Self-healing polyurethane anticorrosive coatings based on alkyd resin microcapsules

In this paper, self-healing microcapsules were prepared by in situ polymerization using poly(vinyl alcohol) as the emulsifier, urea-formaldehyde resin as the shell material, and alkyd resin as the core material. The average diameter of the obtained microcapsules was about 20 mu m and the encapsulation rate of alkyd resin was 50.7 wt.%. The self-healing coating was prepared by adding 5 wt.% of microcapsules to the pure polyurethane coating and then coated on AA2024-T3 substrate. The self-healing effect was evaluated by scanning electron microscopy. Electrochemical impedance spectroscopy tests and neutral salt spray tests confirmed that the self-healing coating had good anticorrosion properties. Alkyd resin microcapsules with an average particle size of 20 mu m were prepared by in-situ polymerization. The polyurethane coating with alkyd resin microcapsules has good self-healing effect. image