Abstract:
The natural sodium-montmorillonite was cation exchanged with dodecylammonium chloride. The poly (amic acid)s were simultaneously imidized with a dodecylamine-montmorillonite, the organophilic aluminosilicate layers, yielding polyimide-clay nanocomposites. Transmission Electron Micrographs (TEM) revealed that the alumino-silicate layers produced a fine dispersion in the polyimide matrices. Wide Angle X-ray Scattering (WAXS) patterns indicated that the interlayer spacing of an organophilic-clay expanded when the clay was dispersed in the polymer matrices. Thus, the polymer-clay hybrids can be classified as partial-exfoliated nanocomposite. Thermal stability, in-plane thermal expansion, water resistivity, tensile properties, and dielectric strength of the nanocomposites were improved with increase clay content. The thermal expansion coefficients of both polyimide film and its clay nanocomposites remained the same after ten cycles of thermal treatment.