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Preparation of Monodomain Liquid Crystal Elastomers and Liquid Crystal Elastomer Nanocomposites
Published on: February 6, 2016
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Mixing twist-bend and ferroelectric nematic liquid crystals
Abinash Barthakur1, Bidisha Bag1, Santhegudda Jayaramappa Shivaraja1
1School of Physics, University of Hyderabad, Hyderabad 500046, India.
Physical Review. E
|March 16, 2024
Summary
Binary mixtures of liquid crystals CB9CB and RM734 show altered phase diagrams and physical properties. Small additions significantly impact transitions, stabilizing a wide nematic phase and altering director tilt fluctuations.
Area of Science:
- Materials Science
- Condensed Matter Physics
Background:
- Twist-bend (Ntb) and ferroelectric (NF) nematic liquid crystals display unique physical properties and phenomena.
- Understanding the behavior of binary mixtures is crucial for developing new liquid crystal applications.
Purpose of the Study:
- To investigate the phase diagram and physical properties of binary mixtures of CB9CB and RM734 mesogens.
- To analyze the impact of composition on phase transitions, director tilt fluctuations, spontaneous polarization, and elastic constants.
Main Methods:
- Experimental studies on binary mixtures of CB9CB and RM734.
- Analysis of phase transition temperatures and enthalpies.
- Temperature-dependent birefringence measurements.
- Spontaneous polarization and splay elastic constant measurements.
Main Results:
- N-Ntb and N-NF phase transition temperatures and enthalpies decrease with increasing mixture concentration, eventually disappearing to stabilize a wide nematic (N) phase.
- Strong director tilt fluctuations observed above the N-Ntb transition, with critical range and exponent consistent with mean-field theory.
- Spontaneous polarization of RM734 significantly decreases upon addition of CB9CB.
- Splay elastic constant temperature dependence in the N phase of mixtures differs from pristine components.
Conclusions:
- Even small amounts of one component in a binary mixture substantially alter the phase diagram and physical properties.
- The study provides insights into the tunability of liquid crystal phases and properties through mixing.
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