Inorganic zinc-rich coating as well as preparation method and application thereof

Abstract

The invention relates to an inorganic zinc-rich coating as well as a preparation method and application thereof, and relates to the technical field of coatings, the inorganic zinc-rich coating comprises a component A and a component B, the component A comprises the following raw materials in parts by weight: 75-85 parts of a silicate solution and 0.5-2 parts of an auxiliary agent; the component B is prepared from the following raw materials in parts by weight: 10 to 20 parts of modified zinc powder and 25 to 35 parts of zinc powder; the modified zinc powder is obtained by carrying out composite modification on zinc powder by adopting a pyridine crown ether ring compound and an amino silane coupling agent; the silicate solution is prepared by compounding a lithium silicate solution and a potassium silicate solution, the modulus of lithium silicate is 3-5, and the modulus of potassium silicate is 5-6.5. According to the inorganic zinc-rich coating, the silicate solution with the proper modulus serves as a base material, meanwhile, the specific modified zinc powder is introduced, the anti-sliding performance, the adhesive force and other performance of the inorganic zinc-rich coating are remarkably improved, and the use requirements of steel structures such as high-strength bolts can be met.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to an inorganic zinc-rich coating and a preparation method and application thereof. Background Art

[0002] As one of the main connection forms of welded steel structures, high-strength bolt connection has the advantages of good stress performance, fatigue resistance, good seismic performance, high connection stiffness and simple construction. Therefore, it has been widely used in the construction site connection of building steel structures and bridge steel structures. For the connection of high-strength bolts, the anti-slip coefficient of the contact friction surface of the connection plate is an important factor affecting the connection bearing capacity. When the specifications and quantity of the connecting bolts are determined, the treatment method of the friction surface and the anti-slip coefficient value become the main parameters for determining the connection bearing capacity of the friction surface. Therefore, in the construction of high-strength bolt connections, the treatment of the friction surface of the connection plate is crucial.

[0003] However, the anti-corrosion coatings currently used for steel structures and high-strength bolts have many shortcomings. First, the anti-slip coefficient is low. The anti-slip coefficients of products on the market are mostly in the range of 0.35 to 0.50, which cannot meet the industry standard requirement of an initial anti-slip coefficient of the coating of ≥0.55. Secondly, traditional inorganic zinc-rich coatings have strong shrinkage stress during the film-forming process, resulting in poor film-forming properties and a rapid attenuation rate of the anti-slip coefficient (industry standards require that the anti-slip coefficient of the coating be ≥0.45 after 6 months of outdoor use), and the film has low adhesion after formation and is easy to fall off, which cannot provide long-lasting and stable protection for high-strength bolts. Summary of the invention

[0004] In order to solve the above problems, the present invention provides an inorganic zinc-rich coating and a preparation method and application thereof.

[0005] In a first aspect, the present invention provides an inorganic zinc-rich coating, wherein the inorganic zinc-rich coating comprises a component A and a component B;

[0006] In parts by weight, the component A comprises the following raw materials: 75-85 parts of silicate solution and 0.5-2 parts of auxiliary agent;

[0007] In parts by weight, the B component includes the following raw materials: 10 to 20 parts of modified zinc powder and 25 to 35 parts of zinc powder;

[0008] The modified zinc powder is obtained by composite-modifying zinc powder with pyridine crown ether ring compounds and aminosilane coupling agents;

[0009] The silicate solution is obtained by compounding a lithium silicate solution and a potassium silicate solution. The modulus of the lithium silicate is 3-5, and the modulus of the potassium silicate is 5-6.5.

[0010] Furthermore, the weight ratio of the component A to the component B is 1:(1.8-2.3).

[0011] Furthermore, in parts by weight, the component A comprises the following raw materials: 80 parts of silicate solution and 1.5 parts of additives; in parts by weight, the component B comprises the following raw materials: 15 parts of modified zinc powder and 30 parts of zinc powder.

[0012] Furthermore, the weight ratio of the lithium silicate solution to the potassium silicate solution is (1-2):(5-8); in terms of weight percentage, the solid content of the lithium silicate solution is 19-24%; in terms of weight percentage, the solid content of the potassium silicate solution is 24-26%.

[0013] Furthermore, the preparation method of the modified zinc powder comprises the following process:

[0014] 2,2'-Bipyridine-5,5'-dicarboxaldehyde was first stirred with trifluoromethanesulfonic acid, then filtered and recrystallized to obtain 2H + -BPDA;

[0015] The 2H + -BPDA and dibenzo-24-crown-8 are stirred for a second time, and then the solvent is removed to obtain the pyridine crown ether ring compound;

[0016] Adding the aminosilane coupling agent and zinc powder into anhydrous ethanol for a third stirring, then adding the pyridine crown ether ring compound for a fourth stirring, filtering, washing and drying to obtain the modified zinc powder;

[0017] The molar ratio of the 2,2'-bipyridine-5,5'-dicarboxaldehyde to the trifluoromethanesulfonic acid is (0.45-0.50): (1.1-1.3); the 2H + -BPDA and the dibenzo-24-crown ether-8 have a molar ratio of 1:1; the weight ratio of the pyridine crown ether ring compound, the aminosilane coupling agent, the zinc powder and the anhydrous ethanol is (1-1.5):(0.5-1):(2.2-3):(10-20).

[0018] Furthermore, the working condition parameters of the first stirring include: temperature of 0 to 5°C, stirring time of 3.5 to 5 hours; the working condition parameters of the second stirring include: temperature of room temperature, stirring time of 20 to 30 hours; the working condition parameters of the third stirring include: temperature of 50 to 60°C, stirring time of 1 to 2 hours; the working condition parameters of the fourth stirring include: temperature of 50 to 60°C, stirring time of 1 to 2 hours; the aminosilane coupling agent includes at least one of N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and 3-aminopropyltrimethoxysilane.

[0019] Furthermore, the auxiliary agent is composed of a thickener and a defoamer in a weight ratio of (3-5):1; and the particle size of the zinc powder is 500-800 meshes.

[0020] In a second aspect, the present invention provides a method for preparing the inorganic zinc-rich coating according to any one of the first aspects, the preparation method comprising the following steps:

[0021] Stirring and mixing the raw materials in component A to obtain component A;

[0022] The raw materials in component B are added to component A and stirred to obtain the inorganic zinc-rich coating.

[0023] In a third aspect, the present invention provides a use of the inorganic zinc-rich coating described in any one of the first aspect and the second aspect in treating a bolt connection surface.

[0024] The above technical solution provided by the embodiment of the present invention has at least the following advantages compared with the prior art:

[0025] The embodiment of the present invention provides an inorganic zinc-rich coating and a preparation method and application thereof. The present invention uses a silicate solution with a suitable modulus as a base material and introduces a specific modified zinc powder, thereby significantly improving the anti-slip performance and adhesion of the inorganic zinc-rich coating, and can meet the use requirements of steel structures such as high-strength bolts. Specifically:

[0026] 1. The role of silicate solution

[0027] Film-forming properties: Silicate solution is the main film-forming substance of inorganic zinc-rich coatings, and has good matching properties with the raw materials in component B, forming a network polymer coating to obtain a solid protective coating to protect the substrate from corrosion.

[0028] Improved adhesion: The silicate solution has good adhesion to the metal surface, which is due to the chemical bonding between the silicate and the metal surface. At the same time, the silicate solution can also react chemically with the modified zinc powder and zinc powder to further enhance the adhesion of the coating.

[0029] Anti-slip performance: Lithium silicate and potassium silicate in the silicate solution have a suitable modulus and can form a coating surface with a certain roughness and friction, thereby improving the anti-slip performance of the coating.

[0030] 2. The role of modified zinc powder

[0031] Anti-rust and anti-corrosion: The modified zinc powder is composite-modified with pyridine crown ether ring compounds and aminosilane coupling agents, so that a dense protective film is formed on the surface of the zinc powder, which effectively blocks the invasion of water molecules and corrosive media, thereby playing a role in anti-rust and anti-corrosion.

[0032] Enhanced adhesion: The modified zinc powder has good compatibility and reactivity with the silicate solution, and can form a strong chemical bond to further enhance the adhesion of the coating.

[0033] Improved anti-slip performance: The addition of modified zinc powder can also improve the anti-slip performance of the coating. This is because the introduction of a special pyridine crown ether ring structure has a certain steric hindrance, which makes the modified zinc powder form microscopic ridges and undulations in the coating, increasing the roughness and friction of the coating surface, further improving the anti-slip performance.

[0034] 3. The role of zinc powder

[0035] Electrochemical protection: Zinc powder, as the main anti-corrosion component of inorganic zinc-rich coatings, can provide electrochemical protection. Since zinc is more active than iron and has a more negative potential than iron, zinc atoms are prone to lose electrons in electrolyte solutions, thereby protecting steel from corrosion.

[0036] Improved adhesion: Zinc powder can react chemically with silicate solution and modified zinc powder to form a strong chemical bond, which helps to improve the adhesion of the coating.

[0037] 4. The role of additives

[0038] Improve construction performance: Additives can improve the viscosity of the coating, improve the defoaming, wettability and leveling properties of the coating, thereby improving the construction performance of the coating.

[0039] Enhance film-forming properties: Additives can also promote the hydrolysis and polycondensation reactions of silicate solutions, accelerate the formation and curing process of coatings, and improve the film-forming properties of coatings.

[0040] In summary, the present invention uses silicate solution with suitable modulus as the base material, introduces specific modified zinc powder and zinc powder as anti-corrosion components, and uses additives to improve construction performance and film-forming performance, thereby significantly improving the comprehensive performance of inorganic zinc-rich coatings such as anti-slip performance and adhesion, and is particularly suitable for high-strength bolt connection surface treatment of steel components such as bridges and prefabricated buildings. Its excellent performance can effectively protect the connection surface from corrosion and wear, provide long-lasting and stable protection for high-strength bolts, and thus improve the service life and safety of the connection surface. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0043] In a first aspect, the present invention provides an inorganic zinc-rich coating, wherein the inorganic zinc-rich coating comprises a component A and a component B;

[0044] In parts by weight, the component A comprises the following raw materials: 75-85 parts of silicate solution and 0.5-2 parts of auxiliary agent;

[0045] In parts by weight, the B component includes the following raw materials: 10 to 20 parts of modified zinc powder and 25 to 35 parts of zinc powder;

[0046] The modified zinc powder is obtained by composite-modifying zinc powder with pyridine crown ether ring compounds and aminosilane coupling agents;

[0047] The silicate solution is obtained by compounding a lithium silicate solution and a potassium silicate solution. The modulus of the lithium silicate is 3-5, and the modulus of the potassium silicate is 5-6.5.

[0048] An embodiment of the present invention provides an inorganic zinc-rich coating. The present invention uses a silicate solution with a suitable modulus as a base material and introduces specific modified zinc powder, thereby significantly improving the anti-slip performance and adhesion of the inorganic zinc-rich coating, and can meet the use requirements of steel structures such as high-strength bolts.

[0049] In some specific embodiments, the silicate solution can be directly compounded using commercial products such as Zhejiang Yuda Chemical Co., Ltd., Hubei Xinyuhong Biomedical Technology Co., Ltd., Wuhan Jiyesheng Chemical Co., Ltd., etc.; or it can be homemade according to the existing silicate preparation process, and then compounded by adding water. Preferably, the modulus of the lithium silicate is 4.8, and the modulus of the potassium silicate is 5.6.

[0050] In some specific embodiments, the weight ratio of the component A to the component B is 1:(1.8-2.3), preferably 1:2.

[0051] In some specific embodiments, the component A includes the following raw materials, by weight: 80 parts of silicate solution and 1.5 parts of additives; the component B includes the following raw materials, by weight: 15 parts of modified zinc powder and 30 parts of zinc powder.

[0052] In some specific embodiments, the weight ratio of the lithium silicate solution to the potassium silicate solution is (1-2):(5-8), preferably 1.5:7; in terms of weight percentage, the solid content of the lithium silicate solution is 19-24%, preferably 22%; in terms of weight percentage, the solid content of the potassium silicate solution is 24-26%, preferably 25%.

[0053] In some specific embodiments, the method for preparing the modified zinc powder includes the following process:

[0054] 2,2'-Bipyridine-5,5'-dicarboxaldehyde was first stirred with trifluoromethanesulfonic acid, then filtered and recrystallized to obtain 2H + -BPDA;

[0055] The 2H + -BPDA and dibenzo-24-crown-8 are stirred for a second time, and then the solvent is removed to obtain the pyridine crown ether ring compound;

[0056] Adding the aminosilane coupling agent and zinc powder into anhydrous ethanol for a third stirring, then adding the pyridine crown ether ring compound for a fourth stirring, filtering, washing and drying to obtain the modified zinc powder;

[0057] The molar ratio of the 2,2'-bipyridine-5,5'-dicarboxaldehyde to the trifluoromethanesulfonic acid is (0.45-0.50):(1.1-1.3), preferably 0.47:1.2; + -BPDA and the dibenzo-24-crown ether-8 have a molar ratio of 1:1; the weight ratio of the pyridine crown ether ring compound, the aminosilane coupling agent, the zinc powder and the anhydrous ethanol is (1-1.5):(0.5-1):(2.2-3):(10-20).

[0058] In some specific embodiments, the working condition parameters of the first stirring include: temperature of 0-5°C, which can be operated in an ice water bath environment; the stirring time is 3.5-5 hours; the working condition parameters of the second stirring include: temperature of room temperature, and stirring time of 20-30 hours; the working condition parameters of the third stirring include: temperature of 50-60°C, and stirring time of 1-2 hours; the working condition parameters of the fourth stirring include: temperature of 50-60°C, and stirring time of 1-2 hours; the aminosilane coupling agent includes at least one of N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and 3-aminopropyltrimethoxysilane.

[0059] In some specific embodiments, the auxiliary agent is composed of a thickener and a defoamer in a weight ratio of (3 to 5): 1. The thickener can be directly commercially available, such as a polyurethane thickener such as PU-40, and the defoamer can be directly commercially available, such as BYK-1789 silicone defoamer; the particle size of the zinc powder is 500 to 800 mesh.

[0060] In a second aspect, based on the same inventive concept, the present invention provides a method for preparing the inorganic zinc-rich coating according to any one of the first aspects, the preparation method comprising the following steps:

[0061] Stirring and mixing the raw materials in component A to obtain component A;

[0062] The raw materials in component B are added to component A and stirred to obtain the inorganic zinc-rich coating.

[0063] The preparation method of the inorganic zinc-rich coating of the present invention is simple to operate, does not require additional specific equipment, and is suitable for batch industrial production. At the same time, the preparation method is based on the inorganic zinc-rich coating described in any one of the first aspects, so it has at least the beneficial effects described in any one of the first aspects, which will not be repeated here.

[0064] In a third aspect, based on the same inventive concept, the present invention provides the use of the inorganic zinc-rich coating described in any one of the first aspect and the second aspect in treating bolt connection surfaces.

[0065] The inorganic zinc-rich coating provided by the present invention has excellent anti-slip performance and adhesion and other properties, and is particularly suitable for high-strength bolt connection surface treatment of steel components such as bridges and prefabricated buildings. Its excellent performance can effectively protect the connection surface from corrosion and wear, and provide long-lasting and stable protection for high-strength bolts, thereby improving the service life and safety of the connection surface.

[0066] It should be noted that the inorganic zinc-rich coating provided in the embodiments of the present invention and the component raw materials involved in the preparation method and application thereof, unless otherwise specified or specified, can be directly commercially available products or homemade using existing public preparation methods; at the same time, the steps and parameters involved, unless otherwise specified or specified, can be carried out according to the existing inorganic zinc-rich coating processing technology or directly using existing equipment, and the present invention document will not repeat them one by one.

[0067] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are intended only to illustrate the present invention and are not intended to limit the scope of the present invention. The experimental methods in the following examples that do not specify specific conditions are usually measured according to national standards. If there is no corresponding national standard, then the conditions recommended by the manufacturer are followed.

[0068] Example 1

[0069] This example provides an inorganic zinc-rich coating, wherein the inorganic zinc-rich coating comprises component A and component B in a weight ratio of 1:2;

[0070] In parts by weight, the component A comprises the following raw materials: 80 parts of silicate solution and 1.5 parts of auxiliary agent;

[0071] In parts by weight, the B component includes the following raw materials: 15 parts of modified zinc powder and 30 parts of zinc powder;

[0072] The modified zinc powder is obtained by composite-modifying zinc powder with pyridine crown ether ring compounds and aminosilane coupling agents;

[0073] The silicate solution is obtained by compounding a lithium silicate solution and a potassium silicate solution in a weight ratio of 1.5:7; the modulus of the lithium silicate is 4.8, and the modulus of the potassium silicate is 5.6; in terms of weight percentage, the solid content of the lithium silicate solution is 22%; in terms of weight percentage, the solid content of the potassium silicate solution is 25%;

[0074] The auxiliary agent is composed of a thickener and a defoamer in a weight ratio of 4:1;

[0075] The particle size of the zinc powder is 700 mesh;

[0076] The preparation method of the modified zinc powder comprises the following process:

[0077] 2,2'-bipyridine-5,5'-dicarboxaldehyde was dissolved in dichloromethane solvent, and then stirred in an ice-water bath for 15 minutes; then trifluoromethanesulfonic acid dissolved in dichloromethane was added dropwise to the reaction system, and stirred for 4 hours, wherein the molar ratio of the 2,2'-bipyridine-5,5'-dicarboxaldehyde to the trifluoromethanesulfonic acid was 0.47:1.2; after the reaction was completed, a light yellow solid was obtained by filtration, and then recrystallized in acetonitrile and ether to obtain 2H + -BPDA (white solid);

[0078] The 2H + -BPDA and dibenzo-2,4-crown-8 were added to ethanol and stirred at room temperature for 24 hours, then the solvent was removed by rotary evaporation and dried to obtain the pyridine crown ether ring compound (yellow solid);

[0079] An aminosilane coupling agent (specifically N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane) and zinc powder are added to anhydrous ethanol, stirred at 55°C for 1.5 hours, and then the pyridine crown ether ring compound is added and continued to be stirred at 55°C for 1.5 hours, filtered, washed and dried to obtain the modified zinc powder; wherein the weight ratio of the pyridine crown ether ring compound, the aminosilane coupling agent, the zinc powder and the anhydrous ethanol is 1.2:0.8:2.5:15.

[0080] The preparation method of the above-mentioned inorganic zinc-rich coating comprises the following steps:

[0081] Stirring and mixing the raw materials in component A to obtain component A;

[0082] The raw materials in component B are added to component A and stirred to obtain the inorganic zinc-rich coating.

[0083] Example 2

[0084] This example provides an inorganic zinc-rich coating, wherein the inorganic zinc-rich coating comprises component A and component B in a weight ratio of 1:1.8;

[0085] In parts by weight, the component A includes the following raw materials: 75 parts of silicate solution and 0.5 parts of auxiliary agent;

[0086] In parts by weight, the B component includes the following raw materials: 10 parts of modified zinc powder and 35 parts of zinc powder;

[0087] The modified zinc powder is obtained by composite-modifying zinc powder with pyridine crown ether ring compounds and aminosilane coupling agents;

[0088] The silicate solution is obtained by compounding a lithium silicate solution and a potassium silicate solution in a weight ratio of 1:8; the modulus of the lithium silicate is 4.8, and the modulus of the potassium silicate is 6.5; in terms of weight percentage, the solid content of the lithium silicate solution is 19%; in terms of weight percentage, the solid content of the potassium silicate solution is 25%;

[0089] The auxiliary agent is composed of a thickener and a defoamer in a weight ratio of 3:1;

[0090] The particle size of the zinc powder is 500 mesh;

[0091] The preparation method of the modified zinc powder comprises the following process:

[0092] 2,2'-bipyridine-5,5'-dicarboxaldehyde was dissolved in dichloromethane solvent, and then stirred in an ice-water bath for 15 minutes; then trifluoromethanesulfonic acid dissolved in dichloromethane was added dropwise to the reaction system, and stirred for 4 hours, wherein the molar ratio of the 2,2'-bipyridine-5,5'-dicarboxaldehyde to the trifluoromethanesulfonic acid was 0.47:1.2; after the reaction was completed, a light yellow solid was obtained by filtration, and then recrystallized in acetonitrile and ether to obtain 2H + -BPDA (white solid);

[0093] The 2H + -BPDA and dibenzo-2,4-crown-8 were added to ethanol and stirred at room temperature for 24 hours, then the solvent was removed by rotary evaporation and dried to obtain the pyridine crown ether ring compound (yellow solid);

[0094] An aminosilane coupling agent (specifically N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane) and zinc powder are added to anhydrous ethanol, stirred at 55°C for 1.5 hours, and then the pyridine crown ether ring compound is added and continued to be stirred at 55°C for 1.5 hours, filtered, washed and dried to obtain the modified zinc powder; wherein the weight ratio of the pyridine crown ether ring compound, the aminosilane coupling agent, the zinc powder and the anhydrous ethanol is 1:0.5:2.2:10.

[0095] The preparation method of the above inorganic zinc-rich coating is the same as that of Example 1.

[0096] Example 3

[0097] This example provides an inorganic zinc-rich coating, wherein the inorganic zinc-rich coating comprises component A and component B in a weight ratio of 1:2.3;

[0098] In parts by weight, the component A comprises the following raw materials: 85 parts of silicate solution and 2 parts of auxiliary agent;

[0099] In parts by weight, the B component includes the following raw materials: 20 parts of modified zinc powder and 25 parts of zinc powder;

[0100] The modified zinc powder is obtained by composite-modifying zinc powder with pyridine crown ether ring compounds and aminosilane coupling agents;

[0101] The silicate solution is obtained by compounding a lithium silicate solution and a potassium silicate solution in a weight ratio of 1:8; the modulus of the lithium silicate is 4.8, and the modulus of the potassium silicate is 6.5; in terms of weight percentage, the solid content of the lithium silicate solution is 24%; in terms of weight percentage, the solid content of the potassium silicate solution is 25%;

[0102] The auxiliary agent is composed of a thickener and a defoamer in a weight ratio of 5:1;

[0103] The particle size of the zinc powder is 800 mesh;

[0104] The preparation method of the modified zinc powder comprises the following process:

[0105] 2,2'-bipyridine-5,5'-dicarboxaldehyde was dissolved in dichloromethane solvent, and then stirred in an ice-water bath for 15 minutes; then trifluoromethanesulfonic acid dissolved in dichloromethane was added dropwise to the reaction system, and stirred for 4 hours, wherein the molar ratio of the 2,2'-bipyridine-5,5'-dicarboxaldehyde to the trifluoromethanesulfonic acid was 0.47:1.2; after the reaction was completed, a light yellow solid was obtained by filtration, and then recrystallized in acetonitrile and ether to obtain 2H + -BPDA (white solid);

[0106] The 2H + -BPDA and dibenzo-2,4-crown-8 were added to ethanol and stirred at room temperature for 24 hours, then the solvent was removed by rotary evaporation and dried to obtain the pyridine crown ether ring compound (yellow solid);

[0107] An aminosilane coupling agent (specifically N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane) and zinc powder are added to anhydrous ethanol, stirred at 55°C for 1.5 hours, and then the pyridine crown ether ring compound is added and continued to be stirred at 55°C for 1.5 hours, filtered, washed and dried to obtain the modified zinc powder; wherein the weight ratio of the pyridine crown ether ring compound, the aminosilane coupling agent, the zinc powder and the anhydrous ethanol is 1.5:1:3:20.

[0108] The preparation method of the above inorganic zinc-rich coating is the same as that of Example 1.

[0109] Comparative Example 1

[0110] This example provides an inorganic zinc-rich coating and a preparation method thereof, which is different from Example 1 only in that the modulus of the lithium silicate is 8.0, and the modulus of the potassium silicate is 2.8; the remaining steps and parameters are the same.

[0111] Comparative Example 2

[0112] This example provides an inorganic zinc-rich coating and a preparation method thereof, which differs from Example 1 only in that: the modified zinc powder is obtained by compositely modifying zinc powder using a crown ether ring compound and an aminosilane coupling agent, and specifically includes the following process: adding an aminosilane coupling agent (specifically N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane) and zinc powder to anhydrous ethanol, stirring at 55° C. for 1.5 hours, then adding the dibenzo-24-crown ether-8 and continuing to stir at 55° C. for 1.5 hours, filtering, washing and drying to obtain the modified zinc powder; wherein the weight ratio of the dibenzo-24-crown ether-8, the aminosilane coupling agent, the zinc powder and the anhydrous ethanol is 1.2:0.8:2.5:15; and the remaining steps and parameters are the same.

[0113] Test Case

[0114] In this example, the inorganic zinc-rich coatings obtained in the above Examples 1 to 3 and Comparative Examples 1 to 2 were subjected to performance tests according to existing test methods and standards. The test results are shown in Table 1.

[0115] Table 1

[0116]

[0117] It can be seen from Table 1 that, compared with the comparative example, the inorganic zinc-rich coating provided by the embodiment of the present invention has better anti-slip performance and higher adhesion, and the effect of embodiment 1 is the best. In addition, the inorganic zinc-rich coating obtained by the embodiment of the present invention is subjected to a salt spray resistance test, and the test results show that the resistance is ≥1000h, which meets the anti-corrosion index requirements.

[0118] In summary, the embodiments of the present invention provide an inorganic zinc-rich coating and its preparation method and application. By using a silicate solution with a suitable modulus as a base material, introducing specific modified zinc powder and zinc powder as anti-corrosion components, and supplementing with additives to improve construction performance and film-forming performance, the comprehensive performance of the inorganic zinc-rich coating, such as anti-slip performance and adhesion, is significantly improved. It is particularly suitable for high-strength bolt connection surface treatment of steel components such as bridges and prefabricated buildings. Its excellent performance can effectively protect the connection surface from corrosion and wear, and provide long-lasting and stable protection for high-strength bolts, thereby improving the service life and safety of the connection surface.

[0119] Various embodiments of the present invention may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present invention; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0120] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. An inorganic zinc-rich coating, It is characterized in that The inorganic zinc-rich coating comprises component A and component B; In parts by weight, the component A comprises the following raw materials: 75-85 parts of silicate solution and 0.5-2 parts of auxiliary agent; In parts by weight, the B component includes the following raw materials: 10 to 20 parts of modified zinc powder and 25 to 35 parts of zinc powder; The modified zinc powder is obtained by composite-modifying zinc powder with pyridine crown ether ring compounds and aminosilane coupling agents; The silicate solution is obtained by compounding a lithium silicate solution and a potassium silicate solution. The modulus of the lithium silicate is 3-5, and the modulus of the potassium silicate is 5-6.

5.

2. The inorganic zinc-rich coating according to claim 1, It is characterized in that The weight ratio of the A component to the B component is 1:(1.8-2.3).

3. The inorganic zinc-rich coating according to claim 1, It is characterized in that In parts by weight, the A component includes the following raw materials: 80 parts of silicate solution and 1.5 parts of additives; In parts by weight, the B component includes the following raw materials: 15 parts of modified zinc powder and 30 parts of zinc powder.

4. The inorganic zinc-rich coating according to claim 1, It is characterized in that The weight ratio of the lithium silicate solution to the potassium silicate solution is (1-2):(5-8); in terms of weight percentage, the solid content of the lithium silicate solution is 19-24%; in terms of weight percentage, the solid content of the potassium silicate solution is 24-26%.

5. The inorganic zinc-rich coating according to claim 1, It is characterized in that Preparation method of modified zinc powder The process includes: 2,2'-Bipyridine-5,5'-dicarboxaldehyde was first stirred with trifluoromethanesulfonic acid, then filtered and recrystallized to obtain 2H + -BPDA; The 2H + -BPDA and dibenzo-24-crown-8 are stirred for a second time, and then the solvent is removed to obtain the pyridine crown ether ring compound; Adding the aminosilane coupling agent and zinc powder into anhydrous ethanol for a third stirring, then adding the pyridine crown ether ring compound for a fourth stirring, filtering, washing and drying to obtain the modified zinc powder; The molar ratio of the 2,2'-bipyridine-5,5'-dicarboxaldehyde to the trifluoromethanesulfonic acid is (0.45-0.50): (1.1-1.3); the 2H + -BPDA and the dibenzo-24-crown ether-8 have a molar ratio of 1:1; the weight ratio of the pyridine crown ether ring compound, the aminosilane coupling agent, the zinc powder and the anhydrous ethanol is (1-1.5):(0.5-1):(2.2-3):(10-20).

6. The inorganic zinc-rich coating according to claim 5, It is characterized in that The working condition parameters of the first stirring include: temperature of 0 to 5°C, stirring time of 3.5 to 5 hours; the working condition parameters of the second stirring include: temperature of room temperature, stirring time of 20 to 30 hours; the working condition parameters of the third stirring include: temperature of 50 to 60°C, stirring time of 1 to 2 hours; the working condition parameters of the fourth stirring include: temperature of 50 to 60°C, stirring time of 1 to 2 hours; the aminosilane coupling agent includes at least one of N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane and 3-aminopropyltrimethoxysilane.

7. The inorganic zinc-rich coating according to claim 1, It is characterized in that The auxiliary agent is composed of a thickener and a defoamer in a weight ratio of (3-5):1; the particle size of the zinc powder is 500-800 meshes.

8. A method for preparing the inorganic zinc-rich coating according to any one of claims 1 to 7, It is characterized in that The preparation method comprises the following steps: Stirring and mixing the raw materials in component A to obtain component A; The raw materials in component B are added to component A and stirred to obtain the inorganic zinc-rich coating.

9. Use of the inorganic zinc-rich coating according to any one of claims 1 to 8 in treating bolt connection surfaces.

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