Preparation Process of Epoxy Resin Microcapsules for Self - healing Coatings

The self-healing microcapsules were prepared by in-situ polymerization with urea formaldehyde resin and epoxy resin E-5l as the wall material and core material separately in this paper. The effects of the amount of epoxy resin, sodium dodecyl benzene sulfonate (SDBS), ammonium chloride, resorcinol and the stirring rate on the particle size of microcapsules were discussed. The microcapsules were added into the epoxy resin composite coating for corrosion resistance evaluation. The results showed that when the ratio of epoxy resin to urea was 24%, the amount of SDBS was 8%, the amount of ammonium chloride was 5.6%, the content of resorcinol was 10.4% and the stirring speed was 450 rpm, the average particle size of the capsules was 55.7 μm. When the addition number of microcapsules was 2% in the coating, the corrosion resistance was best with its service life prolonged by about 4 times.