Jiang Huan, Chung Christopher, Dunn Martin L, Yu Kai
Department of Mechanical Engineering, University of Colorado Denver, Denver, CO, 80217, USA.
Nat Commun. 2024 Oct 1;15(1):8491. doi: 10.1038/s41467-024-52716-5.
Multifunctional composites have been continuously developed for a myriad of applications with remarkable adaptability to external stimuli and dynamic responsiveness. This study introduces a 4D printing method for liquid crystal elastomer (LCE) composites with continuous fibers and unveils their multifunctional actuation and exciting mechanical responses. During the printing process, the relative motion between the continuous fiber and LCE resin generates shear force to align mesogens and enable the monodomain state of the matrix materials. The printed composite lamina exhibits reversible folding deformations that are programmable by controlling printing parameters. With the incorporation of fiber reinforcement, the LCE composites not only demonstrate high actuation forces but also improved energy absorption and protection capabilities. Diverse shape-changing configurations of 4D composite structures can be achieved by tuning the printing pathway. Moreover, the incorporation of conductive fibers into the LCE matrix enables electrically induced shape morphing in the printed composites. Overall, this cost-effective 4D printing method is poised to serve as an accessible and influential approach when designing diverse applications of LCE composites, particularly in the realms of soft robotics, wearable electronics, artificial muscles, and beyond.
多功能复合材料不断发展，适用于众多应用，对外部刺激具有显著的适应性和动态响应能力。本研究介绍了一种用于含连续纤维的液晶弹性体（LCE）复合材料的4D打印方法，并揭示了其多功能驱动和令人兴奋的机械响应。在打印过程中，连续纤维与LCE树脂之间的相对运动会产生剪切力，使介晶排列并使基体材料处于单畴状态。打印的复合层板表现出可逆的折叠变形，可通过控制打印参数进行编程。通过加入纤维增强材料，LCE复合材料不仅表现出高驱动力，还提高了能量吸收和保护能力。通过调整打印路径，可以实现4D复合结构的多种形状变化配置。此外，将导电纤维加入LCE基体中可使打印复合材料实现电致形状变形。总体而言，这种经济高效的4D打印方法有望成为设计LCE复合材料各种应用时一种易于使用且有影响力的方法，特别是在软机器人技术、可穿戴电子设备、人造肌肉等领域。
