中文摘要：

胆酸是罕见的天然面式双亲性分子,在体内或体外能自组装形成胶束或超分子结构,包裹脂溶性或水溶性物质,合成的含胆酸低聚物和高分子仍保留了胆酸的特性,受此启发,设计并构建了胆酸高分子刷修饰的表面,考察了胆酸高分子刷在材料表面的溶剂响应特性及其选择吸附能力.通过化学法将胆酸固定到聚甲基丙烯酸羟乙酯高分子刷接枝修饰的聚丙烯微滤膜表面,采用水接触角测量法,用荧光光谱和荧光显微镜等对胆酸高分子刷修饰的表面进行表征.结果表明,胆酸高分子刷修饰表面的水接触角随溶剂极性的改变而变化,表面具有溶剂响应性.同时,表面固定的胆酸高分子刷随着溶剂极性的改变形成了相应的疏水或亲水微区,具有溶剂响应的选择吸附能力.

英文摘要：

Cholic acid possesses a special facial amphiphilic structure with unusual distribution of hydrophobic and hydrophilic regions.Accordingly,these biological molecules can self-assemble to form micelles and different superstructures in vivo and vitro,which could package liposoluble and water soluble substances separately.The properties are retained in the synthetic oligomer and polymers containing cholic acid.Inspired by the facial amphiphilicity and self-assembly properties of cholic acid,cholic acid-containing polymer brushes were used to modify the surface properties of the materials.The abilities of solvent-responsiveness and selective adsorption of the modified surface were studied.In this work,cholic acids were chemically bound to the polymer brushes of poly hydroxyethyl methacrylate（poly HEMA）on the microporous polypropylene membranes.The cholic acid-containing polymer brushes modified membrane surfaces were characterized by water contact angle measurement,fluorescence spectrometry and fluorescence microscopy.The results demonstrate the static water contact angle of the colic acid modified surface changes with the polarity of the solvent used for pretreating the surface,which means that the surface is solvent-responsive.Meanwhile,the conformations of cholic acid-containing polymer brushes on the surface change considerably with the polarity of solvent,which forms hydrophobic or hydrophilic domains.The adsorption of pyrene on the modified surface shows the solvent-responsive ability of cholic acid-containing polymer brushes.