Chemical Self-healing Microcapsule for Cementitious System

To fulfil initially the intellisense and self-healing of concrete for corrosion of reinforcement by means of microcapsule technology, a novel chemical self-healing system based microcapsule technology was designed for cementitious composites, which was accompanied by a chemical trigger mechanism. The fundamental issue of this system was the smart releasing performance in cementitious environment and controlled rebar protection effectiveness against corrosion. The measurements with ethylene diamine tetraacetic acid （EDTA) titration and electrochemical impedance spectroscopy （EIS) method were applied to achieve above targets.Resultsshow that properties of microcapsule are affected by the time, the shell thickness of microcapsule and the pH-values in cementitious environment. Besides, an electrochemical model is built up to explain the anti-corrosion pattern of this microcapsule based selfhealing system.