Multiscale Tendon–Mimetic Hydrogel Structures Via the Cascading Synergy of Chemical Microphase Separation and Mechanical Twisting–Weaving

Natural tendon provides an ideal multilength‐scale network structure design for loading‐bearing soft materials. Despite many recent advances, it remains challenging to fully imitate their multiscale architectures to effectively leverage their collaborative force sharing capacity. Herein, we propose to fuse the chemical microphase separation and mechanical twisting–weaving approaches to devise robust multiscale tendon–mimetic hydrogel structures. First, cosolvent‐induced microphase separation is employed to uniformly disperse the rigid metal‐coordinated poly(acrylamide‐co‐sodium 6‐(3‐(2‐(methacryloyloxy)ethyl)ureido)pyridinecarboxylate) (PA6M) phases into the soft hydrophilic polyurethanes (PU) network. This architecture enables significant energy dissipation through the plastic deformation of hard/soft phases and reversible dissociation of abundant metal coordination and hydrogen‐bonding interactions, yielding enhanced fracture energy (13.7 kJ/m 2 ) and high toughness (28.7 MJ/m 3 ). Second, the mechanical twisting–weaving is developed to transform these tough hydrogels into hydrogel fibers that can be further weaved into 2D/3D hydrogel structures. Such weaving hydrogel structures are found to optimize the distribution of forces to avoid excessive stress concentration for significantly increasing the overall load‐bearing stability, ultimately achieving an effect where the total load‐bearing capacity of the whole woven structure exceeds the sum of the capacities of several individual hydrogel fibers under the tested weaving configuration.