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Polydomain-monodomain orientational process in smectic-C main-chain liquid-crystalline elastomers
Antoni Sánchez-Ferrer1, Heino Finkelmann
1Food & Soft Materials Science Group, Institute of Food, Nutrition & Health, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland. antoni.sanchez@agrl.ethz.ch
Macromolecular Rapid Communications
|March 25, 2011
Summary
Stretching smectic-C liquid-crystalline elastomers transforms polydomain structures into a monodomain. This process, involving domain rearrangement, influences the material's stress-strain behavior.
Area of Science:
- Materials Science
- Polymer Physics
- Liquid Crystals
Background:
- Smectic-C main-chain liquid-crystalline elastomers (SmC MCLCEs) exhibit complex polydomain structures.
- Uniaxial stretching can induce a transformation from polydomain to monodomain states.
Purpose of the Study:
- To investigate the polydomain-monodomain (PM) transformation in SmC MCLCEs under uniaxial stretching.
- To quantify the domain rearrangement and orientational processes.
- To compare the mechanical response of polydomain and monodomain samples.
Main Methods:
- Combination of mechanical testing (stress-strain measurements).
- X-ray diffraction experiments to analyze domain structure and orientation.
Main Results:
- Observed domain rearrangement during stretching, leading to a perfect conical layer distribution (monodomain) in fully stretched samples.
- Quantified the rearrangement and orientational process.
- Demonstrated that the stress-strain behavior of the polydomain material lies between the parallel and perpendicular uniaxial deformations of the monodomain sample.
Conclusions:
- Uniaxial stretching effectively transforms polydomain SmC MCLCEs into monodomain structures.
- The PM transformation involves significant domain rearrangement and reorientation.
- The mechanical properties of polydomain elastomers are intermediate to those of monodomain elastomers under specific deformation conditions.
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