光响应性偶氮聚电解质自组装研究

将3种侧链带有不同偶氮生色团的聚电解质,用逐层浸渍的方法使其组装成多层膜.利用原子力显微镜(AFM)研究了自组装膜的表面形貌以及随着组装层数增加的变化.详细研究了在紫外光的照射下,薄膜内偶氮生色团由反式到顺式构型的光响应转变,以及在暗室中由顺式回复到反式构型的回复特性.与自组装膜的光响应性和相应的旋涂膜进行比较发现,其中的PNAPE/PDAC自组装膜没有明显的光色效应,而PEAPE/PDAC,PPAPE/PDAC具有明显的光色效应.在暗室中,随生色团的结构不同和在不同的凝集态中,由顺式回复到反式构型的速率明显不同.

Self-assembly of Photo-responsive Azo Polyelectrolytes

Three azo polyelectrolytes were successfully fabricated into self-assembled multilayers through a layer-by-layer dipping technique. The surface morphology and its variation with the bilayer growth were investigated with atomic force microscopy(AFM). Thecis-trans isomerization of the self-assembled thin films was studied with UV-Vis spectroscopy and compared with the spin-coated films. PEAPE/PDAC and PPAPE/PDAC multilayers show significant photochromic effect upon UV light irradiation. In dark condition, the rates ofcis-to-trans isomerization depend on the chromophore structure. For polyelectrolytes containing the same chromophores, the azo dyes in self-assembled multilayer recover much faster fromcis totrans isomer than those in spin-coated films.