Color Modulation in Morpho Butterfly Wings Using Liquid Crystalline Elastomers

Abstract

Nature provides well‐engineered and evolutionary optimized examples of brilliant structural colors in animals and plants. Morpho butterflies are among the well‐known species possessing iridescent bright blue coloration due to multiple optical effects generated by the complex structuration of the wing scales. Such surprising solution can be replicated to fabricate efficient devices. Maybe even more interesting, novel approaches can be developed to combine wings with synthetic smart materials to achieve complex structures responsive to external stimuli. This study demonstrates the proof of concept of an innovative biotic–abiotic hybrid smart structure made by the integration of a butterfly wing with thermoresponsive liquid crystalline elastomers, and their capability to actuate the mechanical action of the wing, thus controlling its spectral response. Exploiting two fabrication strategies, it is demonstrated how different mechanisms of color tuning can be achieved by temperature control. In addition, due to the thermally induced mechanical deformation of the elastomer and superhydrophobic properties of the wing, a potential self‐cleaning behavior of the bilayer material is demonstrated.

Large-Size Honeycomb-Shaped and Iris-Like Liquid Crystal Elastomer Actuators

“…Finally, the aligned LC mixture was locked down in the "monodomain" nematic state by a thiol-ene/acrylate photopolymerization. [43][44][45] Figures 2a and 2b and Supporting Information Figures S4a and S4b show the final honeycomb-shaped LCEs with two fused hexagonal lattices and one hexagonal lattice peeled off the PDMS mold. The dimensions of the final honeycomb-shaped LCEs were slightly smaller than those of the initial mold [e.g., 1.8 mm (side) × 1.8 mm (height) × 0.5 mm (wall thickness) instead of 2 mm (side) × 2 mm (height) × 0.5 mm (wall thickness)] (Figures 2a and 2b).…”

Effects of Measurement Configurations on the Sensitivity of Morpho Butterfly Scales Based Chemical Biosensor

“…Where ε 0 and μ 0 are permittivity and permeability in free space. By substituting (2-8), (2-9) into (2-10), (2)(3)(4)(5)(6)(7)(8)(9)(10)(11) and eliminating E l,gz and H l,gz (the Z components of E l,g and H l,g ), and applying the inverse rule [25], the coupled-wave equations under TE mode can be obtained:…”

“…Then the S l,i (z) and U l,i (z) can be obtained by solving the coupled-wave equations (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12) and (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13).…”

“…In recent years, the Morpho butterfly wings are widely studied for their selective absorption and reflection of electromagnetic waves with different wavelengths [1][2][3][4][5][6]. The structural color-Morpho blue is the main color of the Morpho butterfly wing in connection with various optical phenomena such as scattering, interference, and diffraction [7,8].…”

Plasma‐Induced Polymerizations: A New Synthetic Entry in Liquid Crystal Elastomer Actuators

“…In contrast, when the plasma power increased to 150 and 200 W, the gel content of the final sample was 69% and 71%, respectively, which was similar to gel contents of the LCEs prepared by UV polymerization for 30 min (73%). [ 52 ] The relatively low gel content of this system was caused by the stoichiometric excess of allyl groups from both C4 and RM82 in the formulations (C4:EDDET:RM82 = 1:1:0.4). RM82 participated in the elastomer as monomer and cross‐linker, which might lead to unreacted allyl groups.…”