Evaluation in Real Conditions of New Anticorrosive Formulations Based on Polyphenols from Natural Sources and Encapsulated Nanoparticles

The objective of this study was to examine the combined protection effect of a two-layer system consisting of organic corrosion inhibitors (tannins derived from the bark of radiata pine) and anodic protection by means of the incorporation of zinc oxide nanoparticles modified superficially by chemical methods to improve the protection of metallic structures against corrosion. Film evaluations are performed in accordance with ISO and ASTM standards. This study also took into account the evaluation of the performance of two commercial coatings according to the scheme suggested by the supplier, in addition to the electrochemical impedance spectroscopy (EIS) characterizations at 0 h, 720 h of accelerated exposure, and 4 months of atmospheric exposure in a corrosive environment of classification C3. The results obtained indicated that the combination of tannins derived from pine bark and encapsulated zinc oxide nanoparticles is a viable alternative to commercial coatings with a higher concentration of synthetic compounds. Although the film properties decrease slightly, performance tests at different exposure times show that they can still be classified as high-performance coatings.

Automated summary

The objective of this study was to improve the protection of metallic structures against corrosion by combining organic corrosion inhibitors (tannins derived from pine bark) with anodic protection using chemically modified zinc oxide nanoparticles. Film evaluations were conducted according to ISO and ASTM standards. The study also evaluated the performance of two commercial coatings and conducted electrochemical impedance spectroscopy (EIS) characterizations at different exposure times. The results showed that the combination of tannins and encapsulated zinc oxide nanoparticles is a viable alternative to commercial coatings with synthetic compounds, providing high-performance corrosion protection.