Corrosion inhibition of AA2024-T3 by a coating containing dual-pH sensitive, corrosion inhibitor loaded microspheres

In this study, we describe a smart coating that responds to either an increase or a decrease in pH to assist inhibitor effectiveness. Dual-pH sensitive microspheres containing a corrosion inhibitor were fabricated using a simple, template-free, one-step process. A polyelectrolyte coacervate consisting of polyacrylic acid and polyethylenimine was the shell material of microspheres that enclosed Ce(NO3)3 inhibitor using a coaxial electrospray method. The Ce(NO3)3-loaded microspheres with a core-shell structure can release Ce(NO3)3 at both acidic and alkaline pH. A smart coating consisting of these microspheres embedded in a polyvinyl butyral coating releases Ce(NO3)3 to improve the corrosion resistance of AA2024-T3.