| 초록 |
Recently, one-dimensional (1-D) nanomaterials including nanotubes, nanowires, and nanorods have attracted significant attention due to their unique properties and potential applications. By using templates, such as anodic aluminum oxide (AAO) membranes, different 1-D nanomaterials have been generated inside the cylindrical nanopores of the templates. Template-based methods represent straightforward routes to 1-D nanomaterials. The template is simply used as a scaffold within which a different material is fabricated and shaped by the geometry of the template. While metallic and inorganic semiconductor nanomaterials are routinely made, the preparation of polymer and polymer-related nanomaterials using templates has been less studied. Here, we study the fabrication and characterization of different polymer-related nanomaterials by wetting porous templates. The templates we choose are anodic aluminum oxide (AAO) templates because of the regular pore distribution, high pore density, and high aspect ratio of the pores. Different nanomaterials such as amorphous carbon nanotubes, amphiphilic block copolymer nanotubes, and porous inorganic materials are fabricated by using these templates. Hierarchical polymer nanostructures are also made by wetting the porous template with polymer microspheres. We also investigate the wetting behavior of the polymer solution or melt inside the nanopores. We report a systematic study of the wetting of cylindrical alumina nanopores with polystyrene melts. A transition from partial to complete wetting was observed with increasing annealing temperature, resulting in the formation of very different one-dimensional polymeric nanostructures (nanorods and nanotubes) within cylindrical alumina nanopores. The wetting transition temperature is dependent on the polymer molecular weight. The large difference in the wetting rate between partial and complete wetting was successfully used to fractionate polymers with different molecular weights. In addition, we study the instabilities of polymer nanomaterials under confinement within the cylindrical pores of the template. The instability phenomenon which is driven by surface energy also provides a new route for generating novel polymer nanomaterials. |
