Fig. 28 (a) Preparation of hexaarylbiimidazole hydrogels and UV-triggered dimerization of
hexaarylbiimidazole moieties, (b) UV-induced deformation of photosensitive HABI-containing
gel (left) and bisphenol A-based gel (right). Adapted with permission [68]. Copyright 2017,
American Chemical Society
Fig. 29 (a) Preparation of azobenzene-boronic acid hydrogels and UV-triggered boronic ester
formation, (b) rheological test showing storage modulus (black) and loss modulus (red) behavior of
P1/P2 under UV, (c) visual self-healing experiments. Adapted with permission [73]. Copyright
2018, The Royal Society of Chemistry
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