光学高分子薄膜纳米结构与性能关系的探讨

应用AFM及力曲线的统计方法(forcecurvemethod)和Tapping/Phase功能,比较系统地研究了Glass/ITO基底上旋涂厚度为5μm的非线性光学功能高分子薄膜。结果发现,不同基底对于薄膜结构及分子构象没有明显影响。客体分子(molecule-2)在常温条件下能够以氢键的方式镶嵌在主体高分子(molecule-1)链上的—OH官能团周围和相邻的分子链间,形成特征的纳米级带状结构。ITO基底上非线性光学功能高分子薄膜在160～180℃条件下和经3000V强电场极化后,客体分子和主体高分子不同程度地进行了化学交联反应,生成新的非线性光学高分子;薄膜的微观结构由常温时的带状结构变为纳米环状结构,膜表面呈现出均匀平滑的表面形貌,并获得了理想的电光性能信号。分子键合类型的变化使得薄膜的组分发生了变化,并引起了薄膜的微观结构的改变。力曲线的统计方法和Phase的相关信息为此提供了重要证据。

Study on Connection Between Nanostructures and Properties from Optical Polymer Thin Films

The nonlinear optical(NLO)polymer thin films with thickness of 5 μm on spin coating Glass/ITO substrates were studied using AFM/Force curve method and Tapping/Phase. It is found that structures of the polymer thin films were not influenced obviously by different substrates. The guest-molecule(molecule-2)may be inlayed on the -OH group of the NLO polymer chain backbone through hydrogen bond at the room temperature. The molecule-2 also exists between the two nearest host-polymer chains. The band like nanostructure would be formed. The molecule-2 would be cross-linked with the NLO polymer(molecule-1)at 160～180 ℃ and 3000 V electronic field polarization. The characteristic configuration of the NLO polymer chain would be fixed. At the same time the cyclic nanostructure can be formed in the polymer thin film. The topography of the thin films shows continuous polymer region with very strong electronic optical signals. The change in the microstructure depends on composition of the NLO polymer thin films. The force curve method and phase mode provide very important proof.