Light-induced wrinkling in annulus anisotropic liquid crystal elastomer films

Area of Science:

• Materials Science
• Mechanical Engineering
• Soft Matter Physics

Background:

• Liquid crystal elastomer (LCE) films are promising for smart structures and flexible sensors due to their stimulus-responsive deformation.
• Wrinkling instability, caused by low out-of-plane stiffness, is a significant challenge for LCE film applications.

Purpose of the Study:

• To investigate light-induced wrinkling instability in annulus LCE films with an internal hole using an anisotropy constitutive model.
• To determine the critical conditions and wrinkle numbers for the onset of instability.

Main Methods:

• Utilized an anisotropy constitutive model for light-sensitive LCE films.
• Employed linear perturbation analysis to study wrinkling instability.
• Investigated the influence of anisotropic ratio, spontaneous strain ratio, light intensity, contraction coefficient, hole size, and film thickness.

Main Results:

• Anisotropic annulus LCE films exhibit a higher number of wrinkles upon instability compared to isotropic films.
• Phase diagrams illustrate the transition from flat to wrinkled states based on various parameters.
• Critical time for wrinkling onset decreases with increased light intensity and contraction coefficient.

Conclusions:

• Anisotropy significantly influences light-induced wrinkling instability in annulus LCE films.
• Controlling anisotropic parameters and geometric features allows for managing wrinkling behavior.
• Findings offer insights for designing advanced smart structures and flexible sensors using LCE films.