Ikkala Olli, ten Brinke Gerrit
Department of Engineering Physics and Mathematics, and Center for New Materials, Helsinki University of Technology, P.O. Box 2200, FIN-02015 HUT, Espoo, Finland.
Chem Commun (Camb). 2004 Oct 7(19):2131-7. doi: 10.1039/b403983a. Epub 2004 Sep 16.
Combination of self-assembly at different length scales leads to structural hierarchies. It offers rich possibilities to construct nanostructured matter, nanoscale parts, and switching (responsive) properties based on the phase transitions of the self-assembled structures. Complexation of oligomeric amphiphiles to polymers using ionic interactions, coordination, or hydrogen bonding leads to polymeric comb-shaped supramolecules (complexes), which self-assemble at a length scale of a few nm. Self-assembly at an order of magnitude larger length scale is provided by block copolymers, and combination of the latter two concepts leads to structural hierarchies. They provide e.g. templates for mesoporous materials and nano-objects, and allow switching conductivity and switching optical properties. Structural hierarchies are also observed by complexing moderately monodisperse polymeric rods with amphiphiles. Finally, self-assembly at even a larger length scale upon using colloidal particles may be combined to the above structures, as encouraged by recent observations.
不同长度尺度下的自组装相结合会导致结构层次的形成。这为构建纳米结构物质、纳米级部件以及基于自组装结构相变的开关（响应）特性提供了丰富的可能性。利用离子相互作用、配位或氢键作用使低聚两亲物与聚合物复合，会形成聚合物梳状超分子（复合物），其在几纳米的长度尺度上进行自组装。嵌段共聚物提供了一个数量级更大长度尺度的自组装，而后两种概念的结合会导致结构层次的形成。它们例如为介孔材料和纳米物体提供模板，并允许切换电导率和光学特性。通过使适度单分散的聚合物棒与两亲物复合也能观察到结构层次。最后，正如最近的观察结果所表明的，使用胶体颗粒在更大长度尺度上的自组装可以与上述结构相结合。
