As a promising actuating material, liquid crystal elastomer (LCE) has been intensively explored in building diverse active structures and devices. Recently, direct ink writing technique has been developed to print LCE structures with various geometries and actuation behaviors. Despite the advancement in printing LCE, it remains challenging to print three-dimensional (3D) LCE structures with graded properties. Here, we report a facile method to tailor both the actuation behavior and mechanical properties of printed LCE filaments by varying printing parameters. On the basis of the comprehensive processing-structure-property relationship, we propose a simple strategy to print functionally graded LCEs, which greatly increases the design space for creating active morphing structures. We further demonstrate mitigation of stress concentration near the interface between an actuatable LCE tube and a rigid glass plate through gradient printing. The strategy developed here will facilitate potential applications of LCEs in different fields.

作为有前途的驱动材料，液晶弹性体（LCE）已在构建各种有源结构和设备中进行了深入研究。近来，已经开发了直接墨水书写技术来打印具有各种几何形状和致动行为的LCE结构。尽管在打印LCE方面取得了进步，但是打印具有渐变属性的三维（3D）LCE结构仍然具有挑战性。在这里，我们报告了一种通过改变印刷参数来调整印刷的LCE细丝的致动行为和机械性能的简便方法。基于全面的处理-结构-属性关系，我们提出了一种简单的策略来打印功能分级的LCE，这大大增加了创建活动变形结构的设计空间。我们进一步证明了通过梯度印刷可以缓解LCE管和刚性玻璃板之间界面附近的应力集中。此处制定的策略将促进LCE在不同领域的潜在应用。