A novel modification of superhydrophobic surfaces using supercritical carbon dioxide

在超临界二氧化碳中，将由全氟烷基丙烯酸酯和商业单体组成的无规共聚物自组装而成的球形粒子进行涂层，得到了超疏水表面。无规共聚物在浊点以下以非均相状态自组装成纳米球。核磁共振谱表明，纳米球具有全氟烷基链的壳层和商业单体单元的核心。包覆纳米球的表面是超疏水的，具有164°以上的高水接触角。含氨基的无规共聚物通过双官能团酸静电交联，得到的超疏水表面最大，为171.5°。结果表明，这种超疏水性是基于全氟烷基链的疏水性与球状结构的相关性，因为铸膜层的接触角只有96.5°。此外，为了获得更高的疏水表面，确定了一种具有环境友好性质的新型光活性自由基聚合。

Superhydrophobic surfaces were obtained by coating with spherical particles formed by the self-assembly of random copolymers consisting of perfluoroalkyl acrylate and commercial monomers in supercritical carbon dioxide. The random copolymers self-assembled into nano-sized spheres in the heterogeneous state below the cloud points. The ^1NMR demonstrated that the nanospheres had the shelles of perfluoroalkyl chains and the cores of the commercial monomer units. The surfaces coated with the nanospheres were superhydrophobic and showed high water contact angles over 164°. The most superhydrophobic surface was 171.5° obtained from the random copolymer containing amino groups cross-linked electrostatically by a bifunctional acid. It was found that this superhydrophobicity was based on the correlation of the hydrophobicity by the perfluoroalkyl chains and the spherical structure because the cast film showed only 96.5° of the contact angle. Furthermore, in order to obtain much higher hydrophobic surface, a novel photo-living radical polymerization that had environmental benign nature was determined.