A fast-drying thick paste waterborne epoxy two-component anticorrosive coating and its preparation method

Abstract

The present invention discloses a fast-drying thick-film waterborne epoxy two-component anticorrosive coating and its preparation method, belonging to the technical field of coating preparation; it includes Component A: waterborne epoxy resin, wetting and dispersing agent, calcium carbonate, mica powder, modified sepiolite, graphene oxide, modified basalt fiber, nano-silica and metal powder; Component B: curing agent; when preparing Component A, sepiolite is added to the silane coupling agent, and after sufficient reaction, graphene oxide is added. After sufficient reaction, it is filtered, washed and dried. The dried product is added to the silica aqueous solution, and after sufficient reaction, a dried product is obtained; then the waterborne epoxy resin, wetting and dispersing agent and deionized water are mixed, and then calcium carbonate, mica, the dried product, modified basalt fiber and metal powder are added, and Component A is obtained after sufficient dispersion; the coating of the present invention has extremely excellent adhesion, water resistance, acid resistance, and neutral salt spray resistance at 150 °C, and can significantly shorten the drying time of the coating.

Description

Technical Field

[0001] The present invention relates to the technical field of coating preparation, in particular to a fast-drying thick-film waterborne epoxy two-component anti-corrosion coating and a preparation method thereof. Background Art

[0002] Epoxy thick-film coatings have excellent rust and corrosion resistance, good physical and mechanical properties, excellent wear resistance, impact resistance, seawater resistance, salt spray resistance, and good water penetration resistance. They are suitable for anti-corrosion of the hulls, ballast tanks, crude oil tanks, and sewage tanks of ships, and can also be used for anti-corrosion of reinforced concrete.

[0003] After being coated, epoxy thick-film coatings generally require fast drying. If the drying speed is too slow, the coating will have large fluidity and will sag or drool, resulting in a decrease in the coating uniformity and the bonding force with the interface, thus affecting the coating performance. However, if the drying speed is too fast, due to the thick coating of the thick-film coating, after the surface of the paint film is quickly cured, the internal solvent is difficult to quickly discharge, resulting in insufficient curing of the inner layer and causing defects. At the same time, due to the serious uneven drying inside and outside the coating, phenomena such as skinning, foaming, and cracking will occur on the surface of the coating, seriously affecting the use of the coating. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a fast-drying thick-film waterborne epoxy two-component anti-corrosion coating and a preparation method thereof, so as to at least achieve the purpose of improving the volatilization speed of the internal solvent and the drying uniformity of the coating during the fast-drying process, while reducing the phenomena of skinning, foaming, and cracking on the coating surface.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] A fast-drying thick-film waterborne epoxy two-component anti-corrosion coating, comprising component A and component B, wherein component A comprises the following components:

[0007] Waterborne epoxy resin, wetting and dispersing agent, calcium carbonate, mica powder, modified sepiolite, graphene oxide, modified basalt fiber, nano-silica, and metal powder;

[0008] The preparation method of the modified sepiolite is as follows: first, sepiolite is calcined, and then it is modified with a silane coupling agent;

[0009] The preparation method of the modified basalt fiber is as follows: basalt fiber is added to a nano-silica solution modified with a silane coupling agent, and after sufficient reaction, it is dried.

[0010] Component B comprises a curing agent.

[0011] As some feasible embodiments of the present application, component A comprises the following components in parts by weight:

[0012] 30 - 50 parts of waterborne epoxy resin, 0.3 - 1 part of wetting and dispersing agent, 5 - 20 parts of calcium carbonate, 15 - 30 parts of mica powder, 5 - 15 parts of modified sepiolite, 5 - 10 parts of graphene oxide, 2 - 5 parts of modified basalt fiber, 3 - 8 parts of nano-silica, and 2 - 5 parts of metal powder.

[0013] As some feasible embodiments of the present application, the component A includes the following components in parts by weight:

[0014] 35 - 45 parts of waterborne epoxy resin, 0.5 - 0.95 part of wetting and dispersing agent, 8 - 18 parts of calcium carbonate, 18 - 25 parts of mica powder, 8 - 13 parts of modified sepiolite, 6 - 9 parts of graphene oxide, 2.5 - 4 parts of modified basalt fiber, 4 - 7 parts of nano-silica, and 2.5 - 4.5 parts of metal powder.

[0015] As some feasible embodiments of the present application, the component A includes the following components in parts by weight:

[0016] 43 parts of waterborne epoxy resin, 0.9 part of wetting and dispersing agent, 16 parts of calcium carbonate, 20 parts of mica powder, 12 parts of modified sepiolite, 8 parts of graphene oxide, 3.5 parts of modified basalt fiber, 5.5 parts of nano-silica, and 3 parts of metal powder.

[0017] As some feasible embodiments of the present application, the calcium carbonate is calcium carbonate modified by a silane coupling agent.

[0018] As some feasible embodiments of the present application, the mica powder is mica powder modified by a silane coupling agent.

[0019] As some feasible embodiments of the present application, the metal powder is one or more of Cr, Ni, V, and Ti.

[0020] In addition, to achieve the above object, the present invention also provides a preparation method for a fast-drying thick-film waterborne epoxy two-component anticorrosive coating. The preparation method of the component A is as follows:

[0021] S1 Mix the silane coupling agent and deionized water, then add calcined sepiolite. After sufficient reaction, add graphene oxide. After sufficient reaction, filter, wash, and dry. Add the dried product to the silica aqueous solution. After sufficient reaction, filter, wash, and dry to obtain a dried product;

[0022] S1 Mix the waterborne epoxy resin, wetting and dispersing agent, and deionized water, then add calcium carbonate, mica, the dried product, modified basalt fiber, and metal powder to the mixed solution. After sufficient dispersion, obtain the component A.

[0023] Compared with the prior art, the beneficial effects of the present invention are:

[0024] The present invention provides a group of coatings comprising waterborne epoxy resin, wetting and dispersing agent, calcium carbonate, mica powder, modified sepiolite, graphene oxide, modified basalt fiber, nano-silica, metal powder and curing agent, which have extremely excellent adhesion, water resistance, acid resistance and salt spray resistance; meanwhile, the surface drying time of the coatings in the present invention is 15 - 22 min, and the through drying time is 78 - 105 min, significantly shortening the drying time of the coatings, greatly reducing the drooling phenomenon of the coatings during the drying process, thereby improving the uniformity of the coating. After the coatings are cured, there are no obvious skinning, blistering or cracking phenomena on the coating surface. Detailed implementation manners

[0025] The technical solutions in the embodiments of the present application will be clearly and completely described below. Apparently, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the scope of protection of the present application.

[0026] In the prior art, thick-film coatings generally require fast drying. If the drying speed is too slow, due to the large fluidity of the coatings, sagging or drooling will occur, resulting in a decrease in the uniformity of the coating and the bonding force with the interface, thereby affecting the coating performance; however, if the drying speed is too fast, due to the thick coating of the thick-film coating, after the surface of the paint film is quickly cured, the solvent inside is difficult to be quickly discharged, resulting in insufficient curing of the inner layer and causing defects; at the same time, due to the serious uneven drying inside and outside the coating, skinning, blistering, cracking and other phenomena will occur on the surface of the coating, seriously affecting the use of the coating.

[0027] Based on this, the present invention provides a fast-drying thick-film waterborne epoxy two-component anti-corrosion coating, comprising component A and component B. Component A comprises the following components:

[0028] Waterborne epoxy resin, wetting and dispersing agent, calcium carbonate, mica powder, modified sepiolite, graphene oxide, modified basalt fiber, nano-silica and metal powder;

[0029] The preparation method of the modified sepiolite is: first calcine the sepiolite, and then modify it with a silane coupling agent;

[0030] The preparation method of the modified basalt fiber is: add basalt fiber into a nano-silica solution modified with a silane coupling agent, fully react and then dry.

[0031] Component B comprises a curing agent;

[0032] In the above solution, waterborne epoxy resin is used as the resin matrix of the coating, and calcium carbonate is used as the filler and strengthening agent of the coating, which can enhance the deposition and permeability of the paint film, and also has wear resistance, corrosion resistance, rheology, etc.; mica powder is used as the filler and whitening agent of the coating, which has good elasticity, toughness, insulation, high temperature resistance, acid and alkali resistance, corrosion resistance, and strong adhesion. Because mica powder has a flaky crystal structure with a high aspect ratio, it can lie down under the action of surface tension before the coating cures, automatically forming a structure parallel to each other and parallel to the surface of the paint film. Such a layer-by-layer arrangement has its orientation perpendicular to the direction in which corrosive substances penetrate the paint film, and the barrier effect is more fully exerted, which can effectively improve the anti-corrosion performance. However, precisely because the mica crystal has such a structure, during the rapid drying process, the diffusion and migration of the solvent in the paint film become extremely tortuous, and it mostly diffuses along the direction parallel to the paint film, thereby prolonging the drying time and aggravating the sagging phenomenon of the thick-film coating during the drying process.

[0033] Based on this, the present invention adds sepiolite that has been successively calcined at high temperature and modified with a silane coupling agent. After sepiolite is calcined at high temperature, the adsorbed water, zeolite water, crystal water, and structural water between the fibers and in the pores are removed. At this time, the silanol groups on the surface of sepiolite are transformed into a silicon oxygen tetrahedron structure, expanding the channel size inside sepiolite. After adding the calcined sepiolite to the coating, the sepiolite fibers will disperse and then freely intercalate between the flaky structures formed by mica powder. As a result, the solvent molecules can rapidly diffuse along the channels between the fiber bundles, effectively overcoming the defect in the prior art that the solvent diffuses tortuously along the interlayer structure of the mica layer, resulting in a slow diffusion rate. However, because the hydrophilic groups, silanol groups, inside sepiolite are greatly reduced during the high-temperature calcination process, it is difficult for sepiolite fibers to effectively diffuse into the waterborne epoxy matrix. Based on this, the present invention modifies the calcined sepiolite with a silane coupling agent. After modification, it can improve its affinity with epoxy resin, and can also make sepiolite show better dispersibility in epoxy resin, reducing the occurrence of agglomeration phenomena. In addition, the modified sepiolite also has acid resistance, alkali resistance, salt spray resistance, and as a thixotropic agent, it can effectively solve the problem of sedimentation of filler particles; fibrous sepiolite can also effectively fill the cracks in the coating, effectively solving the problem of coating cracking.

[0034] However, when actually implemented, adding modified sepiolite has at least the following technical defects:

[0035] First, although the modification with a silane coupling agent can improve its dispersibility in the resin matrix, because the thick-film coating itself has high requirements for the binding force of each component and its dispersion in the matrix, it is difficult to meet the dispersion and binding requirements of the thick-film coating only by modifying sepiolite with a silane coupling agent;

[0036] Second, the cellulose in the modified sepiolite is extremely fine, and it is difficult to form continuous fibers between mica layers, which in turn affects the diffusion rate;

[0037] Based on this, graphene oxide and modified basalt fibers are added to the modified sepiolite in the present invention. After adding graphene oxide, the silane coupling agent in the modified sepiolite can modify the surface of graphene oxide, so that the modified sepiolite and graphene oxide are tightly combined through the modified silane coupling agent, and at the same time, the modified sepiolite can be uniformly dispersed on the surface of graphene; because graphene oxide contains many -COOH and -OH, these active oxygen functional groups can increase its compatibility and dispersion ability with the epoxy resin matrix; at the same time, the functional groups it contains can form hydrogen bonds with the epoxy resin to improve the binding force between the two, thereby indirectly improving the binding force between the modified sepiolite and the resin matrix, and improving the dispersion uniformity of the modified sepiolite between the resin matrices. Further, graphene oxide also has high strength, high toughness, and functions such as enhancing the salt spray resistance of the coating, increasing the adhesion of the coating to the coated substrate, and improving the wear resistance of the coating.

[0038] After adding the modified basalt fibers, they can be fully inserted into the layered structure formed by graphene and mica powder to serve as a bridge between the sepiolite fiber bundles, so that continuity is formed between the sepiolite fibers and the modified basalt fibers. As a result, the solvent can diffuse along the various directions of the coating under the action of the sepiolite and the basalt fibers, thereby improving the drying speed and drying uniformity. At the same time, the added basalt fibers can be used as a reinforcing material to further increase the mechanical properties of the coating, and can also improve the corrosion resistance and high-temperature resistance of the coating.

[0039] In the prior art, in order to uniformly disperse basalt in the coating, it is often modified, such as by using a coupling agent for modification. After modification, the bridging effect of the coupling agent polymer can be used to improve the interfacial adhesion between the basalt fiber and the epoxy resin, but the interfacial bonding force generated only by this chemical connection effect is not high, and the improvement degree of the interfacial adhesion is very limited. Therefore, the basalt fibers in the present invention are modified with a nano-silica solution modified by a silane coupling agent. The nano-silica can be connected to the surface of the basalt fiber through the silane coupling agent, and the fiber surface will become rough and the specific surface area will increase, which is beneficial to the formation of a more effective meshing effect between the basalt fiber and the resin matrix, thereby improving the interfacial bonding between the basalt fiber and the resin matrix.

[0040] By adding nano-silica into the coating, which has extremely strong ultraviolet absorption and infrared reflection characteristics, it can form a shielding effect on the coating, achieving the effects of anti-ultraviolet aging and thermal aging. At the same time, it increases the heat insulation of the coating and slows down the sedimentation of coating droplets. In addition, nano-SiO2 particles can significantly improve the microstructure of the coating, enhance the anti-corrosion performance of the coating, form Si-O-Fe covalent bonds with the steel substrate, and effectively improve the bonding performance of the coating. However, during the quick-drying process of silica, the loss of water between Si-OH will form a Si-O-Si network structure, which will cause the silica sol to shrink too fast, resulting in insufficient film-forming performance. During actual preparation, the silanol groups in silica undergo a condensation reaction with the silane coupling agent in the modified sepiolite, so that sepiolite and SiO2 are connected by an organic carbon long chain, solving the problem of too fast shrinkage of the silica sol.

[0041] The metal powder added in the present invention can significantly improve the density, wear resistance and high-temperature salt spray corrosion resistance of the coating. At the same time, the volume expansion generated during the oxidation of the metal powder enables the coating to have better corrosion resistance.

[0042] In summary, by providing a coating containing waterborne epoxy resin, wetting dispersant, calcium carbonate, mica powder, modified sepiolite, graphene oxide, modified basalt fiber, nano-silica and metal powder, the present invention can effectively improve the drying speed of the coating, as well as improve the anti-corrosion performance, salt spray resistance, acid and alkali resistance, radiation resistance, etc. of the coating.

[0043] In order to further improve the anti-corrosion performance and drying speed of the coating, as some feasible embodiments of the present application, the dosages of the components of the coating are limited, that is, the A component includes the following components in parts by weight:

[0044] 30 - 50 parts of waterborne epoxy resin, 0.3 - 1 part of wetting dispersant, 5 - 20 parts of calcium carbonate, 15 - 30 parts of mica powder, 5 - 15 parts of modified sepiolite, 5 - 10 parts of graphene oxide, 2 - 5 parts of modified basalt fiber, 3 - 8 parts of nano-silica, 2 - 5 parts of metal powder and 10 - 30 parts of deionized water.

[0045] In order to further improve the anti-corrosion performance and drying speed of the coating, as some feasible embodiments of the present application, the dosages of the components of the coating are limited, that is, the A component includes the following components in parts by weight:

[0046] 35 - 45 parts of waterborne epoxy resin, 0.5 - 0.95 part of wetting dispersant, 8 - 18 parts of calcium carbonate, 18 - 25 parts of mica powder, 8 - 13 parts of modified sepiolite, 6 - 9 parts of graphene oxide, 2.5 - 4 parts of modified basalt fiber, 4 - 7 parts of nano-silica, 2.5 - 4.5 parts of metal powder and 15 - 25 parts of deionized water.

[0047] In order to further improve the anti-corrosion performance and drying speed of the coating, as some possible implementation methods of the present application, the amount of each component of the coating is limited, that is, the A component includes the following components by weight:

[0048] 43 parts of waterborne epoxy resin, 0.9 parts of wetting and dispersing agent, 16 parts of calcium carbonate, 20 parts of mica powder, 12 parts of modified sepiolite, 8 parts of graphene oxide, 3.5 parts of modified basalt fiber, 5.5 parts of nano-silicon dioxide, 3 parts of metal powder and 24 parts of deionized water.

[0049] In order to further improve the uniformity of dispersion of each component of the coating, as some possible implementation methods of the present application, the type of calcium carbonate is further limited, that is, the calcium carbonate is calcium carbonate modified by a silane coupling agent. Since nano calcium carbonate particles have high surface energy and are in a thermodynamically unstable state, they are very easy to agglomerate when directly added to the coating, so they need to be modified. After modification by a silane coupling agent, their uniformity of dispersion in the coating can be effectively improved.

[0050] In order to further improve the uniformity of dispersion of each component of the coating, as some possible implementation methods of the present application, the type of mica powder is further limited, that is, the mica powder is mica powder modified by a silane coupling agent. The surface polarity of mica powder is large, the compatibility is poor, it is easy to agglomerate and the dispersion is uneven. After modifying it, its dispersibility can be effectively improved. In addition, the mica powder preparation method of the present invention is prepared by the preparation method of application number 201811295367.5.

[0051] In order to further improve the density of the coating and improve the anti-corrosion performance, as some feasible implementation methods of the present application, the types of metal powders are further limited, and the metal powders are one or more of Cr, Ni, V, and Ti.

[0052] In addition, to achieve the above purpose, the present invention also provides a method for preparing a quick-drying thick paste water-based epoxy two-component anti-corrosion coating, wherein the preparation method of component A is as follows:

[0053] S1. Mixing a silane coupling agent and deionized water, then adding calcined sepiolite, and after sufficient reaction, adding graphene oxide, and after sufficient reaction, filtering, washing, and drying, adding the dried product to a silicon dioxide aqueous solution, and after sufficient reaction, filtering, washing, and drying to obtain a dried product;

[0054] S1: Mixing water-based epoxy resin, wetting dispersant and deionized water, and then adding calcium carbonate, mica, the dried product, modified basalt fiber and metal powder to the mixed solution, and fully dispersing them to obtain component A.

[0055] In the above solution, by adding calcined sepiolite into the silane coupling agent, the modification purpose can be achieved. By adding graphene oxide into the silane coupling agent, the surface of graphene oxide can be modified by the silane coupling agent. By adding silica into the silane coupling agent, silica and modified sepiolite can be connected by a carbon chain, thereby effectively improving the bonding force among modified sepiolite, graphene oxide and silica.

[0056] The preparation of the coating in this application will be further described in detail below in combination with specific embodiments.

[0057] Example 1

[0058] S1 Raw material preparation:

[0059] Prepare modified basalt fiber: Mix 100 ml of absolute ethanol and 10 ml of distilled water, then add 3 ml of KH550 coupling agent, react at 55 - 65 °C for 30 min, then add 0.06 - 0.08 g of nano-silica, stir at 50 - 55 °C for 1 h, then add 2.5 g of short-cut basalt fibers with a length of 2 - 6 mm, stir at 50 - 55 °C for 1 h, and then take out the fibers from the solution, and obtain the modified basalt fiber after drying;

[0060] Prepare modified nano-calcium carbonate: Mix 100 ml of absolute ethanol and 10 ml of distilled water, then add 3 - 5 ml of KH550 coupling agent, react at 50 - 55 °C for 30 min, then add 15 - 20 g of nano-silica, stir at 50 - 55 °C for 1 - 1.5 h, filter and dry to obtain the modified nano-calcium carbonate;

[0061] Prepare modified mica powder: Mix 100 ml of absolute ethanol and 10 ml of distilled water, then add 3 - 5 ml of KH550 coupling agent, react at 50 - 55 °C for 30 min, then add 15 - 20 g of mica powder, stir at 50 - 55 °C for 1 - 1.5 h, filter and dry to obtain the modified mica powder;

[0062] Prepare calcined sepiolite: Calcinate sepiolite at 400 - 430 °C for 2 h to obtain calcined sepiolite.

[0063] S2 10 parts of sepiolite and 5 times the mass of anhydrous ethanol of sepiolite are mixed, and then 9.5% of the mass of sepiolite KH550 coupling agent and 10% of the mass of KH550 deionized water are added, and refluxed and stirred at 40°C for 2 h, and then 8 parts of graphene oxide are added, and refluxed and stirred for 1.5 h, and then filtered, washed and dried, and then the dried product is added to a silica aqueous solution (7 parts of nano-silicon dioxide is dispersed in water, wherein the mass fraction of nano-silicon dioxide is 30%), refluxed and stirred at 40°C for 1.5 h, and then filtered, washed and dried to obtain a dried product;

[0064] S3 50 parts of waterborne epoxy resin (SZS600), 1 part of wetting dispersant (SHYT5000) and 20 parts of deionized water are mixed, and then 17 parts of modified calcium carbonate, 16 parts of modified mica powder, the dried material, 2 parts of modified basalt fiber and 5 parts of metal powder (nano Ni powder) are added to the mixture, and component A is obtained after sufficient dispersion.

[0065] Before coating, component A and 25 parts of component B (polyamide resin) were mixed, and after being evenly dispersed, they were applied to the surface of the substrate and cured at 100°C.

[0066] The obtained coating performance tests are as follows:

[0067] Adhesion (GB / T1720-79): Level 1;

[0068] Water resistance (GB / T 1733-1933): No abnormality after 550h;

[0069] Acid resistance (GB / T 9274-1988): No abnormality after 500h;

[0070] 150℃ neutral salt spray resistance: no blistering, no shedding, no rusting for 1000h;

[0071] Surface drying time: 22min;

[0072] Drying time: 105min;

[0073] Coating appearance: There are no obvious cracks, pores, etc. on the coating surface;

[0074] Dry film thickness of one coating (GB / T 9274-1988): ≥120μm.

[0075] Example 2

[0076] Compared with Example 1, the amount of each component in component A was adjusted, and the remaining steps were the same as Example 1.

[0077] The dosage of component A after adjustment is as follows:

[0078] 45 parts of waterborne epoxy resin, 0.9 part of wetting and dispersing agent, 13 parts of calcium carbonate, 20 parts of mica powder, 13 parts of modified sepiolite, 6.5 parts of graphene oxide, 3 parts of modified basalt fiber, 5 parts of nano-silica, 2.5 parts of metal powder and 25 parts of deionized water.

[0079] Before coating, mix component A with 23 parts of component B. After uniform dispersion, coat it on the surface of the substrate and cure at 100 °C.

[0080] The performance of the obtained coating was tested as follows:

[0081] Adhesion (GB / T1720-79): Grade 1;

[0082] Water resistance (GB / T 1733-1933): No abnormality after 550 h;

[0083] Acid resistance (GB / T 9274-1988): No abnormality after 500 h;

[0084] Neutral salt spray resistance at 150 °C: No blistering, no peeling, no rusting after 1200 h;

[0085] Surface drying time: 19 min;

[0086] Dry-to-touch time: 90 min;

[0087] Coating appearance: No obvious cracks, pores, etc. on the coating surface;

[0088] Dry film thickness of one-time coating (GB / T 9274-1988): ≥120 μm.

[0089] Example 3

[0090] Compared with Example 1, the dosages of each component in component A were adjusted, and the remaining steps were the same as those in Example 1.

[0091] The adjusted dosage of component A is as follows:

[0092] 43 parts of waterborne epoxy resin, 0.9 part of wetting and dispersing agent, 16 parts of calcium carbonate, 20 parts of mica powder, 12 parts of modified sepiolite, 8 parts of graphene oxide, 3.5 parts of modified basalt fiber, 5.5 parts of nano-silica, 3 parts of metal powder and 24 parts of deionized water.

[0093] Before coating, mix component A with 22 parts of component B (polyamide resin). After uniform dispersion, coat it on the surface of the substrate and cure at 100 °C.

[0094] The performance of the obtained coating was tested as follows:

[0095] Adhesion (GB / T1720-79): Grade 1;

[0096] Water resistance (GB / T 1733 - 1933): No abnormality after 550 h;

[0097] Acid resistance (GB / T 9274 - 1988): No abnormality after 500 h;

[0098] Neutral salt spray resistance at 150 °C: No blistering, no peeling, no rusting after 1250 h;

[0099] Surface drying time: 15 min;

[0100] Full drying time: 78 min;

[0101] Appearance of coating: No obvious cracks, pores, etc. on the coating surface;

[0102] Dry film thickness of single coating (GB / T 9274 - 1988): ≥120 μm.

[0103] Comparative Example 1

[0104] Compared with Example 1

[0105] Remove graphene oxide from Component A, and the other components and steps are the same as in Example 1.

[0106] Before coating the paint, mix Component A and 25 parts of Component B (polyamide resin). After uniform dispersion, coat it on the surface of the substrate and cure at 100 °C.

[0107] The performance test of the obtained coating is as follows:

[0108] Water resistance (GB / T 1733 - 1933): Peeling occurred after 300 h;

[0109] Acid resistance (GB / T 9274 - 1988): Peeling occurred after 330 h;

[0110] Neutral salt spray resistance at 150 °C: Blistering, peeling or rusting occurred after 680 h;

[0111] Comparative Example 2

[0112] Compared with Example 1, remove modified basalt fiber, and the other components and steps are the same as in Example 1.

[0113] Before coating the paint, mix Component A and 25 parts of Component B (polyamide resin). After uniform dispersion, coat it on the surface of the substrate and cure at 100 °C.

[0114] The performance test of the obtained coating is as follows:

[0115] Surface drying time: 47 min;

[0116] Full drying time: 3.2 h.

[0117] By comparing the coating properties in Examples 1-3 and Comparative Examples 1-2, the following conclusions can be drawn:

[0118] (1) Examples 1-3 strictly follow the components, dosages, and preparation methods in the present invention. The coatings prepared have relatively excellent adhesion, water resistance, acid resistance, and neutral salt spray resistance at 150°C. Therefore, the coatings in the present invention have a significant corrosion resistance effect. Further, the surface drying time of the coatings in the present invention is 15-22 min, and the through drying time is 78-105 min, significantly shortening the drying of the coatings, which can greatly reduce the phenomenon of sagging during the drying process of the coatings, thereby improving the uniformity of the coating.

[0119] (2) The coating in Comparative Example 1 does not add graphene oxide, which causes the modified sepiolite and silica in it to be difficult to disperse into the coating, resulting in relatively poor dispersion uniformity and bonding force between components of the coating. At the same time, due to the non-addition of graphene oxide, the proportional relationship between components is destroyed, resulting in a significant reduction in various properties during the corrosion resistance performance test.

[0120] (3) The coating in Comparative Example 2 does not add modified basalt fibers, resulting in a decrease in the diffusion rate of the solvent, and thus an extension of both the surface drying time and the through drying time, leading to the phenomenon of sagging during drying and affecting the uniformity of the coating.

[0121] The above is only the preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications, and environments, and can be changed within the scope conceived herein through the above teachings or the techniques or knowledge in related fields. And the changes and alterations made by those skilled in the art without departing from the spirit and scope of the present invention shall fall within the protection scope of the appended claims of the present invention.

Claims

1. A fast-drying thick paste waterborne epoxy two-component anticorrosive coating, characterized in that, It includes Component A and Component B. Component A includes the following components in parts by weight: 30 - 50 parts of waterborne epoxy resin, 0.3 - 1 part of wetting and dispersing agent, 5 - 20 parts of calcium carbonate, 15 - 30 parts of mica powder, 5 - 15 parts of modified sepiolite, 5 - 10 parts of graphene oxide, 2 - 5 parts of modified basalt fiber, 3 - 8 parts of nano-silica, and 2 - 5 parts of metal powder; The preparation method of the modified sepiolite is as follows: First, calcin the sepiolite, and then modify it with a silane coupling agent; The preparation method of the modified basalt fiber is as follows: Add basalt fiber into a nano-silica solution modified with a silane coupling agent, fully react, and then dry; The preparation method of Component A is as follows: S1. Mix a silane coupling agent and deionized water, then add the calcined sepiolite. After full reaction, add graphene oxide. After full reaction, filter, wash, and dry. Add the dried product into an aqueous nano-silica solution. After full reaction, filter, wash, and dry to obtain a dried product; S2. Mix waterborne epoxy resin, wetting and dispersing agent, and deionized water, then add calcium carbonate, mica powder, the dried product, modified basalt fiber, and metal powder to the mixture. After full dispersion, Component A is obtained; Component B includes a curing agent.

2. The fast-drying thick paste waterborne epoxy two-component anti-corrosion coating according to claim 1, characterized in that, Component A includes the following components in parts by weight: 35 - 45 parts of waterborne epoxy resin, 0.5 - 0.95 part of wetting and dispersing agent, 8 - 18 parts of calcium carbonate, 18 - 25 parts of mica powder, 8 - 13 parts of modified sepiolite, 6 - 9 parts of graphene oxide, 2.5 - 4 parts of modified basalt fiber, 4 - 7 parts of nano-silica, and 2.5 - 4.5 parts of metal powder.

3. A fast-drying thick paste waterborne epoxy two-component anticorrosive coating according to claim 1, characterized in that Component A includes the following components in parts by weight: 43 parts of waterborne epoxy resin, 0.9 part of wetting and dispersing agent, 16 parts of calcium carbonate, 20 parts of mica powder, 12 parts of modified sepiolite, 8 parts of graphene oxide, 3.5 parts of modified basalt fiber, 5.5 parts of nano-silica, and 3 parts of metal powder.

4. A quick-drying thick paste waterborne epoxy two-component anti-corrosion coating according to claim 1, characterized in that, The calcium carbonate is calcium carbonate modified with a silane coupling agent.

5. The fast-drying thick paste waterborne epoxy two-component anti-corrosion coating according to claim 1, characterized in that, The mica powder is mica powder modified with a silane coupling agent.

6. The quick-drying thick paste waterborne epoxy two-component anticorrosive coating according to claim 1, characterized in that, The metal powder is one or more of Cr, Ni, V, and Ti.

7. The preparation method of the quick-drying thick paste waterborne epoxy two-component anticorrosive coating according to any one of claims 1-6, characterized in that, The preparation method of Component A is as follows: S1. Mix a silane coupling agent and deionized water, then add the calcined sepiolite. After full reaction, add graphene oxide. After full reaction, filter, wash, and dry. Add the dried product into an aqueous nano-silica solution. After full reaction, filter, wash, and dry to obtain a dried product; S2. Mix waterborne epoxy resin, wetting and dispersing agent, and deionized water, then add calcium carbonate, mica powder, the dried product, modified basalt fiber, and metal powder to the mixture. After full dispersion, Component A is obtained.