环状光敏手性剂不仅具有较好的光稳定性, 且可以通过控制环张力而对分子的光异构化速率进行调控, 但其与液晶分子间的相容性有待提高。本文通过在联萘基团的6,6′位点处引入与液晶分子结构相似的棒状刚性取代基, 制备了BPO5BA联萘偶氮苯环状光敏手性剂, 探究了其在溶液和液晶中的光异构化过程, 并通过计算Teas溶解度参数对手性剂分子与液晶分子间的相容性进行探究。通过研究发现, 与Azo-o-Bi分子相比, BPO5BA分子中由于刚性取代基的引入, 使偶氮苯基团的转动受到了环张力和刚性的限制, 导致该分子在溶剂和液晶中的光异构化程度较低。此外, BPO5BA分子具有与Azo-o-Bi分子相反螺旋方向和较大的β值, 且与液晶分子间的相容性较好。

The cyclic photosensitive chiral dopant has not only better photostability, but also the photoisomerization rate of the molecule, which can be regulated by controlling the ring tension. However, the compatibility between the cyclic molecule and CLCs needs to be improved. In this paper, naphthalene azobenzene cyclic photosensitive chiral dopant BPO5BA was prepared by introducing rod-like rigid substituents at the 6,6’ positions of the naphthalene group, which were similar to the molecular structure of the liquid crystal. The photoisomerization processes in solution and CLCs were investigated, as well as the compatibility between BPO5BA molecule and CLCs was estimated by calculating Teas parameters. Compared with Azo-o-Bi molecule, the rotation of azobenzene group in BPO5BA is limited by the ring tension and rigidity, due to the introduction of rigid group, resulting in a low degree of photoisomerization. In addition, BPO5BA molecule has an opposite helical direction and larger β value, and has good compatibility with CLCs.