A Vitrimer‐Like Elastomer with Quadruple Hydrogen Bonding as a Fully Recyclable Substrate for Sustainable Flexible Wearables

Abstract Wearable flexible electronics (WFE) have great potential in health management and personalized medicine; however, their rapid development has led to a sharp increase in electronic waste, leading to environmental risks. Although previous studies have proposed the use of degradable polymers, such a WFE is disposable. Therefore, the design of recyclable WFE is promising, but the relevant works have been limited. Herein, a vitrimer‐like polyurethane elastomer containing dynamic ureidopyrimidinone quadruple hydrogen bonding units (PU‐UPy) is developed as a recyclable substrate for a sustainable WFE. The PU‐UPy elastomer is flexible and tough with a tensile strength of 24.4 MPa, a maximum tensile strain of 2950%, and a toughness of 228 MJ m − 3 , satisfying the mechanical requirements for WFE. Moreover, the thermally‐induced dynamic nature of the hydrogen bonds donated by UPy units makes PU‐UPy recyclable via both solid and solvent reprocessing. By creating microstructures via shape reconfiguration, the PU‐UPy and electrode layers are assembled into pressure‐sensing WFE, enabling motion monitoring and Morse code recognition. Furthermore, the assembled WFE can be fully recycled by facile solvent reprocessing; the recycling and reassembly could be repeatable, and the WFE still maintains good pressure‐sensing performance. Overall, this work provides inspiration for the development of sustainable WFE from dynamic polymers.