Influence of a perfluorohexane-enriched atmosphere on the viscoelasticity and structural order of self-assembled nanodomains of semifluorinated alkanes at the air/water interface
Authors: Mielke S, Abuillan W, Veschgini M, Liu X, Konovalov O, Krafft MP, Tanaka M
CellNetworks People: Tanaka Motomu
Journal: Chemphyschem. 2019 May 13. doi: 10.1002/cphc.201900316

Semifluorinated alkanes FnHm self-assemble into nanometer-sized surface micelles at the air/water interface. In this study, we investigated how an atmosphere enriched with perfluorohexane (PFH) influences the interfacial viscoelasticity and structural order of a monolayer of FnHm by the combination of dilational rheology and grazing-incidence small-angle X-ray scattering (GISAXS). The monolayers behaved predominantly elastic which can be attributed to the strong dipole repulsions of the surface domains. Enrichement of the atmosphere with PFH lead to an increase of the compressibility and a decrease of the elastic modulus without altering the structural ordering of the FnHm molecules into highly correlated nanodomains, suggesting the adsorption of PFH molecules to the free spaces between the domains. The capability of FnHm domains to retain the structural integrity in the presence of fluorocarbon gas is promising for the fabrication of stable microbubbles for sonographic imaging.