TEM, XPS and thermo-mechanical properties of novel sustainable hybrid coatings

This work contributes to the development of a new generation of protective coatings composed of organic-inorganic materials. A silica based hybrid film was used in this work as high performance materials. The silica sol-gel film reveals enhanced thermo-mechanical properties in comparison with the pure polymer film. Herein, we demonstrate the possibility of employing cheap SiO2 as prospective nano-fillers for hybrid coatings with active thermo-mechanical properties. Organic-inorganic hybrid coatings based on polyimide and silica were synthesized through a simple physical mixing technique. 3,3′,4,4′-Biphenyltetracarboxylic dianhydride (BPDA), benzene-1,3-diamine (BDA), 3,3′-oxydianiline (ODA) and SiO2, were used as precursors for the hybrid coatings. These hybrid coatings were deposited via spin coating onto a galvanized iron, aluminum and copper in order to study the adhesive strength. The effects induced by the silica content on the mechanical properties of the coated samples were investigated. The mechanical properties of hybrid composite were found to be enhanced compared to polyimide coating. The main objective was to observe potential improvements in the mechanical and thermal properties of PI-silica hybrid films. Morphology, and structural changes in the composite films were studied as well as adhesion and impact strength and these characteristics were compared with those of unreinforced polyimide films.