Robust Hydrogel Adhesive with Dual Hydrogen Bond Networks.

Hydrogel adhesives are attractive for applications in intelligent soft materials and tissue engineering, but conventional hydrogels usually have poor adhesion. In this study, we designed a strategy to synthesize a novel adhesive with a thin hydrogel adhesive layer integrated on a tough substrate hydrogel. The adhesive layer with positive charges of ammonium groups on the polymer backbones strongly bonds to a wide range of nonporous materials' surfaces.

Ultra-stretchable hydrogels with hierarchical hydrogen bonds.

Hydrogels are attractive for applications in intelligent soft materials and flexible electronics. Herein, we report a new hydrogel with a hierarchical hydrogen bond system consisting of (1) weak hydrogen bonds between N,N-dimethylacrylamides (DMAA) and acrylic acids (AAc) and (2) strong multiple hydrogen bonds between 2-ureido-4[1H]-pyrimidinone units. By optimizing the ratios of DMAA and AAc and the balance of weak and strong hydrogen bonds, the hydrogels have unique properties.

Thermo-modulated Hela cell release from an elastic and biocompatible hydrogel.

Cell growth and release from the hydrogel scaffolds are critical steps in cell culture and cell therapies. Herein a double network hydrogel with one thermosensitive P(AEtMA-Cl-DEAEA) network and the other polyacrylamide network is reported. The diad hydrogel is elastic and maintains its structural integrity under large deformation.