fig8

Figure 8. Flexible hybrid hydrogel-based pressure sensors. (A) Schematic illustrating the formation process of a PAAM-CNF hybrid hydrogel interpenetrating network with catechol-quinone groups formed on its surface and its self-healing and UV-blocking properties. Reproduced with permission^[124]. Copyright 2021, American Chemical Society. (B) Schematic illustrating the composition of the CS-PHEAA DN hydrogel with good mechanical, ionic conductive and freezing-tolerant properties. Reproduced with permission^[125]. Copyright 2021, Elsevier. (C) Schematic illustrating the composition and fabrication of a composite hydrogel and photographs showing its properties. Reproduced with permission^[127]. Copyright 2020, American Chemical Society. PAAM: polyacrylamide; CNF: cellulose nanofibril; UV: ultraviolet; CS: chitosan; PHEAA: poly(hydroxyethyl methacrylate); DN: double network.