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Updated: Jun 30, 2025
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Microfluidic Preparation of Liquid Crystalline Elastomer Actuators
Published on: May 20, 2018
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Elastocaloric Response of Isotropic Liquid Crystalline Elastomers.
Jeremy A Herman1, Jonathan D Hoang2, Timothy J White1,2
1Department of Chemical and Biological Engineering, University of Colorado, Jennie Smoly Caruthers Biotechnology Building, 3415 Colorado Ave, Boulder, CO, 80303, USA.
Small (Weinheim an Der Bergstrasse, Germany)
|March 20, 2024
Summary
New liquid crystalline elastomers (LCEs) show significant elastocaloric effects, achieving over ±3°C temperature changes with minimal force. This breakthrough offers potential for advanced solid-state cooling applications.
Area of Science:
- Materials Science
- Polymer Chemistry
- Thermodynamics
Background:
- Liquid crystalline elastomers (LCEs) link material order with deformation.
- The elastocaloric effect, a temperature change due to mechanical stress, is key for solid-state refrigerants.
- Previous LCE studies reported modest temperature changes (≈2°C) at high strains.
Purpose of the Study:
- To investigate the elastocaloric response of novel LCEs with subambient nematic-to-isotropic transition temperatures.
- To develop LCEs with enhanced elastic recovery and reduced hysteresis for improved refrigerant performance.
- To explore the relationship between deformation, order, and temperature change in these specialized LCEs.
Main Methods:
- Synthesizing LCEs using a two-step thiol-Michael/thiol-ene reaction for superior network properties.
- Characterizing the elastocaloric effect by measuring temperature changes during deformation and recovery cycles.
- Quantifying the force required for deformation and calculating responsivity.
Main Results:
- The synthesized LCEs demonstrated substantial elastocaloric temperature changes exceeding ±3°C (total ΔT of 6°C).
- Deformation was achieved with remarkably low forces (<<1 MPa).
- A high responsivity of 14°C MPa⁻¹ was recorded, seven times greater than natural rubber.
Conclusions:
- The developed
- isotropic
- LCEs exhibit significant elastocaloric effects at low applied forces.
- The enhanced network chemistry provides superior elastic recovery and reduced hysteresis.
- These LCEs represent a promising advancement for efficient solid-state cooling technologies.
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