Design and Characterization of Deformable Superstructures Based on Amine-Acrylate Liquid Crystal Elastomers

Area of Science:

• Materials Science
• Polymer Chemistry
• Mechanical Engineering

Background:

• Deformable superstructures offer superior large deformation properties compared to natural materials.
• Conventional substrates limit the application scope of deformable superstructures in advanced fields like robotics and aerospace.
• Liquid Crystal Elastomers (LCEs) present a promising alternative substrate material due to their unique properties.

Purpose of the Study:

• To utilize amine-acrylate-based LCEs as substrates for deformable superstructures, enhancing driving stress and strain capabilities.
• To investigate the influence of varying amine-to-acrylate molar ratios on LCE thermal and mechanical properties.
• To develop and validate a novel LCE-based superstructure with a negative Poisson's ratio for reconfigurable applications.

Main Methods:

• Synthesis and characterization of amine-acrylate-based liquid crystal elastomers (LCEs) with varying molar ratios.
• Development of an anisotropic finite deformation model for LCEs based on hyperelastic theory to predict temperature-induced changes.
• Fabrication of an LCE-based paper-cutting structure with a negative Poisson's ratio and a 2D lattice superstructure using laser cutting.
• Experimental analysis and finite element method (FEM) simulations to study the deformation processes of the developed superstructure.

Main Results:

• LCEs with an amine-to-acrylate molar ratio of 0.9 demonstrated optimized polymerization degree, elongation at break, and toughness.
• The developed anisotropic finite deformation model accurately captured the configuration variations of LCEs under thermal activation.
• The fabricated LCE-based superstructure exhibited pre-programmed deformability and a negative Poisson's ratio, validated by experimental and FEM results.

Conclusions:

• Amine-acrylate-based LCEs serve as effective substrates for high-performance deformable superstructures, offering tunable thermal and mechanical properties.
• The developed LCE-based superstructure with a negative Poisson's ratio demonstrates significant potential for advanced reconfigurable systems.
• This research paves the way for enhanced applications of deformable superstructures and LCEs in defense, aerospace, and bionic robotics.