Preparation and Application of Polyurea Nanocapsules Used for Intelligent Anti-corrosion Coating

The hollow polyurea nanocapsules loaded with 1H-benzotriazole (BTA) were fabricated by interfacial polyaddition of the monomers toluene-2, 4-diisocyanate (TDI) and diamine in water-in-oil (W/O) inverse miniemulsion. Morphology and heat-sensitive of the polyurea nanocapsules were respectively characterized by Transmission Electron Microscopy (TEM) and Differential Scanning Calorimetry (DSC). Results showed that a sufficient storage of BTA was wrapped into the hollow particles, which can be released timely through degradation of the nanocapsules with azo bands by stimuli of temperature or UV-light. The enhanced anti-corrosive effect of the organic film embedded with the nanocapsules was obtained, which was investigated by electrochemical measurement performed using Electrochemical Impedance Spectrum (EIS) and Tafel analysis.