Fig. 1. Topoarchitected polymer networks (TPNs).

a Existing elastomers and hydrogels (equilibrium-swollen in water) exhibit a negative correlation between two properties: elastic limit strain and toughness. The TPNs synthesized in this work simultaneously achieve high elastic limit strain and high toughness. b In a fascicle of an Achilles tendon, staggered collagen fibrils are embedded in a proteoglycan matrix. c Schematic illustration of TPNs. Hard blocks adhere to a soft matrix through topological entanglement of polymer networks. d Mechanical principle of a staggered-patterned TPN for high elasticity and high toughness. e TPN hydrogels prepared by sequential polymerization and photolithography.