3D-printed stretchable sensor based on double network PHI/PEDOT:PSS hydrogel annealed with cosolvent of H2O and DMSO

3D-printed stretchable sensors have promising applications in wearable devices, human–computer interaction, soft robotics, and many other fields. However, low conductivity and poor stretchability still hinder their extensive applications. Herein, we report a strategy of double networks and annealed PEDOT:PSS for the first time. The new material combines mechanical stretch performance and conductivity together, where 3D-printed complex stretchable poly(2-hydroxyethyl acrylate-isobornyl acrylate) (PHI) structure serves as the tough network and annealed highly conductive PEDOT:PSS serves as the functional network. It is adopted to build 3D-printed porous stereo structures with both stretchability and conductivity. It exhibits interconnected uniform networks, improved storage modulus (1.3 * 10 6  Pa), higher conductivity (The conductivity of PHI/PEDOT: PSS annealed is up to 3.12 * 10 −1  S m −1 , which is 441 times compared to PHI/PEDOT: PSS), excellent stability and durability at a large strain of 60%. Hence, it is expected that this new strategy will open up wide possibilities for designing stretchable sensors and smart devices.