Fig. 4: Fatigue-resistance of different hydrogels.

Crack extension dc/dN per cycle versus applied energy release rate G of a IV15SH, b AV15H, c AV15SH, d AV15SH-90 and e AV15SH-120. f Summary of fatigue thresholds (Γ0) of different hydrogels. g Photographs of the notched sample at cycle numbers of 5000 and 10,000 for validation of the fatigue threshold as high as ~1856 J m−2 for AV15SH-120. Fatigue thresholds data are presented as mean values ± SD, n = 3 independent samples. h Diagram of fatigue threshold versus fracture strength for different hydrogels. i Schematic representation of the anti-fatigue mechanism of the anisotropic hydrogels.