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Elastic Characterization of Acrylate-Based Liquid Crystal Elastomers
Gevorg S Gevorgyan1, Maksim L Sargsyan1, Mariam R Hakobyan1
1Institute of Physics, Yerevan State University, Yerevan 0025, Armenia.
Polymers
|March 13, 2025
Summary
This study fully characterized acrylate-based liquid crystal elastomers (LCEs), determining their five elasticity coefficients. The findings provide crucial data for designing LCEs in emerging technologies.
Area of Science:
- Materials Science
- Polymer Science
- Soft Matter Physics
Background:
- Liquid crystal elastomers (LCEs) exhibit reversible changes in shape and optical properties in response to stimuli.
- Their unique characteristics make them suitable for advanced technological applications.
- Understanding the mechanical properties of LCEs is vital for studying their deformation behaviors and for device integration.
Purpose of the Study:
- To conduct a comprehensive elastic characterization of acrylate-based LCE materials.
- To determine the five elasticity coefficients governing the elastic-free energy density of these LCEs.
- To measure Young's moduli and Poisson ratios for these advanced materials.
Main Methods:
- Fabrication of highly aligned macroscopic samples of acrylate-based LCEs.
- Performing three tensile experiments to measure material response.
- Correlating measured strains with elasticity coefficients to determine material properties.
Main Results:
- Determined the five elasticity coefficients for acrylate-based LCEs for the first time.
- Measured Young's moduli on the order of MPa with an anisotropy ratio (E‖/E⟂) of approximately 4.5.
- Observed longitudinal Poisson ratios close to 0.5, indicating a uniaxial elastic response at low strains.
Conclusions:
- The experimental elastic characterization aligns well with theoretical predictions for LCEs.
- This work provides essential data for the efficient design and application of acrylate-based LCEs.
- The auxetic behavior above a strain threshold highlights the complex mechanical response of these materials.
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