Wang Tingting, Zhao Jinghua, Wu Limin, Liu Wei, Li Yi, Yang Yonggang
State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, P. R. China.
School of Environmental Science and Engineering, Yancheng Institute of Technology, Yancheng, Jiangsu 224051, P. R. China.
ACS Appl Mater Interfaces. 2023 Sep 20;15(37):44314-44321. doi: 10.1021/acsami.3c09576. Epub 2023 Sep 7.
Composite colors have been widely found in nature. Herein, polymer-stabilized cholesteric liquid crystal (PSCLC) films with composite structural colors were prepared through a one-step photopolymerization approach. The CLC mixtures were prepared using a mixture of acrylates and a mixture of two chiral dopants. One of the chiral dopants is polymerizable, and the other one is photoisomerizable. After photopolymerization, the PSCLC films with double Bragg reflection bands were obtained on the surface of a substrate. The competition between the photopolymerization of the acrylates and the photoisomerization of the chiral dopant was proposed to drive the formation of the double reflection bands. Without oxygen inhibition, the polymerization of the acrylates near the substrate surface was carried out. However, due to oxygen inhibition, the polymerization of the acrylates near the air was retarded. Then, the photoisomerization of the chiral dopant was carried out prior to the polymerization of the acrylates. The wavelengths of the double reflection bands were tunable by changing the concentrations of the acrylates and chiral dopants and the polymerization temperature. Colorful patterns with composite structural colors were prepared, which were suitable for decoration and anti-counterfeiting.
复合颜色在自然界中广泛存在。在此，通过一步光聚合方法制备了具有复合结构颜色的聚合物稳定胆甾相液晶（PSCLC）薄膜。胆甾相液晶混合物是使用丙烯酸酯混合物和两种手性掺杂剂的混合物制备的。其中一种手性掺杂剂是可聚合的，另一种是可光异构化的。光聚合后，在基板表面获得了具有双布拉格反射带的PSCLC薄膜。提出丙烯酸酯的光聚合与手性掺杂剂的光异构化之间的竞争驱动了双反射带的形成。在没有氧抑制的情况下，进行了基板表面附近丙烯酸酯的聚合。然而，由于氧抑制，空气附近丙烯酸酯的聚合受到阻碍。然后，在手性掺杂剂的光异构化之后进行丙烯酸酯的聚合。通过改变丙烯酸酯和手性掺杂剂的浓度以及聚合温度，可以调节双反射带的波长。制备了具有复合结构颜色的彩色图案，适用于装饰和防伪。
