Ultrastrong eutectogels engineered via integrated mechanical training in molecular and structural engineering

Ultrastrong gels possess generally ultrahigh modulus and strength yet exhibit limited stretchability owing to hardening and embrittlement accompanied by reinforcement. This dilemma is overcome here by using hyperhysteresis mediated mechanical training that hyperhysteresis allows structural retarda tion to prevent the structural recovery of network after training, resulting in simply single pre-stretching training. This training strategy introduces deep eutectic solvent into polyvinyl alcohol hydrogels to achieve hyperhysteresis via hydrogenbondingnanocrystalsonmolecularengineering,performssingle pre-stretching training to produce hierarchical nanofibrils on structural engi neering, and fabricates chemically cross-linked second network to enable stretchability. The resultant eutectogels display exceptional mechanical per formances with enormous fracture strength (85.2MPa), Young’smodulus (98 MPa) and work of rupture (130.6MJm−3), which compare favorably to those of previous gels. The presented strategy is generalizable to other sol vents and polymer for engineering ultrastrong organogels, and further inspires advanced fabrication technologies for force-induced self-reinforce ment materials.