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60.0μm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。
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.