Anticorrosive coating material, method for producing the same, and use thereof

Abstract

The application belongs to the field of chemical coating and relates to a kind of anticorrosive coating material and its preparation method and application. It includes: epoxy zinc-rich primer layer, epoxy cloud iron intermediate paint layer and composite coating topcoat layer; the epoxy zinc-rich primer layer is conductive modified epoxy zinc-rich primer, the conductive modified epoxy zinc-rich primer includes component A and component B, the component A includes the following components by weight fraction: epoxy resin 6-20 parts, solvent 2-10 parts, zinc powder 70-85 parts, conductive modifier 0.01-0.5 parts, accelerator 0.5-2 parts; the component B includes the following components by weight fraction: modified phenolic amine curing agent 40-60 parts, modified alicyclic amine curing agent 20-40 parts, solvent 10-30 parts; the mass ratio of the component A and component B is 5-20:1. The anticorrosive coating material of the application still reaches excellent level in various performance indicators after being used on the outer surface of large oil storage tank floating roof for 8 years.

Description

Technical Field

[0001] This invention belongs to the field of chemical coating, specifically relating to an anti-corrosion coating material, its preparation method, and its application. Background Technology

[0002] Based on the environment of the floating platform of the oil tank, its function is to isolate crude oil from the atmosphere, prevent the volatilization of light components in the crude oil, and reduce crude oil loss. As the crude oil level rises and falls, the platform deforms due to gravity, crude oil pressure, and the friction of the soft seals and the floating platform. For example, when the platform rises, the downward friction of the soft seals and gravity, combined with the pressure of the crude oil entering the tank, causes the platform to bulge upwards. When the platform descends, the upward friction of gravity and the soft seals creates a vacuum inside the tank, causing the platform to collapse downwards. This frequent up-and-down movement of the oil tank generates alternating stress on the platform, which can cause cracking and peeling of the anti-corrosion layer. Furthermore, the uneven outer surface of the platform can lead to electrochemical corrosion from long-term water accumulation in the depressions, resulting in continuous pitting corrosion, which can even cause perforation in severe cases.

[0003] As crucial containers for storing oil products, oil storage tanks are frequently subjected to corrosion from both internal and external environmental media during long-term use. Externally, they are constantly exposed to the natural environment, suffering from atmospheric corrosion, acid rain, and other corrosive agents. If oil storage tanks are not promptly protected against corrosion or if inadequate measures are taken, serious leaks can occur, affecting oil usage and polluting the environment. Therefore, whether it's external or internal corrosion, prolonged corrosion will eventually lead to equipment damage and scrapping, and in severe cases, safety accidents. Thus, strengthening corrosion protection measures for oil storage tanks cannot be ignored.

[0004] The top of a floating roof tank is subject to erosion from the atmosphere, rainwater, and sunlight, resulting in varying degrees of corrosion. Water vapor can dissolve nitrogen oxides and sulfides in the air, forming an electrolyte solution on the tank top, which may even remain submerged for extended periods. Under these conditions, iron oxides on the tank top further oxidize ferrous iron to ferric iron, forming a loose rust layer that adheres to the surface. Simultaneously, the oxygen and water on the tank surface, along with the rust layer and the tank wall, form an oxygen concentration cell, further exacerbating corrosion of the tank top. Stress deformation occurs during the welding and assembly process of the floating roof tank top, resulting in pits and depressions. In rainy and humid environments, water continuously exists in these pits, forming an electrochemical corrosion system with oxygen in the air, accelerating corrosion of the tank top. Furthermore, the tank top's prolonged exposure to sunlight and alternating hot and cold environments causes expansion and contraction of the coating, generating stress.

[0005] Electrochemical corrosion of storage tank exteriors is generally severe in humid and hot environments. Therefore, anti-corrosion coatings that combine weather resistance, water resistance, heat resistance, oil resistance, corrosion resistance, resistance to damp heat, high temperature, and acid rain resistance should be selected. Furthermore, for inland surface storage tanks, the impact of atmospheric acidity corrosion should be considered, while for coastal surface storage tanks, the impact of atmospheric salinity should also be taken into account. Currently, the anti-corrosion coating for the outer surface of large oil storage tank floating roofs uses a composite coating scheme consisting of an epoxy zinc-rich primer layer, an epoxy micaceous iron oxide anti-corrosion coating intermediate layer, and an acrylic polyurethane anti-corrosion coating or fluorocarbon anti-corrosion coating topcoat. However, due to an unreasonable anti-corrosion system for the tank roof exterior, after a period of use, the metal corrosion product Fe2O3 is clearly visible to the naked eye. This indicates poor rust prevention performance of the underlying layer or insufficient primer thickness, an excessively thin intermediate coating with inadequate isolation of corrosive media, and poor UV resistance and waterproofing of the topcoat, leading to large-area electrochemical corrosion in a short period. Currently, conventional epoxy coatings have poor flexibility and are prone to cracking on the surface of floating roofs under certain stress, which leads to paint film failure and affects the anti-corrosion effect of the coating. The protection time of the coating is generally 2 to 3 years before it fails.

[0006] Furthermore, conventional epoxy zinc-rich primers suffer from problems such as low volumetric solids content, high VOC emissions, environmental unfriendliness, poor adhesion, and low zinc powder utilization. Studies have shown that only 25%–35% of the zinc powder in epoxy zinc-rich primers plays a role in cathodic protection. In the initial stage of coating protection, the epoxy zinc-rich primer primarily functions as a cathodic protectant. After immersion in corrosive media for 168 hours, some zinc powder is oxidized into non-conductive zinc salts, weakening the inter-particle connectivity and affecting the utilization efficiency of the zinc powder. At this point, the coating protection primarily functions as a shield. Therefore, how to reduce the zinc content and improve the utilization rate of zinc powder while ensuring the excellent anti-corrosion performance of epoxy zinc-rich primers is of significant research importance and market value. Summary of the Invention

[0007] The purpose of this invention is to solve the above-mentioned problems existing in the prior art and to provide an anti-corrosion coating material and its preparation method. The coating material has the characteristics of high solids content, environmental friendliness, excellent adhesion, strong corrosion resistance, and excellent weather resistance. It can be used as an anti-corrosion coating on the outer surface of the floating roof of large oil storage tanks, and all performance indicators of the coating have reached excellent levels.

[0008] To achieve the above objectives, a first aspect of the present invention provides an anti-corrosion coating material, comprising: an epoxy zinc-rich primer layer, an epoxy micaceous iron oxide intermediate paint layer, and a composite coating topcoat layer.

[0009] The epoxy zinc-rich primer layer is a conductive modified epoxy zinc-rich primer, which includes component A and component B. Component A includes the following components by weight: 6-20 parts epoxy resin, preferably 8-15 parts; 2-10 parts solvent, preferably 3-5 parts; 70-85 parts zinc powder, preferably 80-82 parts; 0.01-0.5 parts conductive modifier, preferably 0.01-0.4 parts; and 0.5-2 parts accelerator, preferably 0.5-1.5 parts. Component B includes the following components by weight: 40-60 parts modified phenolic amine curing agent, preferably 45-60 parts; 20-40 parts modified alicyclic amine curing agent, preferably 20-30 parts; and 10-30 parts solvent, preferably 15-25 parts. The mass ratio of component A to component B is 5-20:1.

[0010] A second aspect of the present invention provides a method for preparing the aforementioned anti-corrosion coating material, comprising the following steps:

[0011] The preparation method of conductive modified epoxy zinc-rich primer is as follows:

[0012] Preparation of component A:

[0013] ① Mix the epoxy resin and solvent, stirring at low speed;

[0014] ② Add conductive modifier and optional thixotropic agent, optional dispersant, optional defoamer, and stir at medium speed to disperse;

[0015] ③ Add zinc powder, disperse at medium speed, and control the temperature at 40-45℃;

[0016] ④ Cool down to 25-30℃, control the slurry fineness ≤60μm, add accelerator, stir evenly, and obtain component A;

[0017] Preparation of component B: Modified phenolic amine curing agent, modified alicyclic amine curing agent and solvent are mixed by stirring at medium speed to obtain component B;

[0018] Component A and component B are mixed to obtain the conductive modified epoxy zinc-rich primer.

[0019] A third aspect of the present invention provides the application of the aforementioned anti-corrosion coating material as an anti-corrosion coating on the outer surface of the floating roof of an oil storage tank.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) The conductive modified epoxy zinc-rich primer of the present invention has the characteristics of high volume solids content, low VOC emission, environmental friendliness, excellent adhesion and high zinc powder utilization.

[0022] (2) Furthermore, the fiber-modified epoxy micaceous iron oxide intermediate paint of the present invention has the characteristics of high volume solids content and excellent adhesion, flexibility and corrosion resistance.

[0023] (3) Furthermore, the fluorine-modified composite coating topcoat of the present invention has the characteristics of high volume solids content, good weather resistance, and excellent chemical resistance.

[0024] (4) The conductive modified epoxy zinc-rich primer, fiber modified epoxy micaceous iron oxide intermediate paint and fluorine modified composite coating topcoat of the present invention are used as anti-corrosion coatings on the outer surface of floating roofs of large oil storage tanks. Specifically, they have excellent adhesion, water resistance, chemical resistance and weather resistance. After being used on the outer surface of floating roofs of large oil storage tanks for 8 years, the performance indicators of the coating still reach excellent levels.

[0025] Other features and advantages of the present invention will be described in detail in the following detailed description section. Detailed Implementation

[0026] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0027] To achieve the above objectives, a first aspect of the present invention provides an anti-corrosion coating material, comprising: an epoxy zinc-rich primer layer, an epoxy micaceous iron oxide intermediate paint layer, and a composite coating topcoat layer.

[0028] The epoxy zinc-rich primer layer is a conductive modified epoxy zinc-rich primer, which includes component A and component B. Component A includes the following components by weight: 6-20 parts epoxy resin, preferably 8-15 parts; 2-10 parts solvent, preferably 3-5 parts; 70-85 parts zinc powder, preferably 80-82 parts; 0.01-0.5 parts conductive modifier, preferably 0.01-0.4 parts; and 0.5-2 parts accelerator, preferably 0.5-1.5 parts. Component B includes the following components by weight: 40-60 parts modified phenolic amine curing agent, preferably 45-60 parts; 20-40 parts modified alicyclic amine curing agent, preferably 20-30 parts; and 10-30 parts solvent, preferably 15-25 parts. The mass ratio of component A to component B is 5-20:1.

[0029] In this invention, the anti-corrosion mechanism of epoxy zinc-rich primer is as follows: Epoxy zinc-rich primer, as a commonly used heavy-duty anti-corrosion coating, is widely used due to its excellent physical and mechanical properties and anti-corrosion performance. Its anti-corrosion mechanism mainly utilizes the fact that the activity of elemental zinc powder is greater than that of iron, achieving the purpose of sacrificial anode and providing cathodic protection for metal substrates such as steel. At the same time, the corrosion products such as zinc oxide and zinc hydroxide produced by the oxidation of zinc powder can fill the defects after the coating is damaged and form a shielding layer, playing a role in self-repair and preventing the intrusion of corrosive media. By adding graphene conductive powder, on the one hand, it forms a nano-network structure in the coating, enhancing the physical barrier effect of the coating and providing extremely strong anti-corrosion performance; on the other hand, it can improve the utilization rate of zinc powder and greatly improve the anti-corrosion performance of the paint film.

[0030] According to the present invention, preferably, component A further includes at least one selected from 0.1 to 5 parts of a thixotropic agent, 0.1 to 5 parts of a dispersant, and 0.1 to 5 parts of a defoamer.

[0031] Preferably, in component A, the epoxy resin is a low-viscosity epoxy resin, preferably at least one of liquid epoxy resins DER354, DK-175×90, and 618; the conductive agent is a single-arm or multi-arm carbon nanotube, preferably a single-arm carbon nanotube, more preferably a single-arm carbon nanotube with a particle size <0.01μm; the zinc powder has a mesh size of 800-1200 mesh; and the accelerator is a polysiloxane adhesion promoter, preferably at least one selected from A-187 and / or 1121.

[0032] Preferably, in component B, the modified phenolic amine curing agent is selected from at least one of MD650, MD531E and NX-6003; the modified alicyclic amine curing agent is curing agent 3300 and / or curing agent 6280.

[0033] Preferably, the solvents in components A and B are each independently a diol ester compound and / or a polyester compound, preferably selected from PMA and / or DBE.

[0034] Preferably, the thixotropic agent is selected from at least one of organic bentonite 140, bentonite 979, polyamide wax powder HX-9110, fumed silica A200, and polyethylene wax paste 202P; the dispersant is selected from at least one of BYK-161, TOL-501, and ATU; and the defoamer is selected from at least one of BYK-066N, Tech-367, and NYK-052.

[0035] According to the present invention, preferably, the epoxy micaceous iron oxide intermediate varnish is a fiber-modified epoxy micaceous iron oxide intermediate varnish, which comprises component C and component D. Component C comprises the following components by weight: 10-40 parts epoxy resin, preferably 15-35 parts; 2-20 parts solvent, preferably 3-10 parts; 1-6 parts reactive diluent, preferably 2-5 parts; 1-10 parts fiber film-forming aid, preferably 1-8 parts; and micaceous iron oxide. The components are: 5-25 parts, preferably 10-20 parts; filler: 10-50 parts, preferably 30-40 parts; pigment: 1-20 parts, preferably 10-18 parts; component D includes the following components by weight: 30-70 parts of polyamide curing agent, preferably 40-60 parts; fatty amine curing agent: 10-40 parts, preferably 10-20 parts; solvent: 5-20 parts, preferably 10-20 parts; the mass ratio of component C to component D is 6-20:1.

[0036] In this invention, the volume solids content is increased by selecting a suitable pigment-to-binder ratio and a co-solvent system, and the flexibility of the intermediate coating film is improved by selecting fiber-modified materials.

[0037] According to the present invention, preferably, component C further includes at least one selected from 0.1 to 5 parts of a thixotropic agent, 0.1 to 5 parts of a dispersant, and 0.1 to 5 parts of a defoamer.

[0038] Preferably, in component C, the epoxy resin is a low-viscosity bisphenol A epoxy resin, preferably at least one of liquid epoxy resins E51, E44, and E20; the reactive diluent is selected from at least one of AGE, BGE, and PLA602; the fiber film-forming aid is hydroxyethyl cellulose; the mica iron oxide has a mesh size of 400-800 mesh; the filler is selected from at least one of modified barium sulfate, talc powder, and mica powder, preferably modified barium sulfate with a mesh size of 1000-1500 mesh; and the pigment is selected from titanium dioxide and / or carbon black.

[0039] Preferably, in component D, the polyamide curing agent is selected from at least one of Miki 650, D8115 and V115; and the fatty amine curing agent is selected from at least one of Miki 593, Aradur 943 and 2636.

[0040] Preferably, the solvents in components C and D are each independently a diol ester compound and / or a polyester compound, preferably selected from PMA and / or DBE.

[0041] Preferably, the thixotropic agent is selected from at least one of organic bentonite 140, bentonite 979, polyamide wax powder HX-9110, fumed silica A200, and polyethylene wax paste 202P; the dispersant is selected from at least one of BYK-161, TOL-501, and ATU; and the defoamer is selected from at least one of BYK-066N, Tech-367, and NYK-052.

[0042] According to the present invention, preferably, the composite coating topcoat layer is a fluorine-modified composite coating topcoat, which includes component E and component F. Component E includes the following components by weight: 30-60 parts of hydroxypropyl resin, preferably 40-60 parts; 2-15 parts of solvent, preferably 2-10 parts; 1-15 parts of fluorine-containing functional powder, preferably 2-8 parts; 5-35 parts of filler, preferably 10-30 parts; 10-40 parts of pigment, preferably 15-30 parts; 0.1-5 parts of ultraviolet light absorber, preferably 0.5-1.5 parts; and 0.1-5 parts of light stabilizer, preferably 0.5-2 parts. Component F includes the following components by weight: 60-90 parts of HDI trimer curing agent, preferably 70-80 parts; and 10-40 parts of solvent, preferably 20-30 parts. The mass ratio of component E to component F is 4-15:1.

[0043] In this invention, by selecting a specific modified resin system and combining it with a specific HDI curing agent and crosslinking density, the aging resistance and media resistance of the topcoat are further improved, and the volume solids content is increased by selecting a suitable pigment-to-binder ratio and co-solvent system.

[0044] According to the present invention, preferably, the E component further includes at least one selected from 0.1 to 5 parts of a thixotropic agent, 0.1 to 5 parts of a dispersant, and 0.1 to 5 parts of a defoamer.

[0045] Preferably, in component E, the hydroxypropyl resin is selected from at least one of LR-7765, SM513 / 60LG, and FX-9070; the fluorinated functional powder is 800-1200 mesh polytetrafluoroethylene powder; the filler is 800-1200 mesh modified ultrafine barium sulfate; the pigment is selected from titanium dioxide and / or carbon black; the ultraviolet light absorber is 2-(2H-benzotriazol-2-yl)-4,6-di-tert-amylphenol; and the light stabilizer is mono(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate.

[0046] Preferably, in component F, the HDI trimer curing agent is HT100 and / or N3390.

[0047] Preferably, the solvents in components E and F are each independently a diol ester compound and / or a polyester compound, preferably selected from PMA and / or DBE.

[0048] Preferably, the thixotropic agent is selected from at least one of organic bentonite 140, bentonite 979, polyamide wax powder HX-9110, fumed silica A200, and polyethylene wax paste 202P; the dispersant is selected from at least one of BYK-161, TOL-501, and ATU; and the defoamer is selected from at least one of BYK-066N, Tech-367, and NYK-052.

[0049] In this invention, DK-175×90 was purchased from Guodu Chemical Company, 618 was purchased from Nanya Electronic Materials Company, A-187 was purchased from Jiangsu Chenguang Company, and 1121 was purchased from Haiming Sideqian Company.

[0050] In this invention, MD650 and MD531E were purchased from Anhui Meidong Company, NX-6003 was purchased from Cardlä Company, curing agent 3300 was purchased from Rich Chemical Company, and curing agent 6280 was purchased from Shanghai Junjiang Company.

[0051] In this invention, E51 was purchased from Nan Ya Electronic Materials Co., Ltd., E44 was purchased from Nan Ya Electronic Materials Co., Ltd., E20 was purchased from Nan Ya Electronic Materials Co., Ltd., AGE was purchased from Jiangsu Sanmu Co., Ltd., BGE was purchased from Jiangsu Sanmu Co., Ltd., and PLA602 was purchased from Shanghai Dekun Co., Ltd.

[0052] In this invention, Sanmu 650 was purchased from Jiangsu Sanmu Company, D8115 from Shanghai Junjiang Company, V115 from Jiadida Chemical Company, 593 from Jiangsu Sanmu Company, Aradur 943 from Huntsman Company, and 2636 from Shanghai Dekun Company.

[0053] In this invention, LR-7765 was purchased from Mitsubishi Corporation of Japan, SM513 / 60LG was purchased from Zhanxin Resin Company, and FX-9070 was purchased from Nantong Fangxin Chemical Company.

[0054] In this invention, HT100 was purchased from Wanhua Chemical Company and N3390 was purchased from Covestro Company.

[0055] A second aspect of the present invention provides a method for preparing the aforementioned anti-corrosion coating material, comprising the following steps:

[0056] The preparation method of conductive modified epoxy zinc-rich primer is as follows:

[0057] Preparation of component A:

[0058] ① Mix the epoxy resin and solvent, stirring at low speed;

[0059] ② Add conductive modifier and optional thixotropic agent, optional dispersant, optional defoamer, and stir at medium speed to disperse;

[0060] ③ Add flaky zinc powder, disperse at medium speed, and control the temperature at 40-45℃;

[0061] ④ Cool down to 25-30℃, control the slurry fineness ≤60μm, add accelerator, stir evenly, and obtain component A;

[0062] Preparation of component B: Modified phenolic amine curing agent, modified alicyclic amine curing agent and solvent are mixed by stirring at medium speed to obtain component B;

[0063] Component A and component B are mixed to obtain the conductive modified epoxy zinc-rich primer.

[0064] Preferably, the low-speed stirring conditions include a speed of 400-600 r / min and a time of 5-40 min; the medium-speed stirring conditions include a speed of 700-800 r / min and a time of 5-40 min.

[0065] According to the present invention, preferably, it further includes the preparation steps of fiber-modified epoxy micaceous iron oxide intermediate paint and fluorine-modified composite coating topcoat;

[0066] The preparation method of fiber-modified epoxy micaceous iron oxide intermediate varnish is as follows:

[0067] Preparation of component C:

[0068] ① Mix epoxy resin, reactive diluent and solvent, stirring at low speed;

[0069] ② Add fiber film-forming aids and optional thixotropic agents, optional dispersants, and optional defoamers, and disperse by high-speed stirring;

[0070] ③ Add flaky mica iron oxide, filler and pigment, stir and disperse at high speed, and control the temperature at 40-45℃;

[0071] ④ Cool down to 25-30℃, control the slurry fineness to ≤60μm, and obtain the C component;

[0072] Preparation of component D: Polyamide curing agent, fatty amine curing agent and solvent are mixed by stirring at medium speed to obtain component D;

[0073] Components C and D are mixed to obtain fiber-modified epoxy micaceous iron oxide intermediate paint;

[0074] The preparation method of fluorine-modified composite coating topcoat is as follows:

[0075] Preparation of component E:

[0076] ① Mix hydroxypropyl resin and solvent, stirring at low speed;

[0077] ② Add optional thixotropic agent, optional dispersant, and optional defoamer, and disperse by high-speed stirring;

[0078] ③ Add fluorine-containing functional powders, fillers and pigments, and stir and disperse them at high speed, controlling the temperature at 40-45℃;

[0079] ④ Cool down to 25-30℃ and control the slurry fineness to ≤30μm;

[0080] ⑤ Add ultraviolet light absorber and light stabilizer, stir and disperse at medium speed to obtain component E;

[0081] Preparation of component F: HDI trimer curing agent and solvent are dispersed by medium-speed stirring to obtain component F;

[0082] Components E and F are mixed to obtain the fluorine-modified composite coating topcoat.

[0083] According to the present invention, preferably, the low-speed stirring conditions include: a speed of 400-600 r / min and a time of 5-40 min; the medium-speed stirring conditions include: a speed of 700-800 r / min and a time of 5-40 min; and the high-speed stirring conditions include: a speed of 1000-1100 r / min and a time of 5-40 min.

[0084] A third aspect of the present invention provides the application of the aforementioned anti-corrosion coating material as an anti-corrosion coating on the outer surface of the floating roof of an oil storage tank.

[0085] According to the present invention, preferably, the thickness of the conductive modified epoxy zinc-rich primer layer is 80-100 μm; the thickness of the fiber modified epoxy micaceous iron oxide intermediate paint layer is 120-160 μm; and the thickness of the fluorine modified composite coating topcoat layer is 80-100 μm.

[0086] The raw materials used in the embodiments of this invention are all commercially available.

[0087] Example 1

[0088] (I) The preparation method of conductive modified epoxy zinc-rich primer is as follows:

[0089] Preparation of Component A:

[0090] ① Stir 11 parts of liquid epoxy resin DER 354 and 4.9 parts of propylene glycol methyl ether acetate solvent at a speed of 400-600 r / min for 12 min;

[0091] ② Add 1 part HX-9110 thixotropic agent and 0.1 part single-arm carbon nanotubes, and disperse at a speed of 600-800 r / min for 12 min;

[0092] ③ Add 82 parts of 1200 mesh zinc powder and disperse at a speed of 600-800 r / min for 30 min, while controlling the temperature at 40-45℃;

[0093] ④ Cool down to 25-30℃, add 1 part of A-187, stir evenly, and then grind the slurry in a sand mill until the fineness is ≤60μm to obtain component A.

[0094] Preparation of Component B: 60 parts of NX-6003 phenolic amine curing agent, 20 parts of 6280 alicyclic amine curing agent and 20 parts of propylene glycol methyl ether acetate solvent were dispersed at a speed of 600-800 r / min for 20 min to obtain Component B.

[0095] Component A and component B were mixed at a mass ratio of 12:1 to obtain the conductive modified epoxy zinc-rich primer, and its performance test results are shown in Table 1.

[0096] (II) The preparation method of fiber-modified epoxy micaceous iron oxide intermediate varnish is as follows:

[0097] Preparation of component C:

[0098] ① Mix 20 parts of liquid epoxy resin E51, 2 parts of cashew phenol glycidyl ether and 8.5 parts of propylene glycol methyl ether acetate evenly, and stir at 400-600 r / min for 20 min.

[0099] ② Add 1.5 parts of HX-9110 thixotropic agent and 5 parts of hydroxyethyl cellulose, and disperse at a speed of 1000-1100 r / min for 20 min;

[0100] ③ Add 15 parts of 800-mesh flaky mica iron oxide, 15 parts of rutile titanium dioxide and 33 parts of 1250-mesh ultrafine modified barium sulfate, disperse at a speed of 1000-1100 r / min for 30 min, and control the temperature at 40-45℃.

[0101] ④ Cool down to 25-30℃, control the slurry fineness to ≤60μm, and obtain the C component;

[0102] Preparation of component D: 60 parts of D8115 polyamide curing agent, 20 parts of 2636 fatty amine curing agent, 20 parts of propylene glycol methyl ether acetate, and 20 parts of DBE solvent were dispersed at a speed of 600-800 r / min for 20 min to obtain component D.

[0103] Components C and D were mixed at a mass ratio of 10:1 to obtain fiber-modified epoxy micaceous iron oxide intermediate paint, and its performance test results are shown in Table 2.

[0104] (III) The preparation method of fluorine-modified composite coating topcoat is as follows:

[0105] Preparation of component E:

[0106] ① Mix 50 parts of LR-7765, 2 parts of propylene glycol methyl ether acetate and 1 part of DBE solvent evenly, and stir at 400-600 r / min for 12 min;

[0107] ② Add 1 part of 140 bentonite and 0.5 parts of A200 fumed silica thixotropic agent, at a concentration of 1000~

[0108] Disperse at a speed of 1100 r / min for 12 min;

[0109] ③ Add 5.5 parts of 1250-mesh ultrafine polytetrafluoroethylene powder, 18 parts of 1250-mesh ultrafine modified barium sulfate, and 20 parts of rutile titanium dioxide, and disperse at a speed of 1000-1100 r / min for 30 min.

[0110] The temperature should be controlled at 40–45℃;

[0111] ④ Cool down to 25-30℃, and then grind the slurry in a sand mill until the fineness is ≤30μm;

[0112] ⑤ Add 1.5 parts of 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol and 1.5 parts of mono(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, and disperse at 600-800 r / min for 12 min to obtain component E.

[0113] Preparation of component F: 80 parts of aliphatic polyisocyanate N3390 and 20 parts of propylene glycol methyl ether acetate were dispersed at a speed of 600-800 r / min for 20 min to obtain component F.

[0114] Components E and F were mixed at a mass ratio of 6:1 to obtain the fluorine-modified composite coating topcoat, and its performance test results are shown in Table 3.

[0115] Table 1

[0116]

[0117]

[0118] Table 2

[0119]

[0120]

[0121] Note: The coating thickness for testing resistance to hot water, gasoline, salt spray, and chemical media is 125μm to 160μm.

[0122] Table 3

[0123]

[0124]

[0125] Note: The coating system and thickness for testing adhesion, gasoline resistance, salt spray resistance, chemical resistance, artificial accelerated aging, and freeze-thaw cycles should be determined according to the technical documents or design documents provided by the coating supplier. Environmentally friendly graphene epoxy zinc-rich primer / environmentally friendly graphene rust-resistant primer: 80μm~100μm; environmentally friendly fiber-modified epoxy micaceous iron oxide intermediate paint: 120μm~160μm; fluorine-modified high-solids composite topcoat: 80μm~100μm. Total film thickness: 280μm~340μm.

[0126] Example 2

[0127] In this embodiment, the only difference between component A and that in Example 1 is that the single-arm carbon nanotube is 0.3 parts, resulting in the conductive modified epoxy zinc-rich primer. Its performance test results are shown in Table 4.

[0128] Table 4

[0129]

[0130]

[0131] In this embodiment, the only difference between component C and Example 1 is that the amount of hydroxyethyl cellulose is 9 parts. The fiber-modified epoxy micaceous iron oxide intermediate varnish was obtained, and its performance tests are shown in Table 5.

[0132] Table 5

[0133]

[0134]

[0135] Note: The coating thickness for testing resistance to hot water, gasoline, salt spray, and chemical media is 125μm to 160μm.

[0136] In this embodiment, the only difference between component E and that in Example 1 is that 7 parts of 1250-mesh ultrafine polytetrafluoroethylene powder are used. The performance test results of the obtained fluorine-modified composite coating topcoat are shown in Table 6.

[0137] Table 6

[0138]

[0139]

[0140] Example 3

[0141] The only difference between this embodiment and Embodiment 1 is that the single-arm carbon nanotubes in the conductive modified epoxy zinc-rich primer are replaced with graphene.

[0142] The conductive modified epoxy zinc-rich primer was obtained, and its performance test results are shown in Table 7:

[0143] Table 7

[0144]

[0145]

[0146] Example 4

[0147] The only difference between this embodiment and Embodiment 1 is that the epoxy resin in the fiber-modified epoxy micaceous iron oxide intermediate varnish is replaced with E20.

[0148] The fiber-modified epoxy micaceous iron oxide intermediate paint obtained is shown in Table 8.

[0149] Table 8

[0150]

[0151]

[0152] Note: The coating thickness for testing resistance to hot water, gasoline, salt spray, and chemical media is 125μm to 160μm.

[0153] Example 5

[0154] The only difference between this embodiment and Embodiment 1 is that the resin LR7765 in the fluorine-modified composite coating topcoat is replaced with Fangxin FX-9070.

[0155] The performance of the obtained fluorine-modified composite coating topcoat is shown in Table 9.

[0156] Table 9

[0157]

[0158]

[0159] Note: The coating system and thickness for testing adhesion, gasoline resistance, salt spray resistance, chemical resistance, artificial accelerated aging, and freeze-thaw cycles should be determined according to the technical documents or design documents provided by the coating supplier. Environmentally friendly graphene epoxy zinc-rich primer / environmentally friendly graphene rust-resistant primer: 80μm~100μm; environmentally friendly fiber-modified epoxy micaceous iron oxide intermediate paint: 120μm~160μm; fluorine-modified high-solids composite topcoat: 80μm~100μm. Total film thickness: 280μm~340μm.

[0160] Example 6

[0161] The only difference from Example 1 is that the curing agent NX6003 in the conductive modified epoxy zinc-rich primer is replaced with MD531E.

[0162] The conductive modified epoxy zinc-rich primer was obtained, and its performance tests are shown in Table 10:

[0163] Table 10

[0164]

[0165]

[0166] Example 7

[0167] The only difference from Example 1 is that the curing agent 2778 in the fiber-modified epoxy micaceous iron oxide intermediate paint is replaced with Miki 650.

[0168] The fiber-modified epoxy micaceous iron oxide intermediate paint obtained is shown in Table 11.

[0169] Table 11

[0170]

[0171]

[0172] Note: The coating thickness for testing resistance to hot water, gasoline, salt spray, and chemical media is 125μm to 160μm.

[0173] Example 8

[0174] The only difference from Example 1 is that the isocyanate curing agent in the fluorine-modified composite coating topcoat is replaced with HT100.

[0175] The performance of the obtained fluorine-modified composite coating topcoat is shown in Table 12.

[0176] Table 12

[0177]

[0178]

[0179] Note: The coating system and thickness for testing adhesion, gasoline resistance, salt spray resistance, chemical resistance, artificial accelerated aging, and freeze-thaw cycles should be determined according to the technical documents or design documents provided by the coating supplier. Environmentally friendly graphene epoxy zinc-rich primer / environmentally friendly graphene rust-resistant primer: 80μm~100μm; environmentally friendly fiber-modified epoxy micaceous iron oxide intermediate paint: 120μm~160μm; fluorine-modified high-solids composite topcoat: 80μm~100μm. Total film thickness: 280μm~340μm.

[0180] Comparative Example 1

[0181] The only difference between this comparative example and Example 1 is that single-arm carbon nanotubes were not added to component A, hydroxyethyl cellulose was not added to component C, and 1250-mesh ultrafine polytetrafluoroethylene powder was not added to component E. The performance tests of the obtained primer, intermediate coat, and topcoat are shown in Tables 13, 14, and 15, respectively.

[0182] Table 13

[0183]

[0184]

[0185] Table 14

[0186]

[0187]

[0188] Note: The coating thickness for testing resistance to hot water, gasoline, salt spray, and chemical media is 125μm to 160μm.

[0189] Table 15

[0190]

[0191]

[0192] Note: The coating system and thickness for testing adhesion, gasoline resistance, salt spray resistance, chemical resistance, artificial accelerated aging, and freeze-thaw cycles should be determined according to the technical documents or design documents provided by the coating supplier. Environmentally friendly epoxy zinc-rich primer / rust-resistant primer: 80μm~100μm; epoxy micaceous iron oxide intermediate coat: 120μm~160μm; high-solids composite topcoat: 80μm~100μm. Total film thickness: 280μm~340μm.

[0193] Application Example 1

[0194] The primer, intermediate coat, and topcoat of Example 1 were used as anti-corrosion coatings on the outer surface of the floating roof of a large oil storage tank, with thicknesses of 80–100 μm, 160–180 μm, and 80–100 μm, respectively. After 8 years, no metal corrosion product Fe2O3 was observed.

[0195] Application Example 2

[0196] The primer, intermediate coat, and topcoat of Comparative Example 1 were used as anti-corrosion coatings on the outer surface of the floating roof of a large oil storage tank, with thicknesses of 80–100 μm, 160–180 μm, and 80–100 μm, respectively. After 2 years, severe corrosion occurred.

[0197] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. An anti-corrosion coating material, characterized in that, include: Epoxy zinc-rich primer, epoxy micaceous iron oxide intermediate coat, and composite coating topcoat; The epoxy zinc-rich primer layer is a conductive modified epoxy zinc-rich primer, which includes component A and component B. Component A includes the following components by weight: 6-20 parts epoxy resin, preferably 8-15 parts; 2-10 parts solvent, preferably 3-5 parts; 70-85 parts zinc powder, preferably 80-82 parts; 0.01-0.5 parts conductive modifier, preferably 0.01-0.4 parts; and 0.5-2 parts accelerator, preferably 0.5-1.5 parts. Component B includes the following components by weight: 40-60 parts modified phenolic amine curing agent, preferably 45-60 parts; 20-40 parts modified alicyclic amine curing agent, preferably 20-30 parts; and 10-30 parts solvent, preferably 15-25 parts. The mass ratio of component A to component B is 5-20:

1.

2. The anti-corrosion coating material according to claim 1, wherein, Component A further includes at least one of the following: 0.1-5 parts of a thixotropic agent, 0.1-5 parts of a dispersant, and 0.1-5 parts of a defoamer; In component A, the epoxy resin is a low-viscosity epoxy resin, preferably at least one of liquid epoxy resins DER 354, DK-175×90 and 618; The conductive agent is a single-arm or multi-arm carbon nanotube, preferably a single-arm carbon nanotube, and more preferably a single-arm carbon nanotube with a particle size of <0.01μm. The zinc powder has a mesh size of 800-1200 mesh; The accelerator is a polysiloxane adhesion accelerator, preferably selected from at least one of A-187 and / or 1121; In component B, the modified phenolic amine curing agent is selected from at least one of MD650, MD531E and NX-6003; The modified alicyclic amine curing agent is curing agent 3300 and / or curing agent 6280; The solvents in components A and B are each independently diol esters and / or polyesters, preferably selected from PMA and / or DBE; The thixotropic agent is selected from at least one of organic bentonite 140, bentonite 979, polyamide wax powder HX-9110, fumed silica A200 and polyethylene wax paste 202P. The dispersant is selected from at least one of BYK-161, TOL-501 and ATU; The defoamer is selected from at least one of BYK-066N, Tech-367 and NYK-052.

3. The anti-corrosion coating material according to claim 1, wherein, The epoxy micaceous iron oxide intermediate coating is a fiber-modified epoxy micaceous iron oxide intermediate coating, which includes component C and component D. Component C includes the following components by weight: 10-40 parts epoxy resin, preferably 15-35 parts; 2-20 parts solvent, preferably 3-10 parts; 1-6 parts reactive diluent, preferably 2-5 parts; 1-10 parts fiber film-forming aid, preferably 1-8 parts; 5-25 parts micaceous iron oxide, preferably 10-20 parts; 10-50 parts filler, preferably 30-40 parts; and 1-20 parts pigment, preferably 10-18 parts. Component D includes the following components by weight: 30-70 parts polyamide curing agent, preferably 40-60 parts; 10-40 parts fatty amine curing agent, preferably 10-20 parts; and 5-20 parts solvent, preferably 10-20 parts. The mass ratio of component C to component D is 6-20:

1.

4. The anti-corrosion coating material according to claim 3, wherein, The C component further includes at least one selected from 0.1 to 5 parts of a thixotropic agent, 0.1 to 5 parts of a dispersant, and 0.1 to 5 parts of an antifoaming agent; In component C, the epoxy resin is a low-viscosity bisphenol A epoxy resin, preferably at least one of liquid epoxy resins E51, E44 and E20; The reactive diluent is selected from at least one of AGE, BGE and PLA602; The fiber film-forming aid is hydroxyethyl cellulose; The mica iron oxide has a mesh size of 400-800 mesh; The filler is selected from at least one of modified barium sulfate, talc powder and mica powder, preferably modified barium sulfate of 1000-1500 mesh; The pigment is selected from titanium dioxide and / or carbon black; In component D, the polyamide curing agent is selected from at least one of Miki 650, D8115 and V115; The fatty amine curing agent is selected from at least one of Miki 593, Aradur 943 and 2636; The solvents in components C and D are each independently diol esters and / or polyesters, preferably selected from PMA and / or DBE; The thixotropic agent is selected from at least one of organic bentonite 140, bentonite 979, polyamide wax powder HX-9110, fumed silica A200 and polyethylene wax paste 202P. The dispersant is selected from at least one of BYK-161, TOL-501 and ATU; The defoamer is selected from at least one of BYK-066N, Tech-367 and NYK-052.

5. The anti-corrosion coating material according to claim 1, wherein, The composite coating topcoat is a fluorine-modified composite coating topcoat, which includes component E and component F. Component E includes the following components by weight: 30-60 parts of hydroxypropyl resin, preferably 40-60 parts; 2-15 parts of solvent, preferably 2-10 parts; 1-15 parts of fluorine-containing functional powder, preferably 2-8 parts; 5-35 parts of filler, preferably 10-30 parts; 10-40 parts of pigment, preferably 15-30 parts; 0.1-5 parts of ultraviolet light absorber, preferably 0.5-1.5 parts; and 0.1-5 parts of light stabilizer, preferably 0.5-2 parts. Component F includes the following components by weight: 60-90 parts of HDI trimer curing agent, preferably 70-80 parts; and 10-40 parts of solvent, preferably 20-30 parts. The mass ratio of component E to component F is 4-15:

1.

6. The anti-corrosion coating material according to claim 5, wherein, The E component further includes at least one selected from 0.1 to 5 parts of a thixotropic agent, 0.1 to 5 parts of a dispersant, and 0.1 to 5 parts of an antifoaming agent; In component E, the hydroxypropyl resin is selected from at least one of LR-7765, SM513 / 60LG, and FX-9070; The fluorinated functional powder is 800-1200 mesh polytetrafluoroethylene powder; The filler is 800-1200 mesh modified ultrafine barium sulfate; The pigment is selected from titanium dioxide and / or carbon black; The ultraviolet light absorber is 2-(2H-benzotriazol-2-yl)-4,6-ditert-pentylphenol; The light stabilizer is mono(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate; In component F, the HDI trimer curing agent is HT100 and / or N3390; The solvents in components E and F are each independently diol esters and / or polyesters, preferably selected from PMA and / or DBE; The thixotropic agent is selected from at least one of organic bentonite 140, bentonite 979, polyamide wax powder HX-9110, fumed silica A200 and polyethylene wax paste 202P. The dispersant is selected from at least one of BYK-161, TOL-501 and ATU; The defoamer is selected from at least one of BYK-066N, Tech-367 and NYK-052.

7. The method for preparing the anti-corrosion coating material according to any one of claims 1-6, characterized in that, Includes the following steps: The preparation method of conductive modified epoxy zinc-rich primer is as follows: Preparation of component A: ① Mix the epoxy resin and solvent, stirring at low speed; ② Add conductive modifier and optional thixotropic agent, optional dispersant, optional defoamer, and stir at medium speed to disperse; ③ Add the flaky zinc powder, stir and disperse at medium speed, and control the temperature at 40-45℃; ④ Cool down to 25-30℃, control the slurry fineness ≤60μm, add accelerator, stir evenly, and obtain component A; Preparation of component B: Modified phenolic amine curing agent, modified alicyclic amine curing agent and solvent are mixed by stirring at medium speed to obtain component B; Component A and component B are mixed to obtain the conductive modified epoxy zinc-rich primer; Preferably, the low-speed stirring conditions include a speed of 400-600 r / min and a time of 5-40 min; the medium-speed stirring conditions include a speed of 700-800 r / min and a time of 5-40 min.

8. The preparation method according to claim 7, wherein, It also includes the preparation steps of fiber-modified epoxy micaceous iron oxide intermediate paint and fluorine-modified composite coating topcoat; The preparation method of fiber-modified epoxy micaceous iron oxide intermediate varnish is as follows: Preparation of component C: ① Mix epoxy resin, reactive diluent and solvent, stirring at low speed; ② Add fiber film-forming aids and optional thixotropic agents, optional dispersants, and optional defoamers, and disperse by high-speed stirring; ③ Add flaky mica iron oxide, filler and pigment, stir and disperse at high speed, and control the temperature at 40-45℃; ④ Cool down to 25-30℃, control the slurry fineness to ≤60μm, and obtain the C component; Preparation of component D: Polyamide curing agent, fatty amine curing agent and solvent are mixed by stirring at medium speed to obtain component D; Components C and D are mixed to obtain fiber-modified epoxy micaceous iron oxide intermediate paint; The preparation method of fluorine-modified composite coating topcoat is as follows: Preparation of component E: ① Mix hydroxypropyl resin and solvent, stirring at low speed; ② Add optional thixotropic agent, optional dispersant, and optional defoamer, and disperse by high-speed stirring; ③ Add fluorine-containing functional powders, fillers and pigments, and stir and disperse them at high speed, controlling the temperature at 40-45℃; ④ Cool down to 25-30℃ and control the slurry fineness to ≤30μm; ⑤ Add ultraviolet light absorber and light stabilizer, stir and disperse at medium speed to obtain component E; Preparation of component F: HDI trimer curing agent and solvent are dispersed by medium-speed stirring to obtain component F; Component E and component F are mixed to obtain the fluorine-modified composite coating topcoat; Preferably, the low-speed stirring conditions include a speed of 400-600 r / min and a time of 5-40 min; the medium-speed stirring conditions include a speed of 700-800 r / min and a time of 5-40 min; and the high-speed stirring conditions include a speed of 1000-1100 r / min and a time of 5-40 min.

9. The application of the anti-corrosion coating material according to any one of claims 1-6 as an anti-corrosion coating on the outer surface of the floating roof of an oil storage tank.

10. The application according to claim 9, wherein, The thickness of the conductive modified epoxy zinc-rich primer layer is 80–100 μm; The thickness of the fiber-modified epoxy micaceous iron oxide intermediate coating is 120–160 μm; The thickness of the topcoat layer of the fluorine-modified composite coating is 80–100 μm.

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