Superb tough hydrogels based on macromolecule micelles as cross-linkers

These hydrogels generated by macromolecular micelles cross-linking have been attracting a lot of attention due to their excellent mechanical properties. In this paper, Pluronic F127 diacrylate (F127DA) macromolecule micelles were prepared and used as cross-linkers to prepare polyacrylamide (PAM) hydrogels. The effects of the concentration of F127DA micelles on the morphology, swelling behavior and mechanical property of the hydrogels were investigated. The results show that the F127DA micelles cross-linking hydrogels have high strength and extensibility with the elongation at break of 1320%, fracture stress of 528 kPa and toughness of 2.94 MJ m⁻³, which is much higher than chemically cross-linking hydrogels. Cyclic tensile test shows excellent recoverability, indicating that deformation of macromolecule micelles and entanglements of the polymer chains could effectively dissipate energy. (paper)