Organic/inorganic hybrid composite films from polyimide and organosilica: Effect of the type of organosilica precursors

We report the influence of the type of organosilica precursors on the growth of organosilica domains and the interfacial interaction between polyimide (PI) and organosilica in PI/organosilica hybrid composite films. The organosilica precursors used are tetraethoxysilane (TEOS), triethoxy(ethyl)si lane (TEES), and 1,2-bis(triethoxysilyl)ethane (BTSE). The hybrid composite films were prepared by thermal imization of the precursor films that were made via sol-gel process of the mixture of poly(4,4'-oxydianiline benzenetetracarboxamic acid) (PMDA-ODA PAA) and organosilica precursors. The hybrid composite films were characterized using Fourier transform infrared (FT-IR) spectra, Si-29 cross polarization (CP) MAS-NMR spectra, field emission-scanning electron microscopy (FE-SEM), UV-visible spectra, small angle x-ray scattering (SAXS), dynamic mechanical analysis (DMA), and thermogravimetric analysis (TGA). The results showed that the TEES precursor was more pronounced in improving the interaction of corresponding organosilica with PI than other precursors.