A UV-curable anti-corrosion coating and its preparation method

Abstract

This invention relates to the field of coating preparation technology, and discloses a UV-curable anti-corrosion coating and its preparation method. The UV-curable anti-corrosion coating of this invention comprises the following raw materials in parts by weight: 45-65 parts epoxy acrylate resin, 1.5-3 parts modified MXene, 0.5-1.5 parts antibacterial nanospheres, 5-10 parts defoamer, 0.1-0.5 parts leveling agent, 0-0.3 parts curing agent, 4-8 parts photoinitiator, and 20-25 parts deionized water. The modified MXene of this invention can effectively block the erosion of the substrate by corrosive media such as acids, alkalis, and salt spray; the antibacterial nanospheres can effectively inhibit the adhesion and reproduction of bacteria and other harmful microorganisms, thus fundamentally preventing microbial corrosion from damaging the coating.

Description

Technical Field

[0001] This invention relates to the field of coating preparation technology, specifically to a UV-curable anti-corrosion coating and its preparation method. Background Technology

[0002] With the continuous advancement of global industrial modernization, the demands for corrosion protection of metal materials in fields such as marine engineering, rail transportation, petrochemicals, and equipment manufacturing are becoming increasingly stringent. Coatings are currently the most widely used and economical means of metal corrosion protection. Among them, UV curing technology, as a mature and environmentally friendly green manufacturing technology, has achieved rapid development and large-scale application in the coatings field due to its outstanding advantages such as fast curing speed, high production efficiency, and high energy utilization. However, at the same time, its comprehensive performance still faces many technical bottlenecks in high-end applications such as heavy-duty anti-corrosion. Anti-corrosion coatings need to withstand harsh conditions such as acid and alkali media, salt spray, and humid heat for extended periods. However, conventional UV-cured resins contain a large number of easily hydrolyzed polar groups such as ester bonds. Under long-term service in corrosive environments, these groups are prone to molecular chain degradation and cross-linking structure destruction, leading to coating failures such as blistering, peeling, and substrate corrosion. Furthermore, in applications such as marine engineering and water treatment, microbial adhesion can trigger microbial corrosion, accelerating coating failure and substrate corrosion. Therefore, endowing anti-corrosion coatings with excellent antibacterial properties has become an important development direction for the industry.

[0003] Patent application number 201310563912.5 discloses an epoxy resin anticorrosive coating that uses one or more of isothiazolinone derivatives, benzimidazole esters, and Dowshire-75 as preservatives, improving the coating's corrosion resistance. However, the direct physical blending of multiple organic preservatives results in poor compatibility and a lack of chemical bonding, making synergistic effects difficult to achieve and leading to unstable long-term anticorrosive effects. Patent application number 202211457774.8 discloses an antibacterial powder coating and its preparation method, using nano-silver powder as the main antibacterial agent. However, its cost is high, it is prone to agglomeration and poor dispersibility, and it is easily oxidized in air, affecting its appearance. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a UV-curable anti-corrosion coating and its preparation method.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A UV-curable anti-corrosion coating comprises the following raw materials in parts by weight: 45-65 parts epoxy acrylate resin, 1.5-3 parts modified MXene, 0.5-1.5 parts antibacterial nanospheres, 5-10 parts defoamer, 0.1-0.5 parts leveling agent, 0-0.3 parts curing agent, 4-8 parts photoinitiator, and 20-25 parts deionized water;

[0007] The defoamer is at least one of BYK-024, SF-8091, and XW6567;

[0008] The leveling agent is at least one of BYK-333 and BYK-346;

[0009] The curing agent is at least one of Y-593, Y-3315, Y-3318, and Y-1619;

[0010] The photoinitiator is at least one of photoinitiator 2959, photoinitiator 500, and photoinitiator 659;

[0011] The modified MXene is prepared by the following steps:

[0012] Step A1: Mix 4,6-dihydroxy-2-mercaptopyrimidine, 5wt% sodium hydroxide aqueous solution and 1,4-dioxane, stir at 50°C for 30 min, then add 4-bromomethylbenzyl alcohol dropwise, stir at 50°C for 4 h, cool to room temperature, filter, wash, dry and recrystallize to obtain intermediate product 1;

[0013] Furthermore, the ratio of 4,6-dihydroxy-2-mercaptopyrimidine, sodium hydroxide aqueous solution, 1,4-dioxane, and 4-bromomethylbenzyl alcohol is 0.19-0.39 mol: 160-320 mL: 400-700 mL: 0.2-0.4 mol;

[0014] In step A1, 4,6-dihydroxy-2-mercaptopyrimidine and 4-bromomethylbenzyl alcohol undergo a nucleophilic substitution reaction, introducing a hydroxyl group into the system and providing reaction conditions for the subsequent esterification reaction. The oxygen and nitrogen atoms contained in the pyrimidinone structure readily form coordinate bonds with empty metal orbitals to form stable complexes, enhancing adsorption stability. Furthermore, physical or chemical adsorption can occur on the metal surface, forming a dense protective film that isolates the corrosive medium from contact with the metal.

[0015] Step A2: Mix intermediate product 1 with toluene, stir and heat to 80°C, add boron trifluoride-diethyl ether complex, add 2,3-epoxypropyltrimethylammonium chloride solution dropwise, after the addition is complete, reflux for 3 hours, and distill under reduced pressure to obtain intermediate product 2.

[0016] Furthermore, the ratio of intermediate 1, toluene, boron trifluoride-diethyl ether complex, and 2,3-epoxypropyltrimethylammonium chloride solution is 0.1-0.3 mol: 150-200 mL: 0.02-0.08 g: 100-150 mL;

[0017] Furthermore, the 2,3-epoxypropyltrimethylammonium chloride solution is prepared by mixing 2,3-epoxypropyltrimethylammonium chloride and anhydrous methanol at a volume ratio of 0.115-0.345 mol: 50-150 mL;

[0018] In step A2, intermediate product 1 and 2,3-epoxypropyltrimethylammonium chloride undergo a ring-opening reaction, introducing the quaternary ammonium salt into the system. This provides reaction conditions for the subsequent ion exchange reaction, and the quaternary ammonium salt can form an adsorption film on the metal surface, inhibiting the penetration of oxygen, moisture and ions, and improving the corrosion resistance of the coating.

[0019] Step A3: Mix lithium fluoride and 9 mol / L hydrochloric acid solution, stir for 20 min, then add Ti3AlC2, and etch in a 35℃ water bath for 48 h. Collect the mixture by centrifugation, add deionized water and shake well. Repeat centrifugation several times until the pH of the supernatant is greater than 6. Transfer the obtained precipitate to 100 mL of deionized water, sonicate in an ice-water bath under nitrogen protection for 1 h, and centrifuge for 1 h to obtain MXene suspension, which is intermediate product 3.

[0020] Furthermore, the ratio of lithium fluoride, hydrochloric acid solution, and Ti3AlC2 used is 2-3g: 40-50mL: 2-3g;

[0021] In step A3, an MXene suspension is prepared by chemical etching to provide reaction conditions for the subsequent grafting reaction.

[0022] Step A4: Mix intermediate product 2 and 70wt% ethanol aqueous solution, add intermediate product 3, stir at 30℃ for 24h, then centrifuge and wash, vacuum dry to obtain modified MXene;

[0023] Furthermore, the ratio of intermediate 2, aqueous ethanol solution, and intermediate 3 is 0.001-0.003 mol: 20-60 mL: 20 mL;

[0024] In step A4, intermediate product 2 is intercalated into MXene through ion exchange and electrostatic interaction. MXene has excellent mechanical properties and biocompatibility. Its layered structure can effectively improve the protective and mechanical properties of the coating and prevent the penetration of corrosive media. When quaternary ammonium salt is intercalated into the MXene interlayer, it can expand the interlayer spacing, improve dispersibility, and work synergistically with pyrimidinone to achieve a dual effect of physical barrier and chemical adsorption, effectively inhibiting the corrosion reaction and significantly improving corrosion inhibition performance and long-term stability.

[0025] The antibacterial nanospheres are prepared by the following steps:

[0026] Step B1: Mix methacrylic acid and dichloromethane, then add EDCI (1-ethyl-3-(3-dimethylaminopropyl)carboimide hydrochloride) and 4-dimethylaminopyridine, stir for 1 h, add dextrorotatory borneol, stir at room temperature for 6 h, after the reaction is complete, wash three times with 1 mol / L hydrochloric acid solution, saturated sodium bicarbonate solution and saturated sodium chloride solution, then dry, filter, rotary evaporate, purify, rotary evaporate and vacuum dry to obtain borneol acrylate;

[0027] Furthermore, the volume ratio of methacrylic acid, dichloromethane, EDCI, 4-dimethylaminopyridine, dextrorotatory borneol, hydrochloric acid solution, saturated sodium bicarbonate solution, and saturated sodium chloride solution is 0.1-0.2 mol: 400-600 mL: 0.2-0.4 mol: 0.02-0.04 mol: 0.12-0.24 mol: 600 mL: 600 mL: 600 mL;

[0028] In step B1, methacrylic acid and dextrorotatory borneol undergo esterification, introducing double bonds into the system and providing reaction conditions for subsequent polymerization. Borneol can destroy the cell membranes of bacteria or fungi, interfere with their metabolic processes, inhibit microbial growth, and even lead to death.

[0029] Step B2: Mix 4-vinylbenzaldehyde, thiazolidinedione and anhydrous ethanol, stir, add hexahydropyridine and glacial acetic acid, reflux at 80°C for 24 h, precipitate the solid with water, filter and dry to obtain vinylthiazolidinedione.

[0030] Furthermore, the molar ratio of 4-vinylbenzaldehyde, thiazolidinedione, anhydrous ethanol, hexahydropyridine, and glacial acetic acid is 0.1-0.2 mol: 0.19-0.38 mol: 200-300 mL: 0.005-0.01 mol: 0.005-0.01 mol;

[0031] In step B2, 4-vinylbenzaldehyde and thiazolidinedione undergo a nucleophilic addition-elimination reaction, introducing a double bond into the system and providing reaction conditions for the subsequent polymerization reaction. Thiazolidinediones have broad-spectrum antibacterial properties, and the sulfur atom in them readily binds to the sulfhydryl group in cysteine ​​through hydrogen bonds. Cysteine ​​is an essential amino acid for bacterial growth and reproduction, so the reproduction and growth of bacteria are inhibited when sulfur atoms are present.

[0032] Step B3: Mix methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, sodium dodecylbenzenesulfonate, and deionized water to obtain a mixture. Place the mixture in an 85°C water bath. Mix borneol acrylate and vinylthiazolidinedione and add them to the mixture. Then, add 0.22wt% KPS aqueous solution dropwise. After the addition is complete, continue the reaction at 85°C for 3 hours. Dialyze the resulting emulsion and freeze-dry it to obtain thiazolidinedione-borneol-based cationic nanospheres, which are antibacterial nanospheres.

[0033] Furthermore, the ratio of the amounts of methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, sodium dodecylbenzenesulfonate, deionized water, bornyl acrylate, vinylthiazolidinedione, and KPS aqueous solution is 2-4 mmol: 1.5-3 mmol: 0.03-0.06 g: 30-60 mL: 3-6 mmol: 8-16 mmol: 20-40 mL;

[0034] In step B3, a one-pot emulsion polymerization method is used to copolymerize methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, bornyl acrylate, and vinylthiazolidinedione. Thiazolidinedione and bornyl group have hydrophobic and antibacterial properties, quaternary ammonium salt has antibacterial adhesion properties, and N,N'-methylenebisacrylamide, as a crosslinking monomer, increases the chain length of the polymer, increases the specific surface area of ​​the synthesized nanospheres, and improves the antibacterial activity. It can make them adhere to the cell membrane, interfere with the pathways of important molecules, and improve the antibacterial performance.

[0035] A method for preparing a UV-curable anti-corrosion coating includes the following steps:

[0036] Step S1: Weigh the raw materials according to the weight parts, add epoxy acrylate resin to the mixing tank, add defoamer, leveling agent and curing agent and stir, disperse at high speed for 30-50 minutes;

[0037] Step S2: After the raw materials in the mixing tank are stirred evenly and ground thoroughly, reduce the stirring speed, add modified MXene and antibacterial nanospheres according to the ratio and stir, gradually increase the stirring speed to disperse them evenly;

[0038] Step S3: Add photoinitiator and deionized water to the mixing tank in the mixing process according to the ratio, adjust the viscosity of the coating, and obtain UV-curable anti-corrosion coating.

[0039] The beneficial effects of this invention are:

[0040] The UV-curable anti-corrosion coating of this invention can be widely used in engineering fields with stringent requirements for corrosion resistance, such as marine engineering, steel structure construction, and chemical equipment. This UV-curable anti-corrosion coating can achieve rapid curing and film formation through ultraviolet light irradiation. Simultaneously, relying on modified MXene, it effectively blocks the erosion of the substrate by corrosive media such as acids, alkalis, and salt spray, preventing problems such as rust, perforation, coating peeling, and biofouling on metal and non-metal substrates under complex service environments. Antibacterial nanospheres can effectively inhibit the adhesion and reproduction of various bacteria, molds, and other harmful microorganisms, fundamentally blocking the continuous damage of the protective system caused by microbial corrosion. Compared with existing technologies, the UV-curable anti-corrosion coating prepared by this invention has excellent comprehensive protective performance and long-term stability, meeting the requirements of current national standards for coatings, and has broad application prospects and industrialization value.

[0041] The modified MXene of this invention first undergoes a nucleophilic substitution reaction between 4,6-dihydroxy-2-mercaptopyrimidine and 4-bromomethylbenzyl alcohol. The oxygen and nitrogen atoms in the pyrimidinone structure readily form coordinate bonds with empty metal orbitals, creating stable complexes that enhance adsorption stability. Furthermore, it can undergo physical or chemical adsorption on the metal surface, forming a dense protective film that isolates corrosive media from contact with the metal. Subsequently, a ring-opening reaction is used to introduce a quaternary ammonium salt into the system. The quaternary ammonium salt can form an adsorption film on the metal surface, inhibiting the penetration of oxygen, moisture, and ions, thereby improving the corrosion resistance of the coating. Subsequently, an MXene suspension was prepared through a chemical etching reaction. Finally, intermediate product 2 was intercalated into MXene through ion exchange and electrostatic interaction. MXene has excellent mechanical properties and biocompatibility. Its layered structure can effectively improve the protective and mechanical properties of the coating and prevent the penetration of corrosive media. When quaternary ammonium salts are intercalated into the MXene interlayer, the interlayer spacing can be expanded, the dispersibility can be improved, and the synergistic effect with pyrimidinone can achieve the dual effects of physical barrier and chemical adsorption, effectively inhibiting the corrosion reaction and greatly improving the corrosion inhibition performance and long-term stability.

[0042] The antibacterial nanospheres of this invention first undergo an esterification reaction between methacrylic acid and dextrorotatory borneol. Borneol can disrupt the cell membranes of bacteria or fungi, interfere with their metabolic processes, inhibit microbial growth, and even lead to death. Then, a nucleophilic addition-elimination reaction is performed between 4-vinylbenzaldehyde and thiazolidinedione. Thiazolidinediones have broad-spectrum antibacterial properties, and their sulfur atoms readily bind to the sulfhydryl groups in cysteine ​​via hydrogen bonds. Cysteine ​​is an essential amino acid for bacterial growth and reproduction; therefore, the presence of sulfur atoms inhibits bacterial reproduction and growth. Finally, a one-pot emulsion polymerization method was used to copolymerize methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, bornyl acrylate, and vinylthiazolidinedione. Thiazolidinedione and bornyl group have hydrophobic and antibacterial properties, quaternary ammonium salt has antibacterial adhesion properties, and N,N'-methylenebisacrylamide, as a crosslinking monomer, increases the chain length of the polymer, resulting in a larger specific surface area of ​​the synthesized nanospheres and improved antibacterial activity. This allows them to adhere to the cell membrane, interfere with the pathways of important molecules, and improve antibacterial performance. Detailed Implementation

[0043] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Example 1: Modified MXene was prepared by the following steps:

[0045] Step A1: Mix 4,6-dihydroxy-2-mercaptopyrimidine, 5wt% sodium hydroxide aqueous solution, and 1,4-dioxane, stir at 50°C for 30 min, then add 4-bromomethylbenzyl alcohol dropwise, stir at 50°C for 4 h, cool to room temperature, filter, wash, dry, and recrystallize to obtain the intermediate product. The molar ratio of 1,4,6-dihydroxy-2-mercaptopyrimidine, sodium hydroxide aqueous solution, 1,4-dioxane, and 4-bromomethylbenzyl alcohol is 0.19 mol: 160 mL: 400 mL: 0.2 mol.

[0046] Step A2: Mix intermediate product 1 and toluene, stir and heat to 80℃, add boron trifluoride-diethyl ether complex, and dropwise add 2,3-epoxypropyltrimethylammonium chloride solution. After the addition is complete, reflux for 3 hours, and distill under reduced pressure to obtain intermediate product 2. The ratio of intermediate product 1, toluene, boron trifluoride-diethyl ether complex and 2,3-epoxypropyltrimethylammonium chloride solution is 0.1 mol: 150 mL: 0.02 g: 100 mL. The 2,3-epoxypropyltrimethylammonium chloride solution is prepared by mixing 2,3-epoxypropyltrimethylammonium chloride and anhydrous methanol at a ratio of 0.115 mol: 50 mL.

[0047] Step A3: Mix lithium fluoride and 9 mol / L hydrochloric acid solution, stir for 20 min, then add Ti3AlC2, and etch in a 35℃ water bath for 48 h. Collect the mixture by centrifugation, add deionized water and shake well. Repeat centrifugation several times until the pH of the supernatant is greater than 6. Transfer the obtained precipitate to 100 mL of deionized water, sonicate in an ice-water bath under nitrogen protection for 1 h, and centrifuge for 1 h to obtain MXene suspension, which is intermediate product 3. The ratio of lithium fluoride, hydrochloric acid solution and Ti3AlC2 is 2 g: 40 mL: 2 g.

[0048] Step A4: Mix intermediate product 2 and 70wt% ethanol aqueous solution, add intermediate product 3, stir at 30℃ for 24h, then centrifuge and wash, vacuum dry to obtain modified MXene. The ratio of intermediate product 2, ethanol aqueous solution and intermediate product 3 is 0.001mol:20mL:20mL.

[0049] Antibacterial nanospheres are prepared by the following steps:

[0050] Step B1: Mix methacrylic acid and dichloromethane, then add EDCI and 4-dimethylaminopyridine, stir for 1 h, add dextrorotatory borneol, stir at room temperature for 6 h. After the reaction is complete, wash three times with 1 mol / L hydrochloric acid solution, saturated sodium bicarbonate solution, and saturated sodium chloride solution, then dry, filter, rotary evaporate, purify, rotary evaporate, and vacuum dry to obtain borneol acrylate. The ratio of methacrylic acid, dichloromethane, EDCI, 4-dimethylaminopyridine, dextrorotatory borneol, hydrochloric acid solution, saturated sodium bicarbonate solution, and saturated sodium chloride solution is 0.1 mol: 400 mL: 0.2 mol: 0.02 mol: 0.12 mol: 600 mL: 600 mL: 600 mL.

[0051] Step B2: Mix 4-vinylbenzaldehyde, thiazolidinedione, and anhydrous ethanol, stir, add hexahydropyridine and glacial acetic acid, reflux at 80°C for 24 h, precipitate the solid with water, filter and dry to obtain vinylthiazolidinedione. The molar ratio of 4-vinylbenzaldehyde, thiazolidinedione, anhydrous ethanol, hexahydropyridine, and glacial acetic acid is 0.1 mol: 0.19 mol: 200 mL: 0.005 mol: 0.005 mol.

[0052] Step B3: Mix methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, sodium dodecylbenzenesulfonate, and deionized water to obtain a mixture. Place the mixture in an 85°C water bath. Mix borneol acrylate and vinylthiazolidinedione and add them to the mixture. Then, add 0.22wt% KPS aqueous solution dropwise. After the addition is complete, continue the reaction at 85°C for 3 hours. Dialyze the resulting emulsion and freeze-dry it to obtain thiazolidinedione-borneol-based cationic nanospheres, which are antibacterial nanospheres. The ratio of methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, sodium dodecylbenzenesulfonate, deionized water, borneol acrylate, vinylthiazolidinedione, and KPS aqueous solution is 2mmol:1.5mmol:0.03g:30mL:3mmol:8mmol:20mL.

[0053] Example 2: Modified MXene was prepared by the following steps:

[0054] Step A1: Mix 4,6-dihydroxy-2-mercaptopyrimidine, 5wt% sodium hydroxide aqueous solution, and 1,4-dioxane, stir at 50°C for 30 min, then add 4-bromomethylbenzyl alcohol dropwise, stir at 50°C for 4 h, cool to room temperature, filter, wash, dry, and recrystallize to obtain the intermediate product. The molar ratio of 1,4,6-dihydroxy-2-mercaptopyrimidine, sodium hydroxide aqueous solution, 1,4-dioxane, and 4-bromomethylbenzyl alcohol is 0.29 mol: 240 mL: 550 mL: 0.3 mol.

[0055] Step A2: Mix intermediate product 1 and toluene, stir and heat to 80℃, add boron trifluoride-diethyl ether complex, and dropwise add 2,3-epoxypropyltrimethylammonium chloride solution. After the addition is complete, reflux for 3 hours, and distill under reduced pressure to obtain intermediate product 2. The ratio of intermediate product 1, toluene, boron trifluoride-diethyl ether complex and 2,3-epoxypropyltrimethylammonium chloride solution is 0.2 mol: 175 mL: 0.05 g: 125 mL. The 2,3-epoxypropyltrimethylammonium chloride solution is prepared by mixing 2,3-epoxypropyltrimethylammonium chloride and anhydrous methanol at a ratio of 0.23 mol: 100 mL.

[0056] Step A3: Mix lithium fluoride and 9 mol / L hydrochloric acid solution, stir for 20 min, then add Ti3AlC2, and etch in a 35℃ water bath for 48 h. Collect the mixture by centrifugation, add deionized water and shake well. Repeat centrifugation several times until the pH of the supernatant is greater than 6. Transfer the obtained precipitate to 100 mL of deionized water, sonicate in an ice-water bath under nitrogen protection for 1 h, and centrifuge for 1 h to obtain MXene suspension, which is intermediate product 3. The ratio of lithium fluoride, hydrochloric acid solution and Ti3AlC2 is 2.5 g: 45 mL: 2.5 g.

[0057] Step A4: Mix intermediate product 2 and 70wt% ethanol aqueous solution, add intermediate product 3, stir at 30℃ for 24h, then centrifuge and wash, vacuum dry to obtain modified MXene. The ratio of intermediate product 2, ethanol aqueous solution and intermediate product 3 is 0.002mol:40mL:20mL.

[0058] Antibacterial nanospheres are prepared by the following steps:

[0059] Step B1: Mix methacrylic acid and dichloromethane, then add EDCI and 4-dimethylaminopyridine, stir for 1 h, add dextrorotatory borneol, stir at room temperature for 6 h. After the reaction is complete, wash three times with 1 mol / L hydrochloric acid solution, saturated sodium bicarbonate solution, and saturated sodium chloride solution, then dry, filter, rotary evaporate, purify, rotary evaporate, and vacuum dry to obtain borneol acrylate. The ratio of methacrylic acid, dichloromethane, EDCI, 4-dimethylaminopyridine, dextrorotatory borneol, hydrochloric acid solution, saturated sodium bicarbonate solution, and saturated sodium chloride solution is 0.15 mol: 500 mL: 0.3 mol: 0.03 mol: 0.18 mol: 600 mL: 600 mL: 600 mL.

[0060] Step B2: Mix 4-vinylbenzaldehyde, thiazolidinedione, and anhydrous ethanol, stir, add hexahydropyridine and glacial acetic acid, reflux at 80°C for 24 h, precipitate the solid with water, filter and dry to obtain vinylthiazolidinedione. The molar ratio of 4-vinylbenzaldehyde, thiazolidinedione, anhydrous ethanol, hexahydropyridine, and glacial acetic acid is 0.15 mol: 0.285 mol: 250 mL: 0.0075 mol: 0.0075 mol.

[0061] Step B3: Mix methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, sodium dodecylbenzenesulfonate, and deionized water to obtain a mixture. Place the mixture in an 85°C water bath. Mix borneol acrylate and vinylthiazolidinedione and add them to the mixture. Then, add 0.22wt% KPS aqueous solution dropwise. After the addition is complete, continue the reaction at 85°C for 3 hours. Dialyze the resulting emulsion and freeze-dry it to obtain thiazolidinedione-borneol-based cationic nanospheres, which are antibacterial nanospheres. The ratio of methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, sodium dodecylbenzenesulfonate, deionized water, borneol acrylate, vinylthiazolidinedione, and KPS aqueous solution is 3mmol:2.25mmol:0.045g:45mL:4.5mmol:12mmol:30mL.

[0062] Example 3: Modified MXene was prepared by the following steps:

[0063] Step A1: Mix 4,6-dihydroxy-2-mercaptopyrimidine, 5wt% sodium hydroxide aqueous solution, and 1,4-dioxane, stir at 50°C for 30 min, then add 4-bromomethylbenzyl alcohol dropwise, stir at 50°C for 4 h, cool to room temperature, filter, wash, dry, and recrystallize to obtain the intermediate product. The molar ratio of 1,4,6-dihydroxy-2-mercaptopyrimidine, sodium hydroxide aqueous solution, 1,4-dioxane, and 4-bromomethylbenzyl alcohol is 0.39 mol: 320 mL: 700 mL: 0.4 mol.

[0064] Step A2: Mix intermediate product 1 and toluene, stir and heat to 80℃, add boron trifluoride-diethyl ether complex, and dropwise add 2,3-epoxypropyltrimethylammonium chloride solution. After the addition is complete, reflux for 3 hours, and distill under reduced pressure to obtain intermediate product 2. The ratio of intermediate product 1, toluene, boron trifluoride-diethyl ether complex and 2,3-epoxypropyltrimethylammonium chloride solution is 0.3mol:200mL:0.08g:150mL. The 2,3-epoxypropyltrimethylammonium chloride solution is prepared by mixing 2,3-epoxypropyltrimethylammonium chloride and anhydrous methanol at a ratio of 0.345mol:150mL.

[0065] Step A3: Mix lithium fluoride and 9 mol / L hydrochloric acid solution, stir for 20 min, then add Ti3AlC2, and etch in a 35℃ water bath for 48 h. Collect the mixture by centrifugation, add deionized water and shake well. Repeat centrifugation several times until the pH of the supernatant is greater than 6. Transfer the obtained precipitate to 100 mL of deionized water, sonicate in an ice-water bath under nitrogen protection for 1 h, and centrifuge for 1 h to obtain MXene suspension, which is intermediate product 3. The ratio of lithium fluoride, hydrochloric acid solution and Ti3AlC2 is 3 g: 50 mL: 3 g.

[0066] Step A4: Mix intermediate product 2 and 70wt% ethanol aqueous solution, add intermediate product 3, stir at 30℃ for 24h, then centrifuge and wash, vacuum dry to obtain modified MXene. The ratio of intermediate product 2, ethanol aqueous solution and intermediate product 3 is 0.003mol:60mL:20mL.

[0067] Antibacterial nanospheres are prepared by the following steps:

[0068] Step B1: Mix methacrylic acid and dichloromethane, then add EDCI and 4-dimethylaminopyridine, stir for 1 h, add dextrorotatory borneol, stir at room temperature for 6 h. After the reaction is complete, wash three times with 1 mol / L hydrochloric acid solution, saturated sodium bicarbonate solution, and saturated sodium chloride solution, then dry, filter, rotary evaporate, purify, rotary evaporate, and vacuum dry to obtain borneol acrylate. The ratio of methacrylic acid, dichloromethane, EDCI, 4-dimethylaminopyridine, dextrorotatory borneol, hydrochloric acid solution, saturated sodium bicarbonate solution, and saturated sodium chloride solution is 0.2 mol: 600 mL: 0.4 mol: 0.04 mol: 0.24 mol: 600 mL: 600 mL: 600 mL.

[0069] Step B2: Mix 4-vinylbenzaldehyde, thiazolidinedione, and anhydrous ethanol, stir, add hexahydropyridine and glacial acetic acid, reflux at 80°C for 24 h, precipitate the solid with water, filter and dry to obtain vinylthiazolidinedione. The molar ratio of 4-vinylbenzaldehyde, thiazolidinedione, anhydrous ethanol, hexahydropyridine, and glacial acetic acid is 0.2 mol: 0.38 mol: 300 mL: 0.01 mol: 0.01 mol.

[0070] Step B3: Mix methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, sodium dodecylbenzenesulfonate, and deionized water to obtain a mixture. Place the mixture in an 85°C water bath. Mix borneol acrylate and vinylthiazolidinedione and add them to the mixture. Then, add 0.22wt% KPS aqueous solution dropwise. After the addition is complete, continue the reaction at 85°C for 3 hours. Dialyze the resulting emulsion and freeze-dry it to obtain thiazolidinedione-borneol-based cationic nanospheres, which are antibacterial nanospheres. The ratio of methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, sodium dodecylbenzenesulfonate, deionized water, borneol acrylate, vinylthiazolidinedione, and KPS aqueous solution is 4mmol:3mmol:0.06g:60mL:6mmol:16mmol:40mL.

[0071] Example 4: A method for preparing a UV-curable anti-corrosion coating, comprising the following steps:

[0072] 45 parts epoxy acrylate resin, 1.5 parts modified MXene prepared in Example 1, 0.5 parts antibacterial nanospheres prepared in Example 1, 5 parts defoamer BYK-024, 0.1 parts leveling agent BYK-333, 0.1 parts curing agent Y-593, 4 parts photoinitiator 2959, and 20 parts deionized water;

[0073] Step S1: Weigh the raw materials according to the weight parts, add epoxy acrylate resin to the mixing tank, add defoamer BYK-024, leveling agent BYK-333 and curing agent Y-593 and stir, disperse at high speed for 30 minutes;

[0074] Step S2: After the raw materials in the mixing tank are stirred evenly and ground thoroughly, reduce the stirring speed, add the modified MXene prepared in Example 1 and the antibacterial nanospheres prepared in Example 1 according to the ratio and stir, gradually increase the stirring speed to disperse them evenly.

[0075] Step S3: Add photoinitiator 2959 and deionized water to the mixing tank in the mixing process according to the ratio, adjust the viscosity of the coating, and obtain the UV-curable anti-corrosion coating.

[0076] Example 5: A method for preparing a UV-curable anti-corrosion coating, comprising the following steps:

[0077] 55 parts epoxy acrylate resin, 2 parts modified MXene prepared in Example 2, 1 part antibacterial nanospheres prepared in Example 2, 7 parts defoamer SF-8091, 0.3 parts leveling agent BYK-346, 0.2 parts curing agent Y-3315, 5006 parts photoinitiator, and 23 parts deionized water;

[0078] Step S1: Weigh the raw materials according to the weight parts, add epoxy acrylate resin to the mixing tank, add defoamer SF-8091, leveling agent BYK-346 and curing agent Y-3315 and stir, disperse at high speed for 40 minutes;

[0079] Step S2: After the raw materials in the mixing tank are stirred evenly and ground thoroughly, reduce the stirring speed, add the modified MXene prepared in Example 2 and the antibacterial nanospheres prepared in Example 2 according to the ratio and stir, gradually increase the stirring speed to disperse them evenly;

[0080] Step S3: Add photoinitiator 500 and deionized water to the mixing tank in the mixing process according to the ratio, adjust the viscosity of the coating, and obtain the UV-curable anti-corrosion coating.

[0081] Example 6: A method for preparing a UV-curable anti-corrosion coating, comprising the following steps:

[0082] 65 parts epoxy acrylate resin, 3 parts modified MXene prepared in Example 3, 1.5 parts antibacterial nanospheres prepared in Example 3, 5 parts defoamer SF-8091, 5 parts defoamer XW6567, 0.2 parts leveling agent BYK-333, 0.3 parts leveling agent BYK-346, 0.1 parts curing agent Y-3318, 0.2 parts curing agent Y-1619, 4 parts photoinitiator 500, 4 parts photoinitiator 659, and 25 parts deionized water;

[0083] Step S1: Weigh the raw materials according to the weight parts, add epoxy acrylate resin to the mixing tank, add defoamer SF-8091, defoamer XW6567, leveling agent BYK-333, leveling agent BYK-346, curing agent Y-3318 and curing agent Y-1619 and stir, disperse at high speed for 50 minutes;

[0084] Step S2: After the raw materials in the mixing tank are stirred evenly and ground thoroughly, reduce the stirring speed, add the modified MXene prepared in Example 3 and the antibacterial nanospheres prepared in Example 3 according to the ratio and stir, gradually increase the stirring speed to disperse them evenly.

[0085] Step S3: Add photoinitiator 500, photoinitiator 659 and deionized water to the mixing tank in the mixing according to the ratio, adjust the viscosity of the coating, and obtain the UV-curable anti-corrosion coating.

[0086] Comparative Example 1: This comparative example is an anti-corrosion coating. The difference between this example and Example 6 is that silica is used instead of the modified MXene prepared in Example 3. All other aspects are the same.

[0087] Comparative Example 2: This comparative example is an anti-corrosion coating. The difference between this example and Example 6 is that zinc oxide is used instead of the antibacterial nanospheres prepared in Example 3. All other aspects are the same.

[0088] Comparative Example 3: This comparative example is an anti-corrosion coating. The difference between this example and Example 6 is that silica is used instead of the modified MXene prepared in Example 3, and zinc oxide is used instead of the antibacterial nanospheres prepared in Example 3. All other aspects are the same.

[0089] The coatings prepared in Examples 4-6 and Comparative Examples 1-3 were subjected to performance tests. Low-carbon steel was used as the substrate for testing. Before testing, the surface of the substrate was cleaned with acetone to remove organic matter and grease. A frame-type coating applicator was used to apply the coatings to the low-carbon steel. After leveling, the coatings were cured and cross-linked using a belt-type UV curing machine. The curing energy was 1000 mJ / cm2, the belt speed was 5.5 m / min, and the curing time was 50 ± 5 s. Then, the coatings were placed in a forced-air oven for heat curing at 70°C for 3 hours. The resulting dry film thickness was 60 ± 5 μm.

[0090] Performance testing:

[0091] Impact resistance test: Tested according to GB / T 1732-2020;

[0092] Media resistance test: The acid resistance, alkali resistance and salt water resistance of the coating were tested according to GB / T 9274-1988 "Determination of resistance to liquid media for paints and varnishes". The corrosive media were 5wt% H2SO4 solution, 5wt% NaOH solution and 3wt% NaCl solution. The sample was placed horizontally with the coating side facing up. Several drops of corrosive media were added, with a minimum 20mm interval between the centers of adjacent liquids. The sample was placed at (23±2℃) for 90 days to allow it to fully contact the air, but without any other interference. After that, the coating surface was thoroughly washed with clean water and the coating was immediately (1min) checked for any changes. If there were no changes on the coating surface and no whitening, blistering, corrosion or peeling occurred, the coating was considered to have passed the media resistance test.

[0093] Salt spray resistance: Its salt spray resistance was tested according to GB / T 1771-2007;

[0094] Corrosion resistance: Tested according to GB / T 6461-2002;

[0095] Antibacterial rate: tested according to GB / T 21866-2008.

[0096] The test results are shown in Table 1:

[0097] Table 1: Performance Test Results

[0098]

[0099] As shown in Table 1, the UV-curable anti-corrosion coating prepared by this invention has an impact resistance of over 49 kg·cm and a corrosion test grade of 10. Examples 6 and Comparative Example 1 show that the modified MXene prepared by this invention improves the corrosion resistance of the coating, while Examples 6 and Comparative Example 2 show that the nano-antibacterial microspheres prepared by this invention improve the antibacterial rate of the coating. This demonstrates that the UV-curable anti-corrosion coating prepared by this invention possesses excellent anti-corrosion and antibacterial properties.

[0100] The above content is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the scope defined by the inventive concept, they should all fall within the protection scope of the present invention.

Claims

1. A UV-cured anticorrosive coating, characterized by, The raw materials include the following parts by weight: 45-65 parts epoxy acrylate resin, 1.5-3 parts modified MXene, 0.5-1.5 parts antibacterial nanospheres, 5-10 parts defoamer, 0.1-0.5 parts leveling agent, 0-0.3 parts curing agent, 4-8 parts photoinitiator, and 20-25 parts deionized water; The modified MXene is prepared by the following steps: Step A1: Mix 4,6-dihydroxy-2-mercaptopyrimidine, 5wt% sodium hydroxide aqueous solution and 1,4-dioxane, stir at 50°C for 30 min, then add 4-bromomethylbenzyl alcohol dropwise, stir at 50°C for 4 h, cool to room temperature, filter, wash, dry and recrystallize to obtain intermediate product 1; Step A2: Mix intermediate product 1 with toluene, stir and heat to 80°C, add boron trifluoride-diethyl ether complex, add 2,3-epoxypropyltrimethylammonium chloride solution dropwise, after the addition is complete, reflux for 3 hours, and distill under reduced pressure to obtain intermediate product 2. Step A3: Mix lithium fluoride and 9 mol / L hydrochloric acid solution, stir for 20 min, then add Ti3AlC2, and etch in a 35℃ water bath for 48 h. Collect the mixture by centrifugation, add deionized water and shake well. Repeat centrifugation several times until the pH of the supernatant is greater than 6. Transfer the obtained precipitate to 100 mL of deionized water, sonicate in an ice-water bath under nitrogen protection for 1 h, and centrifuge for 1 h to obtain MXene suspension, which is intermediate product 3. Step A4: Mix intermediate product 2 with 70wt% ethanol aqueous solution, add intermediate product 3, stir at 30℃ for 24h, then centrifuge and wash, and vacuum dry to obtain modified MXene.

2. The UV-cured anticorrosive paint according to claim 1, characterized in that, In step A1, the ratio of the amounts of 4,6-dihydroxy-2-mercaptopyrimidine, sodium hydroxide aqueous solution, 1,4-dioxane, and 4-bromomethylbenzyl alcohol is 0.19-0.39 mol: 160-320 mL: 400-700 mL: 0.2-0.4 mol.

3. The UV-cured anticorrosive paint according to claim 1, characterized in that, In step A2, the ratio of intermediate product 1, toluene, boron trifluoride-diethyl ether complex, and 2,3-epoxypropyltrimethylammonium chloride solution is 0.1-0.3 mol: 150-200 mL: 0.02-0.08 g: 100-150 mL. The 2,3-epoxypropyltrimethylammonium chloride solution is prepared by mixing 2,3-epoxypropyltrimethylammonium chloride and anhydrous methanol at a ratio of 0.115-0.345 mol: 50-150 mL.

4. The UV-cured anticorrosive coating according to claim 1, characterized in that, In step A3, the ratio of lithium fluoride, hydrochloric acid solution, and Ti3AlC2 is 2-3g: 40-50mL: 2-3g.

5. The UV-curable anti-corrosion coating according to claim 1, characterized in that, In step A4, the ratio of intermediate product 2, ethanol aqueous solution and intermediate product 3 is 0.001-0.003 mol: 20-60 mL: 20 mL.

6. The UV-curable anti-corrosion coating according to claim 1, characterized in that, The antibacterial nanospheres are prepared by the following steps: Step B1: Mix methacrylic acid and dichloromethane, then add EDCI and 4-dimethylaminopyridine, stir for 1 h, add dextrorotatory borneol, stir at room temperature for 6 h. After the reaction is complete, wash three times with 1 mol / L hydrochloric acid solution, saturated sodium bicarbonate solution and saturated sodium chloride solution, then dry, filter, rotary evaporate, purify, rotary evaporate and vacuum dry to obtain borneol acrylate. Step B2: Mix 4-vinylbenzaldehyde, thiazolidinedione and anhydrous ethanol, stir, add hexahydropyridine and glacial acetic acid, reflux at 80°C for 24 h, precipitate the solid with water, filter and dry to obtain vinylthiazolidinedione. Step B3: Mix methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, sodium dodecylbenzenesulfonate, and deionized water to obtain a mixture. Place the mixture in an 85°C water bath. Mix borneol acrylate and vinylthiazolidinedione and add them to the mixture. Then, add 0.22wt% KPS aqueous solution dropwise. After the addition is complete, continue the reaction at 85°C for 3 hours. Dialyze the resulting emulsion and freeze-dry it to obtain thiazolidinedione-borneol-based cationic nanospheres, which are antibacterial nanospheres.

7. The UV-curable anti-corrosion coating according to claim 6, characterized in that, In step B1, the ratio of the amounts of methacrylic acid, dichloromethane, EDCI, 4-dimethylaminopyridine, dextrorotatory borneol, hydrochloric acid solution, saturated sodium bicarbonate solution, and saturated sodium chloride solution is 0.1-0.2 mol: 400-600 mL: 0.2-0.4 mol: 0.02-0.04 mol: 0.12-0.24 mol: 600 mL: 600 mL: 600 mL.

8. The UV-curable anti-corrosion coating according to claim 6, characterized in that, In step B2, the ratio of 4-vinylbenzaldehyde, thiazolidinedione, anhydrous ethanol, hexahydropyridine, and glacial acetic acid is 0.1-0.2 mol: 0.19-0.38 mol: 200-300 mL: 0.005-0.01 mol: 0.005-0.01 mol.

9. The UV-curable anti-corrosion coating according to claim 6, characterized in that, In step B3, the ratio of the amounts of methacryloyloxyethyltrimethylammonium chloride, N,N'-methylenebisacrylamide, sodium dodecylbenzenesulfonate, deionized water, bornyl acrylate, vinylthiazolidinedione, and KPS aqueous solution is 2-4 mmol: 1.5-3 mmol: 0.03-0.06 g: 30-60 mL: 3-6 mmol: 8-16 mmol: 20-40 mL.

10. A method for preparing the UV-curable anti-corrosion coating according to any one of claims 1-9, characterized in that, The UV-curable anti-corrosion coating is prepared by the following steps: Step S1: Weigh the raw materials according to the weight parts, add epoxy acrylate resin to the mixing tank, add defoamer, leveling agent and curing agent and stir, disperse at high speed for 30-50 minutes; Step S2: After the raw materials in the mixing tank are stirred evenly and ground thoroughly, reduce the stirring speed, add modified MXene and antibacterial nanospheres according to the ratio and stir, gradually increase the stirring speed to disperse them evenly; Step S3: Add photoinitiator and deionized water to the mixing tank in the mixing process according to the ratio, adjust the viscosity of the coating, and obtain UV-curable anti-corrosion coating.

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