Preparation method of graphene composite anticorrosive coating

Abstract

The invention discloses a preparation method of a graphene composite anticorrosive coating. The preparation method comprises the following steps: (1) preparing an organic coating solution with a plurality of hydroxyls or amino groups; (2) preparing an oxidized graphene or modified graphene solution; (3) performing metal surface pretreatment; (4) performing electrodeposition to form an organic coating film; and (5) preparing the graphene composite anticorrosive coating. The method is simple and feasible in technology, the film forming speed is obviously improved, and the prepared coating is more compact and uniform; compared with a plain sample, the low-frequency impedance modulus value of the prepared composite coating is improved to 10<6.2> from 10<3.5> by performing electrochemical testing in 3.5wt% NaCl neutral electrolyte solution, the self-corrosion current is also remarkably reduced, and longer effective prevention effect on a matrix can be achieved. Compared with the conventional dip-coating method, the preparation method has lower requirement on the flatness of a metal surface, and controllable preparation can be effectively realized; the prepared coating is non-toxic and environment-friendly, controllable in thickness, and more compact and uniform, and more durable and stable protection effect on the metal matrix can be achieved.

Description

technical field [0001] The invention relates to the technical field of metal anticorrosion, in particular to a preparation method of a graphene composite anticorrosion coating. Background technique [0002] Metal corrosion is a phenomenon of deterioration or destruction caused by chemical or electrochemical interactions between metals and the surrounding environment. Metal corrosion has caused serious harm to the national economy and social life. Material corrosion causes damage to metal equipment and engineering structures, and the economic loss is much greater than the cost of the material itself if it is withdrawn from service in advance. The annual direct economic loss due to metal corrosion accounts for about 4.2% of the gross national product, and the metal materials scrapped due to corrosion account for about 1 / 10 of the annual metal production in the world. [0003] The traditional metal surface treatment technology is mainly chromate treatment and phosphate treatm...

AI Technical Summary

Problems solved by technology

[0007] Coatings prepared by traditional dip coating or spin coating are limited by thickness and uniformity, and cannot provide lasting protection to the metal substrate.

In addition, due to the limitations of the protection of the metal substrate by a single functional siloxane film (such as: insufficient thickness, porosity, etc.), the corrosion protection ability of its long-term use alone is limited.

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