Polyethylenimine-assisted exfoliation of h-BN in aqueous media
Researchers have investigated the polyethylenimine-assisted exfoliation of h-BN in aqueous media for anticorrosive reinforcement of water-borne epoxy coating.
PEI-BNNSs can significantly enhance the corrosion resistance of waterborne epoxy coatings. Image source: ende11.photo – stock.adobe.com (symbol image).
-In the study h-BN powders were sonicated in an aqueous solution of polyethylenimine (PEI) to simultaneously exfoliate and functionalise h-BN nanosheets with Lewis acid-base interaction.
Enhancing the corrosion resistance
The structure and morphology of PEI modified h-BN nanosheets (PEI-BNNSs) were characterised by FTIR, TGA, AFM and TEM. The as-prepared PEI-BNNSs were served as anticorrosive nanofillers for waterborne epoxy (EP) coatings on Q235 carbon steel. The corrosion behaviors of EP and PEI-BNNSs/EP coating systems in 3.5 wt % NaCl aqueous solution were evaluated by electrochemical workstation.
It is worth noting that the protection efficiency (PE) values of 1 wt % PEI-BNNSs/EP and 2 wt % PEI-BNNSs/EP coating systems are as high as 99.99 % compared to EP coating systems. Moreover, the impedance modulus (|Z|f = 0.01 Hz) of the 1 wt % PEI-BNNSs/EP coating system was 3–4 orders of magnitude higher than the EP coating after 90 days of immersion.
The electrochemical results revealed that PEI-BNNSs can significantly enhance the corrosion resistance of waterborne epoxy coatings.
The study has been published in Progress in Organic Coatings, Volume 142, May 2020.
