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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
From gas-liquid to liquid crystalline phase behavior via anisotropic attraction: a computer simulation study
Wen-Ze Ouyang1, Reinhard Hentschke
1Fachbereich Mathematik und Naturwissenschaften, Bergische Universität, D-42097 Wuppertal, Germany.
The Journal of Chemical Physics
|November 6, 2007
Summary
This study explores how self-assembling polymers transition from gas-liquid states to liquid crystals. This shift is driven by excluded volume interactions and tunable attractive forces between polymer chains.
Area of Science:
- Polymer Physics
- Soft Matter Physics
- Materials Science
Background:
- Self-assembling polymers exhibit complex phase behaviors.
- Understanding transitions between different phases is crucial for materials design.
- Equilibrium polymers can form reversible chains, influencing their macroscopic properties.
Purpose of the Study:
- To investigate the phase behavior of semiflexible equilibrium polymers using a continuum molecular model.
- To explore the transition from gas-liquid coexistence to liquid crystallinity.
- To understand the role of excluded volume interactions and anisotropic attractions in driving these phase transitions.
Main Methods:
- Utilized Monte Carlo simulations.
- Employed molecular dynamics simulations.
- Studied a continuum molecular model for self-assembling semiflexible equilibrium polymers.
Main Results:
- Observed a transfer from ordinary gas-liquid coexistence to liquid crystalline phases.
- Demonstrated that excluded volume interactions between rodlike aggregates drive this transition.
- Showed that a tunable anisotropic attractive interaction governs the transfer between phase behaviors.
Conclusions:
- Excluded volume interactions and anisotropic attractions are key factors in polymer self-assembly and phase transitions.
- The findings provide insights into controlling the formation of liquid crystalline phases in polymer systems.
- The study relates the behavior of these polymers to dipolar fluid models, highlighting similarities in reversible chain formation.
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