The effect of cation structure on the mesophase architecture of self-assembled and polymerized imidazolium-based ionic liquids.

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Macromol. Chem. Phys.

DOI:https://doi.org/10.1002/macp.200700174· OSTI ID:915333

Batra, D; Seifert, S; Firestone, M A

The binary phase behavior of a series of imidazolium-based ionic liquids (ILs) has been investigated. In particular, the effect of two structural modifications of the imidazolium cation, alkyl chain length, and the introduction of a polymerizable acryloyl group at the alkyl chain terminus, has been studied using small angle X-ray scattering. Upon increasing water content, the non-polymerizable IL, 1-decyl-3-methylimidazolium chloride, adopts mesophase structures of predominately two-dimensional (2D) hexagonal symmetry, including structures intermediate in character between lamellae and 2D hexagonal micelles. Introduction of a photopolymerizable acryloyl functional group to form 1-(10-(acryloyloxy)decyl)-3-methylimidazolium chloride produces a rod-coil IL cation that yields self-assembled mesophases in which the formation of tetragonal morphologies is favored. Covalent linking of the IL cations by UV-induced polymerization converts the lyotropic mesophase into three-dimensional biocontinuous chemical gels. Reducing the alkyl chain length, as in the polymerizable IL cation 1-(8-(acryloyloxy)octyl)-3-methylimidazolium chloride, severely reduces the self-assembled mesophase order, and triggers the formation of only weakly ordered one-dimensional lamellar structures.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: SC
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 915333
• Report Number(s): ANL/MSD/JA-59496
• Journal Information: Macromol. Chem. Phys., Journal Name: Macromol. Chem. Phys. Journal Issue: 2007 Vol. 208
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CATIONS
CHLORIDES
IMIDAZOLES
MORPHOLOGY
PHASE STUDIES
POLYMERIZATION
X-RAY DIFFRACTION