As a result of inherent rigidity of the conjugated macromolecular chains resulted from the delocalized π-electron system along the polymer backbone, it has been a huge challenge to make conducting polymer hydrogels elastic by far. Herein elastic and conductive polypyrrole hydrogels with only conducting polymer as the continuous phase have been simply synthesized in the indispensable conditions of 1) mixed solvent, 2) deficient oxidant, and 3) monthly secondary growth. The elastic mechanism and oxidative polymerization mechanism on the resulting PPy hydrogels have been discussed. The resulting hydrogels show some novel properties, e.g., shape memory elasticity, fast functionalization with various guest objects, and fast removal of organic infectants from aqueous solutions, all of which cannot be observed from traditional non-elastic conducting polymer counterparts. What's more, light-weight, elastic, and conductive organic sponges with excellent stress-sensing behavior have been successfully achieved via using the resulting polypyrrole hydrogels as precursors.

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A stretchable and elastic supramolecular hydrogel with water-responsive shape-memory behavior, which can be realized under mild and green conditions, was developed.

Polyurethane–urea supramolecular hydrogel with excellent mechanical and processible properties is developed. The mechanical properties including shear modulus, elongation at break, tensile strength and compression stress can be adjusted by altering the diisocyanate content.

to now, fabrication of strong and stimuli-responsive supramolecular hydrogels via easy molecular design and synthesis procedure is still a big challenge. In this work, a series of hydrophobicly modified linear polyurethane-urea copolymers and one polyurethane copolymer were prepared via a greatly simplified one-pot approach to investigate the synergistic effect between hydrogen -bonding and hydrophobic effect. FT-IR and various mechanical performance studies show that not only longer hydrophobic spacer (C12) but also stronger hydrogen-bonding unit (urea) are necessary for their synergistic effect to yield high water containing, transparent, stretchy and tough supramolecular hydrogels. Moreover, these supramolecular materials also show nice cyclic shape-memory behaviours which can be realized under mild conditions, e.g. in air and water at room temperature. The noncovalent interaction's synergistic effect and stimuli-responsive character are expected to dramatically expand the design and choice of tough and smart supramolecular hydrogels/materials for biomaterials.