A smart poly(aniline-formaldehyde) microcapsule based self-healing anticorrosive coating

Abstract

The effectiveness of linseed oil and mercaptobenzothiazole (MBT) encapsulated poly(aniline-formaldehyde) [PAF] microcapsules was investigated for healing of cracks generated in paint/coatings. Microcapsules were prepared by in situ polymerization of aniline-formaldehyde resin to form a shell over the linseed oil and mercaptobenzothiazole. Characterizations of these capsules were studied by FTIR, TGA, and Scanning Electron Microscopy (SEM). EIS studies of the artificial defect area have shown that the coating containing microcapsules is able to protect steel in neutral media since the impedance values remained at 1.287 × 10⁸ Ω cm² even after 15 days exposure whereas the coatings without microcapsules lost their protection ability. The self healing ability of the coating containing microcapsules was studied by SVET.