Fig. 4. Paintable ability, mechanical properties, and self-healing performance of the CAHPs.
a Photos of the preparation process and paintable performance of the CAHPs. b Representative extrusion force–displacement curve of the CAHPs. c Injection force of the CAHPs (n = 5 independent experiments). d Young’s modulus of the CAHPs (n = 3 independent experiments). e, f Tensile (e) and compressive (f) stress–strain curves of the CAHPs. g Compressive and tensile modulus of the CAHPs (n = 3 independent experiments). h Representative loading–unloading tensile curves of CAHP-12% at a frequency of 1 Hz and deformation of 25% for 50,000 cycles. i The photos show that the CAHPs could rapidly self-heal and remain connected under stretching. Dynamic covalent borate ester bonds predominantly mediated the self-healing properties. j Modulus self-healing properties of the CAHPs when the alternate step strain was switched from 10 to 400%. k Comparison between the CAHP and other conducting polymer hydrogels13,14, 16, 29, 30 in terms of their injection, modulus, anti-fatigue, self-healing, and adhesion properties. PVA: polyvinyl alcohol, f-PANi: functionalized polyaniline, CAHP chronological adhesive hydrogel patch. Data are presented as the mean ± standard deviation in (c, d, g).