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Published on: January 19, 2016
Response of prestretched nematic elastomers to external fields.
A M Menzel1, H Pleiner, H R Brand
1Theoretische Physik III, Universität Bayreuth, 95440, Bayreuth, Germany. andreas.menzel@uni-bayreuth.de
The European Physical Journal. E, Soft Matter
|December 5, 2009
Summary
Prestretched liquid crystal elastomers show a reduced shear modulus during director rotation. External fields easily reorient the director in these specific regions, impacting material properties.
Area of Science:
- Materials Science
- Polymer Physics
- Soft Matter Physics
Background:
- Nematic side-chain liquid crystal elastomers exhibit unique anisotropic properties.
- Prestressing and external fields can induce significant changes in their director orientation and mechanical response.
Purpose of the Study:
- To investigate the mechanical and director reorientation behavior of prestretched nematic side-chain liquid crystal elastomers under combined external fields.
- To analyze the influence of prestretch orientation on the effective shear modulus and field-induced director rotation.
Main Methods:
- Utilizing conventional elasticity theory.
- Coupling elasticity theory with relative director-network rotations.
- Applying superimposed small-amplitude shear, electric, and magnetic fields.
Main Results:
- A strongly decreased effective shear modulus was observed near the onset and completion of enforced director rotation.
- External electric and magnetic fields were found to easily reorient the director in these specific regions.
- The orientation of prestretching perpendicular to the initial nematic director was crucial for enforcing director reorientation.
Conclusions:
- The interplay between prestretch, director orientation, and external fields significantly modifies the mechanical properties of liquid crystal elastomers.
- Understanding these responses is key for designing advanced soft materials with tunable properties.
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