An antibacterial coating and a method for preparing the same

Abstract

The application discloses an antibacterial coating and a preparation method thereof. The antibacterial coating comprises the following raw materials in parts by weight: 0.3-1 parts of modified nano zinc oxide, 10-20 parts of ethanol, 80-90 parts of pentaerythritol triacrylate, 5-10 parts of modified isocyanate, 0.1-0.5 parts of N-ethyl morpholine, 1-5 parts of a photosensitive initiator and 1-10 parts of an adhesion promoter. The antibacterial ability of the nano zinc oxide is strengthened by modification, and the nano zinc oxide is not prone to polymerization in the oily coating, so that the good antibacterial ability of the nano zinc oxide is exerted. The isocyanate is modified to have an antibacterial group, and the antibacterial group guanidino is introduced on the polyurethane long chain, so that the good antibacterial effect is achieved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of coatings, and particularly relates to an antibacterial coating and a preparation method thereof. BACKGROUND

[0002] With the development of science and technology, people are increasingly aware of the threat of bacterial and viral infections to the human body. In life, coatings are widely used on furniture and vehicles that people contact daily, so the development of a high-efficiency antibacterial coating has a positive significance for preventing the spread of bacteria and viruses.

[0003] Antibacterial is generally divided into active antibacterial and passive antibacterial. Active antibacterial generally adds an antibacterial agent to the coating, and the antibacterial agent is divided into natural, inorganic and organic antibacterial agents. Passive antibacterial, such as forming a super-hydrophobic or super-hydrophilic coating, reduces the adhesion of bacteria to achieve antibacterial effect.

[0004] Natural antibacterial agents such as sorbic acid (2,4-hexadienoic acid) are environmentally friendly, harmless to the human body, and non-irritating, but they are greatly affected by factors such as temperature and pH, and have poor applicability in industry. Inorganic antibacterial agents are usually a type of antibacterial agent that uses silver, copper, titanium, zinc and other metals as antibacterial substances. According to the antibacterial mechanism, they are divided into two categories: photocatalytic and metal. Photocatalytic inorganic antibacterial agents include TiO2, ZnO, SiC, etc. Metal type antibacterial agents are porous materials loaded with Ag + , Cu 2+ , Zn 2+ ions and Ag, Cu, Zn and their oxides. Inorganic antibacterial agents generally have good thermal stability, low toxicity, and are easy to process. Their antibacterial performance has the advantages of broad-spectrum, slow release, long-acting, etc. Organic antibacterial agents include acylanilines, quaternary ammonium salts, pyridines, phenols, biguanides, alcohols, etc. The advantages of organic antibacterial agents are low cost, fast-acting and strong antibacterial effect. Among inorganic antibacterial agents, nano-zinc oxide has lower cost than Ag-based antibacterial agents, and does not produce toxic Cu 2+ compared to Cu-based antibacterial agents. At the same time, compared to Ti-based antibacterial agents, nano-zinc oxide can only produce antibacterial effect under light conditions. Nano-zinc oxide has both photocatalytic and metal antibacterial mechanisms, and is suitable for various situations. It is an ideal antibacterial agent for coatings. However, the antibacterial performance of nano-zinc oxide is poorer than that of Ag and Cu-based antibacterial agents, and the antibacterial effect needs to be improved. Nano-zinc oxide is hydrophilic and can easily polymerize in oil-based coatings, which cannot effectively play an antibacterial role.

[0005] Isocyanate is added to pentaerythritol triacrylate to react with the hydroxyl groups on pentaerythritol triacrylate, thereby improving the overall adhesion, heat resistance and hardness of the coating layer. However, it does not have antibacterial ability. SUMMARY

[0006] In order to solve the above problems, the present application provides an antibacterial coating and a preparation method thereof.

[0007] The object of the present application can be achieved by the following technical solutions:

[0008] An antibacterial coating comprises the following components:

[0009] 0.3-1 parts of modified nano zinc oxide, 10-20 parts of ethanol, 80-90 parts of pentaerythritol triacrylate, 5-10 parts of modified isocyanate, 0.1-0.5 parts of N-ethyl morpholine, 1-5 parts of a photosensitive initiator, and 1-10 parts of a tackifier;

[0010] An antibacterial coating is prepared by the following steps:

[0011] S1: Modified nano zinc oxide is added to ethanol, stirred at 200-300 rpm and ultrasonically dispersed for 20 min to obtain a suspension for standby use;

[0012] S2: Pentaerythritol triacrylate, modified isocyanate and N-ethyl morpholine are added to a reaction container, heated to 70-80°C, and stirred at 200-300 rpm for 30-40 min to obtain a mixed solution;

[0013] S3: The suspension, photosensitive initiator and tackifier are slowly added to the mixed solution, heated to 70-80°C, and stirred at 200-300 rpm for 3-4 h, and the desired antibacterial coating is obtained after cooling.

[0014] The modified nano zinc oxide is prepared by the following method:

[0015] Nano zinc oxide is put into anhydrous ethanol, magnetically stirred for 10 min and ultrasonically dispersed for 20 min to obtain a nano zinc oxide dispersion liquid, the stirring rate is 100-150 rpm, a modified silane coupling agent is added to the nano zinc oxide dispersion liquid, heated to 75-78°C in a water bath for 1-1.5 h, then the dispersion liquid is centrifuged to obtain a precipitate, and the obtained precipitate is vacuum dried at 50°C for 12 h to obtain modified nano zinc oxide, the dosage ratio of nano zinc oxide, anhydrous ethanol and modified coupling agent is 0.5-1 kg: 8-9 kg: 0.05-0.1 kg;

[0016] The modified silane coupling agent has two different groups on both sides of silicon as the center, which can connect inorganic and organic matrices, the inorganic group combines with the surface functional groups of zinc oxide to form stable chemical bonds, and the organic group with antibacterial and hydrophobic effects is combined with zinc oxide to modify zinc oxide, improve its antibacterial performance and hydrophobic ability, and make it not easy to polymerize in oily coatings.

[0017] Further, the modified silane coupling agent is synthesized by the following steps:

[0018] A1: 1-(3-hydroxypropyl)-1,3,5-triazine-2,4,6-trione is added into carbon tetrachloride, stirred at 200-300 rpm and heated to 30-40°C, then thionyl chloride is added, reacted for 1-2 h, then 1% sodium hypochlorite solution by mass fraction is added, reacted for 1-2 h, and then vacuum dried at 60°C to obtain intermediate a, 1-(3-hydroxypropyl)-1,3,5-triazine-2,4,6-trione, carbon tetrachloride, thionyl chloride and sodium hypochlorite solution in a ratio of 1 mol: 10-15 mol: 1-1.5 mol: 15-20 kg;

[0019] During the reaction, 1-(3-hydroxypropyl)-1,3,5-triazine-2,4,6-trione reacts with thionyl chloride in a one-to-one ratio, and the chlorine in thionyl chloride replaces the hydroxyl group in 1-(3-hydroxypropyl)-1,3,5-triazine-2,4,6-trione, and then sodium hypochlorite solution is added to halogenate it to obtain intermediate a, wherein the N-haloamine group has good antibacterial hydrophobic properties, and the specific structure is as follows:

[0020]

[0021] A2: Intermediate a and (N,N-dimethyl-3-aminopropyl)trimethoxysilane are added into n-butanol, stirred at 200-300 rpm, and reacted under the conditions of microwave power 600 W and temperature 130°C for 3-4 h, then rotary evaporated under reduced pressure, and then vacuum dried at 50°C for 12 h to obtain a modified silane coupling agent, intermediate a, (N,N-dimethyl-3-aminopropyl)trimethoxysilane and n-butanol in a ratio of 1 mol: 1 mol: 2-3 mol.

[0022] During the reaction, intermediate a reacts with (N,N-dimethyl-3-aminopropyl)trimethoxysilane in a one-to-one ratio, and in the microwave reactor, the chloropropyl group of intermediate a combines with the N,N-dimethyl-3-aminopropyl group at the end of (N,N-dimethyl-3-aminopropyl)trimethoxysilane to form a quaternary ammonium salt structure with good antibacterial effect.

[0023]

[0024] Further, the modified isocyanate is made by the following method:

[0025] B1: N,N-di-BOC-S-methyl isothiourea is added into dichloromethane, stirring at 150-200 rpm and adding ethanolamine, and reacting at a temperature of 25-30 DEG C for 18-24 h, and then cooling and filtering to obtain a guanidyl intermediate, wherein the amount ratio of N,N-di-BOC-S-methyl isothiourea, dichloromethane and ethanolamine is 1 mol: 5-10 mol: 1-1.2 mol;

[0026] During the reaction, N,N-di-BOC-S-methyl isothiourea and ethanolamine undergo a nucleophilic substitution reaction to generate a guanidyl group, and the guanidyl group has a good antibacterial effect and simultaneously introduces a hydroxyl group, and the specific structure is as follows:

[0027]

[0028] B2: 1,3,5-triisocyanate phenyl is added into dichloromethane, stirring at 150-200 rpm and adding stannous octoate and a guanidyl intermediate, and reacting at a temperature of 35-40 DEG C for 12-14 h, and then vacuum rotary evaporation and filtering, and washing the precipitated solid with petroleum ether 5 times to obtain a modified isocyanate, wherein the amount ratio of 1,3,5-triisocyanate phenyl, dichloromethane, stannous octoate and the guanidyl intermediate is 1 mol: 5-10 mol: 0.3-0.5 mol: 1-1.3 mol.

[0029] During the reaction, the isocyanate group of 1,3,5-triisocyanate phenyl and the hydroxyl group of the guanidyl intermediate undergo an addition reaction to obtain a modified isocyanate.

[0030]

[0031] The photosensitive initiator is at least one of 2-methyl-2-(4-morpholinyl)-1-[4-(methylthio)phenyl]-1-propanone, methyl benzoylformate or 2-dimethylamino-2-benzyl-1-4-(4-morpholinyl)phenyl]-1-butanone.

[0032] The tackifier is at least one of ketone aldehyde resin, xylene aldehyde resin or carbon five petroleum resin.

[0033] The present application has the following beneficial effects:

[0034] This invention prepares an antibacterial coating in which the antibacterial effect of nano-zinc oxide is weaker than that of conventional antibacterial agents. The antibacterial ability is enhanced by combining nano-zinc oxide with a modified silane coupling agent. Simultaneously, the organic groups on the coupling agent prevent polymerization in oil-based coatings, allowing the nano-zinc oxide to exert its excellent antibacterial properties. The modified silane coupling agent is based on (N,N-dimethyl-3-aminopropyl)trimethoxysilane, which reacts with intermediate a in a microwave reactor to generate quaternary ammonium groups, while simultaneously introducing N-haloamine groups. Both the quaternary ammonium groups and the N-haloamine groups possess excellent active antibacterial capabilities. It also possesses a certain degree of hydrophobicity, reducing bacterial adhesion and forming a passive antibacterial effect. Isocyanates typically do not have antibacterial groups when used in coatings. Modifying isocyanates to give them antibacterial groups involves a nucleophilic substitution reaction between N,N-di-BOC-S-methylisothiourea and ethanolamine to generate guanidine groups. Simultaneously, the introduced hydroxyl groups react with 1,3,5-phenyl triisocyanate in a 1:1 ratio to obtain modified isocyanates. The modified isocyanates are then polymerized with pentaerythritol triacrylate under the action of a catalyst, introducing the antibacterial guanidine group onto the long polyurethane chain, resulting in good antibacterial effects. Detailed Implementation

[0035] 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. Example 1

[0036] A modified nano zinc oxide is prepared by the following steps:

[0037] Nano zinc oxide was added to anhydrous ethanol, magnetically stirred for 10 min and ultrasonically dispersed for 20 min to obtain a nano zinc oxide dispersion. The stirring speed was 130 rpm. A modified silane coupling agent was added to the nano zinc oxide dispersion, and the mixture was heated in a water bath to 78°C for 1.5 h. The dispersion was then centrifuged to obtain a precipitate, which was then vacuum dried at 50°C for 12 h to obtain modified nano zinc oxide. The ratio of nano zinc oxide, anhydrous ethanol and modified coupling agent was 0.5 kg: 8 kg: 0.05 kg.

[0038] The modified coupling agent is prepared by the following steps:

[0039] The 1-(3-hydroxypropyl) 1,3,5-triazine-2,4,6-trione is added into carbon tetrachloride, stirred at 200 rpm and heated to 30°C, then the thionyl chloride is added, reacted for 2 h, then the 1% sodium hypochlorite solution by mass percentage is added, reacted for 2 h, and then dried at 60°C under vacuum to obtain the intermediate a, the amount ratio of 1-(3-hydroxypropyl) 1,3,5-triazine-2,4,6-trione, carbon tetrachloride, thionyl chloride and sodium hypochlorite solution is 1 mol: 10 mol: 1 mol: 15 kg;

[0040] The intermediate a and (N,N-dimethyl-3-aminopropyl) trimethoxysilane are added into n-butanol, stirred at 200 rpm, and reacted for 4 h under the conditions of microwave power 600 W and temperature 130°C, then rotary evaporated under reduced pressure, and then dried at 50°C under vacuum for 12 h to obtain the modified silane coupling agent, the amount ratio of intermediate a, (N,N-dimethyl-3-aminopropyl) trimethoxysilane and n-butanol is 1 mol: 1 mol: 2 mol. Example 2

[0041] A modified nano zinc oxide is prepared by the following steps:

[0042] The nano zinc oxide is added into anhydrous ethanol, magnetically stirred for 10 min and ultrasonically dispersed for 20 min to obtain a nano zinc oxide dispersion liquid, the stirring rate is 150 rpm, the modified silane coupling agent is added into the nano zinc oxide dispersion liquid, heated to 75°C in a water bath and reacted for 1.5 h, then the dispersion liquid is centrifuged to obtain a precipitate, and then the obtained precipitate is dried at 50°C under vacuum for 12 h to obtain the modified nano zinc oxide, the amount ratio of nano zinc oxide, anhydrous ethanol and modified coupling agent is 1 kg: 9 kg: 0.1 kg;

[0043] The modified coupling agent is prepared by the following steps:

[0044] The 1-(3-hydroxypropyl) 1,3,5-triazine-2,4,6-trione is added into carbon tetrachloride, stirred at 300 rpm and heated to 40°C, then the thionyl chloride is added, reacted for 1 h, then the 1% sodium hypochlorite solution by mass percentage is added, reacted for 1 h, and then dried at 60°C under vacuum to obtain the intermediate a, the amount ratio of 1-(3-hydroxypropyl) 1,3,5-triazine-2,4,6-trione, carbon tetrachloride, thionyl chloride and sodium hypochlorite solution is 1 mol: 15 mol: 1.5 mol: 20 kg;

[0045] The intermediate a and (N,N-dimethyl-3-aminopropyl)trimethoxysilane were added into n-butanol, stirred at 300 rpm, and reacted under the conditions of microwave power 600 W and temperature 130 °C for 3 h, followed by rotary evaporation under reduced pressure, and vacuum drying at 50 °C for 12 h to obtain the modified silane coupling agent, the dosage ratio of intermediate a, (N,N-dimethyl-3-aminopropyl)trimethoxysilane and n-butanol being 1 mol:1 mol:3 mol. Example 3

[0046] A modified nano zinc oxide was prepared by the following steps:

[0047] The nano zinc oxide was added into anhydrous ethanol, magnetically stirred for 10 min and ultrasonically dispersed for 20 min to obtain a nano zinc oxide dispersion liquid, the stirring rate being 100 rpm, the modified silane coupling agent was added into the nano zinc oxide dispersion liquid, heated in a water bath to 77 °C and reacted for 1.3 h, followed by centrifugation of the dispersion liquid to obtain a precipitate, and vacuum drying of the obtained precipitate at 50 °C for 12 h to obtain the modified nano zinc oxide, the dosage ratio of nano zinc oxide, anhydrous ethanol and modified coupling agent being 0.8 kg:8.5 kg:0.08 kg;

[0048] The modified coupling agent was prepared by the following steps:

[0049] 1-(3-hydroxypropyl)-1,3,5-triazine-2,4,6-trione was added into carbon tetrachloride, stirred at 250 rpm and heated to 35 °C, followed by addition of sulfur chloride, reaction for 1.5 h, addition of a 1% sodium hypochlorite solution in mass percentage, and reaction for another 1.5 h, followed by vacuum drying at 60 °C to obtain intermediate a, the dosage ratio of 1-(3-hydroxypropyl)-1,3,5-triazine-2,4,6-trione, carbon tetrachloride, sulfur chloride and sodium hypochlorite solution being 1 mol:13 mol:1.3 mol:18 kg;

[0050] The intermediate a and (N,N-dimethyl-3-aminopropyl)trimethoxysilane were added into n-butanol, stirred at 250 rpm, and reacted under the conditions of microwave power 600 W and temperature 130 °C for 3.5 h, followed by rotary evaporation under reduced pressure, and vacuum drying at 50 °C for 12 h to obtain the modified silane coupling agent, the dosage ratio of intermediate a, (N,N-dimethyl-3-aminopropyl)trimethoxysilane and n-butanol being 1 mol:1 mol:2.5 mol. Example 4

[0051] A modified isocyanate was prepared by the following steps:

[0052] N,N-di-BOC-S-methyl isothiourea was added to dichloromethane, stirred at 150 rpm and ethanolamine was added and reacted for 24 h at a temperature of 25 °C, cooled and filtered to obtain the guanidino intermediate, N,N-di-BOC-S-methyl isothiourea, dichloromethane and ethanolamine in a ratio of 1 mol: 5 mol: 1 mol;

[0053] 1,3,5-triisocyanate phenyl was added to dichloromethane, stirred at 150 rpm and stannous octoate and guanidino intermediate were added and reacted for 14 h at a temperature of 35 °C, vacuum evaporated and filtered, the solid that separated was washed with petroleum ether 5 times to obtain the modified isocyanate, 1,3,5-triisocyanate phenyl, dichloromethane, stannous octoate and guanidino intermediate in a ratio of 1 mol: 5 mol: 0.3 mol: 1 mol. Example 5

[0054] A modified isocyanate was prepared by the following steps:

[0055] N,N-di-BOC-S-methyl isothiourea was added to dichloromethane, stirred at 200 rpm and ethanolamine was added and reacted for 18 h at a temperature of 30 °C, cooled and filtered to obtain the guanidino intermediate, N,N-di-BOC-S-methyl isothiourea, dichloromethane and ethanolamine in a ratio of 1 mol: 10 mol: 1.2 mol;

[0056] 1,3,5-triisocyanate phenyl was added to dichloromethane, stirred at 200 rpm and stannous octoate and guanidino intermediate were added and reacted for 12 h at a temperature of 40 °C, vacuum evaporated and filtered, the solid that separated was washed with petroleum ether 5 times to obtain the modified isocyanate, 1,3,5-triisocyanate phenyl, dichloromethane, stannous octoate and guanidino intermediate in a ratio of 1 mol: 10 mol: 0.3-0.5 mol: 1.3 mol. Example 6

[0057] A modified isocyanate was prepared by the following steps:

[0058] N,N-di-BOC-S-methyl isothiourea was added to dichloromethane, stirred at 180 rpm and ethanolamine was added and reacted for 22 h at a temperature of 28 °C, cooled and filtered to obtain the guanidino intermediate, N,N-di-BOC-S-methyl isothiourea, dichloromethane and ethanolamine in a ratio of 1 mol: 8 mol: 1.1 mol;

[0059] The 1,3,5-triisocyanate phenyl was added into dichloromethane, stirred at 180 rpm and added stannous octoate and guanidino intermediate, reacted at 38℃ for 13 h, vacuum rotary evaporation and filtration, the precipitated solid was washed with petroleum ether for 5 times, to obtain the modified isocyanate, the amount ratio of 1,3,5-triisocyanate phenyl, dichloromethane, stannous octoate and guanidino intermediate was 1 mol:8 mol:0.3-0.5 mol:1.2 mol. Example 7

[0060] An antibacterial coating, comprising the following components:

[0061] 0.3 parts of the modified nano zinc oxide obtained in Experimental Example 1, 10 parts of ethanol, 80 parts of pentaerythritol triacrylate, 5 parts of the modified isocyanate obtained in Experimental Example 4, 0.1 parts of N-ethyl morpholine, 1 part of a photosensitive initiator and 1 part of an adhesion promoter;

[0062] An antibacterial coating, prepared by the following steps:

[0063] S1: The modified nano zinc oxide was added into ethanol, stirred at 200 rpm and ultrasonically dispersed for 20 min to obtain a suspension for standby use;

[0064] S2: The pentaerythritol triacrylate, the modified isocyanate and the N-ethyl morpholine were added into a reaction container, heated to 70℃, stirred at 200 rpm for 40 min to obtain a mixture;

[0065] S3: The suspension, the photosensitive initiator and the adhesion promoter were slowly added into the mixture, heated to 70℃, stirred at 200 rpm for 4 h, and the desired antibacterial coating was obtained after cooling. Example 8

[0066] An antibacterial coating, comprising the following components:

[0067] 1 part of the modified nano zinc oxide obtained in Experimental Example 1, 20 parts of ethanol, 90 parts of pentaerythritol triacrylate, 10 parts of the modified isocyanate obtained in Experimental Example 4, 0.5 parts of N-ethyl morpholine, 5 parts of a photosensitive initiator and 10 parts of an adhesion promoter;

[0068] An antibacterial coating, prepared by the following steps:

[0069] S1: The modified nano zinc oxide was added into ethanol, stirred at 300 rpm and ultrasonically dispersed for 20 min to obtain a suspension for standby use;

[0070] S2: The pentaerythritol triacrylate, the modified isocyanate and the N-ethyl morpholine were added into a reaction container, heated to 80℃, stirred at 300 rpm for 30 min to obtain a mixture;

[0071] S3: slowly add the suspension, the photosensitive initiator and the tackifier into the mixture, heat to 80℃, stir at 300rpm for 3h, and the desired antibacterial coating can be obtained after cooling. Example 9

[0072] An antibacterial coating, comprising the following components:

[0073] 0.6 parts of the modified nano zinc oxide obtained in Experimental Example 1, 15 parts of ethanol, 85 parts of pentaerythritol triacrylate, 8 parts of the modified isocyanate obtained in Experimental Example 4, 0.3 parts of N-ethyl morpholine, 3 parts of a photosensitive initiator and 6 parts of a tackifier;

[0074] An antibacterial coating, prepared by the following steps:

[0075] S1: add the modified nano zinc oxide into ethanol, stir at 260rpm and ultrasonic dispersion for 20min to obtain a suspension for standby;

[0076] S2: add pentaerythritol triacrylate, modified isocyanate and N-ethyl morpholine into a reaction container, heat to 75℃, stir at 260rpm for 35min to obtain a mixture;

[0077] S3: slowly add the suspension, the photosensitive initiator and the tackifier into the mixture, heat to 75℃, stir at 260rpm for 3.5h, and the desired antibacterial coating can be obtained after cooling.

[0078] Comparative Example 1

[0079] The comparative example is a commercially available antibacterial coating.

[0080] Comparative Example 2

[0081] Compared with Example 9, the modified nano zinc oxide is replaced by commercially available nano zinc oxide, and other steps are exactly the same as Example 9 to prepare an antibacterial coating.

[0082] Comparative Example 3

[0083] Compared with Example 9, the modified isocyanate is replaced by commercially available toluene diisocyanate, and other steps are exactly the same as Example 9 to prepare an antibacterial coating.

[0084] The antibacterial coating prepared by the present application is further detected for effect, and the detection results are shown in the following table:

[0085]

[0086] From the detection results of the table, it can be seen that the basic properties of hardness, impact strength, flexibility, hiding power, adhesion, tensile strength, water resistance and alcohol resistance of Example 7, Example 8 and Example 9 have no great difference compared with Comparative Example 1, and can meet the basic use requirements of the coating; the antibacterial efficiency and antibacterial durability of Example 7, Example 8 and Example 9 are improved compared with Comparative Example 1; it can be seen from Example 9 compared with Comparative Example 2 and Comparative Example 3 that under the combined action of modified nano zinc oxide and modified isocyanate, the antibacterial durability is greatly improved.

[0087] The above is only an example and description of the concept of the present application. Those skilled in the art can make various modifications or supplements to the described specific embodiments or use similar ways to replace them, as long as they do not deviate from the concept of the present application or exceed the scope defined by the present claims, which shall belong to the protection scope of the present application.

Claims

1. An antibacterial coating, characterized in that, Including the following parts by weight of raw materials: 0.3-1 parts modified nano zinc oxide, 10-20 parts ethanol, 80-90 parts pentaerythritol triacrylate, 5-10 parts modified isocyanate, 0.1-0.5 parts N-ethylmorpholine, 1-5 parts photosensitizer and 1-10 parts tackifier; The modified nano zinc oxide is prepared by the following steps: Nano zinc oxide was added to anhydrous ethanol, magnetically stirred for 10 min and ultrasonically dispersed for 20 min to obtain a nano zinc oxide dispersion. The stirring speed was 100-150 rpm. A modified silane coupling agent was added to the nano zinc oxide dispersion, and the mixture was heated in a water bath to 75-78℃ for 1-1.5 h. The dispersion was then centrifuged to obtain a precipitate, which was then vacuum dried at 50℃ for 12 h to obtain modified nano zinc oxide. The ratio of nano zinc oxide, anhydrous ethanol and modified coupling agent was 0.5-1 kg: 8-9 kg: 0.05-0.1 kg. The modified silane coupling agent is prepared by the following steps: A1: 1-(3-hydroxypropyl)1,3,5-triazine-2,4,6-trione was added to carbon tetrachloride, stirred at 200-300 rpm and heated to 30-40°C, then thionyl chloride was added and reacted for 1-2 h. Sodium hypochlorite solution was then added and reacted for 1-2 h. After that, the mixture was dried under vacuum at 60°C to obtain intermediate a. A2: Intermediate a and (N,N-dimethyl-3-aminopropyl)trimethoxysilane were added to n-butanol, stirred at 200-300 rpm, and reacted at microwave power of 600W and temperature of 130℃ for 3-4 hours. Then, the mixture was rotary evaporated under reduced pressure and dried under vacuum at 50℃ for 12 hours to obtain the modified silane coupling agent. The modified isocyanate is prepared by the following steps: B1: N,N-di-BOC-S-methylisothiourea was added to dichloromethane, stirred at 150-200 rpm and ethanolamine was added. The mixture was reacted at 25-30℃ for 18-24 h, cooled and filtered to obtain the guanidine intermediate. B2: Add 1,3,5-phenyl triisocyanate to dichloromethane, stir at 150-200 rpm and add stannous octoate and guanidine intermediate, react at 35-40℃ for 12-14 h, vacuum rotary evaporate and filter, wash the precipitated solid 5 times with petroleum ether to obtain modified isocyanate.

2. The antibacterial coating according to claim 1, characterized in that: In step A1, the ratio of 1-(3-hydroxypropyl)1,3,5-triazine-2,4,6-trione, carbon tetrachloride, thionyl chloride, and sodium hypochlorite solution is 1 mol: 10-15 mol: 1-1.5 mol: 15-20 kg, and the mass percentage concentration of sodium hypochlorite solution is 1%.

3. The antibacterial coating according to claim 1, characterized in that: In step A2, the ratio of intermediate a, (N,N-dimethyl-3-aminopropyl)trimethoxysilane to n-butanol is 1 mol: 1 mol: 2-3 mol.

4. The antibacterial coating according to claim 1, characterized in that: In step B1, the ratio of N,N-di-BOC-S-methylisothiourea, dichloromethane, and ethanolamine is 1 mol: 5-10 mol: 1-1.2 mol.

5. The antibacterial coating according to claim 1, characterized in that: In step B2, the ratio of phenyl 1,3,5-triisocyanate, dichloromethane, stannous octoate, and guanidinyl intermediate is 1 mol: 5-10 mol: 0.3-0.5 mol: 1-1.3 mol.

6. The antibacterial coating according to claim 1, characterized in that: The photoinitiator is at least one of 2-methyl-2-(4-morpholino)-1-[4-(methylthio)phenyl]-1-propanone, methyl benzoylcarbamate, or 2-dimethylamino-2-benzyl-1-4-(4-morpholino)phenyl]-1-butanone.

7. The antibacterial coating according to claim 1, characterized in that: The tackifier is at least one of ketone-aldehyde resin, xylene-formaldehyde resin, or C5 petroleum resin.

8. The method for preparing an antibacterial coating according to claim 1, characterized in that, Includes the following steps: S1: Add the modified nano zinc oxide to ethanol, stir at 200-300 rpm and ultrasonically disperse for 20 min to obtain a suspension for later use; S2: Add pentaerythritol triacrylate, modified isocyanate and N-ethylmorpholine to the reaction vessel, heat to 70-80℃, and stir at 200-300 rpm for 30-40 min to obtain a mixture; S3: Slowly add the suspension, photoinitiator and thickener to the mixture, heat to 70-80℃, stir at 200-300 rpm for 3-4 hours, and after cooling, the desired antibacterial coating can be obtained.

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