Functional properties as amphiphiles of novel nanomolecular material, dendrimer

树枝状大分子由核心、重复单元和功能末端组成，有望成为具有复杂功能的材料。新的功能也产生于树枝状大分子的组织。本工作合成了具有疏水(正己基)端基和亲水性(羟基、糖苷或胺)端基的两亲树枝状大分子，并考察了分子在固-液(水)界面的组装情况。具有正己基/胺端基的树状大分子的组装能力略低于具有正己基/羟基端基的树枝状大分子，但其组装能力优于具有正己基/糖苷端基的树状大分子。自组装单分子膜是一种有组织的分子组装。由于我们已经发现羧酸衍生物可以构建自组装单分子膜和硫醇衍生物，因此我们研究了由末端带有羧酸的树枝状大分子制备单分子膜的方法。树枝状大分子在金属基片上的吸附效果要好于含胺基端的吸附。结果表明，吸附过量依赖于pH，但自组装单分子膜即使在用水冲洗后也不会从衬底上解吸。证实了单分子膜的形成是由于羧酸与金属基质的相互作用所致。

Dendrimers, which consist of a core, repeating units, and functional terminals, are expected as materials with complex functionalities. The novel functionality also generates from the organization of dendrimers. In the present work, amphiphilic dendrimers with hydrophobic (n-hexyl) terminals and hydrophilic (hydroxyl, glycoside, or amine) terminals were synthesized, and the molecular assemblies at the solid-liquid (water) interface were examined. A dendrimer with n-hexyl/amine terminals displayed slightly less ability of assembly formation than a dendrimer with n-hexyl/hydroxyl terminals, but the ability was superior to that of a dendrimer with n-hexyl/glycoside terminals.Self-assembled monolayer is one of organized molecular assemblies. Since we have found that carboxylic acid derivatives construct self-assembled monolayers as well as thiol derivatives, the monolayer preparation from a dendrimer with carboxylic acid terminals was examined. The dendrimer adsorbed more preferably on metal substrate than that with amine terminals. The excess adsorption depending on pH was observed, but the self-assembled monolayer does bot desorb from the substrate even after the rinse by water. It was confirmed that the monolayer formation proceeds owing to the interaction of carboxylic acid with metal substrate.