Title: Dual-Mode Patterns Enabled by Photofluidization of an Azobenzene-Containing Linear Liquid Crystal Copolymer

Author: Feng Pan, Yaoqing Feng, Yuyao Qian, Lang Qin*, Yanlei Yu*

Journal: Langmuir, 2024, 40, 22, 11766–11774

Abstract:

Creating dual-mode patterns in the same area of the material is an advanced method to increase the dimension of information storage, improve the level of encryption security, and promote the development of encoding technology. However, in situ, different patterns may lead to serious mutual interference in the process of manufacturing and usage. New materials and patterning techniques are essential for the advancement of noninterfering dual-mode patterns. Herein, noninterfering dual-mode patterns are demonstrated by combining the structural color and chromatic polarization, which is designed with an azobenzene-containing linear liquid crystal copolymer featuring a photofluidization effect. On the one hand, structural color patterns are imprinted via silicon templates with periodic microstructures after a UV-light-induced local transition of the polymer surface from a glassy to rubbery state. On the other hand, different polarization patterns based on the local photoinduced orientation of mesogens are created within the photofluidized region by the Weigert effect. Especially, the secondary imprinting is used to eliminate the partial damage to the structural color patterns during writing of the polarization patterns, thus obtaining dual-mode patterns without interference. This study provides a blueprint for the creation of advanced materials and sophisticated photopatterning techniques with potential cross-industry applications.

论文链接：https://pubs.acs.org/doi/10.1021/acs.langmuir.4c01297?ref=pdf

PDF下载：Dual-Mode Patterns Enabled by Photofluidization of an Azobenzene-Containing Linear Liquid Crystal Copolymer.pdf

信息存储和安全是全球广泛关注的话题。为了解决这一问题，研究人员开发了许多光学材料，如光子晶体、刺激响应材料和发光材料，用于验证钞票、贵重产品、重要文件等。图案化聚合物材料广泛应用于加密和信息存储，与单模式图案相比，双模式图案能够独立存储和读取，不仅增加了信息存储的维度，还提高了加密的安全水平。然而，在同一位置引入两种模式的图案可能会在制造和使用过程中导致强烈的相互干扰，因此独立存储和读取这些双模式图案是一个重大的挑战。本文利用偶氮苯线型液晶共聚物的光流体化特性构筑了无相互干扰的结构色与色偏振双模式图案，这两种图案能够独立写入与识别。所得双模式图案标签中的防伪结构具有分辨率高、经久耐用、可通过肉眼快速识别等特点，为多重防伪图案的构筑提供了新的途径。