Synergistic Dual Slip‐Link Toughening of a Water‐Rich Double Network Hydrogel Combining Slide‐Ring and Highly Entangled Networks

ABSTRACT Slide‐ring network (SRN) hydrogels derived from ring‐crosslinked polyrotaxanes exhibit exceptional mechanical properties attributable to a pulley effect, whereby mobile‐ring crosslinks redistribute tension under deformation through a slip‐link mechanism. However, SRN hydrogels weaken severely upon swelling in water, limiting their utility at high water content (90 wt.%). Here, two distinct physical slip‐link mechanisms are combined in a highly entangled slide‐ring double network (HESRDN) hydrogel: the pulley effect of a polyrotaxane slide‐ring network and the entangled chains of a sparsely cross‐linked polyacrylamide network. HESRDN is prepared by photopolymerization of acrylamide/ N , N '‐methylenebis(acrylamide) within a partially swollen slide‐ring hydrogel. The dual slip‐link architecture synergistically strengthens and toughens the hydrogel far beyond the sum of the component networks, yielding high work of fracture (1275 kJm −3 ), toughness (2020 Jm −2 ), and near‐complete reversibility (99.7%) at 91 wt.% water. HESRDN withstands continuous friction for over 12 h without rupture, compared to minutes for the SRN and 5 h for the HEN component networks, reflecting the unique capacity of the dual slip‐link architecture to delocalize and redistribute stress under sustained mechanical loading.