Corrosion inhibition of flaky aluminium powders prepared through sol–gel process

In order to prevent corrosion of aluminium pigment in water, coated flaky aluminium powder was prepared through the sol–gel process, in which tetraethoxysilane (TEOS) and tris(2-methoxyethoxy)vinylsilane (VTMOEO) were adopted as precursors. The influences of the dosage of precursors, ethylenediamine, water and ethanol, as well as the reaction temperature and reaction time on the corrosion inhibition efficiency were investigated. Under the optimum conditions, the corrosion inhibition efficiency reached 99.2% in alkaline media of pH 11. The analysis with SEM, FTIR, EDS and XPS showed that sol–gel coatings had successfully encapsulated on the surface of clear flaky aluminium powders.

Research highlights
► Coated flaky aluminium powder with high corrosion inhibiting efficiency in alkaline media was prepared.
► Tris(2-methoxyethoxy)vinylsilane (VTMOEO) was also used as precursor in sol-gel process because VTMOEO could improve the compatibility with resins through crosslinking.
► For preparing coated flaky aluminium powder, the optimum condition was obtained through single-factor experiments.