Fabrication of active corrosion protection waterborne polyurethane coatings using cerium modified palygorskite nanocontainers

The development of eco-efficient and environmental friendly active anti-corrosion coatings for metallic substrates represents a fundamental milestone in many engineering applications. Herein, a new type of active corrosion protection coating was successfully synthesized simply based on waterborne polyurethane (WPU) and nanocontainer of Ce 3+ modified palygorskite (Ce-PAL). Particularly, the nanocontainer of Ce-PAL was achieved via a facile and green process by cation exchange in water. Inductively coupled plasma atomic emission spectrometry (ICP) revealed that Ce 3+ had successfully incorporated into PAL nanofibers with a loading amount of 10.334 g/kg. The salt immersion test, electrochemical potentiodynamic measurements and electrochemical impedance spectroscopy (EIS) demonstrated that the incorporation of Ce-PAL only with 2 wt% into WPU led to a significant improvement of their corrosion protection properties. Finally, according to the results of scanning electron microscopy with energy dispersive X-ray spectroscopy, the active anti-corrosion mechanism of Ce-PAL/WPU coating was proposed.