Abstract:

Zircoaluminate coupling agent with carboxy groups was synthesized, with polyaluminium chloride, zirconium oxychloride and adipic acid, etc. , as the materials. The product and the nano-sized TiO2 before and after the surface modification were then characterized by means of FT-IR, TG-DTG, XRD, TEM and by measuring the size distribution. It is found that one carboxy group in adipic acid forms a complex bridge between the aluminum and the zirconium centers, while the other remains unchanged as the functional group of the coupling agent; and that the proportion of inorganic parts in the coupling agent is up to 71%. Moreover, as for the nano-sized ZiO2 surface-modified with the coupling agent, there exists a chemical adsorption of the coupling agent on TiO2 surface, which has no effect on the crystalline form of nano-sized TiO2, and, the dispersion of the modified nano-sized TiO2 in water improves remarkably.

Key words: zireoaluminate coupling agent, synthesis, nano-sized titanium dioxide, surface modification, interface property, dispersion