Multi-responsive organo- and hydrogelation based on the supramolecular assembly of fluorocarbon- and hydrocarbon-containing hybrid surfactants.

Hypothesis: Novel photoresponsive hybrid surfactants, in which a combination of perfluoroalkyl and alkyl chains and cationic head groups are connected via azobenzene moieties, are excellent candidates for assembling low-molecular-weight organogels (LMOGs) with reversibly switchable viscoelasticities triggered by external stimuli.

Experiments: The structure-composition-property relationships of gels assembled with the hybrid surfactants were investigated by UV-vis and NMR spectroscopy, SEM, XRD, and rheology.

Findings: Hybrid surfactants containing perfluorohexyl chains with more than six carbons gelled in a variety of organic solvents at concentrations of less than a few percent.

Synthesis and surface activity of photoresponsive hybrid surfactants containing both fluorocarbon and hydrocarbon chains.

Hypothesis: Hybrid surfactants containing both alkyl and fluoroalkyl chains within the same molecule where modification of the azobenzene group will enable us to switch the superhydrophobic nature with an external light source, and the optical behavior will vary depending on the structure of the hydrophobic chains.

Experiments: Surface activity and its optically-induced variation of the azobenzene-modified hybrid surfactants were characterized using the surface tensiometry, UV-vis and NMR spectroscopy and theoretical calculation.

Findings: The hybrid surfactants are superhydrophobic in nature reducing the surface tension of water to near 20 mN/m.