Ref.: MpoCo15-001

Epoxy coatings loaded with sodium montmorillonite modified with zinc-based ionic liquid and their self-healing and anti-corrosive properties

Apresentador: Jean Carlos Carelo

Autores (Instituição): Henriques, R.R.(Universidade Federal do Rio de Janeiro); Carelo, J.C.(Universidade Federal do Rio de Janeiro); Soares, B.G.(Universidade Federal do Rio de Janeiro);

Resumo:
In this study, the efficiency of corrosion resistance in coated steel and the self-healing ability in epoxy coatings loaded with 1% sodium montmorillonite (MMT-Na+), clay treated with bis-(1-butyl-3-methylimidazolium) zinc tetrachloride (bmim2[ZnCl4]) was investigated. Comparative analyses were conducted with other treatments to examine the protective and self-healing effects in superficially damaged ER coatings containing 1% MMT-bmim2[ZnCl4], MMT-bmimCl, and MMT-ZnCl2, using electrochemical impedance spectroscopy (EIS) in saline medium. The inclusion of 1% clay modified with ZnCl2 and bmim2[ZnCl4] resulted in excellent corrosion protection in the damaged ER coatings. These coatings exhibited the best anti-corrosive response, with a |Z|f=0.01Hz value approximately at 3.0 × 106 ??cm2 after 24 hours of immersion, significantly increasing after 360 hours.Additionally, the charge transfer resistance increased after 360 hours of immersion, along with a notable reduction in double-layer capacitance values at the electrolyte/metal interface. The self-healing ability was further validated through SEM/EDX analyses and visual inspection of the scratched area following 360 hours of immersion in saline solution. Pull-off adhesion tests were conducted to assess the effectiveness of the ER/MMT-Modified coatings in protecting the metallic substrate.