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Updated: Jun 22, 2026
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Combining Microfluidics and Microrheology to Determine Rheological Properties of Soft Matter during Repeated Phase Transitions
Published on: April 19, 2018
Volume phase transitions of smectic gels
1Department of Bioscience and Bioinformatics, Faculty of Computer Science and System Engineering, Kyushu Institute of Technology, Kawazu 680-4, Iizuka, Fukuoka 820-8502, Japan. matuyama@bio.kyutech.ac.jp
Summary
This study introduces a mean-field theory for liquid crystal (LC) gel volume phase transitions, revealing discontinuous volume changes during isotropic-nematic and nematic-smectic-A phase shifts.
Area of Science:
- Materials Science
- Polymer Chemistry
- Soft Matter Physics
Background:
- Side-chain liquid crystalline (LC) gels exhibit complex phase behaviors.
- Understanding volume phase transitions in these gels is crucial for material design.
Purpose of the Study:
- To develop a mean-field theory for describing volume phase transitions in side-chain LC gels.
- To analyze phase transitions including isotropic-nematic and nematic-smectic-A transitions.
Main Methods:
- Utilized a mean-field theory approach.
- Defined multiple nematic (N1-N3) and smectic-A (S1-S3) phases using order parameters (Sm, Sb, sigma).
- Derived free energy for smectic-A phases in isotropic solvent and analyzed gel swelling, order parameters, and deformation versus temperature.
Main Results:
- The theory describes isotropic-nematic-smectic-A phase transitions.
- LC gels exhibit discontinuous volume changes at phase transition points.
- Key parameters include orientational order of mesogens and backbone, and translational order.
Conclusions:
- The developed mean-field theory accurately models volume phase transitions in side-chain LC gels.
- Discontinuous volume changes are characteristic of isotropic-nematic, isotropic-smectic-A, and nematic-smectic-A transitions in these gels.
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