Corrosion inhibition of AA2024-T3 by smart polyelectrolyte coacervates
A new study describes the corrosion inhibition of AA2024-T3 by smart polyelectrolyte coacervates responsive to both acidic and alkaline environments.
AA2024-T3 substrates exhibited better corrosion resistance. Image source: analogicus - Pixabay (symbol image).
-Previously reported pH-responsive corrosion-protective coatings based on the layer-by-layer assembled polyelectrolytes responded to the pH increase caused by cathodic reactions in corrosion but were less sensitive to the pH decrease in anodic regions.
Better corrosion resistance
In this study, polyacrylic acid was directly added into polyethylenimine to make polyelectrolyte coacervates capable of releasing SrCrO4 inhibitor at both acidic and alkaline pH. Due to a higher amount of the released SrCrO4 at both low and high pH, AA2024-T3 substrates exhibited better corrosion resistance during cyclic potentiodynamic polarisation compared with that in neutral pH chloride solutions.
Electrochemical impedance spectroscopy further proved that the corrosion resistance of AA2024-T3 was improved by the application of SrCrO4-embedded polyelectrolyte coacervates. The developed polyelectrolyte coacervates open a pathway for creating a release system for corrosion protection of AA2024-T3 triggered by low and high pH in a facile and fast way.
The study has been published in Progress in Organic Coatings, Volume 146, September 2020.
Image source: Pixabay.
