Synthesis and Properties of Organosoluble Polyimide/Clay Hybrids

摘要

A soluble polyimide prepared from 7,7'-bis(4-aminophenoxy)-4,4,4,'4'-tetramethyl-2,2'-spirobichroman and 4,4'-hexafluoroisopropylideediphthalic anhydride was mixed with organo-modified montmorillonite or synthetic mica in N,N-dimethyla-cetamide. The content of the clay minerals were 1, 2, and 4 wt5, respectively. Transparent, flexible, and tough films could be cast form the hybrid solutions. The hybrid films were characterized with wide-angle X-ray scattering (WAXS), transmission electron microscopy, thermomechanical analyssi, thermogravimetric analysis, and differentical scanning calorimetry. The WAXS results revealed that the montmorillonite was dispersed more homogeneously that the synthetic mica in the polyimide matrix. In both polyimide/clay hybrids the addition of clay caused thermal expansion coefficients to decrease, and the thermal stability was slightly enhanced.