Flexible ionic conductors based on polymerized deep eutectic solvent reinforced by hydroxyethyl cellulose

Flexible ionic conductors with excellent mechanical properties , stability and conductivity from green and efficient fabrication technology have great application potentials in the intelligent devices. In this work, we reported an ionic conductor fabricated from the polymerization of the polymerizable deep eutectic solvent (PDES) reinforced by the hydroxyethyl cellulose (HEC). The PDES with the cationic hydrogen bond acceptor as the polymerizable unit was synthesized from the methacrylate of the 2-choline bromide (ChBrMA) as hydrogen bond acceptor and the glycerol (Gly) as hydrogen bond donor. The PDES has solubility to dissolve the HEC and thus the HEC-reinforced poly (PDES) ionic conductors were successfully prepared by one step photopolymerization . The addition of HEC enhanced the mechanical strength of poly (PDES)-based ionic conductor. The ionic conductors present the characteristics of good elasticity, puncture resistance, heat resistance and low volatility, and their electrical conductivity reached 2 × 10 −2  S/m at room temperature . Finally we assembled a flexible sensor which can accurately detect the movement of human fingers and monitor the change of environmental temperature in real time, demonstrating their potentials in the multifunctional sensors with long-term durability.