Fabrication of intelligent anticorrosion waterborne aluminum pigments based on encapsulation of composited zeolitic imidazole framework layers

In this paper, the waterborne aluminum pigments with intelligent anticorrosion properties and bright colors were prepared by encapsulating multifunctional composite layers, which were composed of zeolitic imidazole framework (ZIF) and silica. With the results of the micropores and microcracks generated in the silica layer, the penetration of acidic corrosion into the inner layer caused the ZIF layer to release the linker as the corrosion inhibitor and construct a new barrier on the metal surface due to the high corrosion inhibitor content in ZIF. After the pH response, the highest impedance of the aluminum pigments was up to 4.35 x 10(5) ? cm(2). The aluminum pigments with the multifunctional composite layers (Al@ZIF-B@SiO2) could maintain stability at pH = 1. Meanwhile, the excellent adsorption and porosity of ZIF were applied to sorb the dye, which endowed the aluminum pigments with bright colors. The functional composite layers on the aluminum pigments eliminated the hydrogen emission, which proved the excellent chemical stability of the prepared samples. The sensitive pH responsiveness of Al@ZIF-B@SiO2 was also testified.