Vinyl ester resins (VER) are commonly used in the field of anticorrosive coatings. During the preparation and application of the coatings, it is inevitable to produce defects such as micro-porosity, micro-cracks, and scratches, which will reduce the barrier capacity of the anticorrosive coatings against corrosive media. In this paper, 2-(chloromethyl) pyridine is used to functionalize the silane-decorated graphene oxide for obtaining the functionalized modified graphene oxide (TGO). The aggregation of TGO nanosheets under the influence of Fe2+ ions generated by corrosion, achieving the response closure of TGO/VER coatings to hinder the diffusion path of corrosive media, thereby strengthening the anticorrosion effect of the coating. The water vapor transmission rate of TGO/VER coatings decreases significantly after immersion in Fe2+ solution. Electrochemical impedance spectroscopy tests indicate that TGO/VER coatings have better corrosion resistance compared with VER coatings, in which the impedance modulus after immersion for 100 d of 0.3TGO/VER coatings (3.93 × 1010 Ω cm2) is about four orders of magnitude greater than that of the VER coatings (5.85 × 106 Ω cm2). The TGO/VER coatings provide the responsive closure function via complexation of TGO with Fe2+ to achieve the long-term corrosion resistance. These results suggest that TGO/VER system provides an effective strategy for the preparation and application of graphene-based long-term anticorrosive coatings.
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