Ultra‐Stretchable, Self‐Healing, Conductive, and Transparent PAA/DES Ionic Gel

Abstract A deep eutectic solvent (DES) ionic gel is fabricated rapidly under mild conditions. The acrylic acid monomer is polymerized based on a dual self‐catalytic system between Vitamin C (VC) and metal ions, such as Fe 3+ in the presence of ammonium persulfate in the DES of betaine and ethylene glycol. The as‐obtained PAA/DES ionic gel possesses excellent conductivity between 0.1 and 1.3 S m −1 in a wide range of temperatures from 0 to 90 °C. Moreover, it also shows an ultra‐stretchable performance with stretch more than 200 times its original length even under a stretching rate of 100 mm min −1 . Besides, it can operate in harsh conditions because of its anti‐freezing and anti‐drying properties. The ionic gel is self‐healing, and the stretching and conductive performance can be recovered after it is broken. These superior properties of the DES ionic gel provide new insights into the design of novel gels in various applications, such as tissue engineering, sensing, and wearable electronics.