PH regulator, water-based steel structure anticorrosive coating containing the pH regulator and capable of preventing weld joint flash rust and preparation method

Abstract

The invention relates to the technical field of anticorrosive coating, and particularly discloses a pH regulator, water-based steel structure anticorrosive coating containing the pH regulator and capable of preventing weld joint flash rust and a preparation method. The pH regulator is prepared from DMAE, water and a strong alkali aqueous solution of active metal according to a mass ratio of (1-5):(1-2):(0.1-0.5). The water-based steel structure anticorrosive coating is prepared from the following raw materials in parts by weight: 30-40 parts of polymer emulsion, 15-25 parts of an antirust filler, 10-20 parts of talcum powder, 0.1-1 part of an anti-flash-rust assistant, 0.1-1.5 parts of the pH regulator and 20-30 parts of water. The water-based steel structure anticorrosive coating not onlycan prevent flash rust of a common steel structure main body, but also has a remarkable inhibition effect on the flash rust at a weld joint, can effectively inhibit the flash rust of the weld joint,thoroughly solves the problem of rapid corrosion in the use process of the water-based coating, and is good in long-term storage stability.

Description

Technical field [0001] The invention relates to the technical field of anti-corrosion coatings, in particular to a pH regulator and a water-based anti-corrosion coating for steel structures containing the same for preventing weld flash rust and a preparation method. Background technique [0002] Metal rust and corrosion is a complicated process. Taking metallic iron as an example, there are two types of rust corrosion of iron: oxygen absorption corrosion and hydrogen evolution corrosion. [0003] Iron is prone to oxygen-absorbing corrosion in neutral solutions, alkaline solutions, and weakly acidic electrolyte solutions, and oxygen-absorbing corrosion is more common. The main reaction formula of oxygen absorption corrosion is as follows: [0004] Negative electrode (Fe): 2Fe-4e - = 2Fe 2+ ; [0005] Positive electrode (C): O 2 +4e - +2H 2 O = 4OH - ; [0006] Total reaction formula: 2Fe+O 2 +2H 2 O = 2Fe(OH) 2 . [0007] As Fe(OH) 2 Unstable, easy to be O 2 Oxidation to Fe(OH) 3 , Fe(...

AI Technical Summary

Problems solved by technology

But the disadvantage is that it is not environmentally friendly, toxic, pollutes water resources, and is suppressed by all aspects of society, especially nitrite is prone to lose anti-flash rust inhibitory activity in water-based systems

The second type is the product compounded by organic polymer amines. The commonly used ones are organic zinc chelates, which show strong affinity to iron substrates and prevent flash rust. Organic zinc chelates are coated on the surface of metal substrates. After that, it can effectively grab the free metal ions on the metal surface, form an anion passivation layer, and effectively prevent the oxidation of cathode metal ions; The effect of the area is not good, it is difficult to completely eliminate the appearance of rust spots

[0017] To sum up, the water-based steel structure coatings currently on the market tend to have better flash rust inhibition on the main body of the steel structure, and there will be no rust spots when sprayed on a large area, but more often appear at the weld seam of the steel structure. Rust spots, there are very few products that can effectively prevent welds from rusting. Even if there are, the problem is temporarily solved by adding a large amount of anti-flash rust additives. While the cost increases, the storage stability of the product is also poor

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