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Synthesis of Programmable Main-chain Liquid-crystalline Elastomers Using a Two-stage Thiol-acrylate Reaction
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Enhancing Thermo-Mechanical Properties of Liquid Crystal Elastomers through Chain Entanglements
Devyansh Agrawal1, Gaoweiang Dong2, Shengqiang Cai1,2
1Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, California 92093, United States.
ACS Applied Materials & Interfaces
|May 7, 2025
Summary
Mechanical kneading enhances liquid crystal elastomers (LCEs) by creating chain entanglements. This improves thermo-mechanical performance, actuation, and enables fabrication of monodomain LCEs for advanced applications.
Area of Science:
- Materials Science
- Polymer Chemistry
- Soft Matter Physics
Background:
- Liquid crystal elastomers (LCEs) are stimuli-responsive materials with potential in actuators.
- Current LCEs face limitations in thermo-mechanical performance and fabrication complexity.
Purpose of the Study:
- To enhance the thermo-mechanical performance and actuation capabilities of LCEs.
- To develop a method for fabricating monodomain LCEs.
Main Methods:
- Inducing chain entanglements in LCEs via mechanical kneading.
- Characterizing the thermo-mechanical properties and actuation performance of the modified LCEs.
- Utilizing chain entanglements for the synthesis of aligned LCEs.
Main Results:
- Mechanical kneading significantly improved LCE mechanical properties across various strain rates and temperatures.
- Enhanced actuation performance, including higher stresses, greater contraction, and improved high-temperature stability.
- Chain entanglements facilitated the fabrication of monodomain LCEs.
Conclusions:
- Chain entanglements are a key factor in improving LCE performance.
- Mechanical kneading offers a viable strategy for designing high-performance LCE actuators.
- This approach provides a pathway for advanced LCE applications.
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