Dynamical Landau-de Gennes theory for electrically-responsive liquid crystal networks

Area of Science:

• Materials Science
• Soft Matter Physics
• Polymer Science

Background:

• Liquid crystal networks integrate liquid crystal order with polymer elasticity for responsive coatings.
• Recent experiments demonstrated reversible surface modulation of these networks using AC electric fields.

Purpose of the Study:

• To develop a Landau-type theory for electrically responsive liquid crystal networks.
• To explain experimental findings and guide rational design strategies for responsive coatings.
• To investigate the influence of material parameters on network dynamics and deformation.

Main Methods:

• Construction of a Landau-type theoretical model.
• Molecular dynamics simulations to analyze network behavior.
• Comparison of theoretical predictions with experimental results.

Main Results:

• The theory qualitatively agrees with simulations and reproduces key experimental features.
• Nematogen aspect ratio, initial orientational order, and cross-linking fraction affect plasticization time.
• Dynamic response to oscillating electric fields exhibits two resonances tunable by material parameters.

Conclusions:

• The developed theory provides a framework for understanding and designing electrically responsive liquid crystal networks.
• Material parameters offer experimental control over the plasticization time and dynamic response of coatings.
• This work facilitates the development of advanced responsive coatings for various applications.