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Complex liquid-crystal nanostructures in semiflexible ABC linear triblock copolymers: A self-consistent field theory
Shiben Li1, Ying Jiang2, Jeff Z Y Chen3
1Department of Physics, Wenzhou University, Wenzhou, Zhejiang 325035, China.
The Journal of Chemical Physics
|November 17, 2016
Summary
Researchers found that adjusting the flexibility of semiflexible polymer chains in ABC triblock copolymers allows for control over their microphase-separated structures. This offers a new way to design advanced polymer materials.
Area of Science:
- Polymer Science
- Materials Science
- Soft Matter Physics
Background:
- Block copolymers self-assemble into ordered nanostructures.
- Semiflexible polymers exhibit unique chain conformations and ordering behaviors.
- Understanding phase transitions is crucial for materials design.
Purpose of the Study:
- To investigate order-to-order phase transitions in ABC linear triblock copolymers.
- To analyze the impact of middle block flexibility on microphase separation.
- To explore the role of liquid-crystal ordering in these systems.
Main Methods:
- Utilized a theoretical framework based on self-consistent field (SCF) theory.
- Employed the wormlike-chain model to describe polymer chains.
- Incorporated Flory-Huggins and Maier-Saupe interactions into the free energy calculations.
Main Results:
- Identified sequences of order-to-order phase transitions as flexibility varies.
- Observed various spatial and orientational symmetries in microphase-separated states.
- Some phases exhibited liquid-crystal ordering, analyzed against experimental and theoretical data.
Conclusions:
- Tuning the flexibility parameter of semiflexible B-blocks is a viable strategy for designing microphase-separated structures.
- This approach offers control over nanostructure formation in copolymer melts.
- The findings provide a pathway for creating novel materials with tailored properties.
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