选择反射波宽可电场调控的纳米聚苯胺/液晶复合材料的制备及性能研究

Chiral nematic (N*) liquid crystal (LC) materials with wide bandwidth of selectively reflecting circularly palarized incident light have sparked an enormous interest due to their potential for advanced applications, such as one-dimensional photonic crystals, brightness enhancement films of LC displays, energy-efficiency films of civil buildings and infrared-shielding films of military armaments. Thus, how to design and prepare the electrically controllable N*-LC films possesses important theoretical significance and practical value, which has already become a prevalent part of LC research. Herein, a series of nano-structured polyaniline(PANI) with different sizes, morphologies and properties will be prepared and dispersed in a N*-LC with a negative dielectric constant to prepare nano-structured PANI/N*-LC composites with good stability and electrically controllable bandwidth. Then, the interactions between the nano-structured PANI and the LC molecules, and the characteristics of the motion of nano-structured PANI in the N*-LC composites with an electric field applied will be explored in details. Furthermore, the mechanism of the effects of PANI on the electrically controllable bandwidth will be elucidated. Implementation of this project will provide experimental foundation and theoretical guidance for preparing the electrically controllable N*-LC films as well as expanding the applications of PANI in the field of LC materials.

具有宽波反射的手征性向列（N*）液晶材料在一维光子晶体、液晶显示器的光增亮膜、建筑节能薄膜、军事上的红外屏蔽和激光屏蔽等方面具有重要的应用前景。如何设计和制备电场可控的N*相液晶薄膜是液晶材料领域一个重要的研究方向，有着重要的理论意义和实用价值。本项目中我们将制备一系列性能、尺寸、形貌不同的导电聚苯胺（PANI）纳米材料，将其分散于各向介电常数为负性的N*相液晶中，制备具有性能稳定的选择反射波宽电场可控的纳米PANI/液晶复合材料。研究纳米PANI与液晶分子之间的相互作用规律，揭示在电场作用下PANI纳米材料在复合材料的N*相中的运动规律及对液晶反射特性的影响机理，为拓展宽波反射材料的设计方法和PANI纳米材料在液晶领域中的应用提供实验支持和理论指导。

本课题制备了一系列导电聚苯胺（PANI）纳米材料，研究了不同制备条件对PANI材料的微观形貌、导电性、机械力学性能、在手征性向列（N*）相液晶中的分散性等物理性能参数的影响规律。在此基础上制备了选择反射波宽电场可控的纳米PANI/液晶复合材料，并研究了PANI材料的形貌、尺寸对N*相液晶复合材料光学反射特性的影响规律，以及验证了此规律同样适用于不同长径比的一维硫化铋（Bi2S3）纳米材料/N*相液晶复合体系的光学反射性能变化，揭示了电场作用下纳米材料与N*相液晶分子相互作用的机理，为纳米材料在液晶领域中的应用提供实验数据和理论指导。此外，本课题还分别设计合成了手性偶氮化合物和手性螺烯化合物，研究了光响应手性化合物对N*相液晶光学反射特性的影响规律，为拓宽反射波带的设计方法奠定基础和提供新思路。