Fig. 4.

a Photographs of C₁₁T₄A₂₀ hydrogel adhered on diverse substrates. b Schematic illustration of the lap shear test. c Photograph of lap shear test using pigskin as substrate. d Representative stress − displacement curves of lap shear tests on glass, wood, plastic, Al, and pigskin glued by C₁₁T₄A₂₀ hydrogel. e Adhesive strength and reusability of C₁₁T₄A₂₀ hydrogel on various substrates. f Adhesion durability and stability of C₁₁T₄A₂₀ hydrogels on pigskin demonstrated by 20 successive peeling-off cycle tests. g Proposed adhesion mechanism between CTA hydrogel and various substrates. h, i Photographs of C₁₁T₄A₂₀ hydrogels conformally self-adhered to the body’s frequently moving joints