A waterborne epoxy zinc powder coating, a preparation method and application thereof

Abstract

The application provides a water-based epoxy zinc powder coating, a preparation method and application thereof. The water-based epoxy zinc powder coating comprises an A component and a B component. The A component comprises a water-based epoxy resin, a molecular sieve activated powder, zinc powder, an antirust pigment, MXene and graphene. The B component comprises a water-based amine curing agent. By adding MXene and graphene in the A component to produce a synergistic effect, the water-based epoxy zinc powder coating obtained can still have excellent corrosion resistance under the premise that the graphene and zinc powder addition amounts are both low, and the water-based epoxy zinc powder coating also has excellent adhesion, salt spray resistance and water resistance, and is suitable for being applied to the surface of a base material as a corrosion-resistant coating.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coatings, and particularly relates to a water-based epoxy zinc powder coating as well as a preparation method and application thereof. BACKGROUND

[0002] Epoxy zinc-rich primer is a special coating composed of epoxy resin and zinc powder as main raw materials, and thickening agent, filler, additive and solvent, etc. It plays an important role in the field of heavy-duty corrosion protection. A large amount of zinc powder is usually added, which will cause certain harm to the environment and human safety due to the large amount of zinc powder. In addition, the corrosion resistance of the epoxy zinc-rich primer is difficult to meet the application in some extreme environments. Therefore, how to reduce the amount of zinc powder and improve the corrosion resistance is the main development direction at present.

[0003] Graphene is considered to be an effective solution to the above problems due to its excellent electrical conductivity and sheet structure. CN108795235A discloses a graphene-modified water-based epoxy zinc-rich coating as well as a preparation method and application thereof. The coating comprises component A and component B. Component A is composed of the following components in mass fraction: polyamide curing agent 3-8 parts; thixotropic agent I 1-2 parts; dispersing agent 0.1-1 part; zinc powder 50-90 parts; filler 0-30 parts; solvent 5-10 parts. Component B is composed of the following components in mass fraction: water-based epoxy resin emulsion 60-70 parts; water-based graphene slurry 5-20 parts; anti-flash rust agent 1-3 parts; defoaming agent 1-3 parts; thixotropic agent II 0.1-0.5 parts; water 20-35 parts. The mass fraction of graphene in the water-based graphene slurry is 5-10%. The coating provided by the application is modified by using water-based graphene slurry, has excellent corrosion resistance and physical properties under the condition of reducing the amount of zinc powder. However, graphene has poor water dispersibility, and the addition amount in the water-based system is limited, so it is difficult to play a greater role in the water-based epoxy zinc-rich coating.

[0004] At present, there are mainly two methods to solve the dispersion problem of graphene in the water-based epoxy zinc-rich coating. One is to add a dispersing agent to improve the water dispersibility of graphene. The main disadvantage of this method is that the introduction of the dispersing agent seriously affects the water resistance and corrosion resistance of the subsequent paint film. The other is to chemically modify graphene. Although this method improves the water dispersibility of graphene, it also sacrifices the electrical conductivity and stability of the sheet structure of graphene.

[0005] Therefore, in order to solve the above technical problems, it is urgent to develop a water-based epoxy zinc powder coating with low zinc powder and graphene addition amount, and excellent corrosion resistance. SUMMARY

[0006] In view of the deficiencies of the prior art, the present application aims to provide a water-based epoxy zinc powder coating, a preparation method and application thereof, the water-based epoxy zinc powder coating comprising component A and component B, by adding MXene and graphene in component A for synergistic cooperation, the water-based epoxy zinc powder coating obtained still has excellent corrosion resistance under the condition that the addition amounts of graphene and zinc powder are both low.

[0007] To achieve this purpose, the present application adopts the following technical solutions:

[0008] In a first aspect, the present application provides a water-based epoxy zinc powder coating, the water-based epoxy zinc powder coating comprising component A and component B;

[0009] The component A comprises water-based epoxy resin, molecular sieve activated powder, zinc powder, anti-rust pigment, MXene and graphene.

[0010] The component B comprises water-based amine curing agent.

[0011] The water-based epoxy zinc powder coating provided by the present application comprises component A and component B, the component A comprises water-based epoxy resin, molecular sieve activated powder, zinc powder, anti-rust pigment, MXene and graphene, and the component B comprises water-based amine curing agent; by adding MXene in component A, MXene is a two-dimensional material, and by utilizing its excellent barrier property, high specific surface area, excellent electrical and mechanical properties, and excellent water dispersibility, a synergistic effect can be generated with graphene, the addition amounts of graphene and zinc powder can be effectively reduced, the water-based epoxy zinc powder coating obtained still has excellent corrosion resistance, and at the same time, the water-based epoxy zinc powder coating also has excellent adhesion, salt spray resistance and water resistance, and is suitable for being applied to the surface of a substrate as a corrosion-resistant coating.

[0012] Preferably, the component A comprises the following components according to weight parts:

[0013]

[0014] The water-based epoxy resin can be 12 parts by weight, 14 parts by weight, 16 parts by weight, 18 parts by weight, 20 parts by weight, 22 parts by weight or 24 parts by weight, etc.

[0015] The molecular sieve activated powder can be 0.3 parts by weight, 0.4 parts by weight, 0.5 parts by weight, 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight or 0.9 parts by weight, etc.

[0016] The zinc powder can be 27 parts by weight, 29 parts by weight, 31 parts by weight, 35 parts by weight, 37 parts by weight, 39 parts by weight, 41 parts by weight or 43 parts by weight, etc.

[0017] The rust-preventive pigment can be in quantities of 15 parts by weight, 20 parts by weight, 25 parts by weight, 30 parts by weight, or 35 parts by weight.

[0018] The MXene can be 0.07 parts by weight, 0.1 parts by weight, 0.3 parts by weight, 0.5 parts by weight, 0.7 parts by weight, or 0.9 parts by weight, etc.

[0019] The graphene may be 0.07 parts by weight, 0.1 parts by weight, 0.3 parts by weight, 0.5 parts by weight, 0.7 parts by weight, or 0.9 parts by weight, etc.

[0020] Preferably, the epoxy equivalent of the waterborne epoxy resin is 190-500 g / equivalent, such as 210 g / equivalent, 230 g / equivalent, 250 g / equivalent, 270 g / equivalent, 300 g / equivalent, 350 g / equivalent, 400 g / equivalent, or 450 g / equivalent.

[0021] Preferably, the epoxy resin has a solid content of ≥70%, such as 72%, 74%, 76%, or 78%.

[0022] Preferably, the molecular sieve activation powder includes type 3A molecular sieve activation powder and / or type 4A molecular sieve activation powder.

[0023] Preferably, the zinc powder has a particle size ≥ 800 mesh, such as 820 mesh, 840 mesh, 860 mesh, 880 mesh, or 900 mesh.

[0024] Preferably, the anti-rust pigment includes any one or a combination of at least two of zinc phosphate, zinc molybdenum phosphate, calcium phosphate, strontium phosphate, mica iron oxide, or iron phosphate powder.

[0025] Preferably, the MXene includes any one or a combination of at least two of M2X, M3X2 or M4X3, more preferably M3X2, where M is selected from any one or a combination of at least two of Ti, Cr, Mo, V or Ni, and X is selected from C and / or N.

[0026] Preferably, the MXene comprises Ti3C2.

[0027] Preferably, the graphene is multilayer graphene powder.

[0028] Preferably, the number of layers in the multilayer graphene powder is ≤10, for example, 9, 7, 5 or 3.

[0029] Preferably, the particle size of the multilayer graphene powder is ≤5μm, such as 4.5μm, 4μm, 3.5μm, 3μm, 2.5μm, 2μm, 1.5μm or 1μm.

[0030] Preferably, component A further includes any one or a combination of at least two of the following: defoamer, dispersant, antisettling agent A, or cosolvent.

[0031] Preferably, the content of defoamer in component A is 0.1 to 1 part by weight, for example, 0.2 parts by weight, 0.4 parts by weight, 0.6 parts by weight or 0.8 parts by weight.

[0032] Preferably, the defoamer includes any one or a combination of at least two of the following: silicone defoamers, polymer defoamers, or mineral oil defoamers.

[0033] Preferably, the content of dispersant in component A is 0.2 to 2 parts by weight, for example, 0.5 parts by weight, 1 part by weight, or 1.5 parts by weight.

[0034] Preferably, the dispersant is an aqueous dispersant, and more preferably a polymeric dispersant.

[0035] Preferably, the solid content of the dispersant is ≥60%, such as 62%, 64%, 66%, 68%, or 70%.

[0036] Preferably, the content of anti-settling agent A in component A is 0.5 to 2.5 parts by weight, such as 0.7 parts by weight, 0.9 parts by weight, 1.2 parts by weight, 1.4 parts by weight, 1.6 parts by weight, 1.8 parts by weight, 2 parts by weight, 2.2 parts by weight, or 2.4 parts by weight.

[0037] Preferably, the anti-settling agent A comprises any one or a combination of at least two of organobentonite, magnesium silicate, fumed silica, or polyamide wax.

[0038] Preferably, the content of the co-solvent in component A is 1 to 10 parts by weight, such as 2 parts by weight, 4 parts by weight, 6 parts by weight, or 8 parts by weight.

[0039] Preferably, the co-solvent includes any one or a combination of at least two of alcohol co-solvents, alcohol ether co-solvents, or alcohol ester co-solvents.

[0040] Preferably, component B comprises the following components in parts by weight:

[0041] 3 to 15 parts by weight of water-based amine curing agent.

[0042] The water-based amine curing agent can be 4 parts by weight, 6 parts by weight, 8 parts by weight, 10 parts by weight, 12 parts by weight, or 14 parts by weight, etc.

[0043] Preferably, the water-based amine curing agent includes any one or a combination of at least two of epoxy-modified amines, aliphatic amines, cashew phenol-modified amines, or phenolic amines.

[0044] Preferably, the water-based amine curing agent contains ≥70% by mass of non-volatile substances, such as 75%, 80%, or 85%, where the mass percentage of non-volatile substances is the same as the mass percentage of the active ingredient, i.e., the mass percentage of the actual substance that can participate in the curing reaction.

[0045] Preferably, component B further includes any one or a combination of at least two of the following: flash rust inhibitor, anti-settling agent B, or water.

[0046] Preferably, the content of flash rust inhibitor in component B is 0.5 to 2.5 parts by weight, such as 0.7 parts by weight, 0.9 parts by weight, 1.2 parts by weight, 1.4 parts by weight, 1.6 parts by weight, 1.8 parts by weight, 2 parts by weight, 2.2 parts by weight, or 2.4 parts by weight.

[0047] Preferably, the flash rust inhibitor is an organic flash rust inhibitor.

[0048] Preferably, the content of anti-settling agent B in component B is 0.1 to 1 part by weight, such as 0.2 parts by weight, 0.4 parts by weight, 0.6 parts by weight, or 0.8 parts by weight.

[0049] Preferably, the anti-settling agent B comprises any one or a combination of at least two of the following: dispersed bentonite, fumed silica, attapulgite, or montmorillonite.

[0050] Preferably, the water content in component B is 1 to 10 parts by weight, such as 2 parts by weight, 4 parts by weight, 6 parts by weight, or 8 parts by weight.

[0051] Preferably, the water is deionized water.

[0052] Preferably, the mass ratio of component A to component B is (5-15):1, for example, 7:1, 9:1, 11:1 or 13:1.

[0053] In a second aspect, the present invention provides a method for preparing a waterborne epoxy zinc powder coating as described in the first aspect, the method comprising:

[0054] Aqueous epoxy resin, optionally dispersant and optionally cosolvent are mixed, MXene and graphene are added and mixed, molecular sieve activating powder, optionally anti-settling agent A and optionally defoamer are added and mixed, and finally zinc powder is added and mixed to obtain component A;

[0055] A water-based amine curing agent, optionally a flash rust inhibitor, and optionally an anti-settling agent B are mixed in water to obtain component B.

[0056] Preferably, the mixing of the aqueous epoxy resin, optionally the dispersant and optionally the cosolvent is carried out under stirring conditions at a speed of 400 to 1000 rpm (e.g., 500 rpm, 600 rpm, 700 rpm, 800 rpm or 900 rpm).

[0057] Preferably, the mixing time for mixing the aqueous epoxy resin, optionally the dispersant and optionally the cosolvent is 10 to 20 minutes, for example, 12 minutes, 14 minutes, 16 minutes or 18 minutes.

[0058] Preferably, the addition of MXene and graphene is carried out at a rotation speed of 2000-3000 rpm (e.g., 2200 rpm, 2400 rpm, 2600 rpm or 2800 rpm).

[0059] Preferably, the mixing time for adding MXene and graphene is 30 to 50 minutes, such as 32 minutes, 34 minutes, 36 minutes, 38 minutes, 40 minutes, 42 minutes, 44 minutes, 46 minutes, or 48 minutes.

[0060] Preferably, the addition of molecular sieve activating powder, optionally anti-settling agent A, and optionally defoamer is carried out under stirring conditions at a speed of 1000-2000 rpm (e.g., 1200 rpm, 1400 rpm, 1600 rpm, or 1800 rpm).

[0061] Preferably, the mixing time for adding molecular sieve activating powder, optionally anti-settling agent A and optionally defoamer is 15 to 30 minutes, such as 17 minutes, 19 minutes, 21 minutes, 23 minutes, 25 minutes, 27 minutes or 29 minutes.

[0062] Preferably, the final addition of zinc powder for mixing is carried out under stirring conditions of 1000-2000 rpm (e.g., 1200 rpm, 1400 rpm, 1600 rpm or 1800 rpm).

[0063] Preferably, the mixing time for adding zinc powder at the end is 15 to 60 minutes, such as 20 minutes, 25 minutes, 30 minutes, 35 minutes, 40 minutes, 45 minutes, 50 minutes, or 55 minutes.

[0064] Preferably, the fineness of the final slurry after adding zinc powder is ≤60μm, such as 55μm, 50μm, 45μm, 40μm or 35μm.

[0065] Preferably, the water-based amine curing agent, optionally flash rust inhibitor, and optionally anti-settling agent B are mixed in water under stirring conditions of 1000-1500 rpm (e.g., 1100 rpm, 1200 rpm, 1300 rpm, or 1400 rpm).

[0066] Preferably, the mixing time for mixing the water-based amine curing agent, optionally flash rust inhibitor and optionally anti-settling agent B in water is 15 to 30 minutes, such as 17 minutes, 19 minutes, 21 minutes, 23 minutes, 25 minutes, 27 minutes or 29 minutes.

[0067] Thirdly, the present invention provides an application of the waterborne epoxy zinc powder coating as described in the first aspect as an anti-corrosion coating.

[0068] Compared with the prior art, the present invention has the following beneficial effects:

[0069] (1) The waterborne epoxy zinc powder coating provided by the present invention includes component A and component B. Component A includes waterborne epoxy resin, molecular sieve activated powder, zinc powder, anti-rust pigment, MXene and graphene. Component B includes waterborne amine curing agent. By adding MXene to component A to produce a synergistic effect with graphene, the waterborne epoxy zinc powder coating can still have excellent corrosion resistance while effectively reducing the amount of graphene and zinc powder added. It also has excellent adhesion, salt spray resistance and water resistance, and is suitable as an anti-corrosion coating for use on the substrate surface.

[0070] (2) The water-based epoxy zinc powder coating provided by the present invention has excellent storage stability, the appearance of the coating film after film formation is normal, the surface drying time is 15-20 min, the actual drying time is 8-12 h, the salt spray resistance is as high as 2500-3000 h, the adhesion to the substrate is as high as 8.5-10.5 MPa, the water resistance is as high as 1000-1500 h, and the workability is qualified. The early water resistance and flash rust inhibition are both normal. Detailed Implementation

[0071] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention in any way.

[0072] The following is some information about the raw materials involved in the specific embodiments of the present invention:

[0073] Waterborne epoxy resin: EP138, Qirun New Materials;

[0074] Molecular sieve activated powder: 3A, GRACE;

[0075] Defoamer: 901W, Evonik Chemicals;

[0076] Dispersants: 6208, Zhanxin;

[0077] Zinc powder: average particle size 800 mesh, general commercial use;

[0078] Rust-preventive pigment: Phosphorus iron powder, general commercial use;

[0079] Anti-settling agent A: SD-2, Hemings Chemical;

[0080] MXene: Ti3C2, Beike New Materials;

[0081] Graphene: SE1132, Changzhou Sixth Element;

[0082] Cosolvent: PM, Dow Chemical;

[0083] Water-based amine curing agent: 38-1, Huntsman;

[0084] Flash rust inhibitor: 515, HALOX;

[0085] Anti-settling agent B: EW, Hemings Chemical.

[0086] Examples 1-9

[0087] A water-based epoxy zinc powder coating includes component A and component B. The total amount of components A and B is 100 parts by weight. The specific components are shown in Table 1. The unit of measurement for each component in Table 1 is "parts by weight".

[0088] Table 1

[0089]

[0090]

[0091] The preparation methods of the waterborne epoxy zinc powder coatings provided in Examples 1-9 include:

[0092] (1) Place the cosolvent, dispersant and waterborne epoxy resin in a clean reactor with circulating cooling water, mix for 10 min under stirring at 600 r / min, add MXene and graphene while stirring, mix for 40 min under stirring at 3000 r / min, then add anti-settling agent A, defoamer and molecular sieve activation powder in sequence, mix for 20 min under stirring at 2000 r / min, finally add zinc powder, mix for 20 min under stirring at 2000 r / min, so that the fineness of the slurry is ≤60 μm, and obtain component A;

[0093] (2) Mix water-based amine curing agent, flash rust inhibitor, anti-settling agent B and deionized water for 20 min under stirring conditions at a speed of 1400 r / min to obtain component B.

[0094] Comparative Examples 1-3

[0095] A water-based epoxy zinc powder coating includes component A and component B. The total amount of components A and B is 100 parts by weight. The specific components are shown in Table 2. The unit of measurement for each component in Table 2 is "parts by weight".

[0096] Table 2

[0097]

[0098] The preparation methods of the waterborne epoxy zinc powder coatings provided in Comparative Examples 1 to 3 are as described in Example 1.

[0099] Performance testing:

[0100] After mixing components A and B in the waterborne epoxy zinc powder coatings provided in the examples and comparative examples according to their actual weight parts, water was added to dilute the mixture so that the viscosity of the waterborne epoxy zinc powder coating was ≤60KU, and then the following tests were performed.

[0101] (1) Condition in container and appearance of paint film: Test according to the test method provided in HG / T 3668;

[0102] (2) Drying time: Tested according to the test method provided in GB / T 1728;

[0103] (3) Salt spray resistance: Tested according to the test method provided in GB / T 1771;

[0104] (4) Adhesion: Tested according to the test method provided in GB / T 1720;

[0105] (5) Water resistance: Tested according to the test method provided in GB / T 1733;

[0106] (6) Workability: High-pressure airless spraying is used. The paint film surface is free of abnormalities and drips and is easy to spray. Otherwise, it is unqualified.

[0107] (7) Early water resistance and flash rust inhibition: Tested according to the test method provided in HG / T 3668.

[0108] The waterborne epoxy zinc powder coatings provided in Examples 1-9 and Comparative Examples 1-3 were tested according to the above test methods, and the test results are shown in Table 3.

[0109] Table 3

[0110]

[0111]

[0112] According to the data in Table 3:

[0113] The waterborne epoxy zinc powder coating provided by this invention has excellent storage stability, and after film formation, it has excellent corrosion resistance, salt spray resistance and water resistance, while also having high adhesion to the substrate.

[0114] Specifically, the water-based epoxy zinc powder coatings provided in Examples 1 to 7 were all in normal condition in the container, indicating that they have good water dispersibility. After film formation, the appearance of the coating film was normal, and the surface drying time was 15 to 20 minutes, the actual drying time was 8 to 12 hours, the salt spray resistance was as high as 2500 to 3000 hours, the adhesion to the substrate was as high as 8.5 to 10.5 MPa, the water resistance was as high as 1000 to 1500 hours, and the workability was qualified. There were no abnormalities in early water resistance and flash rust inhibition.

[0115] Compared with Example 3, the waterborne epoxy zinc powder coatings provided in Comparative Examples 1 and 3, due to the absence of graphene, had a salt spray resistance of only 800-1500h, an adhesion of only 8MPa, and a water resistance of only 700-800h. The early water resistance and flash rust inhibition tests also showed abnormalities, indicating that the addition of graphene is crucial.

[0116] Compared with Example 3, the waterborne epoxy zinc powder coating provided in Comparative Example 2 had white particles floating out during storage, and white spots and pinholes appeared on the surface of the coating film after film formation, indicating that the waterborne epoxy zinc powder coating without MXene has poor water dispersibility and poor storage stability.

[0117] Compared with Example 3, the salt spray resistance, water resistance and substrate adhesion of the waterborne epoxy zinc powder coatings provided in Examples 8-9 also decreased after film formation, indicating that the addition ratio of MXene and graphene also affects the performance of the waterborne epoxy zinc powder coating. Only when the two are added within the range defined by this invention can they exert their synergistic effect to the greatest extent.

[0118] The applicant declares that this invention illustrates a water-based epoxy zinc powder coating, its preparation method, and its application through the above embodiments. However, this invention is not limited to the above embodiments, meaning that this invention does not necessarily rely on the above embodiments for implementation. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials, additions of auxiliary components, and selection of specific methods, etc., all fall within the protection and disclosure scope of this invention.

Claims

1. An aqueous epoxy zinc dust coating, characterized in that, The water-based epoxy zinc dust paint comprises an A component and a B component; The A component comprises a water-based epoxy resin, a molecular sieve activated powder, zinc dust, an anti-rust pigment, MXene and graphene; The B component comprises a water-based amine curing agent; The A component comprises the following components by weight: The water-based epoxy resin is 10-25 parts by weight; The molecular sieve activated powder is 0.2-1 part by weight; The zinc dust is 25-45 parts by weight; The anti-rust pigment is 10-40 parts by weight; The MXene is 0.05-1 part by weight; The graphene is 0.05-1 part by weight; The B component comprises the following components by weight: The water-based amine curing agent is 3-15 parts by weight; The mass ratio of the A component to the B component is (5-15):

1.

2. The aqueous epoxy zinc dust coating according to claim 1, characterized in that, The epoxy equivalent weight of the water-based epoxy resin is 190-500 g / equivalent.

3. The aqueous epoxy zinc dust coating according to claim 1, characterized in that, The solid content of the epoxy resin is ≥70%.

4. The aqueous epoxy zinc dust coating according to claim 1, characterized in that, The molecular sieve activated powder comprises a 3A type molecular sieve activated powder and / or a 4A type molecular sieve activated powder.

5. The aqueous epoxy zinc dust coating of claim 1, wherein, The particle size of the zinc dust is ≥800 mesh.

6. The aqueous epoxy zinc dust coating of claim 1, wherein, The anti-rust pigment comprises any one or a combination of at least two of zinc phosphate, zinc molybdate phosphate, calcium phosphate, strontium phosphate, mica iron oxide or phosphorus iron powder.

7. The aqueous epoxy zinc dust coating of claim 1, wherein, The MXene comprises any one or a combination of at least two of M2X, M3X2 or M4X3, M is selected from any one or a combination of at least two of Ti, Cr, Mo, V or Ni, and X is selected from C and / or N.

8. The aqueous epoxy zinc dust coating of claim 1, wherein, The MXene is M3X2, M is selected from any one or a combination of at least two of Ti, Cr, Mo, V or Ni, and X is selected from C and / or N.

9. The aqueous epoxy zinc dust coating of claim 1, wherein, The MXene comprises Ti3C2.

10. The aqueous epoxy zinc dust coating of claim 1, wherein, The graphene is a multi-layer graphene powder.

11. The aqueous epoxy zinc dust coating according to claim 10, characterized in that The number of layers of the multi-layer graphene powder is ≤10.

12. The aqueous epoxy zinc dust coating of claim 10, wherein, The particle size of the multi-layer graphene powder is ≤5 μm.

13. The aqueous epoxy zinc dust coating of claim 1, wherein, The A component further comprises any one or a combination of at least two of a defoaming agent, a dispersant, an anti-settling agent A or a cosolvent.

14. The aqueous epoxy zinc dust coating according to claim 13, characterized in that, The content of the defoaming agent in the A component is 0.1-1 part by weight.

15. The aqueous epoxy zinc dust coating of claim 13, wherein, The defoaming agent comprises any one or a combination of at least two of a polymer-based defoaming agent or a mineral oil-based defoaming agent.

16. The aqueous epoxy zinc dust coating of claim 13, wherein, The content of the dispersant in the A component is 0.2-2 parts by weight.

17. The aqueous epoxy zinc dust coating of claim 13, wherein, The dispersant is a water-free dispersant.

18. The aqueous epoxy zinc dust coating of claim 13, wherein, The dispersant is a high-molecular dispersant.

19. The aqueous epoxy zinc dust coating of claim 13, wherein, The solid content of the dispersant is ≥60%.

20. The aqueous epoxy zinc dust coating of claim 13, wherein, The content of the anti-settling agent A in the A component is 0.5-2.5 parts by weight.

21. The aqueous epoxy zinc dust coating of claim 13, wherein, The anti-settling agent A comprises any one or a combination of at least two of organic bentonite, magnesium silicate, fumed silica or polyamide wax.

22. The aqueous epoxy zinc dust coating of claim 13, wherein, The content of the cosolvent in the A component is 1-10 parts by weight.

23. The aqueous epoxy zinc dust coating of claim 13, wherein, The cosolvent comprises any one or a combination of at least two of an alcohol-based cosolvent, an alcohol ether-based cosolvent or an alcohol ester-based cosolvent.

24. The aqueous epoxy zinc dust coating of claim 1, wherein, The water-based amine curing agent comprises any one or a combination of at least two of an epoxy-modified amine, a fatty amine, a cashew phenol-modified amine or a phenolic amine.

25. The aqueous epoxy zinc dust coating of claim 1, wherein, The mass percentage content of non-volatile substances in the water-based amine curing agent is ≥70%.

26. The aqueous epoxy zinc dust coating of claim 1, wherein, The B component further comprises any one or a combination of at least two of a flash rust inhibitor, an anti-settling agent B or water.

27. The aqueous epoxy zinc dust coating of claim 26, wherein, The content of the flash rust inhibitor in the B component is 0.5-2.5 parts by weight.

28. The aqueous epoxy zinc dust coating of claim 26, wherein, The flash rust inhibitor is an organic flash rust inhibitor.

29. The aqueous epoxy zinc dust coating of claim 26, wherein, The content of the anti-settling agent B in the B component is 0.1-1 parts by weight.

30. The aqueous epoxy zinc dust coating of claim 26, wherein, The anti-settling agent B comprises any one or a combination of at least two of dispersed bentonite, fumed silica, attapulgite or montmorillonite.

31. The aqueous epoxy zinc dust coating of claim 26, wherein, The content of water in the B component is 1-10 parts by weight.

32. The aqueous epoxy zinc dust coating of claim 26, wherein, The water is deionized water.

33. A method of preparing an aqueous epoxy zinc dust coating according to any one of claims 1 to 32, characterized in that The preparation method comprises: mixing the aqueous epoxy resin, optionally a dispersant and optionally a co-solvent, adding MXene and graphene for mixing, further adding molecular sieve activated powder, optionally an anti-settling agent A and optionally an antifoaming agent for mixing, and finally adding zinc powder for mixing to obtain the A component; mixing the aqueous amine curing agent, optionally a flash rust inhibitor and optionally an anti-settling agent B in water to obtain the B component.

34. The preparation method according to claim 33, characterized in that, The mixing of the aqueous epoxy resin, optionally a dispersant and optionally a co-solvent is carried out under stirring at a rotation speed of 400-1000 rpm.

35. The preparation method according to claim 33, characterized in that, The mixing time of the mixing of the aqueous epoxy resin, optionally a dispersant and optionally a co-solvent is 10-20 min.

36. The preparation method according to claim 33, characterized in that, The mixing of the MXene and graphene is carried out at a rotation speed of 2000-3000 rpm.

37. The preparation method according to claim 33, characterized in that, The mixing time of the mixing of the MXene and graphene is 30-50 min.

38. The method of claim 33, wherein the method is performed in a single step. The further mixing of the molecular sieve activated powder, optionally an anti-settling agent A and optionally an antifoaming agent is carried out under stirring at a rotation speed of 1000-2000 rpm.

39. The method of claim 33, wherein, The mixing time of the further mixing of the molecular sieve activated powder, optionally an anti-settling agent A and optionally an antifoaming agent is 15-30 min.

40. The method of claim 33, wherein, The final mixing of the zinc powder is carried out under stirring at a rotation speed of 1000-2000 rpm.

41. The method of manufacturing according to claim 33, wherein, The mixing time of the final mixing of the zinc powder is 15-60 min.

42. The method of claim 33, wherein, The fineness of the slurry after the final mixing of the zinc powder is ≤60 μm.

43. The method of claim 33, wherein the method is carried out at a temperature of about 20°C to about 30°C. The mixing of the aqueous amine curing agent, optionally a flash rust inhibitor and optionally an anti-settling agent B in water is carried out under stirring at a rotation speed of 1000-1500 rpm.

44. The method of claim 33, wherein the method is performed in a single step. The mixing time of the mixing of the aqueous amine curing agent, optionally a flash rust inhibitor and optionally an anti-settling agent B in water is 15-30 min.

45. Use of the aqueous epoxy zinc powder coating as claimed in any one of claims 1-32 as a corrosion-resistant coating.

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