Fig. 3: Anisotropic responsiveness in all-polarity solvents.

a Schematic illustrations and corresponding optical images of anisotropic deformations of ASPC hydrogel in different solvents triggered by stimuli of light and solvent. b Relative changes of the ASPC hydrogel parallel and perpendicular to the AgNW/SA lamellae in water under thermal and NIR stimuli and in n-hexane under NIR stimuli. c Relative changes of the ASPC hydrogel parallel and perpendicular to the lamellae triggered by successive stimuli of ethanol and water. d Time-dependent swelling ratio of the ASPC hydrogel parallel and perpendicular to the lamellae in water over 180 days. e A summary of swelling ratio of ASPC hydrogel perpendicular to the lamellae in 11 solvents with different polarities after 180 days (low), and deformation (black sphere) and recovery rates (red sphere) of ASPC hydrogel after 100 days-swelling in different solvents under different stimuli (upper). f Ashby chart plotting anti-swelling stability versus solvent polarity of ASPC hydrogels compared with previously reported works. The pink, orange, purple, blue, cyan, green and yellow spheres represented hydrogels with H-bonding⁴⁵, ionic crosslinking⁴⁶, nanocomposite⁴⁷, double network⁴⁸, hydrophobic association⁴⁹, multi-crosslinking⁵⁰ and gradient structure⁵¹ as anti-swelling mechanisms, respectively. g Cyclic stability of stimuli-responsive performance of ASPC hydrogels after swelling in different solvents for 100 days over 100 cycles. h Comparison of deformation (square) and recovery (sphere) rates (deformation/recovery ratio divided by the time) of ASPC hydrogel with previously reported works.