An environmentally friendly high-performance anti-corrosion coating for contact network steel structural components

Abstract

The present invention belongs to the technical field of anti-corrosion coatings, and specifically discloses an environmentally friendly high-performance anti-corrosion coating for steel structural parts of a contact network. The components and their weight percentages include: 15-35% acrylate-based emulsion, 30-50% arginine-modified conductive metal particles, 10-20% ultrafine zinc powder, 0.5-1% hydroxyethyl cellulose, 0.5-1% dispersant, 0.5-1% defoamer, 0.5-1% n-octanol, and the remainder is water. The anti-corrosion coating of the present invention has the advantages of long-term anti-corrosion and fire protection, long service life, good weather resistance, good decorative properties, and is water-based and environmentally friendly. The construction and preparation involved are simple, the fire protection effect is excellent, and it is environmentally friendly and biodegradable. It can provide safe and environmentally friendly anti-rust protection in VCI applications, is suitable for occasions with high environmental protection requirements, and is suitable for promotion and application.

Description

Technical Field

[0001] The present invention belongs to the technical field of anti-corrosion coatings, and in particular relates to an environmentally friendly high-performance anti-corrosion coating for steel structural parts of a contact network. Background Art

[0002] Vapor Corrosion Inhibitors (VCIs) are chemicals that inhibit metal corrosion in the vapor phase. They produce volatile substances that slowly release into the air, forming trace amounts of vapor-phase compounds. These compounds deposit on the metal surface, forming a molecular-level protective film. This protective film effectively prevents oxygen, water vapor, and other corrosive substances from coming into contact with the metal surface, thereby preventing rust. This prevents the metal surface from coming into contact with corrosive substances such as water vapor and oxygen.

[0003] Common VCI chemical components include amine compounds, amino acids and their derivatives, aldehyde compounds, and organic acid salts. Amine compounds such as sodium naphthenate and sodium benzoate have good volatility and rust prevention effects, making them suitable for use in paper and film. Amino acids such as glycine and proline are environmentally friendly and biodegradable, making them suitable for applications requiring high environmental protection. Aldehydes such as formaldehyde and acetaldehyde offer significant rust prevention effects, but their safety and toxicity should be considered. Organic acid salts such as sodium benzoate and sodium naphthenate offer good rust prevention effects and relatively low toxicity.

[0004] Common VCI chemical compositions for metal corrosion protection primarily consist of amine compounds and organic acid salts. These ingredients provide excellent rust prevention while being relatively easy to handle and safe. However, since organic acid salts often require organic solvents during their synthesis and preparation, or are inherently phenyl-containing compounds, they are often toxic, making these anti-corrosion coatings less environmentally friendly.

[0005] In addition, the addition of these VCIs does not enhance the flame retardant effect, making the anti-corrosion coatings based on such VCIs ineffective in flame retardancy or fire prevention. When used in railway contact networks, high-voltage power transmission, cables and other fields, it is often necessary to apply another layer of fire retardant coating to meet fire protection requirements.

[0006] Therefore, further exploring VCI fillers with flame retardant or fireproof effects and optimizing their preparation process have important practical application value and research significance. Summary of the Invention

[0007] The main purpose of the present invention is to address the deficiencies in the prior art and provide an environmentally friendly, high-performance anti-corrosion coating for contact network steel structural parts. The arginine-modified conductive metal particles contained in the coating formula are simple to synthesize, using water as the solvent, and the arginine and phytic acid in the raw materials can be obtained from biological sources. As a new type of vapor-phase corrosion inhibitor, it can simultaneously enhance the anti-corrosion and flame-retardant effects of the coating. The anti-corrosion and fire-retardant coating has the advantages of long anti-corrosion time, long fire resistance time, excellent adhesion, short drying time, and environmental friendliness, and is suitable for promotion and application.

[0008] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an environmentally friendly high-performance anti-corrosion coating for contact network steel structural parts, the components and their mass percentages include: 15-35% acrylate-based emulsion, 30-50% arginine-modified conductive metal particles, 10-20% ultrafine zinc powder, 0.5-1% hydroxyethyl cellulose, 0.5-1% dispersant, 0.5-1% defoaming agent, 0.5-1% n-octanol, and the rest is water.

[0009] Preferably, the high-performance anti-corrosion coating for the environmentally friendly contact network steel structural parts comprises the following components and their mass percentages: 15-35% acrylate-based emulsion, 30-50% arginine-modified conductive metal particles, 20% ultrafine zinc powder, 0.5% hydroxyethyl cellulose, 0.5% dispersant, 0.5% defoaming agent, 0.5% n-octanol, and the rest water.

[0010] In the above scheme, the acrylate-based emulsion can be selected from acrylate emulsion, methacrylate emulsion, styrene-acrylic emulsion or styrene-acrylic core-shell emulsion, etc.; its solid content is 30-55%, and the coagulation rate is 0.1-2%.

[0011] In the above solution, the particle size of the ultrafine zinc powder is 10-100 microns.

[0012] In the above solution, the dispersant is the wetting dispersant 5040; and the defoaming agent is the silicone defoaming agent 470.

[0013] In the above scheme, the arginine-modified conductive metal particles are prepared from nickel metal particles, arginine, and phytic acid. The preparation method includes the following steps: adding arginine, phytic acid, and nickel metal particles in a mass ratio of (1-2):(1-2):(0.1-1) to a mixed solution of ethanol and water, stirring at a rate of 100-1000 rpm, concentrating at 50-100 degrees Celsius, and then vacuum drying. The resulting yellow liquid is washed with a mixed solution of ethyl acetate and petroleum ether in a mass ratio of 1:1-1:2. Then, it is dried at 50-70 degrees Celsius.

[0014] In the above solution, the size of nickel metal particles is 500nm-500μm.

[0015] The method for preparing the above-mentioned environmentally friendly high-performance anti-corrosion coating for the contact network steel structure comprises the following steps:

[0016] 1) Weigh the raw materials according to the ratio;

[0017] 2) Evenly mix the weighed arginine-modified conductive metal particles, hydroxyethyl cellulose, and ultrafine zinc powder, grind until there is no particle powder, then add water and stir and grind until it is uniform and no obvious particles are present; then add defoamer and dispersant, and continue stirring and grinding until it is uniform;

[0018] 3) Finally, add the acrylate-based emulsion and n-octanol, grind and mix them evenly, and thus obtain the anti-corrosion coating.

[0019] The principle of the present invention is:

[0020] The present invention prepares a water-based, high-performance, environmentally friendly anti-corrosion and fire-retardant coating based on arginine-modified conductive metal particles. The introduction of arginine-modified conductive metal particles improves the anti-corrosion effect of the coating on structural parts (especially the surface of steel structure buildings). Arginine-modified conductive metal particles are made from arginine, phytic acid and nickel metal particles. Nickel particles affect conductivity due to problems such as easy oxidation and agglomeration. Arginine contains amino / carboxylic acid bifunctional groups, and phytic acid is rich in phosphorus hydroxyl groups. A dense coating can be formed by coordination to slowly release amine gases, forming a protective gas phase in a closed space, covering the metal surface, preventing oxygen and moisture from directly contacting the metal, thereby inhibiting rust. After phytate contacts the metal surface, a thin passivation film can be formed by adsorption. This film can effectively prevent the redox reaction from occurring, thereby reducing the occurrence of corrosion. When used in combination, arginine and phytate can improve the anti-rust effect by a synergistic effect, enhancing the performance of gas phase inhibitors. This complex can be better stabilized in the gas phase and evenly distributed on the metal surface. Arginine-modified conductive metal particles react with the coating matrix during combustion. Phytic acid, an acid source, releases phosphates that react with the matrix, while arginine, a nitrogen source, releases non-flammable gases, resulting in an expanded, porous carbon layer. Furthermore, both arginine and phytic acid are naturally occurring, environmentally friendly, and biodegradable, making them safe and environmentally friendly for rust prevention in VCI applications, making them suitable for environmentally sensitive applications.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1) The anticorrosive coating obtained by the present invention has the advantages of long-term anticorrosion, long-term fire protection, long service life, good weather resistance, good decorative properties, water-based and environmental protection; and the construction and preparation involved are simple, the fire protection effect is excellent, and it is suitable for promotion and application;

[0023] 2) The arginine-modified conductive metal particles described in the present invention can enhance the flame retardancy of conventional anti-corrosion coatings, making such VCI-based anti-corrosion coatings flame retardant or fireproof, and are suitable for use in areas where fire risks may exist, such as high-voltage power transmission and cables.

[0024] 3) Compared with traditional VCI vapor phase corrosion inhibitors, arginine-modified conductive metal particles have advantages such as environmental friendliness and biodegradability, which can provide a new approach for the preparation of environmentally friendly anti-corrosion and fire retardant coatings;

[0025] 4) Arginine and phytic acid are biomass materials that are easily available, inexpensive, and environmentally friendly. In addition, the coating uses water as a solvent, which is environmentally friendly. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a comparison of the morphology of the anti-corrosion coatings obtained in Example 1 and Comparative Example 1 after a simulated cross-bay area salt spray test (5% sodium chloride aqueous solution, adding hydrochloric acid to adjust the pH to 6.0-6.3, 7 days);

[0027] Figure 2 The large plate combustion method back temperature curves of the anti-corrosion coatings obtained in Example 1 and Comparative Example 1;

[0028] Figure 3 The Nyquist spectra of the anti-corrosion coatings obtained in Example 1 and Comparative Example 1 are shown;

[0029] Figure 4 The Bode spectra of the anti-corrosion coatings obtained in Example 1 and Comparative Example 1 are shown;

[0030] Figure 5 The Bode spectra of the anti-corrosion coatings obtained in Example 1 and Comparative Example 1 are shown. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0032] In the following examples, the dispersant used is wetting dispersant 5040; the defoaming agent is silicone defoaming agent 470.

[0033] In the following examples, the acrylate-based emulsion used is an acrylate emulsion, and its preparation method includes the following steps:

[0034] 1) 1.0 g of alkylphenol polyoxyethylene ether and 2.0 g of sodium lauryl sulfate were dissolved in 90 ml of deionized water to prepare an emulsifier aqueous solution, which was then divided into three portions of 35 ml, 30 ml, and 25 ml; 50 g of n-butyl acrylate and 10 g of methyl methacrylate were added to 30 ml of the emulsifier aqueous solution, stirred and mixed at room temperature, and pre-emulsified for 1 hour to prepare a core pre-emulsion; 10 g of n-butyl acrylate, 30 g of methyl methacrylate, and 2.4 g of methacrylic acid were added to 30 ml of the emulsifier aqueous solution, stirred and mixed at room temperature, and pre-emulsified for 2 hours to prepare a shell pre-emulsion; 0.3 g of sodium bicarbonate was dissolved in 25 ml of the emulsifier aqueous solution and stirred to dissolve to prepare a buffer aqueous solution; 0.5 g of potassium persulfate was added to 30 ml of deionized water and stirred to dissolve to prepare an initiator aqueous solution;

[0035] 2) Preparation of seed emulsion: In a reaction vessel, add a buffer solution, 1 / 3 volume of an initiator solution, and 1 / 2 volume of a core pre-emulsion solution in sequence while stirring. Raise the temperature to 70°C. When the emulsion emits a large amount of blue light, maintain the temperature for 0.5 h to obtain the seed emulsion.

[0036] 3) Core layer polymerization: When the seed emulsion is finished being kept warm, slowly drip the remaining core pre-emulsion and 1 / 3 of the initiator aqueous solution into the seed emulsion. The addition should be completed within 1 hour. The temperature should be controlled to 80°C and kept warm for 0.5 hours to obtain the core layer emulsion.

[0037] 4) Shell Polymerization: At the end of the core emulsion incubation period, the remaining initiator aqueous solution and shell pre-emulsion were added dropwise over 1.5 hours. The mixture was then heated to 85°C and incubated for 0.5 hours. The mixture was then cooled naturally to 40°C. The pH was adjusted to 8 and the mixture was passed through a 200-mesh sieve to obtain an acrylic core-shell emulsion with a solids content of 41% and a coagulation rate of 0.34%.

[0038] In the following examples, the preparation method of arginine-modified conductive metal particles includes the following steps:

[0039] Arginine, phytic acid, and nickel metal particles were added to a mixture of ethanol and water (volume ratio: 1:1) in a mass ratio of 1.5:1:0.3. The nickel metal particles were 500 nm in size and stirred at 300 rpm. The mixture was concentrated at 80 degrees Celsius and then vacuum-dried. The resulting yellow liquid was washed with a mixture of ethyl acetate and petroleum ether in a mass ratio of 1:1.33 and then dried at 60 degrees Celsius.

[0040] Example 1

[0041] An anti-corrosion coating, comprising the following components in percentage by mass: 35% acrylate-based emulsion, 30% arginine-modified conductive metal particles, 20% ultrafine zinc powder, 0.5% hydroxyethyl cellulose, 0.5% dispersant, 0.5% defoamer, 0.5% n-octanol, and 13% water; a preparation method thereof comprising the following steps:

[0042] 1) Weigh the raw materials according to the above ratio requirements;

[0043] 2) Grinding the weighed arginine-modified conductive metal particles, hydroxyethyl cellulose, and ultrafine zinc powder until there are no particles, then adding water to thoroughly grind and mix; then adding a defoamer and a dispersant, and continuing to fully grind;

[0044] 3) Finally, add the acrylate-based emulsion and n-octanol, grind and mix thoroughly to obtain the anti-corrosion coating.

[0045] Example 2

[0046] An anti-corrosion coating, the preparation method of which is roughly the same as that of Example 1, except that the components and their mass percentages are: 25% acrylate-based emulsion, 40% arginine-modified conductive metal particles, 20% ultrafine zinc powder, 0.5% hydroxyethyl cellulose, 0.5% dispersant, 0.5% defoamer, 0.5% n-octanol, and 13% water.

[0047] Example 3

[0048] An anti-corrosion coating, the preparation method of which is roughly the same as that of Example 1, except that the components and their mass percentages are: 15% acrylate-based emulsion, 50% arginine-modified conductive metal particles, 20% ultrafine zinc powder, 0.5% hydroxyethyl cellulose, 0.5% dispersant, 0.5% defoamer, 0.5% n-octanol, and 13% water.

[0049] Comparative Example 1

[0050] A coating, the preparation method of which is substantially the same as that of Example 1, except that the components and their mass percentages are: 65% acrylate-based emulsion, 20% ultrafine zinc powder, 0.5% hydroxyethyl cellulose, 0.5% dispersant, 0.5% defoamer, 0.5% n-octanol, and 13% water.

[0051] Comparative Example 2

[0052] A coating, the preparation method of which is substantially the same as that of Example 1, except that the components and their mass percentages are: 85% acrylate-based emulsion, 0.5% hydroxyethyl cellulose, 0.5% dispersant, 0.5% defoamer, 0.5% n-octanol, and 13% water.

[0053] The anticorrosive coatings obtained in Examples 1 to 3 and Comparative Examples 1 to 2 were subjected to a simulated cross-bay area environment salt spray test and a fire resistance test, and the results are shown in Table 1. All steel structure substrates tested were Q325 steel.

[0054] Table 1 Performance test results of the intumescent fire retardant coatings obtained in Examples 1 to 3 and Comparative Examples 1 to 2

[0055]

[0056] Surface morphology after salt spray corrosion resistance: Check the rust condition of the coating surface according to the requirements of GB / T 1766-2008 "Rating method for aging of paint and varnish coatings".

[0057] The evaluation criteria are as follows:

[0058] Ri0: 0% rust area, no rust.

[0059] Ri1: 0.05% rust area, very light rust.

[0060] Ri2: 0.5% rusted area, slightly rusted.

[0061] Ri3: 1% rusted area, obvious rust.

[0062] Ri4: 8% rust area, large rust.

[0063] Ri5: 40%-50% rusted area, severe rust.

[0064] Figure 1 This is a comparison of the morphologies of the anti-corrosion coatings obtained in Example 1 and Comparative Example 1 before and after the simulated cross-bay environmental salt spray test. It can be seen from the figure that there are no obvious signs of corrosion on the surface of Example 1 before the test, while there are obviously a large number of white corrosion products on the surface of Comparative Example 1 after the test.

[0065] Figure 2 The back plate temperature curves of the anti-corrosion coatings obtained in Example 1 and Comparative Example 1 are obtained using a large plate combustion method. The figure shows that the back plate temperature of Example 1 is significantly lower than that of Comparative Example 1 and can be maintained below 250 degrees Celsius for 60 minutes.

[0066] The barrier properties of Example 1 and Comparative Example 1 were tested. The Example 1 and Comparative Example 1 were immersed in a 3.5% NaCl aqueous solution for 7 days, and then subjected to electrochemical impedance spectroscopy test. The test results are shown in the attached specification. Figure 3 、 4 , as shown in 5.

[0067] In the Nyquist diagram, the larger the radius of the capacitive reactance arc in the high frequency region, the better the barrier performance of the coating, which corresponds to better corrosion resistance. Figure 3 As shown, the order of the capacitive reactance arc radius in the high-frequency region is that Example 1 is greater than Comparative Example 1. It can be seen that the shielding performance of the coating obtained in Example 1 is better than that of Comparative Example 1.

[0068] In the Bode spectrum, the low-frequency impedance modulus (|Z|0.01Hz) in the electrochemical impedance test is a semi-quantitative indicator of the coating's ability to shield the penetration of corrosive media (water, oxygen, chloride ions, etc.). The larger the impedance modulus, the stronger the corresponding shielding performance against penetration of corrosive substances. Figure 4 As shown in Figure 5, the low-frequency impedance modulus of the coating obtained in Example 1 is obviously greater than that in Comparative Example 1, so its shielding effect on corrosive media is better.

[0069] These results demonstrate that the environmentally friendly, high-performance anti-corrosion coating for contact network steel structural components obtained by the present invention exhibits excellent corrosion resistance and flame retardancy, is environmentally friendly and pollution-free, exhibits excellent durability, and exhibits excellent compatibility and adsorption with the substrate, effectively balancing other substrate properties. The preparation method disclosed herein is simple and effective, with broad applicability.

[0070] Obviously, the above embodiments are merely examples for illustrative purposes and are not intended to limit the implementation methods. Those skilled in the art will readily appreciate that other variations or modifications based on the above descriptions are possible. It is not necessary and impossible to enumerate all implementation methods here. However, any obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. An environmentally friendly high-performance anti-corrosion coating for steel structural parts of contact network, characterized in that: The components and their mass percentages include: 15-35% acrylate-based emulsion, 30-50% arginine-modified conductive metal particles, 10-20% ultrafine zinc powder, 0.5-1% hydroxyethyl cellulose, 0.5-1% dispersant, 0.5-1% defoamer, 0.5-1% n-octanol, and the remainder is water; the arginine-modified conductive metal particles are characterized in that the arginine-modified conductive metal particles are made of arginine, phytic acid and nickel metal particles; the nickel metal particles have a size of 500nm-500μm; The arginine-modified conductive metal particle synthesis method comprises the following steps: adding arginine, phytic acid, and nickel metal particles in a mass ratio of (1-2):(1-2):(0.1-1) to a mixed solution of ethanol and water, stirring at a rate of 100-1000 rpm, concentrating at 50-100 degrees Celsius, and then vacuum drying. The resulting yellow liquid is washed with a mixed solution of ethyl acetate and petroleum ether in a mass ratio of 1:1-1:2, and then dried.

2. The high-performance anti-corrosion coating for environmentally friendly contact network steel structural parts according to claim 1 is characterized in that: The components and their mass percentages include: 15-35% of acrylate-based emulsion, 30-50% of arginine-modified conductive metal particles, 20% of ultrafine zinc powder, 0.5% of hydroxyethyl cellulose, 0.5% of dispersant, 0.5% of defoaming agent, 0.5% of n-octanol, and the rest of water.

3. The high-performance anti-corrosion coating for environmentally friendly contact network steel structural parts according to claim 1 is characterized in that: The acrylate-based emulsion includes one or more of acrylate emulsion, methacrylate emulsion, styrene-acrylic emulsion or styrene-acrylic core-shell emulsion; the acrylate-based emulsion has a solid content of 30-55% and a coagulation rate of 0.1-2%.

4. The high-performance anti-corrosion coating for environmentally friendly contact network steel structural parts according to claim 1 is characterized in that: The dispersant is wetting dispersant 5040; the defoaming agent is silicone defoaming agent 470.

5. The high-performance anti-corrosion coating for environmentally friendly contact network steel structural parts according to claim 1 is characterized in that: The particle size of the ultrafine zinc powder is 10-100 microns.

6. The method for preparing the high-performance anti-corrosion coating for the environmentally friendly contact network steel structure according to any one of claims 1 to 5, characterized in that: The steps include: 1) Weigh the raw materials according to the ratio; 2) Evenly mix the arginine-modified conductive metal particles, hydroxyethyl cellulose, and ultrafine zinc powder, grind until there is no particle powder, then add water and stir and grind until it is uniform and no obvious particles are present; then add the defoamer and dispersant, and continue stirring and grinding until it is uniform; 3) Finally, add the acrylate-based emulsion and n-octanol, grind and mix them evenly to obtain the anti-corrosion coating.

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