Shine a light: A supramolecular hydrogel is formed by the glucan curdlan equipped with α‐cyclodextrins (CD‐CUR) and azobenzene‐modified poly(acrylic acid)(pAC12Azo). The sol–gel transition and the morphology of the supramolecular hydrogel can be switched by photoirradiation at the appropriate wavelength, which controls the formation of an inclusion complex between the α‐cyclodextrins and the azobenzene moieties (see picture).

ABA-triblock copolyethers 1a-1c as linear polymeric binders, in combination with clay nanosheets (CNSs), afford high-water-content moldable supramolecular hydrogels with excellent mechanical properties by constructing a well-developed crosslinked network in water. The linear binders carry in their terminal A blocks guanidinium ion (Gu(+)) pendants for adhesion to the CNS surface, while their central B block comprises poly(ethylene oxide) (PEO) that serves as a flexible linker for adhered CNSs. Although previously reported dendritic binder 2 requires multistep synthesis and purification, the linear binders can be obtained in sizable quantities from readily available starting materials by controlled polymerization. Together with dendritic reference 2, the modular nature of compounds 1a-1c with different numbers of Gu(+) pendants and PEO linker lengths allowed for investigating how their structural parameters affect the gel network formation and hydrogel properties. The newly obtained hydrogels are mechanically as tough as that with 2, although the hydrogelation takes place more slowly. Irrespective of which binder is used, the supramolecular gel network has a shape memory feature upon drying followed by rewetting, and the gelling water can be freely replaced with ionic liquids and organic fluids, affording novel clay-reinforced iono- and organogels, respectively.

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Magnetic polyurethane elastomers containing various plasticizers were synthesized, and the effect of plasticizers on the magnetoelastic behavior has been investigated. The storage modulus for magnetic elastomers at 0 mT decreased with plasticizer content, whereas the storage modulus at 500 mT dramatically increased. The increment in the storage modulus by magnetic fields increased with plasticizer content indicating a well-developed chain structure of magnetic particles. It was found that the on-field storage modulus can be scaled by the off-field modulus independently of the kind of plasticizers.