高Δn低粘度液晶的合成及性能研究

利用二苯乙炔为中心基团上的核心结构,合成了多种极性较低的液晶和几种含氟液晶单体化合物,并按10%的质量分数与商用液晶进行了混配,同时制成了平行排列的液晶盒.通过旋转粘度计分别测量了混合后的液晶溶液的粘度.利用光谱型椭偏仪测量了633 nm下的平行液晶盒的Δn,并且外推出了掺入的液晶单体的Δn,其结果与Vuks方程的计算结果吻合得很好.结果显示,二苯乙炔类液晶比传统的联苯类液晶的Δn有了显著提高,同时保持了相对较低的粘度,适合用于要求具有快速响应特性的液晶器件.

Synthesis and Properties of High Birefringence and Low Viscosity Liquid Crystal

A group of liquid crystal (LC) single compounds with low polar or fluorine substitutes, which employee tolane as their mesogenic core, were synthesized and mixed with commercial liquid crystal mixture (10% by weight). Then, parallel-aligned liquid crystal cells were made with these mixtures. The viscosities of these mixtures were measured by rotational viscometer respectively. And the birefringence (Δn) of these LC cells were measured by spectroscopic ellipsometer at 633 nm. The Δn of each LC single compound was extrapolated, the results show a reasonable correlation with that calculated by Vuks equation. These tolane-type liquid crystals have remarkable higher Δn than the biphenyl compounds, and relative low viscosity, so should be suitable for the applications that require high speed response.