Progress in Organic Coatings | 2019
Enhancing corrosion resistance of epoxy coating on steel reinforcement by aminobenzoate intercalated layered double hydroxides
Abstract
Abstract This paper aims to examine the corrosion resistance of epoxy coating incorporated with aminobenzoate intercalated Mg-Al layered double hydroxides (LDH) on steel reinforcement in simulated concrete pore solution. Mg-Al LDH intercalated with aminobenzoate was fabricated by calcination-rehydration method. Besides, the open-circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) of the steels with the epoxy coatings containing aminobenzoate intercalated Mg-Al LDH were measured. Also, the microstructures of epoxy coatings with aminobenzoate intercalated LDH were observed by scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The results show that Mg-Al LDH intercalated with aminobenzoate has been successfully synthesized by using the calcination-rehydration method. The incorporation of aminobenzoate intercalated Mg-Al LDH with proper dosage increases obviously the corrosion resistance of epoxy coating. The ultimate corrosion resistances of all the coatings have a sequence of 0.5\u2009wt% LDH\u2009>\u20091\u2009wt% LDH\u2009>\u2009neat epoxy\u2009>\u20092%wt LDH. The microstructure variations in the epoxy coatings due to the addition of Mg-Al LDH are contributed to the change of the corrosion resistance.