作者：D. Chen, S. Huang, C. Zhang, W. Z. Wang, T. X. Liu*.
关键字：Layer-by-layer assembly, Layered double hydroxide (LDH), Ultrathin films, Polyimide, X-ray diffraction, Atomic force microscopy.
论文来源：期刊
具体来源：Thin Solid Films, 2010, 518(24), 7081-7085.
发表时间：2010年

The layer-by-layer (LBL) self-assembly has been extensively used as a simple and effective method for the preparation of polyelectrolyte multilayer films. In this work, we utilized this unique method to prepare polyimide precursor/layered double hydroxide (LDH) ultrathin films. Well-crystallized Co–Al–CO3 LDH and subsequent anion exchanged Co–Al–NO3 LDH were prepared and characterized by scanning electron microscopy and X-ray diffraction (XRD). By vigorous shaking of the as-prepared Co–Al–NO3 LDH, positively charged and exfoliated LDH nanosheets were obtained. Atomic force microscopy and XRD investigations indicated the delamination of LDH nanosheets. The precursor of polyimide, poly(amic acid) tertiary amine salt (PAS) was prepared by the polycondensation of dianhydride and diamine, and subsequent amine salt formation. By using the LBL method, heterogeneous ultrathin films of PAS and LDH were prepared. The formation of the ordered nanostructured assemblies was confirmed by the progressive enhancement of UV absorbance and the XRD results.