Studies on photochemical control of macrostructure of polymers for automatic light and temperature modulators

1.合成了多种含手性基团的偶氮苯分子。通过对手性偶氮苯分子的掺杂，形成了胆甾型相。在紫外光和可见光的照射下，偶氮分子的扭转力发生改变，从而引起顺式光致异构化。结果表明，反式偶氮的扭转力大于顺式偶氮染料。利用诱导的胆甾相液晶实现了三种类型的开关。其一是选择性反思的转变。第二个是手性意义的反转，第三个是胆甾相和向列相之间的转换。聚合物与诱导的胆甾相液晶的复合也显示了光化学开关。此外，与不含聚合物的胆甾型材料相比，复合材料表现出更好的记忆性能。

1. Various azobenzene molecules (Azo) having chiral groups were prepared. Cholesteic phase was induced by doping the chiral azobenzene molecules. The twisting power of Azo molecules was changed by ultraviolet and visible light irradiation to cause trans-cis photoisomerization. The twisting power of trans-Azo was found to be larger than that of cis-Azo.2. Three types of switching was achieved by the use of the induced cholesteric liquid crystals. One is a shift of a selective reflection. Second is an inversion of the chiral sense, and third was a switching between the cholesteric phase and a nematic phase.3. Composite of polymer and the induced cholesteric liquid crystals was also found to / show the photochemical switchings. In addition, the composite materials showed good memory property more than the cholesteric materials without polymer.