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Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction
Published on: January 19, 2016
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Supramolecular Chalcogen-Bonded Shape Memory Actuators.
Hongshuang Guo1, J Mikko Rautiainen2, Hao Zeng1
1Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, Tampere, FI-33101, Finland.
Angewandte Chemie (International Ed. in English)
|May 20, 2025
Summary
Stronger chalcogen bonds (ChBs) in liquid crystal elastomers (LCEs) enable programmable shape memory and actuation. These materials can be used to create light-powered robots and temperature-responsive actuators.
Area of Science:
- Materials Science
- Supramolecular Chemistry
- Polymer Science
Background:
- Liquid crystal elastomers (LCEs) are advanced materials with unique responsive properties.
- Supramolecular chemistry offers pathways to engineer material characteristics through non-covalent interactions.
- Chalcogen bonds (ChBs) are a class of non-covalent interactions with tunable strengths.
Purpose of the Study:
- To synthesize and investigate supramolecular LCEs incorporating ChBs for shape memory and actuation.
- To explore the influence of ChB strength on the material's properties.
- To demonstrate the potential applications of these functionalized LCEs.
Main Methods:
- Synthesis of LCEs with varying ChB strengths (Se⋯N and S⋯N).
- Characterization of shape memory effects (SME) and actuation properties.
- Spectroscopic analysis (Solid-state NMR, Raman) and computational modeling (DFT) to understand ChB interactions.
Main Results:
- LCEs with strong Se⋯N ChBs (-40 to -43 kJ mol⁻¹) exhibited both SME and reversible actuation.
- LCEs with weaker S⋯N ChBs (-32 to -34 kJ mol⁻¹) did not show these properties.
- Se⋯N LCEs transitioned to two-way SME, enabling programmable 2D/3D shape transformations and rewritable patterns.
- Demonstrated applications include light-powered crawling robots and temperature-responsive actuators.
Conclusions:
- The strength and specificity of ChBs are critical for designing functional supramolecular LCEs.
- These findings pave the way for advanced supramolecular actuators and shape-morphing LCEs.
- The study provides molecular-level insights into ChB interactions within LCEs.
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