3D‐Printed Biomimetic Structural Colors

• Published in: Small (Weinheim an der Bergstrasse, Germany) Vol. 20; no. 5; pp. e2306646 - n/a
• Main Authors: Bi, Ran, Li, Xiaohong, Ou, Xingcheng, Huang, Jiaqi, Huang, Dantong, Chen, Guoliang, Sheng, Yu, Hong, Wei, Wang, Yan, Hu, Weijie, Guo, Shuang‐Zhuang
• Format: Journal Article
• Language: English
• Published: Germany Wiley Subscription Services, Inc 01.02.2024
• Subjects: Biomimetics; bionic robots; Bionics; Cholesteric liquid crystals; Color; direct‐ink‐writing; Elastomers; Locomotion; Rheological properties; Shear flow; Solvents; solvent‐cast; structural color; Three dimensional printing; direct-ink-writing; cholesteric liquid crystals; solvent-cast; structural color; bionic robots
• ISSN: 1613-6810; 1613-6829
• DOI: 10.1002/smll.202306646

Resolution control and expansibility have always been challenges to the fabrication of structural color materials. Here, a facile strategy to print cholesteric liquid crystal elastomers (CLCEs) into complex structural color patterns with variable resolution and enhanced expansibility is reported. A volatile solvent is introduced into the synthesized CLC oligomers, modifying its rheological properties and allowing direct‐ink‐writing (DIW) under mild conditions. The combination of printing shear flow and anisotropic deswelling of ink drives the CLC molecules into an ordered cholesteric arrangement. The authors meticulously investigate the influence of printing parameters to achieve resolution control over a wide range, allowing for the printing of multi‐sized 1D or 2D patterns with constant quality. Furthermore, such solvent‐cast direct‐ink‐writing (DIW) strategy is highly expandable and can be integrated easily into the DIW of bionic robots. Multi‐responsive bionic butterfly and flower are printed with biomimetic in both locomotion and coloration. Such designs dramatically reduced the processing difficulty of precise full‐color printing and expanded the capability of structural color materials to collaborate with other systems. A novel approach for producing cholesteric liquid crystal elastomers with vibrant structural colors using solvent‐cast direct‐ink‐writing is presented. By leveraging this scalable and versatile technique, the ability to create complex and intricate patterns, as well as bionic robots such as a butterfly and a flower, which are responsive to magnetic fields and thermal stimuli is demonstrated.