite nanopaper featuring a 3D interconnected layered network, designed for use in flexible electrical insulating applications. By embedding high-aspect-ratio vermiculite nanosheets within a three-dimensional aramid nanofiber network, we fabricated a high-strength, high-toughness electrical insulating nanopaper via a continuous sol-gel-film conversion method. The resulting nanopaper exhibits exceptional mechanical properties, achieving a tensile strength of 186 MPa, a work of fracture of 55 MJ m^-3, and a strain-to-failure of 38.6%. Furthermore, it demonstrates high dielectric strength (193 kV mm^-1) and nonflammable characteristics. The bioinspired vermiculite-based nanopaper displays superior electrical breakdown resistance and flame retardancy, highlighting its potential for advanced electrical insulation applications. The fabrication process and microstructural analysis reveal the importance of the 3D interconnected layered structure in achieving these enhanced properties.

Hydrogels, provided that they integrate strength and toughness at desired high content of water, promise in load-bearing tissues such as articular cartilage, ligaments, tendons. Many developed strategies impart hydrogels with some mechanical properties akin to natural tissues, but compromise water content. Herein, a strategy deprotonation-complexation-reprotonation is proposed to prepare polyvinyl alcohol hydrogels with water content as high as ~80% and favorable mechanical properties, including tensile strength of 7.4 MPa, elongation of around 1350%, and fracture toughness of 12.4 kJ m⁻². The key to water holding yet improved mechanical properties lies in controllable nucleation for refinement of crystalline morphology. With nearly constant water content, mechanical properties of as-prepared hydrogels are successfully tailored by tuning crystal nuclei density via deprotonation degree and their distribution uniformity via complexation temperature. This work provides a nucleation concept to design robust hydrogels with desired water content, holding implications for practical application in tissue engineering.

Natural nacre's hierarchical brick-and-mortar architecture motivates intensive studies on inorganic platelet/polymer multilayer composites, targeting mechanical property enhancement only by two strategies: optimizing the size and alignment of inorganic platelets and improving the interfacial interaction between inorganic platelets and polymers. Herein, a new strategy of polymer chain orientation to enhance the property of bioinspired multilayered composites is presented, which facilitates more stress to be transferred from polymer layers to inorganic platelets by simultaneous stiffening of multiple polymer chains. To this end, bioinspired multilayer films consisting of oriented sodium carboxymethyl cellulose chains and alumina platelets are designed and fabricated by three successive steps of water evaporation-induced gelation in glycerol, high-ratio prestretching, and Cu²⁺ infiltration. Regulating the orientation state of sodium carboxymethyl cellulose leads to a large enhancement of mechanical properties, including Young's modulus (2.3 times), tensile strength (3.2 times), and toughness (2.5 times). It is observed experimentally and predicted theoretically that the increased chain orientation induces failure mode transition in the multilayered films from alumina platelet pull-out to alumina platelet fracture because more stress is transferred to the platelets. This strategy opens an avenue toward rational design and manipulation of polymer aggregation states in inorganic platelet/polymer multilayer composites and allows a highly effective increase in modulus, strength, and toughness.

Highlights: A self-grinding exfoliation strategy that depends on mutual shear friction between flake graphite particles is successfully developed to prepare pristine graphene with largely enhanced yield and productivity. Bioinspired assembly of pristine graphene nanosheets to an interconnected aramid nanofiber network is achieved by a continuous sol-gel-film transformation strategy and generates a flexible yet highly thermoconductive film. Flexible yet highly thermoconductive materials are essential for the development of next-generation flexible electronic devices. Herein, we report a bioinspired nanostructured film with the integration of large ductility and high thermal conductivity based on self-exfoliated pristine graphene and three-dimensional aramid nanofiber network. A self-grinding strategy to directly exfoliate flake graphite into few-layer and few-defect pristine graphene is successfully developed through mutual shear friction between graphite particles, generating largely enhanced yield and productivity in comparison to normal liquid-based exfoliation strategies, such as ultrasonication, high-shear mixing and ball milling. Inspired by nacre, a new bioinspired layered structural design model containing three-dimensional nanofiber network is proposed and implemented with an interconnected aramid nanofiber network and high-loading graphene nanosheets by a developed continuous assembly strategy of sol–gel-film transformation. It is revealed that the bioinspired film not only exhibits nacre-like ductile deformation behavior by releasing the hidden length of curved aramid nanofibers, but also possesses good thermal transport ability by directionally conducting heat along pristine graphene nanosheets. Graphical

Developing high-performance materials from existing natural materials is highly desired because of their environmental friendliness and low cost; two-dimensional nanoclay exfoliated from layered silicate minerals is a good building block to construct multilayered macroscopic assemblies for achieving high mechanical and functional properties. Nevertheless, the efforts have been frustrated by insufficient inter-nanosheet stress transfer and nanosheet misalignment caused by capillary force during solution-based spontaneous assembly, degrading the mechanical strength of clay-based materials. Herein, a constrained assembly strategy that is implemented by in-plane stretching a robust water-containing nanoclay network with hydrogen and ionic bonding is developed to adjust the 2D topography of nanosheets within multilayered nanoclay film. In-plane stretching overcomes capillary force during water removal and thus restrains nanosheet conformation transition from nearly flat to wrinkled, leading to a highly aligned multilayered nanostructure with synergistic hydrogen and ionic bonding. It is proved that inter-nanosheet hydrogen and ionic bonding and nanosheet conformation extension generate profound mechanical reinforcement. The tensile strength and modulus of natural nanoclay film reach up to 429.0 MPa and 43.8 GPa and surpass the counterparts fabricated by normal spontaneous assembly. Additionally, improved heat insulation function and good nonflammability are shown for the natural nanoclay film and extend its potential for realistic uses.