Highly Elastic Slide-Ring Hydrogel with Good Recovery as Stretchable Supercapacitor.

As a new material with excellent mechanical properties and good stability, slide-ring gels have attracted attention and research. However, they cannot be widely used due to their relatively complicated synthesis. Herein, we use 6-acrylamidomethylether-modified α-cyclodextrin (αCDAAmMe) and PEG20000 diacrylate (PEG20000 DA) to construct a polypseudorotaxane. Then, the polypseudorotaxane reacts with acrylamide via a photo-initiated polymerization in situ to conveniently obtain a slide-ring hydrogel with good elastic property and high recovery property. The hydrogel can be easily stretched to 22.5 times of its original length but recovered rapidly and almost reversibly. These results enable the application of hydrogel to make an intrinsically stretchable and compressible supercapacitor after doping ions and the adhesion of commercially available carbon nanotube (CNT) paper as electrodes, giving the ionic conductivity of 17.0 mS cm-1 (comparable to that of the commercial PVA/H3 PO4 electrolyte) and the capacitance of 0.87 μF cm-2 (at the scan speed of 100 mV s-1 ), and its capacitance can be further enhanced under stretching.