Characterization of Fly Ash Modified with Vinyltriethoxysilane

Here we repor t on the modification of fly ash (FA) with vinyltr iethoxysilane (VTES) in order to enhance the dispersibility and avoid the agglomeration. FA was treated with nitr ic acid before the modification with VTES. The str ucture of fly ash par ticles before and after the modification was character ized by several sophisticated techniques including Four ier transfor m infra-red spectrum (FT-IR), ther mogravimetr ic analysis (TGA), field emission scanning electron microscopy (FE-SEM)and size distr ibution analysis. The obtained results show that the VTES was grafted successfully onto the surface of FA, which significantly changes the surface proper ties of FA. It was also foundthat the ther mal stability of modified FA (MFA) is much higher than that of the FA treated only with nitric acid. The size of the FA par ticles can also be controlled from 0.2 to 1.5  m with increasing the loading of VTES on the surface of FA from 1 to 2 wt.%, revealing highly mono-distr ibution andlow agglomeration. However, the agglomeration of the par ticles is obser ved when the content of VTES on the surface of FA exceeds 2 wt.%.