Large Strain Hysteresis and Mullins Effect of Tough Double-Network Hydrogels

Systematic loading and unloading experiments, in uniaxial tension and uniaxial compression, have been performed on a double-network hydrogel exhibiting a very high toughness. We observed a significant hysteresis during the first loading cycle that increased strongly with the applied maximum deformation. A large hysteresis was not observed during a second loading cycle, implying that the initial hysteresis can be attributed to the fracture of...