Fig. 2: Design approaches for enhancing the strength and toughness of PVA ionic gels.

a Tensile stress-strain curves of PVA organogels salted out with NaCl, NH4SO4, C6H5Na3O7, and [Bmin]BF4. b Comparison of tensile strength and fracture strain. c Comparison of toughness and Young’s modulus. d Tensile stress-strain curves of PL-gel pre-stretched to 0%, 25%, 50%, and 75%. e Comparison of tensile strength and fracture strain. f Comparison of toughness and Young’s modulus. g Tensile stress-strain curves of organogel and PL-gel samples with and without notches. h Comparison of toughness and Young’s modulus between PL-gel and other reported gels. i Comparison of toughness and tensile strength between PL-gel and other reported gels. Data in (b, c, e, f) are presented as their means ± SDs from n = 3 independent samples.