Preparation of Polyimide/Inorganic Nanoparticle Hybrid Films by Sol–Gel Method

Abstract

In this study polyimide/inorganic silica–alumina nanoparticle hybrid films are first prepared by sol–gel method to find a promising method for enhancing thermal property and other properties. Silica sol and alumina sol starting from tetraethoxysilicane (TEOS) and aluminum isopropylate (AIP) are doped in a solution of poly (amic acid). The hybrid films are obtained by a stepwise heating method. The structure, micro-morphology, and thermal properties of the films are characterized by Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The micrographs show uniform distribution of club shaped particles in the films containing silica and alumina. The micrographs of polyimide/silica hybrid films revealed sphericity and uniform distribution of particles. Al2O3 particles are poorly dispersed and are prone to agglomerate in the polyimide/alumina hybrid films. Moreover, there are chemical bonds between inorganic and organic phases in the hybrid films. The thermodecomposition temperature of the hybrid films is also improved markedly after the addition of silica and alumina nanoparticles.