Structuring liquids can be achieved by the assembly and jamming of particles at the oil-water interface. However, this typically requires surface modification of particles or co-assembly with polymer ligands to enhance interfacial binding energies. Here, we show a simple and robust strategy to structure liquids by using water-soluble, star-shaped β-cyclodextrin (β-CD) derivatives, whose interfacial assembly is driven by supramolecular interactions with oil solvents. Three classes of solvents including alkanes, aromatic hydrocarbons and halohydrocarbons are examined, leading to distinct interfacial binding energies of β-CD derivatives and different liquid structuring and coalescence behaviors. In aromatic hydrocarbon/water biphasic systems, β-CD derivatives form jammed yet porous interfacial assemblies that combine mechanical rigidity with high free volume. As a result, the liquids are shapeable, reconfigurable and capable of arrested coalescence upon gentle contact, opening opportunities for programmable liquid constructs, soft robots, and related applications. Structuring liquids can be achieved by jamming particles at the oil-water interface, but this can require modification of the particles. Here, the authors report the use of cyclodextrin derivatives to give jammed yet porous packing and therefore mechanical rigidity and high free volume.
Li et al. (2026) studied this question.