Study on Corrosion Resistant Properties of Nano-SiO<sub>2</sub> Modified Epoxy Coating

Nano-SiO 2 which surface was modified by silane coupling agent was used to modify the epoxy coatings which was prepared by the method of chemical modification and physical dispersion using the modified nano-SiO 2 and epoxy. The molecular structure and dispersity of the modified nano-SiO 2 were studied by Fourier transform spectra(FT-IR) and scanning electron microcopy(SEM). The effect of nano-SiO 2 on corrosion resistance of epoxy coating was studied by electrochemical impedance spectroscopy(EIS). The results show that the modified nano-SiO 2 contained the Si-OH characteristic functional group which can promoted the nano-SiO 2 grafted with epoxy and had a good dispersion; Compared to epoxy coatings, wear rate of the modified epoxy coating reduced about 20% and the impedance value of the modified epoxy coating using the method of soak in 3.5% solution of NaCl for 240h, improved by 5 orders of magnitude.