You Ra, Kang Sumin, Lee Changjae, Jeon Jisoo, Wie Jeong Jae, Kim Taek-Soo, Yoon Dong Ki
Department of Chemistry, KAIST, Daejeon 34141, Republic of Korea.
Department of Mechanical Engineering, KAIST, Daejeon 34141, Republic of Korea.
ACS Appl Mater Interfaces. 2021 Aug 4;13(30):36253-36261. doi: 10.1021/acsami.1c04999. Epub 2021 Jul 26.
The arrangement of mesogenic units determines mechanical response of the liquid crystal polymer network (LCN) film to heat. Here, we show an interesting approach to programming three-dimensional patterns of the LCN films with periodic topological defects generated by applying an electric field. The mechanical properties of three representative patterned LCN films were investigated in terms of the arrangement of mesogenic units through tensile testing. Remarkably, it was determined that LCN films showed enhanced toughness and ductility as defects increased in a given area, which is related to the elastic modulus mismatch that mitigates crack propagation. Our platform can also be used to modulate the frictional force of the patterned LCN films by varying the temperature, which can provide insight into the multiplex mechanical properties of LCN films.
介晶单元的排列决定了液晶聚合物网络（LCN）薄膜对热的机械响应。在此，我们展示了一种有趣的方法，通过施加电场产生周期性拓扑缺陷来对LCN薄膜的三维图案进行编程。通过拉伸测试，根据介晶单元的排列研究了三种代表性图案化LCN薄膜的机械性能。值得注意的是，已确定在给定区域内随着缺陷增加，LCN薄膜表现出增强的韧性和延展性，这与减轻裂纹扩展的弹性模量失配有关。我们的平台还可用于通过改变温度来调节图案化LCN薄膜的摩擦力，这可为深入了解LCN薄膜的多重机械性能提供依据。
