Wearable and Robust Polyimide Hydrogel Fiber Textiles for Strain Sensors

Conductive ionic hydrogel fibers and textiles with excellent mechanical properties and chemical stability are requested for flexible and wearable electronic devices, strain sensors, and even artificial skin. However, most of the reported hydrogel fibers are not suitable in complex environments, especially in alkaline solutions and organic solvents due to their poor chemical stability. Herein, we report ionic polyimide hydrogel fibers derived from an organosoluble polyimide salt that can be continuously and rapidly prepared via a facile wet spinning method. Thanks to their ion-rich property and robust skeletal structure, the obtained ionic polyimide hydrogel fibers showed an excellent conductivity of ∼21 mS/cm and outstanding mechanical properties with a tensile strength of 2.5 MPa and breaking elongation of 215%. Furthermore, the as-prepared fibers could be easily woven to form integral textiles, endowing them with good wearable properties. Accordingly, facile strain sensors assembled by polyimide hydrogel fibers show a linear response with high sensitivity and good cycling stability, which have great potential for applications in wearable and flexible strain sensors under diverse complex environments.