提出了一种新的炭纤维表面改性方法——分子自组装,即在表面金属化的炭纤维上进行有机分子的自组装。表面增强拉曼散射光谱(SERS)分析证实了含氮或含硫的芳杂环化合物化学吸附在银的表面,并形成了平躺取向的自组装膜结构。X射线光电子能谱(XPS)测试进一步证实了自组装膜通过S或N原子和Ag形成配位共价键吸附在炭纤维表面。表面经组装改性后的炭纤维和环氧复合后界面粘结强度得到了不同程度的提高,揭示了界面区域微观结构与性能的关系。
A new method based on the molecular self-assembly was proposed for the carbon fiber surface modification. The carbon fiber surface was first metallized by electroless Ag plating and then covered by organic compound self-assembly films. The surface-enhanced Raman scattering spectroscopy (SERS) analysis verifies that two nitrogen- containing or sulphur-containing aromatic heterocyclic compounds were chemisorbed onto the Ag-plated carbon fibers and formed a lie-down phase. XPS further proves the chemisorption of self-assembly films on the carbon fiber surface via the formation of S-Ag or N-Ag bonds. The interfacial bonding strengths of modified carbon fiber/epoxy composites are improved. The relationship between the structures of interfacial regions and properties of the micro- composites is revealed.