Novel Inorganic, Layered Aluminum tri-polyphosphate (ATP) Intercalated with N-containing inhibitors for Anti-corrosion Applications

摘要

Currently, organic coatings serve as a key method of metal protection against corrosion. In recentyears numerous attempts have been made to improve the corrosion protection of coatings withdifferent types of pigments, i.e. nano materials, metal oxides and layered materials [1]. Thesepigments can easily dissolve in water followed by precipitation of a passive oxide film on the metalsurface [2].In this context, aluminum dihydrogen tri-polyphosphate (ATP) with the compositionAlH_2P_3O_(10)·2H_2O is one of several inorganic phosphate ion exchangers with a typical layeredstructure that can be used advantageously for intercalation. The material itself has been widelyused in the coating industry as anti-corrosion pigment due to its low solubility in water [3].In order to improve the solubility and corrosion inhibition efficiency of ATP, several physical andchemical modifications were carried out. In the present work, ATP was modified with variousorganic molecules (i.e. amines, amino acids) via an intercalation process to obtain novel anticorrosionpigments with enhanced inhibition efficiency. Structural characterization, morphology etc.of the resulting system was performed by X-ray diffraction, thermal gravimetric analysis (TGA) andSEM.First results for the modified polyphosphate materials coated on low-carbon steel as a combinationof alkyd resin revealed improved anticorrosive properties using electrochemical impedancespectroscopy (EIS) and potentiodynamic polarization (PP) in a 3 mass % NaCl solution.