Rational Design of Polycationic Hydrogel with Excellent Combination Functions for Flexible Wearable Electronic Devices

With the popularization of intelligent terminals and the improvement of medical level, the development of flexible wearable electronic devices (FWEDs) with high sensitivity and excellent mechanical properties plays a vital role in human motion and health monitoring. But most of FWEDs still stuck in a difficult choice of mechanical, functional, and sensory properties. In this work, it is found a strategy for extricating such plight. Using zwitterionic and quaternary ammonium salt, a novel polycationic hydrogel [P(ImSL-AmC)] with excellent performance is synthesized by copolymerization under photoinitiation. After optimizing conditions of synthesis, its structure and properties are characterized. It is found that the electrostatic interaction enhances the mechanical applicability of P(ImSL-AmC), which combines high stretchability (approximate to 500% strain) with perfect strength (approximate to 900 kPa) successfully. It is exciting that P(ImSL-AmC) not only exhibits excellent antibacterial activities against both E. coli and S. aureus, but also maintains transparency and flexibility at -10 degrees C. This polycationic hydrogel also has superior conductivity as a stretchable pressure-strain sensor, which can accurately monitor human motion. In summary, the obtained polycationic hydrogel possesses excellent combination functions, including intelligent conductivity, mechanical adaptability, antibacterial, frost resistance, and transparency. Furthermore, the practical strategy can be applied in preparation of intelligent wearable devices and human-computer interaction.