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Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
Liquid-crystalline polymer and block copolymer domain alignment controlled by free-surface segregation
Kei Fukuhara1, Yasuyoshi Fujii, Yuki Nagashima
1Department of Molecular Design and Engineering Graduate School of Engineering, Nagoya University, Chikusa, Nagoya, 464-8603, Japan.
Angewandte Chemie (International Ed. in English)
|April 26, 2013
Summary
A novel surface segregation method reorients liquid crystal (LC) mesogens and microphase separation (MPS) domains. This technique enables efficient in-plane photoalignment, offering new possibilities for LC material orientation control.
Area of Science:
- Materials Science
- Surface Chemistry
- Liquid Crystal Physics
Background:
- Controlling the orientation of liquid crystal (LC) mesogens and microphase separation (MPS) domains is crucial for advanced material applications.
- Existing methods for orientation control can be complex or limited in scope.
Purpose of the Study:
- To develop a simple and effective strategy for controlling the orientation of LC mesogens and MPS domains at a free surface.
- To enable efficient in-plane photoalignment of cylindrical domains within LC materials.
Main Methods:
- Utilizing a segregated skin layer at the free surface of the liquid crystal material.
- Investigating the orientational changes of mesogens and MPS domains induced by this surface modification.
Main Results:
- Achieved a transition in orientation from homeotropic to planar for both LC mesogens and MPS domains.
- Demonstrated efficient in-plane photoalignment of cylindrical domains facilitated by the surface segregation.
Conclusions:
- The surface segregation strategy provides a straightforward method for precise orientation control of LC materials.
- This approach is expected to broaden the applications of liquid crystals by enabling new orientation control possibilities.
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