Langmuir, Vol.26, No.11, 8887-8892, 2010
Pluronic Micelle Shuttle between Water and an Ionic Liquid
We demonstrate an effective micelle shuttle between water and a hydrophobic ionic liquid and its application in transportation in the biphasic system, using a commercially available and inexpensive Pluronic block copolymer. The poly(ethylene oxide-h-propylene oxide-h-ethylene oxide) (PI23) block copolymer self-assembles into micelles in both water and the ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate, as characterized by dynamic light scattering. The poly(ethylene oxide) blocks provide the well-solvated corona, whereas the poly(propylene oxide) blocks form the solvophobic core. The micelles can spontaneously transfer between the two phases upon a simple temperature stimulus; the transfer is reversible and repeatable, and H-1 NMR analysis indicates quantitative transfer. The micelle nanocarriers are used to transport various cargoes in the biphasic system: fully reversible transport of hydrophobic small organic dyes into and out of water and facile extraction of an ionic liquid-phobic polymer from the ionic liquid. This simple round-trip delivery system may be used in delivery, separations, and extraction in synthesis and biphasic catalysis involving ionic liquids.