Effects of inorganic content and morphology between phases on structure and properties of the hybrid polyimide film

In this paper, a type of nano-hybrid polyimide/silica film was prepared by hydrolysis and condensation of methyl-triethoxysilane that served as the precursor of the inorganic moiety and produced the nano-particle of silica, in-situ, in the polyamic acid solution through a sol-gel reaction. The chemical structure and surface morphology of the films were characterized by Fourier transform infrared spectroscopy and Atomic force microscopy respectively. The properties of the films, such as thermal stability and corona-resistance property were investigated as a function of the SiO₂ content. The structure-property response on the hybrid system was also discussed. The result of the experiments indicate that the properties of the nano-hybrid materials were not only relative to the inorganic component content of the system, but also to the morphology between the inorganic and organic phases and the character of the interface. It proved that a strong interaction existed between the two phases when a coupling agent is added into the polyimide/silica composite system and that it would play a significant role in improving the miscibility between the two phases, and in reducing the size of the inorganic particles. It also showed that no apparent change had occurred in the thermal decomposition temperature of the hybrid film and the corona-resistance property of the hybrid film had greatly improved as a result of the inorganic component being added into polyimide resin matrix