A method for preparing a marine anti-rust coating

Abstract

The application relates to the technical field of paint production, in particular to a preparation method of a ship rust-proof paint, which comprises the following steps: (1) preparing a primer: surface modification treatment of nano zinc oxide and graphene nanosheets is carried out by using a silane coupling agent, and then the nano zinc oxide and the graphene nanosheets are uniformly mixed with a base material, and the primer is obtained; (2) preparing a topcoat: the base material is uniformly mixed with antifouling microcapsules, and the topcoat is obtained. Modified nano cuprous oxide and methyl silicone oil are used as core materials, urea-formaldehyde resin is wrapped on the surfaces of the core materials to form a capsule shell, the antifouling microcapsules are uniformly distributed in a paint matrix, an ultramicron structure is formed, the hydrophobic capacity is improved by cooperation of slowly-released silicone oil, the sailing resistance of a ship is reduced, the modified nano cuprous oxide in the antifouling microcapsules is slowly released by gradual rupture of the antifouling microcapsules, the phenomenon of copper burst release is prevented, long-term antifouling effect of a coating can be realized, and the service life of the coating is prolonged.

Description

Technical Field

[0001] This invention relates to the field of coating production technology, specifically to a method for preparing a marine anti-rust coating. Background Technology

[0002] The study of corrosion prevention in steel has increasingly attracted attention. Among various corrosion prevention technologies, coating corrosion prevention technology is the most widely used because it is easy to apply, has wide adaptability, is not limited by the area or shape of the equipment, and has low costs for recoating and repair. In the marine shipbuilding industry, preventing marine biofouling and ship corrosion has always been a major challenge. With the rapid development of marine shipping and the continuous exploitation of marine resources, the harm caused by marine biofouling is becoming increasingly prominent. Traditional antifouling and anticorrosion coatings use cuprous oxide to inhibit the attachment and growth of marine organisms. However, when cuprous oxide is directly added to the coating matrix for mixing and spraying, the ship coating will experience an initial "explosive release" phenomenon, resulting in a large loss of copper ions in the early stages. The amount of copper ions released later is limited, making it difficult to achieve long-term antifouling and anticorrosion protection for ships. Based on this, a method for preparing a marine anti-rust coating is proposed. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention provides a method for preparing a marine anti-rust coating, achieving a long-term anti-fouling effect, extending the service life of the coating, and reducing the bioburden on the ship's surface.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing a marine anti-rust coating, comprising the following steps,

[0005] (1) Preparation of primer: The surface of nano zinc oxide and graphene nanosheets is modified by using silane coupling agent, and then mixed evenly with the base material to obtain the primer.

[0006] (2) Preparation of topcoat: Mix the base material and antifouling microcapsules evenly to obtain the topcoat.

[0007] Preferably, in step (1), the mass ratio of nano-zinc oxide to graphene nanosheets is (2-5):1; and nano-zinc oxide accounts for 5-10% of the mass of the base material.

[0008] Preferably, in step (2), the antifouling microcapsules account for 10-20% of the mass of the base material.

[0009] Preferably, in step (2), the antifouling microcapsules are prepared as follows: S1, the surface of nano-cuprous oxide is modified with a silane coupling agent, poured into a 1wt% dodecyl dimethyl benzyl ammonium chloride solution, stirred continuously for 2h, then filtered, washed and dried to obtain modified nano-cuprous oxide; S2, Tween-80, methyl silicone oil and modified nano-cuprous oxide are added to deionized water and mechanically emulsified to obtain an emulsion; S3, the pH of the emulsion is adjusted to 8.5, and then urea, 37wt% formaldehyde solution, ammonium chloride and resorcinol are added, and the reaction is kept at 55℃ for 4h, and then the pH is adjusted to 7 to obtain a reaction solution; S4, the reaction solution is cooled, filtered and dried to obtain antifouling microcapsules.

[0010] Preferably, in step S1, the mass ratio of nano-cuprous oxide to dodecyl dimethyl benzyl ammonium chloride is 5:1.

[0011] Preferably, in steps S2-S3, the mass ratio of Tween-80, methyl silicone oil, modified nano cuprous oxide, urea, 37wt% formaldehyde solution, ammonium chloride and resorcinol is 1:18:18:10:25:1:1; and the material-to-liquid ratio of modified nano cuprous oxide and deionized water is 1:30 g / ml.

[0012] Preferably, in steps (1) and (2), the base material comprises the following raw materials by mass percentage: 0.5-1% of defoamer (YCK-615), 0.2-0.5% of leveling agent (YCK-1330), 0.1-0.5% of dispersant (YCK-2110), 5-10% of calcium petroleum sulfonate, and the balance being a modified polyacrylate copolymer solution.

[0013] Preferably, the modified polyacrylate copolymer solution is prepared as follows: methyl isobutyl ketone is added to a reactor and the temperature is raised to 75°C; dodecafluoroheptyl methacrylate, butyl acrylate, glycidyl methacrylate and γ-methacryloyloxypropyltrimethoxysilane are added to the reactor, and after stirring evenly, azobisisobutyronitrile is added, and the mixture is kept at the temperature for 3 hours to obtain the final product.

[0014] Preferably, the mass ratio of dodecafluoroheptyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane, glycidyl methacrylate, butyl acrylate, methyl isobutyl ketone and azobisisobutyronitrile is 4:3:12:12:30:0.2.

[0015] The anti-rust coating for ships prepared in this invention consists of a primer and a topcoat. When using it, the primer is first sprayed onto the surface of the ship, and after drying, the topcoat is sprayed onto the primer surface and then dried.

[0016] This invention provides a method for preparing a marine anti-rust coating, which has the following advantages compared with the prior art:

[0017] Beneficial effects:

[0018] This invention uses modified nano-cuprous oxide and methyl silicone oil as core materials, and encapsulates them with urea-formaldehyde resin as a shell. The resulting antifouling microcapsules are uniformly distributed in the coating matrix, forming an ultramicron structure. Combined with the slowly released silicone oil, this improves hydrophobicity and reduces the ship's navigation resistance. Furthermore, the gradual rupture of the antifouling microcapsules slowly releases the modified nano-cuprous oxide inside, preventing the "explosive release" of copper and achieving a long-term antifouling effect for the coating, thus extending the coating's service life.

[0019] This invention uses a silane coupling agent to modify the surface of nano-cuprous oxide, allowing it to be uniformly dispersed in a quaternary ammonium salt solution. This allows the quaternary ammonium salt to combine with the nano-cuprous oxide, forming a composite antifouling agent that can further improve the antifouling and sterilization effect, thereby reducing the bioburden on the ship's surface.

[0020] The coating used in this invention consists of a primer and a topcoat. The primer adheres to the ship's body and serves as a rust preventer, while the topcoat acts on the surface of the primer, forming a protective barrier for the primer and also providing good anti-fouling properties. By combining the primer and topcoat, the rust and anti-fouling effects of the coating are improved. Detailed Implementation

[0021] The following embodiments are provided to illustrate the implementation of this application in detail, so that the process of how this application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0022] Example 1

[0023] The antifouling microcapsules were prepared as follows:

[0024] S1. The surface of nano-cuprous oxide was modified by using silane coupling agent KH560. The modified nano-cuprous oxide was poured into a 1 wt% dodecyl dimethyl benzyl ammonium chloride solution and stirred continuously for 2 h. Then it was filtered, washed and dried to obtain modified nano-cuprous oxide. The mass ratio of nano-cuprous oxide to dodecyl dimethyl benzyl ammonium chloride was 5:1.

[0025] S2. Add Tween-80, methyl silicone oil and modified nano cuprous oxide to deionized water and perform mechanical emulsification to obtain an emulsion;

[0026] S3. Adjust the pH of the emulsion to 8.5, then add urea, 37wt% formaldehyde solution, ammonium chloride and resorcinol, keep the reaction at 55℃ for 4 hours, and then adjust the pH to 7 to obtain the reaction solution.

[0027] The mass ratio of Tween-80, methyl silicone oil, modified nano cuprous oxide, urea, 37wt% formaldehyde solution, ammonium chloride and resorcinol is 1:18:18:10:25:1:1; the material-to-liquid ratio of modified nano cuprous oxide and deionized water is 1:30 g / ml.

[0028] S4. Cool, filter, and dry the reaction solution to obtain antifouling microcapsules.

[0029] Example 2

[0030] The modified polyacrylate copolymer solution was prepared as follows: methyl isobutyl ketone was added to a reactor and the temperature was raised to 75°C; dodecyl fluoroheptyl methacrylate, butyl acrylate, glycidyl methacrylate, and γ-methacryloyloxypropyltrimethoxysilane were added to the reactor, stirred until homogeneous, and then azobisisobutyronitrile was added. The mixture was kept at this temperature for 3 hours to obtain the final product. The mass ratio of dodecyl fluoroheptyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane, glycidyl methacrylate, butyl acrylate, methyl isobutyl ketone, and azobisisobutyronitrile was 4:3:12:12:30:0.2.

[0031] Example 3

[0032] A method for preparing a marine anti-rust coating includes the following steps:

[0033] (1) Preparation of primer: The surface of nano zinc oxide and graphene nanosheets was modified by using silane coupling agent KH-550, and then mixed evenly with the base material to obtain the primer; the mass ratio of nano zinc oxide to graphene nanosheets was 5:1; the nano zinc oxide accounted for 5% of the mass of the base material.

[0034] (2) Preparation of topcoat: Mix the base material and the antifouling microcapsules in Example 1 evenly, with the antifouling microcapsules accounting for 20% of the mass of the base material, and the topcoat is obtained.

[0035] By mass percentage, the above base material comprises the following raw materials: 0.5% YCK-615 defoamer, 0.5% YCK-1330 leveling agent, 0.1% YCK-2110 dispersant, 10% calcium petroleum sulfonate, and the balance being the modified polyacrylate copolymer solution in Example 2.

[0036] Example 4

[0037] A method for preparing a marine anti-rust coating includes the following steps:

[0038] (1) Preparation of primer: The surface of nano zinc oxide and graphene nanosheets was modified by using silane coupling agent KH-560, and then mixed evenly with the base material to obtain the primer; the mass ratio of nano zinc oxide to graphene nanosheets was 2:1; the nano zinc oxide accounted for 10% of the mass of the base material.

[0039] (2) Preparation of topcoat: Mix the base material and the antifouling microcapsules in Example 1 evenly, with the antifouling microcapsules accounting for 10% of the mass of the base material, and the topcoat is obtained.

[0040] By mass percentage, the above base material comprises the following raw materials: 1% YCK-615 defoamer, 0.2% YCK-1330 leveling agent, 0.5% YCK-2110 dispersant, 5% calcium petroleum sulfonate, and the balance being the modified polyacrylate copolymer solution in Example 2.

[0041] Example 5

[0042] A method for preparing a marine anti-rust coating includes the following steps:

[0043] (1) Preparation of primer: The surface of nano zinc oxide and graphene nanosheets was modified by using silane coupling agent KH-570, and then mixed evenly with the base material to obtain the primer; the mass ratio of nano zinc oxide to graphene nanosheets was 3:1; the nano zinc oxide accounted for 8% of the mass of the base material.

[0044] (2) Preparation of topcoat: Mix the base material and the antifouling microcapsules in Example 1 evenly, with the antifouling microcapsules accounting for 15% of the mass of the base material, and the topcoat is obtained.

[0045] By mass percentage, the above base material comprises the following raw materials: 0.6% YCK-615 defoamer, 0.3% YCK-1330 leveling agent, 0.2% YCK-2110 dispersant, 8% calcium petroleum sulfonate, and the balance being the modified polyacrylate copolymer solution in Example 2.

[0046] Comparative Example 1

[0047] A method for preparing a marine anti-rust coating is basically the same as that in Example 5, except that the antifouling capsule in Example 1 is replaced with the modified nano-cuprous oxide prepared in Example 1.

[0048] Comparative Example 2

[0049] A method for preparing a marine anti-rust coating is basically the same as that in Example 5, except that the antifouling capsule in Example 1 is replaced with untreated nano-cuprous oxide.

[0050] Comparative Example 3

[0051] A method for preparing a marine anti-rust coating involves uniformly mixing a base material with antifouling microcapsules from Example 1, wherein the antifouling microcapsules account for 15% of the mass of the base material.

[0052] By mass percentage, the above base material comprises the following raw materials: 0.6% YCK-615 defoamer, 0.3% YCK-1330 leveling agent, 0.2% YCK-2110 dispersant, 8% calcium petroleum sulfonate, and the balance being the modified polyacrylate copolymer solution in Example 2.

[0053] Quality Inspection

[0054] 1. Using the coatings in Examples 3-5 and Comparative Examples 1-3 as samples, the antifouling performance and water resistance of the coating films were tested according to GB / T5370-2007 "Antifouling Paint Samples Shallow Sea Immersion Test Method". The test period was 12 months. The specific results are shown in the table below.

[0055] Table 1 Antifouling performance

[0056] category Physical state of topcoat film (%) Biodiversity cover (%) <![CDATA[Biomass (g / cm 2 )]]> Example 3 The area of ​​peeling is 0.35. 0.27 0.022 Example 4 The area of ​​peeling is 0.41. 0.56 0.026 Example 5 The area of ​​peeling is 0.22. 0.12 0.017 Comparative Example 1 The area of ​​peeling is 5.85. 4.84 0.106 Comparative Example 2 The area of ​​peeling is 6.24. 7.21 0.143 Comparative Example 3 The area of ​​peeling is 0.28. 0.18 0.019

[0057] As can be seen from the table above, the peeling area of ​​the topcoat in Comparative Examples 1-2 is relatively large because a "burst release" phenomenon occurs in the early stage, resulting in excessive release of modified nano cuprous oxide or nano cuprous oxide, which leads to more topcoat peeling, shortens the service life, and also affects the anti-fouling performance in the later stage.

[0058] 2. Using the coatings from Examples 3-5 and Comparative Examples 1-2 as samples, a primer was first sprayed onto a low-carbon steel plate and dried (referred to as the control plate), followed by a topcoat sprayed and dried to obtain the corresponding samples. The drag reduction efficiency of the control plate and each sample was tested using a HAKKE RS6000 rotational rheometer. The specific test results are shown in the table below.

[0059] Table 2 Drag Reduction Efficiency

[0060]

[0061]

[0062] As can be seen from the table above, the drag reduction efficiency of the samples in Comparative Examples 1-2 is significantly lower than that of the samples in Examples 3-5, indicating that the use of antifouling microcapsules can greatly improve the drag reduction effect.

[0063] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a marine anti-rust coating, characterized in that, Includes the following steps, (1) Preparation of primer: The surface of nano zinc oxide and graphene nanosheets is modified by using silane coupling agent, and then mixed evenly with the base material to obtain the primer. (2) Preparation of topcoat: Mix the base material and antifouling microcapsules evenly to obtain the topcoat; In step (2), the antifouling microcapsules are prepared as follows: S1. The surface of nano-cuprous oxide was modified by using a silane coupling agent. The nano-cuprous oxide was poured into a 1 wt% dodecyl dimethyl benzyl ammonium chloride solution and stirred continuously for 2 hours. Then it was filtered, washed and dried to obtain modified nano-cuprous oxide. S2. Add Tween-80, methyl silicone oil and modified nano cuprous oxide to deionized water and perform mechanical emulsification to obtain an emulsion; S3. Adjust the pH of the emulsion to 8.5, then add urea, 37wt% formaldehyde solution, ammonium chloride and resorcinol, keep the reaction at 55℃ for 4 hours, and then adjust the pH to 7 to obtain the reaction solution. S4. Cool the reaction solution, filter it, and dry it to obtain antifouling microcapsules; In step S1, the mass ratio of nano-cuprous oxide to dodecyl dimethyl benzyl ammonium chloride is 5:1; In steps S2-S3, the mass ratio of Tween-80, methyl silicone oil, modified nano cuprous oxide, urea, 37wt% formaldehyde solution, ammonium chloride and resorcinol is 1:18:18:10:25:1:1; the material-to-liquid ratio of modified nano cuprous oxide and deionized water is 1:30 g / ml.

2. The method for preparing the marine anti-rust coating according to claim 1, characterized in that, In step (1), the mass ratio of nano zinc oxide to graphene nanosheets is (2-5):1; nano zinc oxide accounts for 5-10% of the mass of the base material.

3. The method for preparing the marine anti-rust coating according to claim 1, characterized in that, In step (2), the antifouling microcapsules account for 10-20% of the mass of the base material.

4. The method for preparing the marine anti-rust coating according to claim 1, characterized in that, In steps (1) and (2), the base material comprises the following raw materials by mass percentage: 0.5-1% defoamer, 0.2-0.5% leveling agent, 0.1-0.5% dispersant, 5-10% calcium petroleum sulfonate, and the balance being a modified polyacrylate copolymer solution.

5. The method for preparing the marine anti-rust coating according to claim 4, characterized in that, The modified polyacrylate copolymer solution was prepared as follows: methyl isobutyl ketone was added to the reactor and the temperature was raised to 75°C; dodecafluoroheptyl methacrylate, butyl acrylate, glycidyl methacrylate and γ-methacryloyloxypropyltrimethoxysilane were added to the reactor and stirred evenly. Then azobisisobutyronitrile was added and the mixture was kept at the temperature for 3 hours to obtain the final product.

6. The method for preparing the marine anti-rust coating according to claim 5, characterized in that, The mass ratio of dodecafluoroheptyl methacrylate, γ-methacryloyloxypropyltrimethoxysilane, glycidyl methacrylate, butyl acrylate, methyl isobutyl ketone, and azobisisobutyronitrile is 4:3:12:12:30:0.

2.

7. An application of a marine anti-rust coating prepared by any one of the preparation methods described in claims 1-6, specifically comprising: spraying a primer onto the surface of the ship, drying it, spraying a topcoat onto the primer surface, and continuing to dry it.

Images