Self-Assembly of Block Copolymer Micelles in an Ionic Liquid
- 2 February 2006
- journal article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 128 (8), 2745-2750
- https://doi.org/10.1021/ja058091t
Abstract
Four amphiphilic poly((1,2-butadiene)-block-ethylene oxide) (PB-PEO) diblock copolymers were shown to aggregate strongly and form micelles in an ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF(6)]). The universal micellar structures (spherical micelle, wormlike micelle, and bilayered vesicle) were all accessed by varying the length of the corona block while holding the core block constant. The nanostructures of the PB-PEO micelles formed in an ionic liquid were directly visualized by cryogenic transmission electron microscopy (cryo-TEM). Detailed micelle structural information was extracted from both cryo-TEM and dynamic light scattering measurements, with excellent agreement between the two techniques. Compared to aqueous solutions of the same copolymers, [BMIM][PF(6)] solutions exhibit some distinct features, such as temperature-independent micellar morphologies between 25 and 100 degrees C. As in aqueous solutions, significant nonergodicity effects were also observed. This work demonstrates the flexibility of amphiphilic block copolymers for controlling nanostructure in an ionic liquid, with potential applications in many arenas.Keywords
This publication has 30 references indexed in Scilit:
- Self-Assembly of a Nonionic Surfactant at the Graphite/Ionic Liquid InterfaceJournal of the American Chemical Society, 2005
- Ionic Liquid-in-Oil MicroemulsionsJournal of the American Chemical Society, 2005
- Polarity of ionic liquids determined empirically by means of solvatochromic pyridinium N-phenolate betaine dyesGreen Chemistry, 2005
- Cope's Rule, Hypercarnivory, and Extinction in North American CanidsScience, 2004
- A new type of polymer gel electrolyte: zwitterionic liquid/polar polymer mixtureElectrochimica Acta, 2003
- Catalytic Activity of Supported Au Nanoparticles Deposited from Block Copolymer MicellesJournal of the American Chemical Society, 2003
- Micellar Polymers with Hydrocarbon and Fluorocarbon Hydrophobic Chains. A Strategy to Multicompartment MicellesMacromolecules, 2002
- Characterization and comparison of hydrophilic and hydrophobic room temperature ionic liquids incorporating the imidazolium cationGreen Chemistry, 2001
- Block Copolymer Lithography: Periodic Arrays of ~10 11 Holes in 1 Square CentimeterScience, 1997
- A constrained regularization method for inverting data represented by linear algebraic or integral equationsComputer Physics Communications, 1982