Preparation and characterization of polyimide/silica hybrid films

A kind of hybrid polyimide films was prepared by synthesizing poly (amic acid)/Silica matrix resin through sol-gel technique and then followed by positing it on a silex glass plate and drying at high temperature. The effect of silica content on the corona-resistant property of the films was studied. The miscibility between the organic and inorganic phases and its effect on the corona-resistant property were investigated with aminopropyl-triefhoxysilane, which served as a coupling agent, added into the polyimide composite system. The chemical structure and the surface morphology of the films were characterized by FTIR and AFM respectively. The corona-resistant property of the films was tested by a rod-plate electrode. It proved that the corona-resistant property was enhanced with silica content. It also turned out that the improvement of the miscibility between the two phases due to the presence of covalent force as a result of the addition of the coupling agent had, to some extent, effect on the corona-resistant property of the films. Furthermore, a theory on the corona-resistant property was put forward preliminarily.