An eco-friendly and pH response cerium-based melamine phytate (PM) nanosheets with active and passive anticorrosion ability in water-borne epoxy coating

摘要

Herein, an environmental protection nanocontainer based on Ce(III) was prepared in aqueous media to build an active (inhibitive)/passive (barrier) anti-corrosion packing (PC). To provide "smart" feature for composited nanofillers, a pH response material polydopamine (PDA) has been introduced to form an adhesive network (PCD). Then, the obtained nanofillers were introduced to the waterborne epoxy matrix (WEP). Results of UV-vis experiments show that Ce ions display the largest release at pH = 3 from the PCD framework. After 30 days immersion, the PCD/WEP still exhibits the highest log|Z|0.01Hz value (about 9 0 cm2), which is much higher than blank WEP (6 0 cm2). With artificial scratches on coating surface, the cracks on PCD/WEP were nearly disappeared compared with other samples after 720 hrs immersion. In addition, SEM-EDS results of corrosion area show that the total content of corrosive ions (Cl, O) on the metal surface coated by PCD/WEP are under 10%. This research not only highlights the promising application of PM nanosheets, but also broadens the application of PM nanosheets as a nanocontainer.

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