Supramolecular Interlocking Produces Mechanically Anisotropic, Robust, and Tough Biomimetic Ionogels

Ionogels have garnered significant attention in various cutting-edge fields due to their tunable mechanical properties and remarkable multifunctionality. However, current ionogels still struggle to achieve a combination of mechanical robustness and tissue-like anisotropy, hindering their application in next-generation intelligent biomimetic materials. Inspired by the anisotropic structure of tendons, we have embedded parallel-aligned rigid fiber bundles within a flexible ionogel to establish a tight interfacial bonding through supramolecular interlocking. This design enables the dispersion of stress and dissipation of energy through shear deformation of the ionogel in the parallel direction while maintaining high flexibility and stretchability in the perpendicular direction. Thus, tough anisotropic composite ionogels (ACIGs) can be constructed, which exhibit high strength, high modulus, as well as pronounced strength and stiffness anisotropies. The mechanical properties and anisotropies far surpass those of current anisotropic gel materials. Additionally, ACIG demonstrates excellent crack resistance, a wide operational temperature range, and high adhesiveness. It can serve as a biomimetic ligament to secure artificial joints, maintaining stability even after 10 000 bending cycles. Moreover, the conductive properties enable ACIG to function as a sensor for detecting joint movements and transmitting information, holding significant application potential in fields such as intelligent equipment and wearable devices.