A New Smart Additive of Reinforced Concrete Based on Modified Hydrotalcites: Preparation, Characterization and Anticorrosion Applications

摘要

A carbonate form of Mg-Al-hydrotalcite and its p-aminobenzoate (pAB) modified derivative (i.e.,Mg(2)Al-pAB) were synthesized and characterized by means of XRD and FT-IR. The anticorrosion behavior was evaluated based on open circuit potential (OCP) of carbon steel in simulated concrete pore solution and chloride-exchange experiments. The preliminary results shown in this study demonstrated that ion-exchange indeed occurred between chlorides and the intercalated pAB anions in Mg(2)Al-pAB structure, thereby reducing the free chloride concentration in simulated concrete pore solution. The simultaneously released inhibitive pAB anions were found to exhibit the envisaged inhibiting effect and caused corrosion initiation of the steel shifting to a higher chloride concentration than without the modified hydrotalcites.