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Updated: Aug 11, 2026
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Preparation of Monodomain Liquid Crystal Elastomers and Liquid Crystal Elastomer Nanocomposites
Published on: February 6, 2016
Highly ordered monodomain ionic self-assembled liquid-crystalline materials
Y Zakrevskyy1, B Smarsly, J Stumpe
1Fraunhofer Institute for Applied Polymer Research, Science Campus Golm, Geiselbergstrasse 69, D-14476 Potsdam, Germany.
Summary
The ionic self-assembled complex, benzenehexacarboxylic- (didodecyltrimethylammonium)6 [BHC- (C12D)6], forms a bilayer smectic liquid-crystalline phase. Ionic interactions influence its properties, enabling crystallization from the liquid crystal phase.
Area of Science:
- Materials Science
- Supramolecular Chemistry
- Physical Chemistry
Background:
- Ionic self-assembly is a key strategy for creating complex molecular architectures.
- Liquid-crystalline phases offer unique optical and structural properties for advanced materials.
Purpose of the Study:
- To investigate the liquid-crystalline properties of the benzenehexacarboxylic- (didodecyltrimethylammonium)6 [BHC- (C12D)6] complex.
- To understand the influence of ionic interactions on the self-assembled structure and phase behavior.
Main Methods:
- Polarizing microscopy
- Differential scanning calorimetry (DSC)
- X-ray analysis
- Null ellipsometry
- UV and IR spectroscopy
Main Results:
- The complex exhibits a spontaneous aligning bilayer smectic Sm-A2 liquid-crystalline phase.
- X-ray analysis revealed a lamellar structure with d-spacing of 3.15 nm, comprising two distinct sublayers.
- Ionic interactions were found to significantly impact the material's dynamics, allowing crystallization from the liquid crystal phase.
Conclusions:
- The [BHC- (C12D)6] complex forms an aligned Sm-A2 liquid-crystalline phase with structural characteristics determined by ionic interactions.
- The observed self-alignment and crystallization behavior are directly linked to the strong ionic forces within the complex.
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