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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
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Isothermal Phase Transitions in Liquid Crystals Driven by Dynamic Covalent Chemistry
Daniel Martínez1, Tim Schlossarek2, Frank Würthner2
1Department of Chemistry, Universitat de les Illes Balears, Cra. Valldemossa, Km. 7.5, 07122, Palma de Mallorca, Spain.
Angewandte Chemie (International Ed. in English)
|April 18, 2024
Summary
Dynamic covalent chemistry enables isothermal phase transitions in calamitic liquid crystals. Researchers achieved transitions to crystal, isotropic, and smectic phases by reacting nematic arrays with various amines, creating adaptable liquid crystal systems.
Area of Science:
- Materials Science
- Organic Chemistry
- Supramolecular Chemistry
Background:
- Calamitic liquid crystals exhibit dynamic properties exploitable for phase transitions.
- Dynamic covalent chemistry offers a route to control material transformations.
- Isothermal phase transitions are desirable for energy-efficient material processing.
Purpose of the Study:
- To investigate isothermal phase transitions in liquid crystals driven by dynamic covalent chemistry.
- To explore the influence of amine structure on phase transformation outcomes.
- To design adaptable liquid crystal systems with tunable properties.
Main Methods:
- On-surface imination reactions between nematic liquid crystal arrays and various amines.
- Characterization using microscopy, spectroscopy, and X-ray techniques.
- Sequential imination and transimination processes to achieve controlled transformations.
Main Results:
- Achieved isothermal transitions from nematic to crystal, isotropic, and smectic phases.
- Demonstrated thermotropic liquid crystal behavior in the resulting materials.
- Successfully induced sequential phase transformations (nematic to smectic to nematic) via temperature control.
Conclusions:
- Dynamic covalent chemistry effectively drives isothermal phase transitions in liquid crystals.
- The choice of amine dictates the resulting phase and material properties.
- This research enables the design of programmable, adaptive liquid crystal materials.
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