TY - JOUR
T1 - Self-assembly of block copolymer micelles in an ionic liquid
AU - He, Yiyong
AU - Li, Zhibo
AU - Simone, Peter
AU - Lodge, Timothy P.
PY - 2006/3/1
Y1 - 2006/3/1
N2 - 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][PF6] solutions exhibit some distinct features, such as temperature-independent micellar morphologies between 25 and 100 °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.
AB - 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][PF6] solutions exhibit some distinct features, such as temperature-independent micellar morphologies between 25 and 100 °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.
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U2 - 10.1021/ja058091t
DO - 10.1021/ja058091t
M3 - Article
C2 - 16492063
AN - SCOPUS:33644648447
SN - 0002-7863
VL - 128
SP - 2745
EP - 2750
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
IS - 8
ER -