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Related Experiment Video

Updated: Sep 20, 2025

Microfluidic Preparation of Liquid Crystalline Elastomer Actuators

Microfluidic Preparation of Liquid Crystalline Elastomer Actuators

Published on: May 20, 2018

Halogen-Bonded Liquid Crystal Elastomers as Initiator-Free Photochemical Actuators.

Hongshuang Guo¹, Roshan Nasare¹, Chen Liang²

¹Smart Photonic Materials, Faculty of Engineering and Natural Sciences, Tampere University, P.O. Box 541, Tampere, FI-33101, Finland.

Advanced Materials (Deerfield Beach, Fla.)

|May 28, 2025

Summary

Researchers developed new liquid crystal elastomer (LCE) actuators using dynamic halogen bonds. This method achieves high molecular alignment and photoswitch content for advanced soft robotics and biomedical applications.

Keywords:

azobenzene halogen bonding liquid crystal elastomer photoactuation soft robotics

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Area of Science:

Materials Science
Polymer Chemistry
Supramolecular Chemistry

Background:

Liquid crystal elastomer (LCE) actuators need aligned photoswitchable molecules for effective light-driven actuation.
Achieving high molecular alignment and photoswitch concentration simultaneously, especially in thick LCEs, remains a significant challenge for advanced applications.

Purpose of the Study:

To develop a novel method for fabricating LCEs with high photoswitch content and excellent molecular alignment.
To create LCEs with multimodal actuation capabilities by combining dynamic halogen bonds and Aza-Michael addition polymerization.

Main Methods:

Utilized dynamic halogen bonds and Aza-Michael addition-based polymerization to synthesize azobenzene-containing LCEs.
Leveraged supramolecular interactions to eliminate the need for photo-initiators during LCE fabrication.
Achieved precise control over azobenzene content while maintaining high molecular alignment.

Main Results:

Developed LCEs exhibiting multimodal actuation, including light-guided rolling and underwater gripping.
Demonstrated the ability to control photoswitch content over a wide range without compromising molecular alignment.
Showcased the dynamic programming ability of the fabricated LCEs.

Conclusions:

The combination of dynamic halogen bonds and Aza-Michael addition polymerization offers a versatile route to advanced LCE actuators.
This approach overcomes previous limitations in achieving high molecular alignment and photoswitch content in LCEs.
The developed LCEs show significant potential for applications in soft robotics, biomedicine, and photonics.