Design of tough hydrogels maintaining structural integrity under multivariable mechanical loads remains hugely challenging because the anticipated characteristics such as stretchability, strength, toughness, and fracture resistance can hardly be compatible. Herein, a simple but robust hydrogel network formed by copolymerization of divinyl benzene with acrylamide in micellar solutions for ultra‐high fracture resistance and self‐recoverable stretchability is proposed. The network provides dynamic association of hydrophobic domains and homogeneous crosslinking of hydrophilic chains, which shows step‐by‐step deformation process. The dynamic associations allow recoverable small deformations, then the homogeneous crosslinking ensures reversible unfolding and alignment of polymer chains to self‐strengthen for ultra‐large deformations without crack propagations. The resultant hydrogels exhibit comprehensive unbreakable feature with self‐recoverable ultra‐high stretchability (100% recovery from 10 200% strain), superior fracture resistance (toughness > 26 kJ m−2), and anticrack propagation and fatigue (fatigue threshold: ≈2.5 kJ m−2). Even the prenotched hydrogels can undergo tens cyclic loads at 10 200% strain and thousands cyclic loads at 200% strain without noticeable changes in mechanical performance. The robust network prepared from homogeneous hydrophobic crosslinking provides a facile approach and a new mechanism to explore tough hydrogels with superior antifracture and extreme self‐recoverable deformability for diverse applications.

Design of hydrogels with superior flexible deformability, anti‐fracture toughness, and reliable environment adaption is fundamentally and practically important for diverse hydrogel‐based flexible devices. However, these features can hardly be compatible even in elaborately designed hydrogels. Herein soft hydrogel networks with superior anti‐fracture and deformability are proposed, which show good adaption to extremely harsh saline or alkaline environments. The hydrogel network is one‐step constructed via hydrophobic homogenous cross‐linking of poly (sodium acrylate), which is expected to provide hydrophobic associations and homogeneous cross‐linking for energy dissipation. The obtained hydrogels are quite soft and deformable (tensile modulus: ≈20 kPa, stretchability: 3700%), but show excellent anti‐fracture toughness (10.6 kJ m−2). The energy dissipation mechanism can be further intensified under saline or alkaline environments. The mechanical performance of the hydrophobic cross‐linking topology is inspired rather than weakened by extremely saline or alkaline environments (stretchability: 3900% and 5100%, toughness: 16.1 and 17.1 kJ m−2 under saturated NaCl and 6 mol L−1 NaOH environments, respectively). The hydrogel network also shows good performance in reversible deformations, ion conductivity, sensing strain, monitoring human motions, and freezing resistance under high‐saline environments. The hydrogel network show unique mechanical performance and robust environment adaption, which is quite promising for diverse applications.

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