液晶与显示, 2012, 27 (6): 724, 网络出版: 2012-11-28  

温度梯度制备宽波反射液晶薄膜

Broadband Reflection Liquid Crystalline Film Prepared by Temperature Gradient
作者单位
1 北京科技大学 材料科学与工程学院, 北京100083
2 北京大学 工学院, 北京100871
摘要
合成了大螺旋扭曲力的手性化合物4,4′-2(戊基-环己基)苯甲酸异山梨醇酯(ISBB)。对60.0 μm厚ISBB/液晶性单体/向列相液晶/光引发剂复合体系的液晶层的上、下表面温度施加不同温度, 液晶层中形成了温度梯度。由于高温区域的液晶溶解ISBB的能力强, 低温区域的ISBB会向高温区域扩散, 从而在液晶薄层中形成了ISBB的浓度梯度与螺距梯度。紫外光聚合复合体系中的光可聚合单体, 单体间交联聚合形成网络固定住了液晶层内的螺距梯度, 从而制备出反射可见光波段的右旋圆偏振光的宽波反射液晶薄膜。
Abstract
The chiral dopant ISBB with large helical twist power was synthesized. Temperature gradient across the liquid crystal layer was formed by imposing different temperature on 60.0 μm ISBB/photo-polymerizable liquid crystalline monomer/nematic liquid crystal/photoinitiator composite layers upper and lower surfaces. Because high temperature region could dissolve more ISBB than low temperature region, ISBB would diffuse from low tempe-rature region to high temperature region, then ISBB concentration gradient and pitch gra-dient was formed across the composite layer. After irradiating the layer with ultraviolet light, crosslinking between the photo-polymerizable monomers occurred and the pitch gra-dient was fixed. Finally, a broadband reflection liquid crystalline film which could reflect light circularly polarized visible light was prepared.
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李克轩, 曹晖, 程紫辉, 张立培, 武晓娟, 杨槐, 沈卓身. 温度梯度制备宽波反射液晶薄膜[J]. 液晶与显示, 2012, 27(6): 724. LI Ke-xuan, CAO Hui, CHENG Zi-hui, ZHANG Li-pei, WU Xiao-juan, YANG Huai, SHEN Zhuo-shen. Broadband Reflection Liquid Crystalline Film Prepared by Temperature Gradient[J]. Chinese Journal of Liquid Crystals and Displays, 2012, 27(6): 724.

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