title: Nanodroplet cluster formation in ionic liquid microemulsions.
abstract: A common ionic liquid (IL), 1-butyl-3-methylimidazolium tetrafluoroborate (bmimBF(4)), is used as polar solvent to induce the formation of a reverse bmimBF(4)-in-toluene IL microemulsion with the aid of the nonionic surfactant Triton X-100. The swelling process of the microemulsion droplets by increasing bmimBF(4) content is detected by dynamic light scattering (DLS), conductivity, UV/Vis spectroscopy, and freeze-fracture transmission electron microscopy (FF-TEM). The results show that the microemulsion droplets initially formed are enlarged by the addition of bmimBF(4). However, successive addition of bmimBF(4) lead to the appearance of large-sized microemulsion droplet clusters (200-400 nm). NMR spectroscopic analysis reveal that the special structures and properties of bmimBF(4) and Triton X-100 together with the polar nature of toluene contribute to the formation of such self-assemblies. These unique self-assembled structures of IL-based microemulsion droplet clusters may have some unusual and unique properties with a number of interesting possibilities for potential applications.
authors.affiliation: Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106 Magdeburg, Germany.
authors.forename: Yanan
authors.initials: Y
authors.lastname: Gao
authors.forename: Andreas
authors.initials: A
authors.lastname: Voigt
authors.forename: Liane
authors.initials: L
authors.lastname: Hilfert
authors.forename: Kai
authors.initials: K
authors.lastname: Sundmacher