Moisture-resistant, rust-resistant and anticorrosive coating and preparation method thereof

Abstract

The invention relates to the technical field of anticorrosive coatings, and discloses a moisture-resistant, rust-resistant and anticorrosive coating and a preparation method thereof.The coating comprises a main agent and a curing agent which are ready to use after being mixed, and the mass ratio of the main agent to the curing agent is (3-6): 1; the main agent comprises the following components in parts by mass: 100 parts of an epoxy resin mixture, 10-50 parts of an active auxiliary agent, 5-50 parts of mica iron oxide, 10-30 parts of titanium dioxide, 1-20 parts of strontium carbonate and 10-40 parts of aluminum triphosphate; the curing agent comprises 100 parts of benzyl alcohol, 50-100 parts of amine curing agent and 1-20 parts of salicylic acid. The moisture-proof, rust-proof and anticorrosive coating prepared by the invention has the characteristics of quick drying and no volatile organic compounds, and the formed coating has higher toughness and hardness compared with a common epoxy resin coating, so that the robustness of the coating is enhanced, and the service life of the coating is prolonged; when the paint is used, only floating rust, oxide skin and the like on the surface of a steel substrate need to be removed, the paint can be directly coated on the surface of a metal surface which cannot be subjected to thorough rust removal or slight rust removal, and the obtained coating has excellent protection performance.

Description

Technical Field

[0001] The present invention relates to the technical field of anti-corrosion coatings, and in particular to a moisture-resistant and rust-resistant anti-corrosion coating and a preparation method thereof. Background Art

[0002] Corrosion of metal structures is not only a technical challenge but also an economic burden. Statistics show that economic losses from metal corrosion account for 3%-5% of China's gross national product (GNP), costing China over 3.5 trillion yuan annually. This staggering figure highlights the importance of metal corrosion prevention. Among the many protective methods, coatings are one of the most common and effective. By forming an anti-corrosion coating on the metal surface, they can significantly extend the service life of metal structures and reduce maintenance costs.

[0003] Anti-corrosion coatings, as a key measure for metal protection, face many challenges in practical applications. The traditional coatings that are widely used currently have extremely high requirements for substrate surface pretreatment. It is necessary to ensure that the metal surface is free of rust, oil, and remains dry and flat to ensure the effectiveness and durability of the coating. However, for specific facilities such as signal towers and mountain bridges, their construction environment is often complex and changeable: high-altitude operations increase safety risks, and the field environment lacks complete supporting facilities, making it extremely difficult to meet the surface pretreatment standards required for commonly used coatings. In this case, even with the use of high-quality coatings, it is difficult to form an anti-corrosion coating with sufficient protective capabilities on the surface of the rusted substrate, thereby weakening the overall protective effect. Therefore, there is an urgent need to develop a new type of anti-corrosion coating with excellent moisture and rust resistance. Faced with the above dilemma, the development of a new type of anti-corrosion coating is particularly urgent. The ideal new anti-corrosion coating should have the following characteristics: 1. Excellent moisture and rust resistance: It can work stably for a long time in a humid environment, effectively prevent moisture and oxygen from penetrating into the metal surface, and delay or even prevent the occurrence of corrosion reactions.

[0004] 2. Low surface pretreatment requirements: It can be directly applied on metal surfaces that are slightly rusted or have not been strictly pretreated, simplifying the construction process and reducing manpower and material costs.

[0005] 3. Ability to adapt to complex environments: Suitable for construction under various harsh conditions such as high altitude and outdoor conditions, ensuring that the coating quality is not affected by environmental factors.

[0006] 4. Long-term protection: One-time construction can provide long-term reliable protection, reducing the frequency and cost of subsequent maintenance. Summary of the Invention

[0007] The present invention aims to provide a moisture-resistant and rust-resistant anti-corrosion coating and a preparation method thereof, so as to solve the problem that the existing anti-corrosion coatings have insufficient adhesion and protection on the surface of low-surface-treated substrates; even when the metal surface is wet and rusty, only minimal surface treatment is required for direct coating to form a coating with excellent protective performance.

[0008] To achieve the above-mentioned object, the present invention adopts the following technical scheme: a moisture-resistant, rust-resistant and anti-corrosion coating, comprising a ready-to-mix main agent and a curing agent, wherein the mass ratio of the main agent to the curing agent is 3-6:1; in parts by mass, the main agent comprises 100 parts of an epoxy resin mixture, 10-50 parts of an active auxiliary agent, 5-50 parts of micaceous iron oxide, 10-30 parts of titanium dioxide, 1-20 parts of strontium carbonate and 10-40 parts of aluminum tripolyphosphate; the curing agent comprises 100 parts of benzyl alcohol, 50-100 parts of an amine curing agent and 1-20 parts of salicylic acid.

[0009] The principle and advantages of this solution are as follows: in actual application, in this technical solution, in response to the problems existing in the prior art anti-corrosion coating, the inventors have comprehensively optimized the formula and preparation process of the anti-corrosion coating. In terms of the formula composition: the epoxy resin mixture is the resin matrix in the coating, reacts with the curing agent to form a coating film, and plays a role in adjusting the properties of the prepared coating film; mica iron oxide has good chemical stability and strong reflectivity to visible-ultraviolet light, which can slow down the aging of the paint film; titanium dioxide has good chemical stability, strong adhesion, strong hiding power, and high dielectric constant, which can slow down electrochemical corrosion and enhance the adhesion of the coating; aluminum tripolyphosphate has good thermal stability, and the tripolyphosphate ion has a strong chelating ability with various metal ions, forming an inorganic network passivation film with strontium carbonate, thereby improving the film-forming and rust-resistant properties of the coating. On the other hand, this technical solution optimizes the addition ratio of the raw materials in the formula. When the content of mica iron oxide in the main agent is less than the above range, there is a problem of poor rust resistance of the coating. When the content of mica iron oxide in the main agent exceeds the above range, the dispersibility and storage stability of the coating will deteriorate. When the content of titanium dioxide in the main agent is less than the above range, it will affect the rust resistance and adhesion of the coating. When the content of titanium dioxide in the main agent exceeds the above range, the coating will have poor sag. When the content of strontium carbonate in the main agent is less than the above range, there is a problem of poor rust resistance of the coating. When the content of strontium carbonate in the main agent exceeds the above range, the coating will have poor sag and storage properties. When the content of aluminum tripolyphosphate in the main agent is less than the above range, the rust resistance of the coating will deteriorate. When the content of aluminum tripolyphosphate in the main agent exceeds the above range, the coating will have poor storage properties and film cracking problems. When the content of amine curing agent in the curing agent is less than the above range, the coating will have delayed curing and drying. When the content of amine curing agent in the curing agent exceeds the above range, curing will be faster, the coating will have poor film adhesion, and the strength will deteriorate. This solution can ensure that the anti-corrosion coating can take into account rust resistance, sag, adhesion, dispersibility, film crack resistance and stability through systematic optimization of each synergistic component. In addition, this technical solution also explores the ratio of the main agent and the curing agent. Studies have shown that when the mixing ratio of the curing agent part and the main agent part is less than the above range, the physical properties of the coating such as long-term rust resistance and water resistance will be reduced. When the mixing ratio of the curing agent part and the main agent part exceeds the above range, the moisture resistance and rust resistance of the coating will deteriorate.

[0010] In summary, the beneficial effects of this technical solution are: 1. The strontium salt in the main agent of this technical solution forms a salt bridge through the synergistic effect with aluminum tripolyphosphate, so that the tripolyphosphate ions form a cross-linked network structure, which exhibits more stable properties when playing the role of rust converter, and at the same time greatly limits the tendency of tripolyphosphate ions to hydrolyze.

[0011] 2. Compared with traditional coatings, the moisture-resistant and rust-resistant anti-corrosion coating prepared by this technical solution can still provide strong adhesion and corrosion resistance after being applied to the surface of a wet and rusty substrate, and can achieve long-lasting protection. The coating is also characterized by fast drying and no volatile organic compounds (VOCs). The resulting coating has higher toughness, hardness, and impact resistance than common epoxy resin coatings, which helps to enhance the robustness and lifespan of the coating. In addition, when using it, only loose rust, scale, and other substances on the surface of the steel substrate need to be removed. For metal surfaces that cannot be completely rusted or have only slight rust removal, the rust-resistant paint can be applied directly on the surface, and the resulting coating has excellent protective properties.

[0012] Preferably, as an improvement, the epoxy resin mixture is obtained by mixing bisphenol A resin and bisphenol F resin in a mass ratio of 1 to 3:1.

[0013] In this technical solution, the epoxy resin mixture can improve the anti-crystallization ability of the above-mentioned coating at room temperature and the toughness of the formed coating film. This technical solution creatively uses bisphenol F resin and compounds it with bisphenol A resin to obtain an epoxy resin mixture. The type of resin in the epoxy resin mixture and the addition ratio have a key impact on the performance of the epoxy resin. When the weight ratio is less than the above range, that is, when a smaller amount of bisphenol F epoxy resin is included based on bisphenol A epoxy resin, as the toughness and ductility decrease, the coating film has problems of reduced adhesion and reduced impact resistance; when the weight ratio is greater than the above range, that is, when a larger amount of bisphenol F epoxy resin is included based on bisphenol A epoxy resin, the coating film has problems of reduced tensile strength and reduced hardness.

[0014] Preferably, as an improvement, the epoxy equivalent weight of the bisphenol A epoxy resin is 170-200 g / eq; and the epoxy equivalent weight of the bisphenol F epoxy resin is 150-210 g / eq.

[0015] In this technical solution, limiting the epoxy equivalent weight (EEW) of the epoxy resin ensures the storage stability of the epoxy resin mixture. When the EEW of the bisphenol A epoxy resin exceeds the above range, the toughness of the epoxy resin mixture is difficult to maintain, and the resulting coating's resistance to substrate surfaces is reduced. When the EEW of the bisphenol F epoxy resin exceeds the above range, the viscosity of the epoxy resin mixture increases, reducing the mechanical properties and rust prevention capabilities of the coating film.

[0016] Preferably, as an improvement, the active agent is dodecyl and tetradecyl glycidyl ether (AGE), and the addition amount of dodecyl and tetradecyl glycidyl ether is 10-50% of the mass of the epoxy resin mixture; the epoxy equivalent weight of AGE is 270-350 g / eq.

[0017] In this technical solution, the active agent acts as a solvent to dilute the epoxy resin, enhancing its dispersibility while also reacting with the curing agent to form a coating film. This minimizes the increase in volatile organic compound (VOC) content, contributing to safer and more environmentally friendly use. Furthermore, research has shown that when the amount of dodecyl and tetradecyl glycidyl ether (AGE) added to the base agent is too low, the coating's flowability deteriorates. When the AGE content exceeds the above range, the coating's storage stability deteriorates.

[0018] Preferably, as an improvement, the average diameter of mica iron oxide is 20-80 μm; the average particle size of titanium dioxide is 2-20 μm; the average particle size of strontium carbonate is 2-50 μm; and the average particle size of aluminum tripolyphosphate is 2-50 μm.

[0019] In the present technical solution, when the average particle size of mica iron oxide is smaller than the above range, there are problems with reduced rust resistance and durability; when the average particle size of mica iron oxide is larger than the above range, there are problems with reduced dispersibility and poor storage of the coating. When the average particle size of titanium dioxide is smaller than the above range, the rust resistance of the coating film will deteriorate; when the average particle size of titanium dioxide is larger than the above range, there are problems with reduced adhesion of the coating film and reduced dispersibility of the coating; when the average particle size of strontium carbonate is smaller than the above range, the rust resistance of the coating film will deteriorate; when the average particle size of strontium carbonate is larger than the above range, the dispersibility of the coating will be reduced and the coating film will be uneven; when the average particle size of aluminum tripolyphosphate is smaller than the above range, the rust resistance of the coating film will deteriorate; when the average particle size of aluminum tripolyphosphate is larger than the above range, the dispersibility of the coating will be reduced and the coating film will be easily broken.

[0020] Preferably, as an improvement, the main agent further comprises one or more of a dispersant, a defoamer, a thickener, a silane compound and an anti-rust pigment.

[0021] In this technical solution, the above-mentioned auxiliary agents can be added to the main agent in appropriate amounts to impart specific properties to the coating.

[0022] Preferably, as an improvement, the amine curing agent is obtained by mixing aliphatic primary amine and aromatic primary amine in a mass ratio of 1:1-2.

[0023] In the present technical solution, if the weight ratio of the aliphatic primary amine to the aromatic primary amine is not properly controlled, the curing and drying of the coating film will be delayed, and the strength of the coating film will deteriorate after complete curing.

[0024] Preferably, as an improvement, the aliphatic primary amines may include, for example, propylene diamine, ethylene diamine, 2-(aminomethyl)propane-1,3-diamine, 5-amino-1,3,3-trimethylcyclohexanemethylamine, etc.; the aromatic primary amines may include, for example, phenylenediamine, p-phenylenediamine, 1-benzofuran-2-amine, etc.

[0025] Preferably, as an improvement, the curing agent further comprises one or more of a thickener and a preservative.

[0026] Preferably, as an improvement, a method for preparing a moisture-resistant, rust-resistant, and anti-corrosion coating comprises the following steps: Step 1, preparation of the main agent: 100 parts of the epoxy resin mixture, 10-50 parts of the active agent, 5-50 parts of micaceous iron oxide, 10-30 parts of titanium dioxide, 1-20 parts of strontium carbonate and 10-40 parts of aluminum tripolyphosphate are mixed to obtain the main agent; Step 2: Preparation of a curing agent: Mix 100 parts of benzyl alcohol, 50-100 parts of an amine curing agent, and 1-20 parts of salicylic acid to obtain a curing agent; Step 3: Store the main agent and curing agent separately and use them immediately after mixing. The mixing ratio of the main agent to the curing agent is 3~6:1. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a diagram of the hardness test results in an embodiment of the present invention.

[0028] Figure 2 This is a graph showing the impact performance test results in an embodiment of the present invention.

[0029] Figure 3 This is a sample diagram before flexibility testing in an embodiment of the present invention.

[0030] Figure 4 This is a sample diagram after flexibility testing in an embodiment of the present invention.

[0031] Figure 5 This is the original state picture of the test sample before painting.

[0032] Figure 6 This is the state picture of the test sample after painting.

[0033] Figure 7 This is the state diagram after the pull-open method test.

[0034] Figure 8 This is the status diagram after 3000h neutral salt spray test.

[0035] Figure 9 The following are the storage stability test results of the embodiments of the present invention.

[0036] Figure 10 2 is a scanning electron microscope image of the main agent in the embodiment of the present invention.

[0037] Figure 11 2 is a scanning electron microscope image of the main agent in the embodiment of the present invention.

[0038] Figure 12 2 is a scanning electron microscope image of the main agent in the embodiment of the present invention.

[0039] Figure 13 It is the infrared spectrum of the main agent in the embodiment of the present invention. DETAILED DESCRIPTION

[0040] The following is further described in detail through specific embodiments, but the embodiments of the present invention are not limited thereto. Unless otherwise specified, the technical means used in the following embodiments are conventional means well known to those skilled in the art; the experimental methods used are all conventional methods; and the materials, reagents, etc. used are all commercially available.

[0041] Program Overview: A moisture-resistant, rust-resistant and anti-corrosion coating comprises a ready-to-mix main agent and a curing agent, wherein the mass ratio of the main agent to the curing agent is 3-6:1. In parts by mass, the main agent comprises 100 parts of an epoxy resin mixture, 10-50 parts of an active auxiliary agent, 5-50 parts of micaceous iron oxide, 10-30 parts of titanium dioxide, 1-20 parts of strontium carbonate and 10-40 parts of aluminum tripolyphosphate; and the curing agent comprises 100 parts of benzyl alcohol, 50-100 parts of an amine curing agent and 1-20 parts of salicylic acid.

[0042] The epoxy resin mixture is obtained by mixing bisphenol A resin and bisphenol F resin in a mass ratio of 1 to 3:1; the epoxy equivalent weight (EEW) of the bisphenol A epoxy resin is 170 to 200 g / eq; and the epoxy equivalent weight (EEW) of the bisphenol F epoxy resin is 150 to 210 g / eq.

[0043] The active additives are dodecyl and tetradecyl glycidyl ether (AGE), and the addition amount of dodecyl and tetradecyl glycidyl ether is 10-50% of the mass of the epoxy resin mixture; the epoxy equivalent weight (EEW) of AGE is 270-350 g / eq.

[0044] Mica iron oxide is in the form of flakes with an average diameter of 20-80 μm.

[0045] Titanium dioxide is in powder form with an average particle size of 2-20 μm.

[0046] Strontium carbonate is in the form of powder with an average particle size of 2-50 μm.

[0047] Aluminum tripolyphosphate is in the form of powder with an average particle size of 2-50 μm.

[0048] In addition, appropriate amounts of dispersants, defoamers, thickeners, silane compounds and anti-rust pigments can be added to the main agent.

[0049] The amine curing agent is obtained by mixing aliphatic primary amine and aromatic primary amine in a mass ratio of 1:1-2; the aliphatic primary amine is at least one of propylene diamine, ethylene diamine, 2-(aminomethyl)propane-1,3-diamine, and 5-amino-1,3,3-trimethylcyclohexanemethylamine; and the aromatic primary amine is at least one of phenylenediamine, p-phenylenediamine, and 1-benzofuran-2-amine.

[0050] In addition, appropriate amounts of thickeners and preservatives may be added to the curing agent.

[0051] A method for preparing a moisture-resistant, rust-resistant, and anti-corrosion coating comprises the following steps: Step 1, preparation of the main agent: 100 parts of the epoxy resin mixture, 10-50 parts of the active agent, 5-50 parts of micaceous iron oxide, 10-30 parts of titanium dioxide, 1-20 parts of strontium carbonate and 10-40 parts of aluminum tripolyphosphate are mixed to obtain the main agent; Specifically, bisphenol A epoxy resin, bisphenol F epoxy resin, active agent and optional liquid additives such as dispersant, defoamer, thickener, silane compound are first added to a container in proportion, and stirred and dispersed at 1500 r / min for 20 minutes to fully mix; then, micaceous iron oxide, titanium dioxide and strontium carbonate are added in proportion, and stirred and dispersed at 3000 r / min for 30 minutes to fully disperse the added solids in the liquid; then, aluminum tripolyphosphate is added in proportion, and stirred and dispersed at 1500 r / min for 10 minutes, and then stirred and dispersed at 3000 r / min for 2 hours, during which the temperature in the container must be controlled below 80° C.; finally, the prepared coating main agent is allowed to cool to below 50° C. and then sealed for storage; Step 2: Preparation of a curing agent: Mix 100 parts of benzyl alcohol, 50-100 parts of an amine curing agent, and 1-20 parts of salicylic acid to obtain a curing agent; Step 3: Store the main agent and curing agent separately and use them immediately after mixing. The mixing ratio of the main agent to the curing agent is 3~6:1.

[0052] Example 1 A moisture-resistant, rust-resistant and anti-corrosion coating comprises a ready-to-mix main agent and a curing agent, wherein the mass ratio of the main agent to the curing agent is 3:1; in parts by mass, the main agent comprises 100 parts of an epoxy resin mixture, 10 parts of an active auxiliary agent, 50 parts of micaceous iron oxide, 10 parts of titanium dioxide, 20 parts of strontium carbonate and 10 parts of aluminum tripolyphosphate; the curing agent comprises 100 parts of benzyl alcohol, 50 parts of an amine curing agent and 1 part of salicylic acid.

[0053] The epoxy resin mixture is obtained by mixing bisphenol A resin and bisphenol F resin in a mass ratio of 1:1; the epoxy equivalent weight (EEW) of the bisphenol A epoxy resin is 170-200 g / eq; and the epoxy equivalent weight (EEW) of the bisphenol F epoxy resin is 150-210 g / eq.

[0054] The active additives are dodecyl and tetradecyl glycidyl ether (AGE), and the addition amount of dodecyl and tetradecyl glycidyl ether is 10% of the mass of the epoxy resin mixture; the epoxy equivalent weight (EEW) of AGE is 270-350 g / eq.

[0055] Mica iron oxide is in the form of flakes with an average diameter of 20-80 μm.

[0056] Titanium dioxide is in powder form with an average particle size of 2-20 μm.

[0057] Strontium carbonate is in the form of powder with an average particle size of 2-50 μm.

[0058] Aluminum tripolyphosphate is in the form of powder with an average particle size of 2-50 μm.

[0059] In addition, appropriate amounts of dispersants, defoamers, thickeners, silane compounds and anti-rust pigments can be added to the main agent.

[0060] The amine curing agent is obtained by mixing aliphatic primary amine and aromatic primary amine in a mass ratio of 1:1; the aliphatic primary amine is propylene diamine; and the aromatic primary amine is phenylenediamine.

[0061] In addition, appropriate amounts of thickeners and preservatives may be added to the curing agent.

[0062] A method for preparing a moisture-resistant, rust-resistant, and anti-corrosion coating comprises the following steps: Step 1, preparation of the main agent: 100 parts of the epoxy resin mixture, 10 parts of the active agent, 50 parts of micaceous iron oxide, 10 parts of titanium dioxide, 20 parts of strontium carbonate and 10 parts of aluminum tripolyphosphate are mixed to obtain the main agent; Specifically, bisphenol A epoxy resin, bisphenol F epoxy resin, active agent and optional liquid additives such as dispersant, defoamer, thickener, silane compound are first added to a container in proportion, and stirred and dispersed at 1500 r / min for 20 minutes to fully mix; then, micaceous iron oxide, titanium dioxide and strontium carbonate are added in proportion, and stirred and dispersed at 3000 r / min for 30 minutes to fully disperse the added solids in the liquid; then, aluminum tripolyphosphate is added in proportion, and stirred and dispersed at 1500 r / min for 10 minutes, and then stirred and dispersed at 3000 r / min for 2 hours, during which the temperature in the container must be controlled below 80° C.; finally, the prepared coating main agent is allowed to cool to below 50° C. and then sealed for storage; Step 2, preparation of a curing agent: mixing 100 parts of benzyl alcohol, 50 parts of an amine curing agent, and 1 part of salicylic acid to obtain a curing agent; Step 3: Store the main agent and curing agent separately and use them immediately after mixing. The mixing ratio of the main agent to the curing agent is 3:1.

[0063] Example 2 A moisture-resistant, rust-resistant and anti-corrosion coating comprises a ready-to-mix main agent and a curing agent, wherein the mass ratio of the main agent to the curing agent is 6:1; in parts by mass, the main agent comprises 100 parts of an epoxy resin mixture, 50 parts of an active additive, 5 parts of micaceous iron oxide, 30 parts of titanium dioxide, 1 part of strontium carbonate and 40 parts of aluminum tripolyphosphate; the curing agent comprises 100 parts of benzyl alcohol, 100 parts of an amine curing agent and 20 parts of salicylic acid.

[0064] The epoxy resin mixture is obtained by mixing bisphenol A resin and bisphenol F resin in a mass ratio of 3:1; the epoxy equivalent weight (EEW) of the bisphenol A epoxy resin is 170-200 g / eq; and the epoxy equivalent weight (EEW) of the bisphenol F epoxy resin is 150-210 g / eq.

[0065] The active additives are dodecyl and tetradecyl glycidyl ether (AGE), and the addition amount of dodecyl and tetradecyl glycidyl ether is 10-50% of the mass of the epoxy resin mixture; the epoxy equivalent weight (EEW) of AGE is 270-350 g / eq.

[0066] Mica iron oxide is in the form of flakes with an average diameter of 20-80 μm.

[0067] Titanium dioxide is in powder form with an average particle size of 2-20 μm.

[0068] Strontium carbonate is in the form of powder with an average particle size of 2-50 μm.

[0069] Aluminum tripolyphosphate is in the form of powder with an average particle size of 2-50 μm.

[0070] In addition, appropriate amounts of dispersants, defoamers, thickeners, silane compounds and anti-rust pigments can be added to the main agent.

[0071] The amine curing agent is obtained by mixing aliphatic primary amine and aromatic primary amine in a mass ratio of 1:2; the aliphatic primary amine is obtained by mixing 2-(aminomethyl)propane-1,3-diamine and 5-amino-1,3,3-trimethylcyclohexanemethylamine in a mass ratio of 1:1; and the aromatic primary amine is 1-benzofuran-2-amine.

[0072] In addition, appropriate amounts of thickeners and preservatives may be added to the curing agent.

[0073] A method for preparing a moisture-resistant, rust-resistant, and anti-corrosion coating comprises the following steps: Step 1, preparation of the main agent: 100 parts of the epoxy resin mixture, 50 parts of the active agent, 5 parts of micaceous iron oxide, 30 parts of titanium dioxide, 1 part of strontium carbonate and 40 parts of aluminum tripolyphosphate are mixed to obtain the main agent; Specifically, bisphenol A epoxy resin, bisphenol F epoxy resin, active agent and optional liquid additives such as dispersant, defoamer, thickener, silane compound are first added to a container in proportion, and stirred and dispersed at 1500 r / min for 20 minutes to fully mix; then, micaceous iron oxide, titanium dioxide and strontium carbonate are added in proportion, and stirred and dispersed at 3000 r / min for 30 minutes to fully disperse the added solids in the liquid; then, aluminum tripolyphosphate is added in proportion, and stirred and dispersed at 1500 r / min for 10 minutes, and then stirred and dispersed at 3000 r / min for 2 hours, during which the temperature in the container must be controlled below 80° C.; finally, the prepared coating main agent is allowed to cool to below 50° C. and then sealed for storage; Step 2, preparation of a curing agent: mixing 100 parts of benzyl alcohol, 100 parts of an amine curing agent, and 20 parts of salicylic acid to obtain a curing agent; Step 3: Store the main agent and curing agent separately and use them immediately after mixing. The mixing ratio of the main agent to the curing agent is 6:1.

[0074] Experimental Example 1 Performance Characterization Test method: The moisture-resistant, rust-resistant, and anti-corrosion coating prepared in Example 1 was applied to a 0.2-0.3 mm thick tinplate substrate, and then a performance test was performed. The test method and results are as follows: 1. Hardness: Test method GB / T 6739-2022 The load is 7.35±0.15 N and the test pencil is a Mitsubishi pencil.

[0075] The test results are as follows Figure 1 As shown, the results show that the pencil hardness of the coating of the present invention is 2H.

[0076] 2. Impact resistance: Test method: Drop hammer impact test (height: 1000mm; including both front and back sides) The test results are as follows Figure 2 As shown, the results show that the coating of the present invention has good impact resistance.

[0077] 3. Paint film flexibility: Test method GB / T 1731-2020 Section 4 The coating thickness is 65.7μm and the substrate thickness is 0.49mm The test results are as follows Figure 3-4 As shown, the smallest undamaged shaft rod is Φ3 mm, and the structure shows that the coating of the present invention has good anti-bending ability.

[0078] The results of the above tests show that the coating of the present invention has good flexibility and hardness.

[0079] 4. Adhesion: Test method: GB / T 5210-2006 Section 9.4.2 Paint film adhesion (pull-off method). Sample preparation: The surface of the test sample is sandblasted and then corroded with salt water. The surface is covered with rust. The grade is similar to Grade C in ISO8501-1:2007. Figure 5 As shown. Prior to coating application, the surface was rinsed with fresh water.

[0080] The state of the paint after coating is as follows Figure 6 The test results are shown in Table 1 and Figure 7 As shown, the results indicate that the present invention is tolerant to low surface finish steel substrates such as wet and rusty surfaces and provides good adhesion when applied thereon.

[0081] Table 1 Adhesion strength of coating on wet and rusty surface

[0082] Note: In Table 1, A: cohesive failure of substrate; A / B: adhesion failure between the first coating and substrate; B: cohesive failure of the first coating; B / C: adhesion failure between the first coating and the second coating; – / Y: adhesion failure between the last coating and the adhesive; Y: cohesive failure of the adhesive; Y / Z: bonding failure between the adhesive and the test column.

[0083] 5. Corrosion resistance test: Test method reference: GB / T 10125-2021 neutral salt spray test The test results are as follows Figure 8 As shown, the results show that after 3000 hours of neutral salt spray test, there are no new defects or rust on the coating surfaces of Class A (dry rusty surface) and Class B (wet rusty surface) samples. The coating prepared by the present invention has strong corrosion resistance.

[0084] 6. Storage stability: Test method reference: Evaluation items and methods in GB / T 6753.3 Test method for storage stability of coatings.

[0085] The results are as follows Figure 9 As shown, as of now, after 6 months of storage under natural environment conditions, the paint has not shown any skinning, pressure, corrosion or odor; it is completely suspended without sedimentation; the viscosity change is less than 5%, which can be considered to be within the self-test error range; with regard to the particles, glue blocks and brush marks of the paint film, the paint film produced after storage is basically the same as the paint film produced by the new paint.

[0086] Experimental Example 2: Morphology Detection The main agent prepared in Example 1 of the present invention was observed by scanning electron microscope (500-1500 times), and the results were as follows: Figure 10-12As shown in the image, the components are evenly dispersed, and the solid particles and mica iron oxide flakes are clearly visible. Good dispersion is important for the adhesion, mechanical properties, and corrosion resistance of the coating.

[0087] Experimental Example 3 Infrared Spectrum Detection The main agent prepared in Example 1 of the present invention was subjected to infrared spectroscopy. The results are as follows Figure 13 As shown in the figure, the characteristic peaks indicate that the coating base prepared in this embodiment of the present invention contains functional groups such as alkyl groups, benzene ring structures, ether bonds, and ester bonds. The benzene ring structure imparts a certain degree of chemical stability to the coating, being relatively stable and not easily destroyed by common chemical reagents. The alkyl structure also provides a certain degree of chemical inertness, making the coating more resistant to certain acidic and alkaline environments.

[0088] The above is only an embodiment of the present invention, and the common knowledge such as the specific technical solutions and / or characteristics in the solution are not described in detail here. It should be pointed out that for those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the description can be used to interpret the content of the claims.

Claims

1. A moisture-resistant, rust-resistant and anti-corrosion coating, characterized by: The invention comprises a main agent and a curing agent which are ready to mix and use, and the mass ratio of the main agent to the curing agent is 3-6:1; in parts by mass, the main agent comprises 100 parts of epoxy resin mixture, 10-50 parts of active auxiliary agent, 5-50 parts of mica iron oxide, 10-30 parts of titanium dioxide, 1-20 parts of strontium carbonate and 10-40 parts of aluminum tripolyphosphate; the curing agent comprises 100 parts of benzyl alcohol, 50-100 parts of amine curing agent and 1-20 parts of salicylic acid.

2. The moisture-resistant, rust-resistant and anti-corrosion coating according to claim 1, characterized in that: The epoxy resin mixture is obtained by mixing bisphenol A resin and bisphenol F resin in a mass ratio of 1 to 3:

1.

3. The moisture-resistant, rust-resistant and anti-corrosion coating according to claim 2, characterized in that: The epoxy equivalent of the bisphenol A epoxy resin is 170-200 g / eq; the epoxy equivalent of the bisphenol F epoxy resin is 150-210 g / eq.

4. The moisture-resistant, rust-resistant and anti-corrosion coating according to claim 3, characterized in that: The active additives are dodecyl and tetradecyl glycidyl ether (AGE), and the addition amount of dodecyl and tetradecyl glycidyl ether is 10-50% of the mass of the epoxy resin mixture; the epoxy equivalent weight of AGE is 270-350 g / eq.

5. The moisture-resistant, rust-resistant and anti-corrosion coating according to claim 4, characterized in that: The average diameter of the mica iron oxide is 20-80 μm; the average particle size of titanium dioxide is 2-20 μm; the average particle size of strontium carbonate is 2-50 μm; and the average particle size of aluminum tripolyphosphate is 2-50 μm.

6. The moisture-resistant, rust-resistant and anti-corrosion coating according to claim 5, characterized in that: The main agent also includes one or more of a dispersant, a defoamer, a thickener, a silane compound and an anti-rust pigment.

7. The moisture-resistant, rust-resistant and anti-corrosion coating according to claim 6, characterized in that: The amine curing agent is obtained by mixing aliphatic primary amine and aromatic primary amine in a mass ratio of 1:1-2.

8. The moisture-resistant, rust-resistant and anti-corrosion coating according to claim 7, characterized in that: The aliphatic primary amine is at least one of propylene diamine, ethylene diamine, 2-(aminomethyl)propane-1,3-diamine, etc.; the aromatic primary amine is at least one of phenylenediamine, p-phenylenediamine, and 1-benzofuran-2-amine.

9. The moisture-resistant, rust-resistant and anti-corrosion coating according to claim 8, characterized in that: The curing agent further comprises one or more of a thickener and a preservative.

10. The method for preparing a moisture-resistant, rust-resistant and anti-corrosion coating according to any one of claims 1 to 9, characterized in that: The steps include: Step 1, preparation of the main agent: 100 parts of the epoxy resin mixture, 10-50 parts of the active agent, 5-50 parts of micaceous iron oxide, 10-30 parts of titanium dioxide, 1-20 parts of strontium carbonate and 10-40 parts of aluminum tripolyphosphate are mixed to obtain the main agent; Step 2: Preparation of a curing agent: Mix 100 parts of benzyl alcohol, 50-100 parts of an amine curing agent, and 1-20 parts of salicylic acid to obtain a curing agent; Step 3: Store the main agent and curing agent separately and use them immediately after mixing. The mixing ratio of the main agent to the curing agent is 3~6:1.

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