光敏自组装多层膜用于向列型液晶光控取向的研究

Self-assembled Multilayers Films of Photopolymerizable Amphiphile Used as Nematic Liquid Crystals Photoalignment Layer

合成了含有光敏基团、双端为季铵阳离子的有机铵盐 .将这种季铵盐与聚乙烯基苯磺酸钠用 LBL(Layer-by-layer)方法组装成多层分子沉积膜 ,紫外光谱证明 ,这个过程为逐层、均匀沉积过程 .在偏振紫外光照射下 ,多层膜中和光矢量方向匹配的光敏基团发生 [2 +2 ]环加成反应 ,形成表面张力各向异性膜 .用该薄膜作向列相液晶的取向膜制成反平行液晶器件 ,在偏光显微镜下观察 ,发现取得均一、稳定的取向效果 .

A cationic bolaform amphiphile which had two double-bonds and could be polymerized by ultraviolet was synthesized. A layer-by-layer self-assembled film was prepared in aqueous solution by using this material and poly(sodium 4-styrenesulfonate). The UV-Vis spectra proved that the multilayers film was uniform. When polarized UV irradiated the film, the photosensitive double bond could be polymerized %via% [2+2] cycloaddition, and the production of reaction distributed along the polarized direction of incident UV. So that by this method an anisotropic film was prepared, we used this anisotropic film as alignment layer of nematic liquid crystals, and obtained a uniform and stable alignment result.