A composite coating material and a method for producing the same

Abstract

The application provides a composite coating material and a preparation method thereof, and belongs to the technical field of coating materials.The composite coating material comprises a primer layer, an intermediate paint fiber mixture layer and a top paint fiber mixture layer which are sequentially stacked; the intermediate paint fiber mixture layer comprises a first fiber mesh cloth and an intermediate paint layer embedded in the first fiber mesh cloth; and the top paint fiber mixture layer comprises a second fiber mesh cloth and a top paint layer embedded in the second fiber mesh cloth.The application designs the structure of the composite coating material and the specific composition of the primer slurry for forming the primer layer, the intermediate paint slurry for forming the intermediate paint layer and the top paint slurry for forming the top paint layer, so that the composite coating material with good corrosion resistance, wear resistance, low-temperature resistance, temperature change resistance and long service life is prepared.

Description

Technical Field

[0001] This invention belongs to the field of coating materials technology, specifically relating to a composite coating material and its preparation method. Background Technology

[0002] With economic development, rail transit freight cars, passenger cars, and bullet trains need to pass through high-altitude and cold regions. Therefore, there is a great demand for functional coating materials, and existing technologies are increasingly researching functional coating materials.

[0003] CN111849351A discloses a composite material, its preparation method, wear-resistant and anti-corrosion coating, and its application. The composite material comprises component A and component B. Component A includes the following raw materials in parts by weight: 5-10 parts of anti-rust pigment and 90-110 parts of fluorosilicone anti-corrosion coating. Component B includes the following raw materials in parts by weight: 20-50 parts of nano-sized silicon carbide powder, 70-110 parts of fluorosilicone anti-corrosion coating, and 0.1-2 parts of silane coupling agent. The composite material provided by this technical solution can cure rapidly at room temperature, and the preparation method is simple. The prepared composite material can be used for anti-corrosion construction and has excellent hardness and weather resistance. However, the wear resistance, low-temperature resistance, and temperature change resistance of the composite material provided by this technical solution are relatively poor.

[0004] CN113527980A discloses a composite nano-based wear-resistant coating material, relating to the field of chemical lubrication coating technology. It comprises an epoxy resin or polyimide resin solution, organic amines, accelerators, coupling agents, thixotropic agents, lubricants, wear-resistant additives, carbon fibers, dispersants, leveling agents, and solvents, synthesized in a certain proportion to form the wear-resistant coating material. The coating material provided by this technical solution exhibits poor wear resistance, low-temperature resistance, and temperature change resistance.

[0005] Current coating products for rail transit generally require resistance to temperatures as low as -20°C, but existing coated steel materials do not meet the requirements of these high-altitude and cold regions. Meanwhile, railway freight cars, passenger cars, and high-speed trains traversing high-altitude and cold regions or desert areas require good wear resistance due to friction from ice and sand. Furthermore, railway freight cars require an 8-year maintenance period due to wear, and their car body lifespan is only two operating cycles.

[0006] Therefore, how to provide a composite coating material with good corrosion resistance, wear resistance, low temperature resistance and temperature change resistance, long service life and usability in cold regions has become an urgent technical problem to be solved. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the present invention aims to provide a composite coating material and its preparation method. By designing the structure of the composite coating material and the specific compositions of the primer slurry forming the primer layer, the intermediate slurry forming the intermediate layer, and the topcoat slurry forming the topcoat layer, the present invention prepares a composite coating material with good corrosion resistance, wear resistance, low-temperature resistance, and temperature change resistance, and a long service life.

[0008] To achieve this objective, the present invention adopts the following technical solution:

[0009] In a first aspect, the present invention provides a composite coating material comprising a primer layer, an intermediate paint fiber mixture layer, and a topcoat fiber mixture layer stacked sequentially; the intermediate paint fiber mixture layer comprises a first fiber mesh and an intermediate paint layer nested within the first fiber mesh; the topcoat fiber mixture layer comprises a second fiber mesh and a topcoat layer nested within the second fiber mesh; the primer slurry forming the primer layer comprises the following components in parts by weight: 10-60 parts of epoxy-modified nitrile latex A, 0.1-70 parts of modified zinc powder, and 0.1-80 parts of zinc phosphate; the intermediate paint slurry forming the intermediate paint layer comprises the following components in parts by weight: 20-60 parts of epoxy-modified nitrile latex B, and hollow glass microspheres A. The topcoat slurry forming the topcoat layer comprises the following components in parts by weight: 30-70 parts acrylic modified nitrile latex, 10-20 parts hollow glass microspheres B, 10-20 parts silicon carbide, 20-50 parts titanium dioxide, 1-20 parts carbon black, and 10-100 parts barium sulfate.

[0010] In this invention, by designing the structure of the composite coating material, the intermediate paint layer is nested within a first fiber mesh in the intermediate paint fiber mixture layer, and the topcoat layer is nested within a second fiber mesh in the topcoat fiber mixture layer. This nested structure of the fiber mesh and paint layers reduces the impact force received by the composite coating material, thus improving its wear resistance. Specifically, the intermediate paint fiber mixture layer uses the first fiber mesh as its framework, with the intermediate paint layer nested within it. Similarly, the topcoat fiber mixture layer uses the second fiber mesh as its framework, with the topcoat layer nested within it. Utilizing the excellent mechanical properties (high tensile strength, high tear strength, and high impact strength) and unique mesh structure of the fiber mesh, the stress received by the composite coating material is dispersed and reduced by the fiber mesh, thereby improving its wear resistance.

[0011] Meanwhile, when the topcoat layer is nested within the second fiber mesh in the topcoat fiber mixture layer, a concave micro-honeycomb structure is formed on its surface, thus creating a hydrophobic interface to prevent surface icing. Furthermore, the presence of this concave micro-honeycomb structure reduces the area of ​​the composite coating material subjected to friction, improving its wear resistance. The concave micro-honeycomb structure on the surface of the topcoat fiber mixture layer also allows air to be trapped within it, forming an air layer that enhances the low-temperature resistance and temperature change resistance of the composite coating material.

[0012] In this invention, by designing the composite coating material and through the synergistic effect of its components, a composite coating material with good salt spray resistance, wear resistance, low-temperature resistance, and temperature change resistance, as well as a long service life, is prepared. Furthermore, the composite coating material provided by this invention has low material cost, facilitating industrial production and use.

[0013] In this invention, the primer slurry, intermediate slurry, and topcoat slurry are all single-component coatings. Compared with the two-component coatings in the prior art, their preparation method is simpler and their use is more convenient. Furthermore, in this invention, the use of epoxy-modified nitrile butadiene latex A, epoxy-modified nitrile butadiene latex B, and acrylic-modified nitrile butadiene latex enables the composite coating material to possess good salt spray resistance, abrasion resistance, low-temperature resistance, and temperature change resistance.

[0014] In this invention, the use of modified zinc powder and zinc phosphate in the primer slurry gives the composite coating material high corrosion resistance. The use of hollow glass microspheres A in the intermediate slurry and hollow glass microspheres B in the topcoat slurry gives the composite coating material good resistance to temperature changes and low temperatures. Simultaneously, the use of hollow glass microspheres A and silicon carbide in the intermediate slurry ensures that the composite coating material retains good wear resistance even after the topcoat layer is damaged, thus extending its service life. Combined with the use of hollow glass microspheres B and silicon carbide in the topcoat slurry, the resulting composite coating material exhibits high wear resistance, high low-temperature resistance, and good resistance to temperature changes.

[0015] In this invention, by controlling the amount of hollow glass microspheres and silicon carbide in the intermediate paint layer and the topcoat layer within a specific range, a composite coating material with excellent comprehensive performance was prepared.

[0016] In this invention, the first fiber mesh in the intermediate varnish fiber mixture layer and the second fiber mesh in the topcoat fiber mixture layer constitute a wear-resistant skeleton, which is the foundation for improving wear resistance. Simultaneously, the silicon carbide in both the intermediate and topcoat slurries possesses excellent hardness, further enhancing the overall wear resistance of the composite coating material. The hollow glass microspheres A in the intermediate varnish slurry and B in the topcoat slurry exhibit excellent thermal insulation properties. The honeycomb structure formed by the surface mesh of the intermediate and topcoat fiber mixture layers stores hot air, reducing surface temperature drop and acting as a heat insulator in the composite material, thus improving the cold resistance of the composite coating material. Furthermore, the honeycomb structure reduces the contact area, further enhancing the wear resistance of the composite coating material. The honeycomb structure also buffers external forces, preventing damage to the composite coating material and extending its lifespan.

[0017] In the primer slurry provided by the present invention, the weight parts of epoxy-modified nitrile latex A can be 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, or 60 parts, etc.

[0018] In the primer slurry, the weight parts of modified zinc powder can be 0.1 parts, 1 part, 2 parts, 5 parts, 10 parts, 20 parts, 30 parts, 40 parts, 50 parts, 60 parts or 70 parts, etc.

[0019] In the primer slurry, the weight parts of zinc phosphate can be 0.1 parts, 1 part, 5 parts, 10 parts, 20 parts, 30 parts, 40 parts, 50 parts, 60 parts, 70 parts or 80 parts, etc.

[0020] In the intermediate paint slurry provided by the present invention, the weight parts of epoxy-modified nitrile latex B can be 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, 55 parts, or 60 parts, etc.

[0021] In the intermediate paint slurry, the weight parts of hollow glass microspheres A can be 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 parts, etc.

[0022] In the intermediate varnish slurry, the weight parts of silicon carbide can be 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 parts, etc.

[0023] In intermediate paint slurry, the weight parts of titanium dioxide can be 5 parts, 5.5 parts, 6 parts, 6.5 parts, 7 parts, 7.5 parts, 8 parts, 8.5 parts, 9 parts, 9.5 parts, or 10 parts, etc.

[0024] In intermediate paint slurry, the weight parts of calcium carbonate can be 5 parts, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, or 50 parts, etc.

[0025] In intermediate paint slurry, the weight parts of barium sulfate can be 10, 20, 30, 40, 50, 60, 70, 80, 90 or 100 parts, etc.

[0026] In the topcoat slurry provided by the present invention, the weight parts of acrylic modified nitrile latex can be 30 parts, 33 parts, 36 parts, 39 parts, 42 parts, 46 parts, 49 parts, 52 parts, 55 parts, 57 parts, 60 parts, 63 parts, 66 parts, 69 parts, or 70 parts, etc.

[0027] In the topcoat slurry, the weight parts of hollow glass microspheres B can be 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 parts, etc.

[0028] In the topcoat slurry, the weight parts of silicon carbide can be 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 parts, etc.

[0029] In the topcoat slurry, the weight parts of titanium dioxide can be 20 parts, 23 parts, 26 parts, 29 parts, 32 parts, 35 parts, 38 parts, 40 parts, 42 parts, 44 parts, 46 parts, 48 ​​parts, or 50 parts, etc.

[0030] In the topcoat slurry, the weight parts of carbon black can be 1 part, 2 parts, 4 parts, 6 parts, 8 parts, 10 parts, 12 parts, 14 parts, 16 parts, 18 parts, or 20 parts, etc.

[0031] In the topcoat slurry, the weight of barium sulfate can be 10 parts, 20 parts, 30 parts, 40 parts, 50 parts, 60 parts, 70 parts, 80 parts, 90 parts or 100 parts, etc.

[0032] It should be noted that the composite coating provided by the present invention is not limited to a three-layer structure (a primer layer, an intermediate paint fiber mixture layer, and a topcoat fiber mixture layer stacked sequentially), but can also be a multi-layer structure, such as the composite coating consisting of a primer layer, an intermediate paint fiber mixture layer, and a topcoat fiber mixture layer stacked repeatedly.

[0033] The following are preferred technical solutions of the present invention, but are not intended to limit the technical solutions provided by the present invention. The purpose and beneficial effects of the present invention can be better achieved and realized through the following preferred technical solutions.

[0034] Preferably, the raw materials for preparing the epoxy-modified nitrile latex A and the epoxy-modified nitrile latex B each independently include cross-linked epoxy emulsion, nitrile latex, lithium magnesium silicate, silane coupling agent, defoamer A, and pH adjuster A.

[0035] In this invention, by selecting cross-linked epoxy emulsions to prepare epoxy-modified nitrile butadiene latex A and epoxy-modified nitrile butadiene latex B, the overall performance of the composite coating material is further improved.

[0036] Preferably, the mass ratio of the crosslinked epoxy emulsion to the nitrile latex is 10:90-80:20, for example, it can be 10:90, 15:85, 20:80, 25:75, 30:70, 35:65, 40:60, 45:55, 50:50, 55:45, 60:40, 65:35, 70:30, 75:25 or 80:20, etc.

[0037] Preferably, based on a total mass fraction of 100 parts for the cross-linked epoxy emulsion and the nitrile latex, the mass fraction of lithium magnesium silicate is 0.03-0.6 parts, for example, 0.03 parts, 0.05 parts, 0.1 parts, 0.15 parts, 0.2 parts, 0.25 parts, 0.3 parts, 0.35 parts, 0.4 parts, 0.45 parts, 0.5 parts, 0.55 parts, or 0.6 parts, etc.

[0038] Preferably, based on a total mass fraction of 100 parts for the combined epoxy emulsion and the nitrile latex, the mass fraction of the silane coupling agent is 0.1-1 parts, for example, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, or 1 part, etc.

[0039] Preferably, based on a total mass fraction of 100 parts for the combined epoxy emulsion and the nitrile latex, the mass fraction of the defoamer A is 0.01-1 parts, for example, 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, or 1 part, etc.

[0040] Preferably, based on a total mass fraction of 100 parts for the combined epoxy emulsion and the nitrile latex, the mass fraction of the pH adjuster A is 0.01-1 parts, for example, 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, or 1 part, etc.

[0041] In this invention, pH adjuster A is used to adjust the pH of the reaction system for preparing epoxy-modified nitrile butadiene latex A and epoxy-modified nitrile butadiene latex B to 7-8.

[0042] Preferably, the solid content of the crosslinked epoxy emulsion is 40-50%, for example, it can be 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, or 50%.

[0043] Preferably, the solid content of the nitrile latex is 35-50%, for example, it can be 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, or 50%.

[0044] Preferably, the silane coupling agent comprises any one or a combination of at least two of the following: γ-(2,3-epoxypropoxy)propyltrimethoxysilane (KH-560), tridecafluorooctyltriethoxysilane, heptadecylfluorodecyltriethoxysilane, trifluoropropyltrimethoxysilane, fluorophenyltrimethoxysilane, fluoroalkylaminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane (KH550), and γ-methacryloyloxypropyltrimethoxysilane (KH570).

[0045] Preferably, the fluorophenyltrimethoxysilane includes any one or a combination of at least two of trimethoxy(4-fluorophenyl)silane, trimethoxy(pentafluorophenyl)silane, pentafluorophenylpropyltrimethoxysilane, and (2-fluorophenyl)trimethylsilane.

[0046] Preferably, the fluoroalkylaminopropyltriethoxysilane comprises 3-aminopropyltriethoxysilane and / or N-aminoethyl-3-aminopropyltriethoxysilane.

[0047] Preferably, the defoamer A includes any one or a combination of at least two of the following: silicone defoamer, polyether defoamer, and mineral oil defoamer.

[0048] Preferably, the pH adjuster A comprises any one or a combination of at least two of 2-amino-2-methyl-1-propanol (AMP95), 3-aminopropyltriethoxysilane, and ethanolamine.

[0049] Preferably, the epoxy-modified nitrile butadiene latex A and the epoxy-modified nitrile butadiene latex B are each prepared independently using the following method, which includes the following steps:

[0050] After mixing cross-linked epoxy emulsion, defoamer A, and pH adjuster A, nitrile latex and lithium magnesium silicate are added sequentially, mixed, heated, and then a silane coupling agent is added. The mixture is reacted, kept warm to defoam, and then cooled to obtain epoxy-modified nitrile latex A or epoxy-modified nitrile latex B.

[0051] Preferably, the method for adding the lithium magnesium silicate includes mixing lithium magnesium silicate and water to prepare a lithium magnesium silicate solution before adding it.

[0052] In this invention, the method for adding lithium magnesium silicate includes mixing lithium magnesium silicate and water to prepare a lithium magnesium silicate solution before adding it. This invention does not impose any special limitations on the mass concentration of the lithium magnesium silicate solution, and exemplary concentrations include, but are not limited to, 2-4%, such as 2%, 2.2%, 2.4%, 2.6%, 2.8%, 3%, 3.2%, 3.4%, 3.6%, 3.8%, or 4%, etc.

[0053] Preferably, the temperature after heating is 35-50℃, for example, it can be 35℃, 36℃, 38℃, 40℃, 42℃, 44℃, 46℃, 48℃ or 50℃, etc.

[0054] Preferably, the method of adding the silane coupling agent includes dropwise addition.

[0055] Preferably, the reaction time is 1-3 hours, for example, 1 hour, 1.5 hours, 2 hours, 2.5 hours or 3 hours.

[0056] Preferably, the heat preservation and degassing time is 20-28 hours, for example, it can be 20 hours, 21 hours, 22 hours, 23 hours, 24 hours, 25 hours, 26 hours, 27 hours or 28 hours.

[0057] Preferably, the temperature after cooling is room temperature.

[0058] In this invention, the epoxy-modified nitrile butadiene latex A and the epoxy-modified nitrile butadiene latex B are each prepared independently using the following method, which specifically includes the following steps:

[0059] Crosslinked epoxy emulsion, defoamer A, and pH adjuster A are mixed, and then nitrile latex is added and mixed. Then, lithium magnesium silicate solution is added and mixed. The mixture is heated to 35-50°C, and then silane coupling agent is added dropwise. After reacting for 1-3 hours, the mixture is kept at this temperature for 20-28 hours to defoam, and then cooled to room temperature to obtain epoxy-modified nitrile latex A or epoxy-modified nitrile latex B.

[0060] Preferably, the raw materials for preparing the acrylic modified nitrile latex include the following components in parts by weight: 1-50 parts of cross-linked acrylic emulsion, 50-90 parts of nitrile latex, 0.1-10 parts of alkali-swellable acrylic acid, 0.01-1 parts of defoamer B, 0.01-1 parts of pH adjuster B, and 0.1-5 parts of fluorinated silane coupling agent.

[0061] In this invention, the mass fraction of the cross-linked acrylic emulsion in the raw materials for preparing the acrylic-modified nitrile latex can be 1 part, 5 parts, 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, or 50 parts, etc.

[0062] In the raw materials for preparing acrylic modified nitrile latex, the mass fraction of nitrile latex can be 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts, 80 parts, 85 parts, or 90 parts, etc.

[0063] In the raw materials for preparing the acrylic-modified nitrile latex, the mass fraction of alkali-swellable acrylic acid can be 0.1 parts, 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, or 10 parts, etc.

[0064] In the raw materials for preparing the acrylic modified nitrile latex, the mass fraction of defoamer B can be 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, or 1 part, etc.

[0065] In the raw materials for preparing the acrylic modified nitrile latex, the mass fraction of pH adjuster B can be 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, or 1 part, etc.

[0066] In the raw materials for preparing acrylic modified nitrile latex, the mass fraction of the fluorinated silane coupling agent can be 0.1 parts, 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, or 5 parts, etc.

[0067] Preferably, the solid content of the crosslinked acrylic emulsion is 35-50%, for example, it can be 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, or 50%.

[0068] Preferably, the solid content of the nitrile latex is 35-50%, for example, it can be 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, or 50%.

[0069] Preferably, the fluorinated silane coupling agent comprises any one or a combination of at least two of the following: heptadecyltrimethoxysilane (LK-17), tridecafluorooctyltriethoxysilane, trifluoropropyltrimethoxysilane, fluorophenyltrimethoxysilane, and fluoroalkylaminopropyltriethoxysilane.

[0070] Preferably, the defoamer B includes any one or a combination of at least two of the following: silicone defoamer, polyether defoamer, and mineral oil defoamer.

[0071] Preferably, the pH adjuster B comprises any one or a combination of at least two of 2-amino-2-methyl-1-propanol (AMP95), 3-aminopropyltriethoxysilane, and ethanolamine.

[0072] In this invention, pH adjuster B is used to adjust the pH of the reaction system for preparing acrylic modified nitrile butadiene latex to 7-8.

[0073] Preferably, the acrylic-modified nitrile latex is prepared by the following method, which includes the following steps:

[0074] After mixing cross-linked acrylic emulsion, defoamer B, and pH adjuster B, nitrile latex and alkali-swellable acrylic acid are added sequentially, mixed, heated, and then a fluorosilane coupling agent is added. The mixture is reacted, kept warm to defoam, and then cooled to obtain the acrylic-modified nitrile latex.

[0075] Preferably, the temperature after heating is 10-35℃, for example, it can be 10℃, 12℃, 14℃, 16℃, 18℃, 20℃, 22℃, 24℃, 26℃, 28℃, 30℃, 32℃, 33℃ or 35℃, etc.

[0076] Preferably, the method of adding the fluorinated silane coupling agent includes dropwise addition.

[0077] Preferably, the reaction time is 3-5 hours, for example, 3 hours, 3.5 hours, 4 hours, 4.5 hours or 5 hours.

[0078] Preferably, the heat preservation and degassing time is 20-28 hours, for example, it can be 20 hours, 21 hours, 22 hours, 23 hours, 24 hours, 25 hours, 26 hours, 27 hours or 28 hours.

[0079] Preferably, the temperature after cooling is room temperature.

[0080] In this invention, the acrylic-modified nitrile latex is prepared by the following method, which specifically includes the following steps:

[0081] Crosslinked acrylic emulsion, defoamer B, and pH adjuster B are mixed together. Nitrile latex is then added and mixed. Then, alkali is added to swell acrylic acid, and the mixture is stirred. The mixture is heated to 10-35°C, and a fluorosilane coupling agent is added dropwise. After reacting for 3-5 hours, the mixture is kept at this temperature for 20-28 hours to defoam. After cooling, the acrylic-modified nitrile latex is obtained.

[0082] Preferably, the average particle size of the hollow glass microspheres A and B is independently ≤0.5 mm, for example, it can be 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm or 0.5 mm, etc.

[0083] Preferably, in the intermediate paint slurry, the mass ratio of hollow glass microspheres A to silicon carbide is (0.5-1):1, for example, it can be 0.5:1, 0.55:1, 0.6:1, 0.65:1, 0.7:1, 0.75:1, 0.8:1, 0.85:1, 0.9:1, 0.95:1 or 1:1, etc.

[0084] Preferably, in the topcoat slurry, the mass ratio of hollow glass microspheres B to silicon carbide is (0.5-1):1, for example, it can be 0.5:1, 0.55:1, 0.6:1, 0.65:1, 0.7:1, 0.75:1, 0.8:1, 0.85:1, 0.9:1, 0.95:1 or 1:1, etc.

[0085] In this invention, by controlling the amount of hollow glass microspheres B in the topcoat slurry to be less than or equal to the amount of silicon carbide, the overall performance of the composite coating material is further improved.

[0086] Preferably, the primer slurry, the intermediate slurry, and the topcoat slurry each independently further include the following components in parts by weight: 0.1-10 parts wetting and dispersing agent, 0.01-1 parts acid-base regulator, 0.1-5 parts defoamer C, 0.1-1 parts leveling agent, 0.1-2 parts rust inhibitor, 0.1-10 parts film-forming aid, and 0-1 parts defoamer.

[0087] In this invention, the weight parts of the wetting and dispersing agent in the primer slurry, the intermediate slurry, and the topcoat slurry can each be independently 0.1 parts, 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, or 10 parts, etc.

[0088] The weight percentages of the acid-base adjuster in the primer slurry, the intermediate slurry, and the topcoat slurry can each be independently 0.01 parts, 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, or 1 part, etc.

[0089] The weight percentages of defoamer C in the primer slurry, the intermediate slurry, and the topcoat slurry can each be independently 0.1 parts, 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, or 5 parts, etc.

[0090] The weight percentages of leveling agent in the primer, intermediate coat, and topcoat can each be independently 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, or 1 part, etc.

[0091] The weight percentages of the rust inhibitor in the primer, intermediate paint, and topcoat can each be independently 0.1, 0.2, 0.4, 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, or 2 parts, etc.

[0092] The weight percentages of film-forming aids in the primer slurry, the intermediate slurry, and the topcoat slurry can each be independently 0.1 parts, 0.5 parts, 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, or 10 parts, etc.

[0093] The weight percentages of defoamer in the primer, intermediate paint, and topcoat can each be 0 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, or 1 part, etc.

[0094] It should be noted that the present invention does not impose any special restrictions on the specific selection of wetting and dispersing agents, acid-base regulators, defoamers C, leveling agents, rust inhibitors, film-forming aids, and defoamers, and all of the above-mentioned aids commonly used in the art are applicable.

[0095] Preferably, the primer, intermediate coat, and topcoat each independently include water.

[0096] Preferably, the viscosity of the primer slurry at 25°C is 80-120 KU, for example, it can be 80 KU, 85 KU, 90 KU, 95 KU, 100 KU, 105 KU, 110 KU, 115 KU or 120 KU.

[0097] Preferably, the viscosity of the intermediate paint slurry at 25°C is 80-120 KU, for example, it can be 80 KU, 85 KU, 90 KU, 95 KU, 100 KU, 105 KU, 110 KU, 115 KU or 120 KU, etc.

[0098] Preferably, the viscosity of the topcoat slurry at 25°C is 80-120 KU, for example, it can be 80 KU, 85 KU, 90 KU, 95 KU, 100 KU, 105 KU, 110 KU, 115 KU or 120 KU.

[0099] The viscosity testing method for primer slurry, intermediate slurry and topcoat slurry provided by the present invention can adopt GB / T9269-2009 Determination of viscosity of coatings by Stormer viscometer method.

[0100] It should be noted that the preparation method of the primer slurry in this invention is not particularly limited, and exemplary methods include, but are not limited to, mixing the components of the primer slurry evenly to obtain the primer slurry. Similarly, the preparation method of the intermediate paint slurry in this invention is not particularly limited, and exemplary methods include, but are not limited to, mixing the components of the intermediate paint slurry evenly to obtain the intermediate paint slurry. Similarly, the preparation method of the topcoat slurry in this invention is not particularly limited, and exemplary methods include, but are not limited to, mixing the components of the topcoat slurry evenly to obtain the topcoat slurry.

[0101] Preferably, the first fiber mesh and the second fiber mesh are each independently selected from any one of glass fiber mesh, carbon fiber mesh, nylon fiber mesh, and ultra-high molecular weight polyethylene fiber mesh.

[0102] It should be noted that the first fiber mesh and the second fiber mesh in this invention can also be replaced by corresponding fibers, filaments or nets.

[0103] Preferably, the thickness of the primer layer is 30-100 μm, for example, it can be 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm or 100 μm, etc.

[0104] Preferably, the thickness of the first fiber mesh is 50-500 μm, for example, it can be 50 μm, 100 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm or 500 μm.

[0105] Preferably, the thickness of the intermediate paint layer is 30-100 μm, for example, it can be 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm or 100 μm, etc.

[0106] Preferably, the thickness of the second fiber mesh is 50-500 μm, for example, it can be 50 μm, 100 μm, 200 μm, 250 μm, 300 μm, 350 μm, 400 μm, 450 μm or 500 μm.

[0107] Preferably, the thickness of the topcoat layer is 20-100 μm, for example, it can be 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 70 μm, 75 μm, 80 μm, 85 μm, 90 μm or 100 μm, etc.

[0108] Preferably, a first adhesive layer is further provided between the primer layer and the intermediate varnish fiber mixture layer.

[0109] Preferably, the thickness of the first adhesive layer is 10-300 μm, for example, it can be 10 μm, 20 μm, 40 μm, 60 μm, 80 μm, 100 μm, 120 μm, 140 μm, 160 μm, 180 μm, 200 μm, 220 μm, 240 μm, 260 μm, 280 μm or 300 μm, etc.

[0110] Preferably, a second adhesive layer is further provided between the intermediate paint fiber mixture layer and the topcoat fiber mixture layer.

[0111] Preferably, the thickness of the second adhesive layer is 10-300 μm, for example, it can be 10 μm, 20 μm, 40 μm, 60 μm, 80 μm, 100 μm, 120 μm, 140 μm, 160 μm, 180 μm, 200 μm, 220 μm, 240 μm, 260 μm, 280 μm or 300 μm, etc.

[0112] Preferably, the materials of the first adhesive layer and the second adhesive layer each independently comprise an epoxy-modified nitrile butadiene adhesive.

[0113] It should be noted that in this invention, the epoxy-modified nitrile adhesive can also be replaced with other low-temperature resistant adhesives, as long as they can bond the primer layer and the intermediate varnish fiber mixture layer, and the intermediate varnish fiber mixture layer and the topcoat fiber mixture layer.

[0114] In a second aspect, the present invention provides a method for preparing a composite coating material as described in the first aspect, the method comprising the following steps:

[0115] (1) After spraying the primer onto the substrate, a first fiber mesh is set up and dried to form a film;

[0116] (2) After spraying the intermediate paint slurry on the side of the first fiber mesh away from the substrate, the second fiber mesh is set and dried to form a film;

[0117] (3) On the side of the second fiber mesh away from the substrate, spray the topcoat slurry and dry it to form a film to obtain the composite coating material.

[0118] It should be noted that if a first adhesive layer is provided between the primer layer and the intermediate paint fiber mixture layer, and a second adhesive layer is provided between the intermediate paint fiber mixture layer and the topcoat fiber mixture layer, then the preparation method of the composite coating material is as follows:

[0119] (S1) Spray primer slurry onto the substrate, dry it to form a film, and obtain the primer layer;

[0120] (S2) After applying the first adhesive to the side of the primer layer away from the substrate, a first fiber mesh is set on the side of the first adhesive, the intermediate paint slurry is sprayed, and the film is dried to obtain an intermediate paint fiber mixture layer on the side of the primer layer away from the substrate layer.

[0121] (S3) After applying the second adhesive to the side of the intermediate paint fiber mixture layer away from the substrate, a second fiber mesh is set on the side of the second adhesive, the topcoat slurry is sprayed, and the film is dried to form a topcoat fiber mixture layer on the side of the intermediate paint fiber mixture layer away from the primer layer, thus completing the preparation of the composite coating material.

[0122] Alternatively, the preparation method of the composite coating material includes the following steps:

[0123] (S1) Spray primer slurry onto the substrate, dry it to form a film, and obtain the primer layer;

[0124] (S2) Spray intermediate paint slurry onto one side of the first fiber mesh, dry to form a film, and obtain an intermediate paint fiber mixture layer;

[0125] The side of the primer away from the substrate layer and the side of the intermediate paint fiber mixture layer away from the intermediate paint layer are bonded together with a first adhesive to obtain an intermediate product;

[0126] (S3) Spray a topcoat slurry onto one side of the second fiber mesh and dry it to form a film to obtain a topcoat fiber mixture layer;

[0127] The intermediate product on the side away from the primer layer and the topcoat fiber mixture layer on the side away from the topcoat layer are bonded together using a second adhesive to obtain the composite coating material.

[0128] It should be noted that the present invention does not impose any special restrictions on the drying temperature and time during the preparation of composite coating materials, and commonly used drying process conditions in the art are applicable. For example, the drying temperature is 50-70℃ (e.g., 50℃, 52℃, 54℃, 56℃, 58℃, 60℃, 62℃, 64℃, 66℃, 68℃, or 70℃, etc.), and the drying time is 30-120 min (e.g., 30 min, 40 min, 50 min, 60 min, 70 min, 80 min, 90 min, 100 min, 110 min, or 120 min, etc.).

[0129] It should also be noted that the substrate can be a metal substrate or a non-metal substrate. Whether or not to peel off the substrate after preparing the composite coating material, or when to peel off the substrate, can be determined according to the application of the composite material.

[0130] Compared with the prior art, the present invention has the following beneficial effects:

[0131] (1) By designing the structure of the composite coating material and the composition of each layer, the present invention further designs the intermediate paint layer nested in the first fiber mesh and the topcoat layer nested in the second fiber mesh, and by utilizing the nested structure of the fiber mesh and the paint layer, a composite coating material with high low temperature resistance, wear resistance, salt spray resistance and temperature change resistance is prepared.

[0132] (2) By designing the specific composition of the primer slurry, intermediate slurry and topcoat slurry, the present invention prepares a composite coating material with high low temperature resistance, wear resistance, salt spray resistance and temperature change resistance through the synergistic effect of each component.

[0133] (3) By designing the structure of the composite coating material, and further by designing the intermediate paint fiber mixture layer and the topcoat fiber mixture layer with specific structures, the present invention forms a concave micro-honeycomb structure on the surface of the composite coating material, thereby further improving the comprehensive performance of the composite coating material. Attached Figure Description

[0134] Figure 1 This is a schematic diagram of the structure of the composite coating material provided in Embodiment 1 of the present invention;

[0135] Figure 2 This is a schematic diagram of the structure of the composite coating material provided in Embodiment 2 of the present invention;

[0136] Among them, 1-primer layer, 2-first adhesive layer, 3-intermediate paint fiber mixture layer, 4-second adhesive layer, and 5-topcoat fiber mixture layer. Detailed Implementation

[0137] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be considered as specific limitations thereof.

[0138] The sources of some components in the following examples and comparative examples are shown in Table 1 below:

[0139] Table 1

[0140]

[0141] Example 1

[0142] This embodiment provides a composite coating material, the structural schematic diagram of which is shown below. Figure 1 As shown, it includes a primer layer 1, a first adhesive layer 2, an intermediate paint fiber mixture layer 3, a second adhesive layer 4, and a topcoat fiber mixture layer 5, which are stacked in sequence; the intermediate paint fiber mixture layer 2 includes a first fiber mesh and an intermediate paint layer nested in the first fiber mesh; the topcoat fiber mixture layer 4 includes a second fiber mesh and a topcoat layer nested in the second fiber mesh.

[0143] The primer slurry forming the primer layer 1 comprises the following components in parts by weight: 50 parts epoxy-modified nitrile latex A, 70 parts modified zinc powder, 0.1 parts zinc phosphate, 2 parts wetting and dispersing agent, 0.2 parts acid-base regulator, 0.2 parts defoamer, 0.1 parts leveling agent, 0.5 parts rust inhibitor, 5 parts film-forming aid, and an appropriate amount of water. The viscosity of the primer slurry at 25°C is 100 KU.

[0144] The intermediate paint slurry forming the intermediate paint layer comprises the following components in parts by weight: 40 parts epoxy-modified nitrile latex B, 15 parts hollow glass microspheres A1, 20 parts silicon carbide, 5 parts titanium dioxide, 30 parts calcium carbonate, 90 parts barium sulfate, 1 part wetting and dispersing agent, 0.2 parts acid-base regulator, 0.2 parts defoamer, 0.1 parts leveling agent, 1 part rust inhibitor, 4 parts film-forming aid, 0.1 parts defoamer, and an appropriate amount of water. The viscosity of the intermediate paint slurry at 25°C is 100 KU.

[0145] The topcoat slurry forming the topcoat layer comprises the following components in parts by weight: 50 parts acrylic modified nitrile latex, 10 parts hollow glass microspheres B1, 10 parts silicon carbide, 20 parts titanium dioxide, 2 parts carbon black, 50 parts barium sulfate, 1 part wetting and dispersing agent, 0.2 parts acid-base regulator, 2 parts defoamer, 1 part leveling agent, 1 part rust inhibitor, 5 parts film-forming aid, 0.1 part defoamer, and an appropriate amount of water. The viscosity of the topcoat slurry at 25°C is 100 KU.

[0146] Both epoxy-modified nitrile butadiene latex A and epoxy-modified nitrile butadiene latex B were prepared using the following method: At 300 rpm, cross-linked epoxy emulsion A (20 parts by mass), defoamer (0.1 parts by mass), and AMP95 (0.2 parts by mass) were mixed evenly. Nitrile butadiene latex A (80 parts by mass) was added and stirred until homogeneous. Then, a 3% (w / w) lithium magnesium silicate aqueous solution (20 parts by mass) was added and stirred until homogeneous. The reaction system was then heated to 40°C, and silane coupling agent KH-560 (0.2 parts by mass) was added. The reaction was carried out for 2 hours under stirring at 300 rpm, followed by defoaming at the temperature for 24 hours. The mixture was then cooled to room temperature to obtain epoxy-modified nitrile butadiene latex A and epoxy-modified nitrile butadiene latex B.

[0147] The acrylic-modified nitrile butadiene latex was prepared by the following method: At 300 rpm, cross-linked acrylic emulsion A (40 parts by mass), defoamer (0.2 parts by mass), and AMP95 (0.2 parts by mass) were mixed evenly. Nitrile butadiene latex A (80 parts by mass) was added and stirred until homogeneous. Then, alkali-swelled acrylic acid (2 parts by mass) was added and stirred until homogeneous. At 25°C, heptadecafluorodecyltrimethoxysilane (1 part by mass) was added dropwise. After reacting for 4 h under stirring at 300 rpm, the mixture was kept at this temperature for defoaming for 24 h, and then cooled to obtain the acrylic-modified nitrile butadiene latex.

[0148] The preparation method of the above composite coating material is as follows:

[0149] (1) Spray primer slurry onto the substrate and dry it at 60°C to form a film, resulting in a primer layer with a thickness of 50 μm;

[0150] (2) After applying the first adhesive (coating thickness of 10 μm) on the side of the primer layer away from the substrate, a carbon fiber mesh A with a thickness of 50 μm is bonded to the side of the first adhesive, the intermediate paint slurry is sprayed, and the film is dried at 60°C to obtain an intermediate paint fiber mixture layer (intermediate paint layer thickness of 70 μm) on the side of the primer layer away from the substrate layer.

[0151] (3) After applying a second adhesive (coating thickness of 10 μm) to the side of the intermediate paint fiber mixture layer away from the substrate, a carbon fiber mesh A with a thickness of 50 μm is bonded to the side of the second adhesive, and a topcoat slurry is sprayed and dried at 60°C to form a film. A topcoat fiber mixture layer (topcoat thickness of 30 μm) is obtained on the side of the intermediate paint fiber mixture layer away from the primer layer, thus completing the preparation of the composite coating material.

[0152] Example 2

[0153] This embodiment provides a composite coating material, which includes a primer layer 1, an intermediate paint fiber mixture layer 3, and a topcoat fiber mixture layer 5 stacked sequentially; the intermediate paint fiber mixture layer 3 includes a first fiber mesh and an intermediate paint layer nested in the first fiber mesh; the topcoat fiber mixture layer 5 includes a second fiber mesh and a topcoat layer nested in the second fiber mesh.

[0154] The primer slurry forming the primer layer comprises the following components in parts by weight: 60 parts epoxy-modified nitrile latex A, 40 parts modified zinc powder, 20 parts zinc phosphate, 2 parts wetting and dispersing agent, 0.2 parts acid-base regulator, 0.2 parts defoamer, 0.1 parts leveling agent, 0.5 parts rust inhibitor, 6 parts film-forming aid, and an appropriate amount of water. The viscosity of the primer slurry at 25°C is 80 KU.

[0155] The intermediate paint slurry forming the intermediate paint layer comprises the following components in parts by weight: 60 parts epoxy-modified nitrile latex B, 20 parts hollow glass microspheres A2, 20 parts silicon carbide, 10 parts titanium dioxide, 50 parts calcium carbonate, 100 parts barium sulfate, 1 part wetting and dispersing agent, 0.2 parts acid-base regulator, 0.2 parts defoamer, 0.1 parts leveling agent, 1 part rust inhibitor, 9 parts film-forming aid, 0.5 parts defoamer, and an appropriate amount of water. The viscosity of the intermediate paint slurry at 25°C is 80 KU.

[0156] The topcoat slurry forming the topcoat layer comprises the following components in parts by weight: 40 parts acrylic modified nitrile latex, 20 parts hollow glass microspheres B2, 20 parts silicon carbide, 20 parts titanium dioxide, 5 parts carbon black, 10 parts barium sulfate, 1 part wetting and dispersing agent, 0.2 parts acid-base regulator, 2 parts defoamer, 1 part leveling agent, 1 part rust inhibitor, 10 parts film-forming aid, 0.5 parts defoamer, and an appropriate amount of water. The viscosity of the topcoat slurry is 80 KU at 25°C.

[0157] The epoxy-modified nitrile butadiene latex A and the epoxy-modified nitrile butadiene latex B were both prepared by the following method: At 300 rpm, cross-linked epoxy emulsion B (50 parts by mass), defoamer (0.2 parts by mass), and AMP95 (0.2 parts by mass) were mixed evenly. Nitrile butadiene latex B (50 parts by mass) was added and stirred until evenly mixed. Then, a 3% (w / w) lithium magnesium silicate aqueous solution (10 parts by mass) was added and mixed. The mixture was heated to 45°C, and then a silane coupling agent (0.5 parts by mass) was added. After reacting for 1.5 h, the mixture was kept at this temperature for 24 h to defoam, and then cooled to room temperature to obtain the epoxy-modified nitrile butadiene latex A and the epoxy-modified nitrile butadiene latex B.

[0158] The acrylic-modified nitrile butadiene latex was prepared by the following method: At 300 rpm, cross-linked acrylic emulsion B (5 parts by mass), defoamer (0.3 parts by mass), and AMP95 (0.1 parts by mass) were mixed evenly. Nitrile butadiene latex B (90 parts by mass) was added and stirred until homogeneous. Then, alkali-swellable acrylic acid (5 parts by mass) was added and stirred until homogeneous. At 20°C, a fluorosilane coupling agent (1.5 parts by mass) was added dropwise. After reacting for 4 h, the mixture was kept at this temperature for defoaming for 24 h, and then cooled to obtain the acrylic-modified nitrile butadiene latex.

[0159] The preparation method of the above composite coating material is as follows:

[0160] (1) After spraying primer slurry on the substrate, a carbon fiber mesh cloth B with a thickness of 500 μm is set on its surface and dried at 60°C to form a film, resulting in a primer layer with a thickness of 100 μm bonded with carbon fiber mesh cloth B.

[0161] (2) After spraying intermediate paint slurry on the side of the first fiber mesh away from the substrate, a carbon fiber mesh B with a thickness of 500 μm is set on its surface and dried at 60°C to form a film. An intermediate paint fiber mixture layer with carbon fiber mesh B bonded on the side of the primer layer away from the substrate layer is obtained (the thickness of the intermediate paint layer is 100 μm).

[0162] (3) On the side of the second fiber mesh away from the substrate, spray the topcoat slurry and dry it at 60°C to form a film. On the side of the intermediate paint fiber mixture layer away from the primer layer, the topcoat fiber mixture layer (the thickness of the topcoat layer is 100 μm) is obtained, and the preparation of the composite coating material is completed.

[0163] Example 3

[0164] This embodiment provides a composite coating material, which includes a primer layer, a first adhesive layer, an intermediate paint fiber mixture layer, a second adhesive layer, and a topcoat fiber mixture layer stacked sequentially; the intermediate paint fiber mixture layer includes a first fiber mesh and an intermediate paint layer nested in the first fiber mesh; the topcoat fiber mixture layer includes a second fiber mesh and a topcoat layer nested in the second fiber mesh.

[0165] The primer slurry forming the primer layer comprises the following components in parts by weight: 40 parts epoxy-modified nitrile latex A, 0.1 parts modified zinc powder, 80 parts zinc phosphate, 2 parts wetting and dispersing agent, 0.2 parts acid-base regulator, 0.2 parts defoamer, 0.1 parts leveling agent, 0.5 parts rust inhibitor, 4 parts film-forming aid, and an appropriate amount of water. The viscosity of the primer slurry at 25°C is 90 KU.

[0166] The intermediate paint slurry forming the intermediate paint layer comprises the following components in parts by weight: 40 parts epoxy-modified nitrile latex B, 12 parts hollow glass microspheres A2, 15 parts silicon carbide, 10 parts titanium dioxide, 45 parts calcium carbonate, 50 parts barium sulfate, 1 part wetting and dispersing agent, 0.2 parts acid-base regulator, 0.2 parts defoamer, 0.1 parts leveling agent, 1 part rust inhibitor, 8 parts film-forming aid, 0.5 parts defoamer, and an appropriate amount of water. The viscosity of the intermediate paint slurry at 25°C is 90 KU.

[0167] The topcoat slurry forming the topcoat layer comprises the following components in parts by weight: 30 parts acrylic modified nitrile latex, 12 parts hollow glass microspheres B1, 16 parts silicon carbide, 30 parts titanium dioxide, 20 parts carbon black, 20 parts barium sulfate, 1 part wetting and dispersing agent, 0.2 parts acid-base regulator, 2 parts defoamer, 1 part leveling agent, 1 part rust inhibitor, 4 parts film-forming aid, 0.6 parts defoamer, and an appropriate amount of water. The viscosity of the topcoat slurry at 25°C is 120 KU.

[0168] The epoxy-modified nitrile butadiene latex A and the epoxy-modified nitrile butadiene latex B were both prepared by the following method: At 300 rpm, cross-linked epoxy emulsion A (75 parts by mass), defoamer (0.2 parts by mass), and AMP95 (0.1 parts by mass) were mixed evenly. Nitrile butadiene latex B (25 parts by mass) was added and stirred until evenly mixed. Then, a 3% (w / w) lithium magnesium silicate aqueous solution (3 parts by mass) was added and stirred until evenly mixed. The reaction system was then heated to 35°C, and a silane coupling agent (0.6 parts by mass) was added. After reacting for 2 h, the system was kept at this temperature for 24 h to defoam, and then cooled to room temperature to obtain the epoxy-modified nitrile butadiene latex A and the epoxy-modified nitrile butadiene latex B.

[0169] The acrylic-modified nitrile butadiene latex was prepared by the following method: at 300 rpm, cross-linked acrylic emulsion A (50 parts by mass), defoamer (0.2 parts by mass) and AMP95 (0.1 parts by mass) were mixed evenly. Nitrile butadiene latex A (60 parts by mass) was added and stirred until evenly mixed. Then, alkali-swellable acrylic acid (4 parts by mass) was added and stirred until evenly mixed. The mixture was heated to 30°C, and a fluorosilane coupling agent was added dropwise. After reacting for 4 h, the mixture was kept at this temperature for 24 h to remove bubbles. After cooling, the acrylic-modified nitrile butadiene latex was obtained.

[0170] The preparation method of the above composite coating material is as follows:

[0171] (1) Spray primer slurry onto the substrate and dry it to form a film, resulting in a primer layer with a thickness of 70 μm;

[0172] (2) After applying the first adhesive (coating thickness of 100 μm) on the side of the primer layer away from the substrate, a glass fiber mesh cloth with a thickness of 50 μm is bonded to the side of the first adhesive, the intermediate paint slurry is sprayed, and the film is dried to obtain an intermediate paint fiber mixture layer (intermediate paint layer thickness of 50 μm) on the side of the primer layer away from the substrate layer.

[0173] (3) After applying a second adhesive (coating thickness of 100 μm) to the side of the intermediate paint fiber mixture layer away from the substrate, a glass fiber mesh cloth with a thickness of 50 μm is bonded to the side of the second adhesive, the topcoat slurry is sprayed, and the film is dried to obtain a topcoat fiber mixture layer (topcoat layer thickness of 20 μm) on the side of the intermediate paint fiber mixture layer away from the primer layer, thus completing the preparation of the composite coating material.

[0174] Example 4

[0175] This embodiment provides a composite coating material, which includes a primer layer, a first adhesive layer, an intermediate paint fiber mixture layer, a second adhesive layer, and a topcoat fiber mixture layer stacked sequentially; the intermediate paint fiber mixture layer includes a first fiber mesh and an intermediate paint layer nested in the first fiber mesh; the topcoat fiber mixture layer includes a second fiber mesh and a topcoat layer nested in the second fiber mesh.

[0176] The primer slurry forming the primer layer comprises the following components in parts by weight: 10 parts epoxy-modified nitrile latex A, 45 parts modified zinc powder, 30 parts zinc phosphate, 2 parts wetting and dispersing agent, 0.2 parts acid-base regulator, 0.2 parts defoamer, 0.1 parts leveling agent, 0.5 parts rust inhibitor, 1 part film-forming aid, and an appropriate amount of water. The viscosity of the primer slurry at 25°C is 120 KU.

[0177] The intermediate paint slurry forming the intermediate paint layer comprises the following components in parts by weight: 20 parts epoxy-modified nitrile latex B, 10 parts hollow glass microspheres A2, 10 parts silicon carbide, 10 parts titanium dioxide, 50 parts calcium carbonate, 10 parts barium sulfate, 1 part wetting and dispersing agent, 0.2 parts acid-base regulator, 0.2 parts defoamer, 0.1 parts leveling agent, 1 part rust inhibitor, 3 parts film-forming aid, 0.5 parts defoamer, and an appropriate amount of water. The viscosity of the intermediate paint slurry at 25°C is 120 KU.

[0178] The topcoat slurry forming the topcoat layer comprises the following components in parts by weight: 70 parts acrylic-modified nitrile latex, 10 parts hollow glass microspheres B2, 12 parts silicon carbide, 20 parts titanium dioxide, 1 part carbon black, 100 parts barium sulfate, 1 part wetting and dispersing agent, 0.2 parts acid-base regulator, 2 parts defoamer, 1 part leveling agent, 1 part rust inhibitor, 8 parts film-forming aid, 0.8 parts defoamer, and an appropriate amount of water. The viscosity of the topcoat slurry at 25°C is 90 KU.

[0179] The preparation methods of epoxy-modified nitrile butadiene latex A and epoxy-modified nitrile butadiene latex B are the same as in Example 1;

[0180] The preparation method of the acrylic modified nitrile latex is the same as that in Example 2.

[0181] The preparation method of the above composite coating material is as follows:

[0182] (1) Spray primer slurry onto the substrate and dry it to form a film, resulting in a primer layer with a thickness of 30 μm;

[0183] (2) After applying the first adhesive (coating thickness of 20 μm) on the side of the primer layer away from the substrate, a carbon fiber mesh A with a thickness of 50 μm is bonded to the side of the first adhesive, the intermediate paint slurry is sprayed, and the film is dried to obtain an intermediate paint fiber mixture layer (intermediate paint layer thickness of 50 μm) on the side of the primer layer away from the substrate layer.

[0184] (3) After applying a second adhesive (coating thickness of 10 μm) to the side of the intermediate paint fiber mixture layer away from the substrate, a carbon fiber mesh A with a thickness of 50 μm is bonded to the side of the second adhesive, a topcoat slurry is sprayed, and the mixture is dried to form a film. A topcoat fiber mixture layer (topcoat thickness of 20 μm) is obtained on the side of the intermediate paint fiber mixture layer away from the primer layer, thus completing the preparation of the composite coating material.

[0185] Example 5

[0186] This embodiment provides a composite coating material and its preparation method. The only difference from Embodiment 1 is that the amount of titanium dioxide in the topcoat slurry is adjusted from 20 parts by weight to 50 parts by weight, while other conditions are the same as in Embodiment 1.

[0187] Example 6

[0188] This embodiment provides a composite coating material and its preparation method. The only difference from Embodiment 1 is that the thickness of the topcoat layer in step (3) of preparing the composite coating material is 60 μm, and the other conditions are the same as in Embodiment 1.

[0189] Comparative Example 1

[0190] This embodiment provides a composite coating material and its preparation method. The only difference from Embodiment 1 is that silicon carbide is not used in the topcoat slurry, while the other conditions are the same as in Embodiment 1.

[0191] Comparative Example 2

[0192] This embodiment provides a composite coating material and its preparation method. The only difference from Embodiment 1 is that hollow glass microspheres B1 are not used in the topcoat slurry. Other conditions are the same as in Embodiment 1.

[0193] Comparative Example 3

[0194] This comparative example provides a composite coating material and its preparation method, which differs from Example 1 only in that: the composite coating material provided in this comparative example includes a primer layer, an intermediate paint layer, a second adhesive layer and a topcoat fiber mixture layer stacked sequentially; the topcoat fiber mixture layer includes a second fiber mesh and a topcoat layer nested in the second fiber mesh;

[0195] The step (2) of preparing the composite coating material is as follows: spray the intermediate paint slurry on the side of the primer layer away from the substrate, dry it to form a film, and obtain an intermediate paint layer with a thickness of 70 μm;

[0196] Step (3) is as follows: After applying the second adhesive (coating thickness of 10 μm) on the side of the intermediate paint layer away from the substrate, a carbon fiber mesh A with a thickness of 50 μm is bonded to the side of the second adhesive, the topcoat slurry is sprayed, and the film is dried to form a topcoat fiber mixture layer (topcoat layer thickness of 30 μm) is obtained on the side of the intermediate paint fiber mixture layer away from the primer layer, thus completing the preparation of the composite coating material.

[0197] Comparative Example 4

[0198] This comparative example provides a composite coating material and its preparation method, which differs from Example 1 only in that: the composite coating material provided in this comparative example includes a primer layer, a first adhesive layer, an intermediate paint fiber mixture layer and a topcoat layer stacked sequentially; the intermediate paint fiber mixture layer includes a first fiber mesh and an intermediate paint layer nested in the first fiber mesh.

[0199] The step (3) of preparing the composite coating material is as follows: spray the topcoat slurry on the side of the intermediate paint fiber mixture layer away from the substrate, dry it to form a film, and obtain a topcoat layer with a thickness of 30 μm, thus completing the preparation of the composite coating material.

[0200] Comparative Example 5

[0201] This comparative example provides a composite coating material and its preparation method, which differs from Example 1 only in that: the epoxy-modified nitrile latex A in the primer slurry is replaced with an equal weight of nitrile latex A, the epoxy-modified nitrile latex B in the intermediate slurry is replaced with an equal weight of nitrile latex A, and the acrylic-modified nitrile latex in the topcoat slurry is replaced with an equal weight of nitrile latex A. All other conditions are the same as in Example 1.

[0202] Comparative Example 6

[0203] This comparative example provides a composite coating material and its preparation method. The only difference from Example 1 is that modified zinc powder and zinc phosphate were not used in the primer slurry, while the other conditions are the same as in Example 1.

[0204] Comparative Example 7

[0205] This comparative example provides a composite coating material and its preparation method. The only difference from Example 1 is that hollow glass microspheres and silicon carbide are not used in the intermediate paint slurry. Other conditions are the same as in Example 1.

[0206] Comparative Example 8

[0207] This comparative example provides a composite coating material and its preparation method. The only difference from Example 1 is that hollow glass microspheres B1 and silicon carbide are not used in the topcoat slurry. Other conditions are the same as in Example 1.

[0208] Comparative Example 9

[0209] This comparative example provides a composite coating material and its preparation method, which differs from Example 1 only in that: the topcoat slurry forming the topcoat layer includes the following components in parts by weight: 50 parts acrylic modified nitrile latex, 92 parts silicon carbide, 1 part wetting and dispersing agent, 0.2 parts acid-base regulator, 2 parts defoamer, 1 part leveling agent, 1 part rust inhibitor, 5 parts film-forming aid, 0.1 part defoamer, and an appropriate amount of water. The viscosity of the topcoat slurry at 25°C is 100 KU, and other conditions are the same as in Example 1.

[0210] Comparative Example 10

[0211] This comparative example provides a composite coating material and its preparation method, which differs from Example 1 only in that: the topcoat slurry forming the topcoat layer includes the following components in parts by weight: 50 parts acrylic modified nitrile latex, 92 parts hollow glass microspheres B1, 1 part wetting and dispersing agent, 0.2 parts acid-base regulator, 2 parts defoamer, 1 part leveling agent, 1 part rust inhibitor, 5 parts film-forming aid, 0.1 part defoamer, and an appropriate amount of water. The viscosity of the topcoat slurry at 25°C is 120 KU, and other conditions are the same as in Example 1.

[0212] Comparative Example 11

[0213] This comparative example provides a composite coating material and its preparation method. The only difference from Example 1 is that the amount of epoxy-modified nitrile latex A in the primer slurry is adjusted to 5 parts, the amount of epoxy-modified nitrile latex B in the intermediate slurry is adjusted to 10 parts, and the amount of acrylic-modified nitrile latex in the topcoat slurry is adjusted to 20 parts. Other conditions are the same as in Example 1.

[0214] The performance of the composite coating materials provided in the above embodiments and comparative examples was tested, and the specific test methods are as follows:

[0215] Low temperature resistance: Tested according to the method provided in FZ / T 01007-2008;

[0216] Abrasion resistance: Tested according to the method provided in Clause 8.11 of GB / T 25042-2024;

[0217] Salt spray resistance: Tested according to the method provided in GB / T 1771-2007;

[0218] Temperature resistance to change: Tested according to the method described in GB / T 13492-2025 6.4.20.

[0219] The performance test results are shown in Table 2 below:

[0220] Table 2

[0221]

[0222]

[0223] As described above, this invention designs the structure of the composite coating material and the composition of each layer. Furthermore, by designing an intermediate paint fiber mixture layer nested within a first fiber mesh, and a topcoat fiber mixture layer nested within a second fiber mesh, this nested structure of the fiber mesh and paint layers yields a composite coating material with high low-temperature resistance, wear resistance, salt spray resistance, and temperature change resistance. This composite coating material exhibits no cracking, peeling, blistering, or crazing after more than 36 hours at -60℃. It withstands 15,000-20,000 revolutions of wear resistance testing. After 10,000 hours of salt spray testing, the composite coating material shows no peeling, blistering, or cracking, and the scratch boundary is ≤2 mm. Simultaneously, after more than 25 cycles of ±60℃ temperature resistance testing, the composite coating material shows no cracking or peeling.

[0224] As can be seen from the comparison between Example 1 and Comparative Examples 1-2, the present invention designs the composition of the topcoat layer and further improves the wear resistance of the composite coating material by using silicon carbide and hollow glass microspheres.

[0225] As can be seen from the comparison of Example 1 and Comparative Examples 3-4, the present invention, by designing the structure of the composite coating material and further by designing the intermediate paint fiber mixture layer and the topcoat fiber mixture layer with specific structures, forms a concave micro-honeycomb structure on the surface of the composite coating material, which further improves the comprehensive performance of the composite coating material, especially its wear resistance and temperature change resistance.

[0226] As can be seen from the comparison between Example 1 and Comparative Examples 5-11, the present invention has prepared a high-performance composite coating material by designing the specific constituent materials of the primer slurry, intermediate slurry and topcoat slurry.

[0227] In summary, this invention designs the structure of the composite coating material and the composition of each layer, and further designs the intermediate paint layer nested in the first fiber mesh and the topcoat layer nested in the second fiber mesh in the topcoat fiber mixture layer. By utilizing the nested structure of the fiber mesh and the paint layer, a composite coating material with high low-temperature resistance, wear resistance, salt spray resistance and temperature change resistance is prepared.

[0228] The applicant declares that the detailed structural features and detailed process flow of the present invention are illustrated through the above embodiments, but the present invention is not limited to the above detailed structural features and detailed process flow, that is, it does not mean that the present invention must rely on the above detailed structural features and detailed process flow to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the components used in the present invention, additions of auxiliary components, selection of specific methods, equivalent substitutions of the raw materials of the product of the present invention, additions of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A composite coating material, characterized in that, The composite coating material comprises a primer layer, an intermediate paint fiber mixture layer, and a topcoat fiber mixture layer stacked sequentially. The intermediate lacquer fiber mixture layer includes a first fiber mesh and an intermediate lacquer layer nested within the first fiber mesh; The topcoat fiber mixture layer includes a second fiber mesh and a topcoat layer nested within the second fiber mesh; the topcoat fiber mixture layer has a concave micro-honeycomb structure. The primer slurry forming the primer layer comprises the following components in parts by weight: 10-60 parts of epoxy modified nitrile latex A, 0.1-70 parts of modified zinc powder, and 0.1-80 parts of zinc phosphate; The intermediate paint slurry forming the intermediate paint layer comprises the following components in parts by weight: epoxy modified nitrile latex B 20-60 parts, hollow glass microspheres A 10-20 parts, silicon carbide 10-20 parts, titanium dioxide 5-10 parts, calcium carbonate 5-50 parts, and barium sulfate 10-100 parts. The topcoat slurry forming the topcoat layer comprises the following components in parts by weight: 30-70 parts of acrylic modified nitrile latex, 10-20 parts of hollow glass microspheres B, 10-20 parts of silicon carbide, 20-50 parts of titanium dioxide, 1-20 parts of carbon black, and 10-100 parts of barium sulfate. The raw materials for preparing the epoxy-modified nitrile butadiene latex A and the epoxy-modified nitrile butadiene latex B each independently include cross-linked epoxy emulsion, nitrile butadiene latex, lithium magnesium silicate, silane coupling agent, defoamer A and pH adjuster A; The mass ratio of the cross-linked epoxy emulsion to the nitrile latex is 10:90-80:20; Based on a total mass fraction of 100 parts for the cross-linked epoxy emulsion and the nitrile latex, the mass fraction of the magnesium lithium silicate is 0.03-0.6 parts, and the mass fraction of the silane coupling agent is 0.1-1 parts. The raw materials for preparing the acrylic modified nitrile latex include the following components in parts by weight: 1-50 parts of cross-linked acrylic emulsion, 50-90 parts of nitrile latex, 0.1-10 parts of alkali-swellable acrylic acid, 0.01-1 parts of defoamer B, 0.01-1 parts of pH adjuster B, and 0.1-5 parts of fluorinated silane coupling agent.

2. The composite coating material according to claim 1, characterized in that, Based on a total mass fraction of 100 parts for the cross-linked epoxy emulsion and the nitrile latex, the mass fraction of the defoamer A is 0.01-1 parts; the mass fraction of the pH adjuster A is 0.01-1 parts. The solid content of the cross-linked epoxy emulsion is 40-50%; The solid content of the nitrile latex is 35-50%; The silane coupling agent comprises any one or a combination of at least two of the following: γ-(2,3-epoxypropoxy)propyltrimethoxysilane, tridecafluorooctyltriethoxysilane, heptadecyltriethoxysilane, trifluoropropyltrimethoxysilane, fluorophenyltrimethoxysilane, fluoroalkylaminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, and γ-methacryloyloxypropyltrimethoxysilane. The epoxy-modified nitrile butadiene latex A and the epoxy-modified nitrile butadiene latex B are each prepared independently using the following method, which includes the following steps: After mixing cross-linked epoxy emulsion, defoamer A, and pH adjuster A, nitrile latex and lithium magnesium silicate are added sequentially, mixed, heated, and then silane coupling agent is added. The mixture is reacted, kept warm to defoam, and cooled to obtain epoxy modified nitrile latex A or epoxy modified nitrile latex B. The method for adding lithium magnesium silicate includes mixing lithium magnesium silicate and water to prepare a lithium magnesium silicate solution before adding it. The temperature after heating is 35-50℃; The method for adding the silane coupling agent includes dropwise addition; The reaction time is 1-3 hours; The heat preservation and degassing time is 20-28 hours.

3. The composite coating material according to claim 1, characterized in that, The solid content of the cross-linked acrylic emulsion is 35-50%; The solid content of the nitrile latex is 35-50%; The fluorinated silane coupling agent includes any one or a combination of at least two of the following: heptadecyltrimethoxysilane, tridecafluorooctyltriethoxysilane, trifluoropropyltrimethoxysilane, fluorophenyltrimethoxysilane, and fluoroalkylaminopropyltriethoxysilane. The acrylic-modified nitrile latex is prepared by the following method, which includes the following steps: After mixing cross-linked acrylic emulsion, defoamer B and pH adjuster B, nitrile latex and alkali-swellable acrylic acid are added sequentially, mixed, heated, and then a fluorosilane coupling agent is added. The mixture is reacted, kept warm to defoam, and cooled to obtain the acrylic-modified nitrile latex. The temperature after heating is 10-35℃; The reaction time is 3-5 hours; The heat preservation and degassing time is 20-28 hours.

4. The composite coating material according to claim 1, characterized in that, The average particle size of the hollow glass microspheres A and B is independently ≤0.5 mm; And / or, in the intermediate paint slurry, the mass ratio of hollow glass microspheres A to silicon carbide is (0.5-1):1; And / or, in the topcoat slurry, the mass ratio of hollow glass microspheres B to silicon carbide is (0.5-1):

1.

5. The composite coating material according to claim 1, characterized in that, The primer slurry, the intermediate slurry, and the topcoat slurry each independently further include the following components in parts by weight: 0.1-10 parts wetting and dispersing agent, 0.01-1 parts acid-base adjuster, 0.1-5 parts defoamer C, 0.1-1 parts leveling agent, 0.1-2 parts rust inhibitor, 0.1-10 parts film-forming aid, and 0-1 part defoamer; The primer, intermediate paint, and topcoat each independently include water.

6. The composite coating material according to claim 1, characterized in that, The viscosity of the primer slurry at 25°C is 80-120 KU; The viscosity of the intermediate paint slurry at 25°C is 80-120 KU; The viscosity of the topcoat slurry at 25°C is 80-120 KU.

7. The composite coating material according to claim 1, characterized in that, The first fiber mesh and the second fiber mesh are each independently selected from any one of glass fiber mesh, carbon fiber mesh, nylon fiber mesh, and ultra-high molecular weight polyethylene fiber mesh.

8. The composite coating material according to claim 1, characterized in that, The thickness of the primer layer is 30-100 μm; And / or, the thickness of the first fiber mesh is 50-500 μm, and the thickness of the intermediate paint layer is 30-100 μm; And / or, the thickness of the second fiber mesh is 50-500 μm, and the thickness of the topcoat layer is 20-100 μm.

9. The composite coating material according to claim 1, characterized in that, A first adhesive layer is also provided between the primer layer and the intermediate varnish fiber mixture layer; The thickness of the first adhesive layer is 10-300 μm; And / or, a second adhesive layer is further provided between the intermediate paint fiber mixture layer and the topcoat fiber mixture layer; The thickness of the second adhesive layer is 10-300 μm.

10. A method for preparing a composite coating material as described in any one of claims 1-9, characterized in that, The preparation method includes the following steps: (1) After spraying the primer onto the substrate, a first fiber mesh is set up and dried to form a film; (2) After spraying the intermediate paint slurry on the side of the first fiber mesh away from the substrate, the second fiber mesh is set and dried to form a film; (3) On the side of the second fiber mesh away from the substrate, spray the topcoat slurry and dry it to form a film to obtain the composite coating material.

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