Dopamine(DA), one type of mussel-inspired biological molecules with adhesive nature and corrosion inhibitor property, are often used to functionalize the surfaces of various materials. Herein, we report the applicatio...Dopamine(DA), one type of mussel-inspired biological molecules with adhesive nature and corrosion inhibitor property, are often used to functionalize the surfaces of various materials. Herein, we report the application of polydopamine(PDA) microcapsules as novel nanocontainers for the purpose, loading corrosion inhibitor(benzotriazole) in its shell structure, and then were embedded into epoxy coatings to provide self-healing and anti-corrosion protection for carbon steel. Fast release of benzotriazole in acidic environment caused by local corrosion and the chelating effect of PDA-Fe^(3+)can synergistically promote the formation of protective film on bare steel surface, which endows coatings with self-healing functionality. Electrochemical impedance spectroscopy(EIS), local electrochemical impedance spectroscopy(LEIS), and spray tests were conducted to evaluate the active inhibition and corrosion resistance of the loaded coatings. The scratched coating with incorporation of nanocontainers presented better protection performance, exhibiting increased Ro(oxide layer resistance) and R ct(charge transfer resistance) during initial immersion periods. The EIS tests in long-term immersion were also performed to confirm the anti-corrosion effect of composited coatings. These results demonstrated that benzotriazole-decorated PDA capsules dramatically enhanced the self-healing properties and anti-corrosion performance of epoxy coatings with the synergistic help of PDA and benzotriazole.展开更多
基金financially supported by the National Science Fund for Distinguished Young Scholars of China(No.51825505)the National Natural Science Foundation of China(No.51905278)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA13040601)the Special Research Funding from the Marine Biotechnology and Marine Engineering Discipline Group in Ningbo University。
文摘Dopamine(DA), one type of mussel-inspired biological molecules with adhesive nature and corrosion inhibitor property, are often used to functionalize the surfaces of various materials. Herein, we report the application of polydopamine(PDA) microcapsules as novel nanocontainers for the purpose, loading corrosion inhibitor(benzotriazole) in its shell structure, and then were embedded into epoxy coatings to provide self-healing and anti-corrosion protection for carbon steel. Fast release of benzotriazole in acidic environment caused by local corrosion and the chelating effect of PDA-Fe^(3+)can synergistically promote the formation of protective film on bare steel surface, which endows coatings with self-healing functionality. Electrochemical impedance spectroscopy(EIS), local electrochemical impedance spectroscopy(LEIS), and spray tests were conducted to evaluate the active inhibition and corrosion resistance of the loaded coatings. The scratched coating with incorporation of nanocontainers presented better protection performance, exhibiting increased Ro(oxide layer resistance) and R ct(charge transfer resistance) during initial immersion periods. The EIS tests in long-term immersion were also performed to confirm the anti-corrosion effect of composited coatings. These results demonstrated that benzotriazole-decorated PDA capsules dramatically enhanced the self-healing properties and anti-corrosion performance of epoxy coatings with the synergistic help of PDA and benzotriazole.
