A water-based, long-lasting antibacterial and purifying coating, its preparation method and application

Abstract

This invention provides a water-based, long-lasting antibacterial and purifying coating and its application, belonging to the field of healthy environmental materials technology. The water-based, long-lasting antibacterial and purifying coating of this invention is prepared from 800-1200 parts of deionized water, 10-100 parts of polyoxometalate clusters, 100-450 parts of composite alkoxysilane, 30-90 parts of composite curing agent, and 5-20 parts of water-soluble polyether polyol, with the addition of a pH adjuster. It can be widely used in hospitals, homes, and catering establishments, and has advantages such as rapid sterilization, long service life, and resistance to peeling, without any adverse effects on human health.

Description

Technical Field

[0001] This invention belongs to the field of healthy environmental materials technology, specifically relating to a water-based, long-lasting antibacterial and purifying coating, its preparation method, and its application. Background Technology

[0002] With the continuous progress and development of modern society, an increasing number of pathogens have emerged, seriously threatening human health. Reducing the emergence, spread, and diffusion of pathogenic microorganisms is crucial for ensuring human health and socio-economic stability, making the search for new antibacterial materials imperative. The discovery and use of antibiotics have provided humanity with a powerful weapon against bacterial infections. However, the continuous overuse of antibiotics has led to a growing number of drug-resistant bacteria.

[0003] Antibiotic resistance is one of the top ten global public health threats facing humanity. The overuse of disinfectant and antimicrobial products during the COVID-19 pandemic accelerated the emergence and spread of superbugs, paving the way for their resurgence and leading to a surge in superbug infections in Europe and the United States. This could accelerate the arrival of a superbug pandemic and threaten future public health. If the spread of superbugs is not controlled, drug-resistant infections may become the next pandemic. Developing novel, durable, highly effective, broad-spectrum, and non-resistant first-generation antimicrobial and antiviral technologies is crucial for reducing the emergence, spread, and proliferation of superbugs and other types of antimicrobial resistance, and has become an urgent need in the industry.

[0004] Currently, there are paints on the market that contain silver and copper ions for sterilization. However, silver and copper ions are heavy metal ions. Heavy metals in their ionic state are easily absorbed by the pores of human skin, but cannot be digested and absorbed by the human body. Therefore, they can only accumulate in the kidneys, which can affect and damage the human immune system, nervous system, reproductive system, etc.

[0005] Polyoxometalate nanoclusters (POMs), also known as heteropolyacids or polyoxometalates, are a class of ultrafine, quantum-confined inorganic nanoclusters bridged by transition metals and oxygen atoms. They possess definite cluster molecular structures, unique self-assembly behaviors, and tunable redox properties, thus exhibiting physicochemical properties distinctly different from traditional transition metal oxides. Since the 1970s, POMs have gradually penetrated the biomedical field. Research has shown that the unique structure of POMs plays a crucial role in the recognition and binding of enzymes. POMs can bind to the RNA polymerase of *E. coli*, irreversibly inhibiting its reproduction. They can also inhibit viral adsorption to or penetration of target cells, thus exhibiting certain antibacterial, antiviral, and antifungal effects. Furthermore, POM has been proven to have extremely strong antibacterial activity against both Gram-negative and Gram-positive bacteria, including highly dangerous antibiotic-resistant superbugs (A. Bijelic, M. Aureliano and A. Rompel, Chem. Commun., 2018, DOI:10.1039 / C7CC07549A), making it an ideal green and environmentally friendly antibacterial agent.

[0006] However, most polyoxometalate clusters have good water solubility, and the resulting coatings are not resistant to water immersion, exhibiting poor long-term antibacterial performance. Therefore, developing a series of novel, long-lasting, and highly efficient antibacterial and purifying coatings based on polyoxometalate clusters as core antimicrobial agents is of great significance for the efficient, rapid, and persistent inactivation of harmful microorganisms such as superbugs. Summary of the Invention

[0007] In view of this, the purpose of this invention is to provide a water-based long-lasting antibacterial and purifying coating, its preparation method and application. The coating has long-lasting and durable antibacterial properties, can adhere strongly to the surface of various objects, is colorless and odorless, harmless to the human body, has a fast bactericidal speed and a broad bactericidal spectrum.

[0008] To achieve the above objectives, the present invention provides a water-based, long-lasting antibacterial and purifying coating, prepared from the following raw materials in parts by weight:

[0009] 800-1200 parts deionized water, 10-100 parts polymetallic oxy group, 100-450 parts composite alkoxysilane, 30-90 parts composite curing agent, and 5-20 parts water-soluble polyether polyol.

[0010] Furthermore, a pH adjuster was added to the raw materials to adjust the pH value of the system to 1.5–3.

[0011] The polyoxo cluster is a heteropolyacid or a polyoxo acid salt; the polyoxo cluster has phosphorus or silicon as the central atom and at least one of tungsten, molybdenum or vanadium as the coordinating atom.

[0012] The polyoxometalate is prepared by reacting a water-soluble metal salt with the heteropolyacid.

[0013] Preferably, the raw materials are: 900-1100 parts by mass of deionized water, 30-60 parts by mass of polyoxometalate clusters, 200-350 parts by mass of composite alkoxysilane, 40-80 parts by mass of composite curing agent, 8-17 parts by mass of water-soluble polyether polyol, and 0-4 parts by mass of pH adjuster; more preferably, 950-1050 parts by mass of deionized water, 40-50 parts by mass of polyoxometalate clusters, 250-300 parts by mass of composite alkoxysilane, 50-70 parts by mass of composite curing agent, 10-15 parts by mass of water-soluble polyether polyol, and 0-2 parts by mass of pH adjuster.

[0014] Preferably, the polyoxometalate cluster is one or more of tungsten-based heteropolyacids, tungsten-based polyoxometalates, molybdenum-based heteropolyacids, molybdenum-based polyoxometalates, vanadium-based heteropolyacids, or vanadium-based polyoxometalates; more preferably, it is one or more of tungsten-based heteropolyacids, tungsten-based polyoxometalates, molybdenum-based heteropolyacids, or molybdenum-based polyoxometalates; and even more preferably, it is one or two of tungsten-based heteropolyacids and tungsten-based polyoxometalates.

[0015] Preferably, the composite alkoxysilane is a combination of epoxysilane and tetraalkoxysilane.

[0016] Preferably, the epoxy silane includes, but is not limited to, β-(3,4-epoxycyclohexyl)-ethyltriethoxysilane, β-(3,4-epoxycyclohexyl)-ethyltrimethoxysilane, γ-glycidyl etheroxypropyltrimethoxysilane (KH560), γ-glycidyl etheroxypropyltriethoxysilane (KH561), 3-(2,3-epoxypropoxy)propylmethyldiethoxysilane, or 3-(2,3-epoxypropoxy)propylmethyldimethoxysilane; preferably, any one of β-(3,4-epoxycyclohexyl)-ethyltriethoxysilane, γ-glycidyl etheroxypropyltrimethoxysilane, γ-glycidyl etheroxypropyltriethoxysilane, or 3-(2,3-epoxypropoxy)propylmethyldimethoxysilane; more preferably, γ-glycidyl etheroxypropyltrimethoxysilane or γ-glycidyl etheroxypropyltriethoxysilane.

[0017] Preferably, the tetraalkoxysilane includes, but is not limited to, one or both of tetramethoxysilane and tetraethoxysilane; more preferably, it is tetraethoxysilane.

[0018] Preferably, the ratio of epoxy silane to tetraalkoxy silane is 1:1 to 4:1. The phosphotungstic acid / silicotungstic acid solution prepared by ion exchange of epoxy silane and tetraalkoxy silane has strong acidity. When the composite alkoxy silane is added to it, it will undergo in-situ hydrolysis under acidic conditions and graft a small amount onto the surface of POM polyoxometalate clusters. This is beneficial for fixing POM in the film and preventing the POM in the formed long-lasting antibacterial coating from dissolving or migrating in water. The composite alkoxy silane film-forming system used in this invention uses siloxanes that can react with polyoxometalate clusters and graft onto the surface of nanoclusters. After firmly locking the POM nanoclusters into a 3D network structure of the siloxane coating, the dissolution of POM is effectively reduced, achieving long-lasting antibacterial properties.

[0019] Preferably, the composite curing agent is a complex of a polybasic organic carboxylic acid and a nitrogen-containing compound.

[0020] Preferably, the polycarboxylic acid includes, but is not limited to, one or more of fumaric acid, tartaric acid, citric acid, trimellitic anhydride, itaconic acid, and pyromellitic anhydride; the polycarboxylic acid is preferably trimellitic anhydride or itaconic acid, more preferably itaconic acid; the nitrogen-containing compound is preferably dicyandiamide or aziridine crosslinking agent.

[0021] Preferably, the weight ratio of the poly-organic carboxylic acid to the nitrogen-containing compound is 2.5 to 4:1.

[0022] This invention utilizes a complex of poly-organic carboxylic acids and nitrogen-containing compounds as a composite curing agent. These compounds can undergo condensation reactions with silanol groups in the hydrolyzed alkoxy groups within the system, as well as addition reactions with epoxy groups, forming a 3D network structure. This improves the coating's film-forming properties, adhesion, hardness, and scrub resistance, imparting durable antibacterial properties. The composite-cured and cross-linked coating significantly improves its water resistance, chemical resistance, dry and wet friction resistance, surface anti-sticking properties, coating firmness, and adhesion to special substrates. The curing agent and the composite alkoxysilane work synergistically to impart water resistance and durable antibacterial properties to the coating.

[0023] Preferably, the water-soluble polyether polyol includes, but is not limited to, one or more of polyethylene glycol, polypropylene glycol, alcohol ether modified polyhydroxy polymers, and fatty alcohol polyoxyethylene ethers, preferably polyethylene glycol and / or polypropylene glycol, more preferably polyethylene glycol; the water-soluble polyether polyol has a molecular weight of 200-2000, more preferably 200-800.

[0024] Preferably, the pH adjuster is 2-amino-2-methyl-1-propanol (AMP-95).

[0025] Another object of the present invention is to provide a method for preparing the coating, comprising the following steps:

[0026] 1) A heteropolyacid aqueous solution was prepared by cation exchange, and a pH adjuster was added to adjust the pH value to 1.5-3;

[0027] 2) Dissolve the water-soluble polyether polyol in the heteropolyacid aqueous solution prepared in step (1) at room temperature to obtain the first mixture;

[0028] 3) The composite alkoxysilane is slowly added dropwise to the first mixture and mixed evenly to obtain the second mixture;

[0029] 4) The second mixture prepared in step (3) is mixed with the composite curing agent in a third mixing to obtain a water-based durable antibacterial and purifying coating.

[0030] Preferably, the specific steps of step (1) are as follows: water-soluble metal salts are reacted with phosphorus or silicon sources to prepare heteropolyacid nascent solution; then hydrogen-type ion exchange resin is used for ion exchange and desalination treatment, and pH adjuster is added to adjust the pH value to 1.5-3.

[0031] Preferably, the water-soluble metal salt is any one of water-soluble tungstate, water-soluble molybdate, or water-soluble vanadate; the phosphorus source is phosphoric acid or water-soluble phosphate; and the silicon source is water-soluble silicate.

[0032] Preferably, the tungsten-based heteropolyacid is one or both of phosphotungstic acid and silicotungstic acid, preferably phosphotungstic acid; the tungsten-based polyoxometalate is one or both of phosphotungstate and silicotungstate, more preferably phosphotungstate.

[0033] Preferably, the tungsten-based heteropolyacid is prepared by cation exchange after mixing tungstate with one or more of water-soluble phosphoric acid, phosphate or silicate; the tungsten-based polyoxometalate is preferably prepared by reacting tungsten-based heteropolyacid with water-soluble metal salt.

[0034] Preferably, the tungstate comprises, but is not limited to, sodium tungstate and ammonium metatungstate, with sodium tungstate being the most preferred.

[0035] Preferably, the phosphate is one or more of disodium hydrogen phosphate, sodium dihydrogen phosphate, potassium dihydrogen phosphate, dipotassium hydrogen phosphate, diammonium hydrogen phosphate, or ammonium dihydrogen phosphate, and more preferably one or more of disodium hydrogen phosphate, potassium dihydrogen phosphate, or ammonium dihydrogen phosphate.

[0036] Preferably, the silicate is water-soluble sodium silicate or potassium silicate, and more preferably water-soluble potassium silicate.

[0037] Preferably, the water-soluble metal salt includes, but is not limited to, one or more of silver nitrate, copper nitrate, copper chloride, copper sulfate, manganese chloride, manganese nitrate, manganese sulfate, yttrium chloride, yttrium nitrate, lanthanum chloride, lanthanum nitrate, cobalt chloride, zinc chloride, zinc nitrate, cerium nitrate, zirconium nitrate, ferric chloride, or ferric nitrate; more preferably, one or more of silver nitrate, copper nitrate, zinc nitrate, manganese nitrate, or manganese chloride.

[0038] Preferably, step (3) further includes the following steps: slowly dissolving the water-soluble metal salt in the second mixture, and then stirring at room temperature overnight to obtain a third mixture containing polyoxometalates.

[0039] This invention utilizes a cation exchange method to prepare a polyoxometalate solution from a polyoxometalate aqueous solution and a water-soluble metal salt in situ. To avoid the potential impact of unreacted water-soluble metal salts on antibacterial properties, an appropriate amount of hydrogen-form cation exchange resin is added to the solution after the reaction to remove metal ions such as silver, copper, zinc, and manganese from the system. Regarding the water-soluble nitrate system, nitrate ions (NO3) will be generated during the preparation of polyoxometalates from polyoxometalates and water-soluble metal salts. - Negative ions such as NO3- are present in the coating system and may cause long-term corrosion to the metal surface after spraying. Therefore, this invention uses a commercially available sodium bicarbonate or saturated carbon dioxide aqueous solution-activated nitrate-removing ion exchange resin to perform nitrate ion exchange, removing NO3- from the solution. - By interacting with HCO3 on the ion exchange resin - The resin is removed through exchange. After exchange saturation, the resin can be regenerated using NaHCO3 or carbon dioxide aqueous solution for reuse.

[0040] Commercially available polyoxometalate salts (such as silver phosphotungsten, copper phosphotungsten, zinc phosphotungsten, and manganese phosphotungsten) are expensive, have poor water solubility, and produce large particles with opaque coatings. This invention prepares polyoxometalates by adding a water-soluble metal salt after step 3 to prepare phosphotungsten in situ, resulting in a transparent solution and small polyoxometalate particles. Furthermore, a nitrate-removing resin is used to eliminate nitric acid and nitrates introduced by the water-soluble metal salt, preventing potential corrosion of the metal by the prepared coating.

[0041] This invention integrates sol-gel technology with nanoscale particle surface engineering modification technology, pioneering a low-temperature sol-gel method for preparing multi-metal-oxygen clusters. The all-aqueous reaction system features low reaction temperature, mild conditions, safety, and environmental friendliness. Equipment requirements are simple; ordinary glass reactors can be used for production. The reaction exhibits good consistency and is easily replicated for mass production.

[0042] The present invention also provides an application of the above-mentioned coating, wherein the coating is applied to the surface of plastic, ceramic, metal, ore, glass or wood.

[0043] Preferably, the coating can be applied by roller coating, spraying or brushing.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The water-based long-lasting antibacterial and purifying coating of the present invention is composed of a three-dimensional molecular network structure of hydrolyzed siloxane and a polyoxometalate cluster antibacterial agent. The siloxane used can be grafted onto the surface of the polyoxometalate cluster particles to form organic-inorganic cross-linking points, thereby firmly locking the polyoxometalate cluster nanoclusters in the coating, effectively preventing the migration of the polyoxometalate cluster antibacterial agent, thus giving the coating long-lasting and durable antibacterial properties.

[0046] This invention utilizes nanomaterial surface engineering modification technology to modify the surface of polyoxometalate clusters (POMs) with water-soluble polyether polyols. At the nanoscale, this involves grafting biocompatible organic molecules onto the surface particles of single-metal oxide atoms, thereby imparting or enhancing the biocompatibility of the developed metal oxide atomic clusters and reducing their biotoxicity. Furthermore, the organic-inorganic modification effectively improves the compatibility of nano-antibacterial materials with traditional substrates, facilitating the firm bonding of nano-antibacterial materials to polymer coatings / films / plastics, reducing or inhibiting their migration to surfaces and into the air, and minimizing the environmental impact of nanomaterials. In-situ grafting modification technology grafts biocompatible water-soluble polyether polyols onto the surface of polyoxometalate clusters, improving the biocompatibility of POMs, reducing their toxicity, and expanding their applications.

[0047] The water-based long-lasting antibacterial and purifying coating of this invention is a transparent and durable coating that can kill germs within twenty minutes, effectively prevent the growth of germs, and can adhere strongly to the surface of various objects. It can be applied to the surface of various substrates to continuously protect them from dangerous pathogens, create a continuously clean surface and maintain a healthy indoor space, and achieve an intelligent defense effect.

[0048] The water-based, long-lasting antibacterial and purifying coating of this invention is colorless, odorless, and harmless to the human body. It can be applied to the surface of most objects, such as building materials, metals, plastics, fabrics, paper, and glass products, through processes such as brushing, spraying, and roller coating. It has strong adhesion and can form a long-lasting sterile space, effectively preventing the contact transmission of germs. It is widely applicable in densely populated places such as hospitals, schools, public transportation, and homes. Detailed Implementation

[0049] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.

[0050] All reagents used in the embodiments of this invention are chemically pure and can be used directly. All reagents were purchased from companies such as Guangdong Wengjiang Chemical Reagent Co., Ltd. and Hangzhou Jessica Chemical Co., Ltd. In the following embodiments, unless otherwise specified, all parts are parts by weight.

[0051] Example 1

[0052] A water-based, long-lasting antibacterial and purifying coating is prepared as follows:

[0053] 1) Dissolve 66 parts by weight of water-soluble sodium tungstate in 1000 parts of deionized water, and then weigh an appropriate amount of anhydrous sodium dihydrogen phosphate in tungstate solution to prepare phosphotungstic acid primary solution. Then, pass the phosphotungstic acid primary solution through a chromatography column containing hydrogen-form ion exchange resin for ion exchange and desalting treatment. Then, adjust the pH of the solution to 2 with an appropriate amount of AMP-95 to obtain a high-purity phosphotungstic acid aqueous solution. The obtained solution contains approximately 48 parts of phosphotungstic acid (PTA).

[0054] 2) Weigh 5 parts of water-soluble polyethylene glycol 200 and dissolve it in the above phosphotungstic acid aqueous solution by stirring at room temperature to obtain the first mixture;

[0055] 3) Weigh 150 parts of γ-glycidyl ether oxypropyltrimethoxysilane (KH560) and 45 parts of tetraethoxysilane and stir for 30 minutes. Then slowly add the mixture dropwise to the first mixture and stir overnight at room temperature to obtain the second mixture.

[0056] 4) Weigh 45 parts of itaconic acid and 15 parts of dicyandiamide and dissolve them in the second mixture. Stir at room temperature to dissolve, then continue stirring at 60 degrees Celsius for 4 hours. Slowly cool to room temperature to obtain a long-lasting antibacterial and purifying coating of phosphotungstic acid (PTA) polymetallic oxy-cluster.

[0057] Example 2

[0058] A water-based, long-lasting antibacterial and purifying coating is prepared as follows:

[0059] 1) Dissolve 66 parts by weight of water-soluble sodium tungstate in 1000 parts of deionized water, and then weigh phosphoric acid and dissolve it in the sodium tungstate solution according to an equimolar ratio to prepare a phosphotungstic acid primary solution; then pass the phosphotungstic acid primary solution through a chromatography column containing hydrogen-form ion exchange resin for ion exchange and desalting treatment, and then adjust the pH of the solution to 2.5 with an appropriate amount of AMP-95 to obtain a high-purity phosphotungstic acid (PTA) aqueous solution, which contains approximately 48 parts of PTA;

[0060] 2) Weigh 5 parts of water-soluble polyethylene glycol and dissolve it in phosphotungstic acid aqueous solution at room temperature to obtain the first mixture;

[0061] 3) Weigh 150 parts of γ-glycidyl ether oxypropyltrimethoxysilane (KH560) and 45 parts of tetraethoxysilane and stir for 30 minutes. Then slowly add the mixture dropwise to the first mixture and stir at 80°C for 2 hours. Then cool to room temperature to obtain the second mixture.

[0062] 4) Weigh an appropriate amount of water-soluble silver nitrate, slowly dissolve it in the second mixture, and then stir overnight at room temperature to obtain the third mixture, wherein the molar ratio of silver nitrate to sodium tungstate is 3:1.

[0063] 5) Weigh 50g of hydrogen-form ion exchange resin and stir it into the third mixture. Continue stirring for 30 minutes, then filter to remove the ion exchange resin; then add 150g of [unspecified ingredient] to the filtrate. A-62MP nitrate removal special resin was stirred continuously for 30 minutes, and then filtered to obtain the fourth mixture.

[0064] 6) Weigh 23 parts of trimellitic anhydride and 7 parts of water-soluble aziridine crosslinking agent and stir to dissolve them in the above fourth mixture. Then stir continuously at 80°C for 1 hour and slowly cool to room temperature to obtain a silver phosphotungstic acid (Ag@PTA) polymetallic oxygen cluster durable antibacterial and purifying coating. The obtained coating solution contains about 53 parts of Ag@PTA polymetallic oxygen cluster.

[0065] Example 3

[0066] A water-based, long-lasting antibacterial and purifying coating is prepared as follows:

[0067] 1) Dissolve 66 parts by weight of water-soluble sodium tungstate in 1000 parts by weight of deionized water. Then, weigh an appropriate amount of water-soluble silicate and dissolve it in the tungstate solution to prepare a silicotungstic acid primary solution. The silicotungstic acid primary solution is then subjected to ion exchange and desalting treatment by passing it through a chromatography column containing hydrogen-form ion exchange resin. The pH of the solution is then adjusted to 3 with an appropriate amount of AMP-95 to obtain a high-purity silicotungstic acid (STA) aqueous solution, in which approximately 50 parts by weight of STA are obtained.

[0068] 2) Weigh 10 parts of water-soluble polypropylene glycol 400 and dissolve it in the above silicotungstic acid aqueous solution by stirring at room temperature to obtain the first mixture;

[0069] 3) Weigh 160 parts of β-(3,4-epoxycyclohexyl)-ethyltriethoxysilane and 80 parts of tetraethoxysilane and stir for 30 minutes. Then slowly add the mixture dropwise to the first mixture and stir at room temperature for 4 hours to obtain the second mixture.

[0070] 4) Weigh an appropriate amount of water-soluble silver nitrate, slowly dissolve it in the solution, then heat it to 60°C and stir overnight to obtain the third mixture, wherein the molar ratio of silver nitrate to sodium tungstate is 3:1.

[0071] 5) Weigh an appropriate amount of hydrogen-form ion exchange resin and stir it into the third mixture. Continue stirring for 30 minutes, then filter to remove the ion exchange resin; then add 100g of [unspecified ingredient] to the filtrate. A-62MP nitrate removal special resin was stirred continuously for 30 minutes, and then filtered to obtain the fourth mixture.

[0072] 6) Weigh 51 parts of pyromellitic anhydride and 15 parts of dicyandiamide and stir to dissolve them in the fourth mixture. Then stir continuously at room temperature for 6 hours to obtain a durable antibacterial and purifying coating of silver silicotungstate (Ag@STA) polymetallic oxygen clusters. The resulting coating solution contains approximately 59 parts of Ag@STA polymetallic oxygen clusters.

[0073] Example 4

[0074] A water-based, long-lasting antibacterial and purifying coating is prepared as follows:

[0075] 1) Dissolve 66 parts by weight of water-soluble ammonium metatungstate in 1000 parts by weight of deionized water. Then, weigh an appropriate amount of sodium dihydrogen phosphate dihydrate and dissolve it in the ammonium metatungstate solution to prepare a phosphotungstic acid (PTA) primary solution. The PTA primary solution is then subjected to ion exchange and desalting treatment using a chromatography column containing hydrogen-form ion exchange resin. The pH of the solution is then adjusted to 1.5 using AMP-95 to obtain a high-purity PTA aqueous solution. The resulting solution contains approximately 48 parts by weight of PTA.

[0076] 2) Weigh 5 parts of water-soluble alcohol ether modified polyhydroxy polymer, stir at room temperature to dissolve in aqueous solution, and prepare the first mixture;

[0077] 3) Weigh 75 parts of γ-glycidyl ether oxypropyltriethoxysilane (KH561) and 75 parts of tetramethoxysilane and stir for 60 minutes. Then slowly add the mixture dropwise to the first mixture, stir at 80 degrees Celsius for 2 hours, and then cool to room temperature to obtain the second mixture.

[0078] 4) Weigh an appropriate amount of water-soluble copper nitrate, slowly dissolve it in the second mixture, and then stir overnight at room temperature to obtain the third mixture, wherein the molar ratio of copper nitrate to sodium tungstate is 1.5:1;

[0079] 5) Weigh an appropriate amount of hydrogen-form ion exchange resin and stir it into the third mixture. Continue stirring for 30 minutes, then filter to remove the ion exchange resin; then add 100g of [unspecified ingredient] to the filtrate. A-62MP nitrate removal special resin was stirred continuously for 30 minutes, and then filtered to obtain the fourth mixture.

[0080] 6) Weigh 23 parts of itaconic acid and 7 parts of dicyandiamide and stir to dissolve in the fourth mixture. Then stir continuously at 80 degrees Celsius for 1 hour and slowly cool to room temperature to obtain a durable antibacterial and purifying coating of copper phosphate (Cu@PTA) polymetallic oxygen clusters. The resulting coating solution contains approximately 49.5 parts of Cu@PTA polymetallic oxygen clusters.

[0081] Example 5

[0082] A water-based, long-lasting antibacterial and purifying coating is prepared as follows:

[0083] 1) Dissolve 99 parts by weight of water-soluble sodium tungstate in 1000 parts by weight of deionized water. Then, weigh an appropriate amount of anhydrous potassium dihydrogen phosphate and dissolve it in the sodium tungstate solution to prepare a phosphotungstic acid (PTA) primary solution. The PTA primary solution is then subjected to ion exchange and desalting treatment using a chromatography column containing hydrogen-form ion exchange resin. The pH of the solution is then adjusted to 3 using AMP-95 to obtain a high-purity PTA aqueous solution. The resulting solution contains approximately 72 parts by weight of PTA.

[0084] 2) Weigh 20 parts of water-soluble polyethylene glycol 800 and dissolve it in the above phosphotungstic acid aqueous solution by stirring at room temperature to obtain the first mixture;

[0085] 3) Weigh 140 parts of γ-glycidyl ether oxypropyltrimethoxysilane (KH560) and 290 parts of tetraethoxysilane and stir for 60 minutes. Then slowly add the mixture dropwise to the first mixture and stir overnight at room temperature to obtain the second mixture.

[0086] 4) Weigh an appropriate amount of water-soluble zinc nitrate, slowly dissolve it in the second mixture, stir overnight at room temperature to obtain the third mixture, wherein the molar ratio of zinc nitrate to sodium tungstate is 1.5:1;

[0087] 5) Weigh an appropriate amount of hydrogen-form ion exchange resin and stir it into the third mixture. Continue stirring for 30 minutes, then filter to remove the ion exchange resin; then add 200g of [unspecified ingredient] to the filtrate. A-62MP nitrate removal special resin was stirred continuously for 60 minutes, and then filtered to obtain the fourth mixture.

[0088] 6) Weigh 80 parts of fumaric acid and 30 parts of dicyandiamide and stir to dissolve them in the fourth mixture. Then stir continuously at 60 degrees Celsius for 4 hours and slowly cool to room temperature to obtain a long-lasting antibacterial and purifying coating of zinc phosphotungstic acid (Zn@PTA) polymetallic oxygen clusters. The resulting coating solution contains approximately 74.5 parts of Zn@PTA polymetallic oxygen clusters.

[0089] Example 6

[0090] A water-based, long-lasting antibacterial and purifying coating is prepared as follows:

[0091] 1) Dissolve 33 parts by weight of water-soluble sodium tungstate in 1000 parts of deionized water, and then weigh an appropriate amount of disodium hydrogen phosphate and dissolve it in the sodium tungstate solution to prepare a phosphotungstic acid primary solution. The phosphotungstic acid primary solution is then subjected to ion exchange and desalting treatment by passing it through a chromatography column containing hydrogen-form ion exchange resin. The pH of the solution is then adjusted to 2.5 using AMP-95 to obtain a high-purity phosphotungstic acid (PTA) aqueous solution, which contains approximately 24 parts of PTA.

[0092] 2) Weigh 5 parts of water-soluble fatty alcohol polyoxyethylene ether, stir at room temperature and dissolve in phosphotungstic acid aqueous solution to prepare the first mixture;

[0093] 3) Weigh 75 parts of γ-glycidyl ether oxypropyltrimethoxysilane (KH560) and 25 parts of tetraethoxysilane and stir for 30 minutes. Then slowly add the mixture dropwise to the first mixture and stir at room temperature for 6 hours to obtain the second mixture.

[0094] 4) Weigh an appropriate amount of water-soluble manganese chloride, slowly dissolve it in the second mixture, and then stir at room temperature for 6 hours to obtain the third mixture, wherein the molar ratio of manganese chloride to sodium tungstate is 1.5:1.

[0095] 5) Weigh 23 parts of itaconic acid and 7 parts of water-soluble aziridine crosslinking agent and stir to dissolve them in the third mixture. Then stir continuously at room temperature overnight to obtain a long-lasting antibacterial and purifying coating of manganese phosphotungstic acid (Mn@PTA) polymetallic oxygen clusters. The resulting coating solution contains approximately 24.6 parts of Mn@PTA polymetallic oxygen clusters.

[0096] Comparative Example 1

[0097] A silver phosphotungstic acid antibacterial coating is prepared as follows:

[0098] 1) Dissolve 66 parts by weight of water-soluble sodium tungstate in 1000 parts of deionized water, and then weigh phosphoric acid and dissolve it in the sodium tungstate solution according to the equimolar ratio to prepare a phosphotungstic acid primary solution; then pass the phosphotungstic acid primary solution through a chromatography column containing hydrogen-form ion exchange resin for ion exchange and desalting treatment, and then adjust the pH of the solution to 2.5 with an appropriate amount of AMP-95 to obtain a high-purity phosphotungstic acid (PTA) aqueous solution;

[0099] 2) Weigh 5 parts of water-soluble polyethylene glycol and dissolve it in phosphotungstic acid aqueous solution at room temperature to obtain the first mixture;

[0100] 4) Weigh an appropriate amount of water-soluble silver nitrate, slowly dissolve it in the first mixture, and then stir overnight at room temperature to obtain the second mixture, wherein the molar ratio of silver nitrate to sodium tungstate is 3:1.

[0101] 5) Weigh 50g of hydrogen-form ion exchange resin and stir it into the third mixture. Continue stirring for 30 minutes, then filter to remove the ion exchange resin; then add 150g of [unspecified ingredient] to the filtrate. A-62MP nitrate-removing special resin was continuously stirred for 30 minutes and then filtered to obtain a silver phosphotungstate (SPT) multi-metal oxy-cluster antibacterial and purifying coating.

[0102] Comparative Example 2

[0103] An antibacterial and purifying coating was prepared using commercially available polymetallic oxy-group salts (silver phosphotungsten, copper phosphotungsten, zinc phosphotungsten, and manganese phosphotungsten) as raw materials, with the remaining raw materials as described in Example 2.

[0104] The preparation method is the same as in Example 2, except that in Comparative Example 2, a commercially available polyoxometalate cluster salt is directly added, omitting the steps of preparing the phosphotungstic acid nascent solution in step (1) and adding the water-soluble metal salt in step (4). The resulting coating is opaque. Commercially available polyoxometalate cluster salts are expensive and have poor water solubility, making it difficult to obtain a transparent coating.

[0105] Commercially available nano-silver (Shandong Yousuo Chemical Technology Co., Ltd., colorless nano-silver solution, 4nm, 2000ppm) was used as a control. The following experiments were conducted on the antibacterial and purifying coatings prepared in Examples 1-6:

[0106] Bond strength test:

[0107] To verify the adhesion of the long-lasting antibacterial coating to surfaces such as plastics, glass, and metals, the present invention applied the nano-antibacterial coating prepared in the above embodiments to rectangular glass surfaces with dimensions of approximately 150mm x 100mm and 3mm, with a coating amount of approximately 20g / m². 2 After natural drying and curing for 24 hours, the adhesion strength of the nano-coatings on various substrate surfaces was tested using GB / T 9286-2021 "Cross-cut Test Method for Paints and Varnishes" (using a cross-cut tester on glass). The experimental results were graded according to the standard. The results are shown in Table 1. The antibacterial coatings prepared in Examples 1-6 exhibit excellent adhesion performance on glass surfaces. Compared with Example 2, the comparative example, which used a composite alkoxysilane and composite curing agent system, could not form a siloxane nano-coating system. The prepared silver phosphotungstenate had no chemical adhesion to the substrate, poor adhesion performance, poor water resistance, and extremely poor durability.

[0108] Antibacterial properties and antibacterial durability test

[0109] Disinfectants such as 84 disinfectant, bleaching powder, and alcohol play important roles in our daily lives. However, due to their highly reactive nature, while possessing strong disinfection capabilities, they can also rapidly decompose or react with other substances, rendering them ineffective. Therefore, repeated use is necessary to maintain their effectiveness. This invention involves spraying the prepared nano-antibacterial coating onto a 5x5cm, 2mm thick deep UV-activated PMMA plate and curing it at room temperature for 24 hours. The latest group standard T / CIAA 019-2023, "Performance and Evaluation of Surface-Sprayed Fast-Acting and Long-Lasting Antibacterial Agents," was used to test the developed water-based long-lasting antibacterial nano-coating's bactericidal rate against Escherichia coli (contact time 20 min), its long-lasting antibacterial performance (tested after 7 days of sample placement), and its antibacterial durability (UV aging 100 hours) according to the same standard. The samples were rinsed with water 100 times to test their antibacterial properties and verify the coating's water resistance. Simultaneously, the bactericidal rate against methicillin-resistant Staphylococcus aureus (MRSA) was tested according to the method described in ISO 22196:2011 (contact time 24 hours). The results are shown in Table 1.

[0110] Table 1

[0111]

[0112]

[0113] As shown in Table 1, the water-based long-lasting antibacterial coating developed in this invention is both fast-acting and long-lasting, simple and convenient to use, and can "stablely exert" its long-lasting antibacterial performance throughout its life cycle, achieving rapid and long-lasting control or reduction of the number of pathogenic microorganisms on the surface of objects. This nano-coating possesses excellent fast-acting and long-lasting antibacterial properties, while also being environmentally friendly and requiring minimal operational expertise. It can significantly reduce the survival rate of pathogenic microorganisms, inhibit and control the excessive proliferation of pathogenic microorganisms in indoor environments, thereby reducing the risk of cross-infection. Antibiotic resistance is one of the top ten global public health threats facing humanity, and superbugs are becoming a "major global health risk." Studies have shown that the prepared metal-doped multi-metal cluster antibacterial coating has excellent inactivation activity against methicillin-resistant Staphylococcus aureus (MRSA).

[0114] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An aqueous durable antimicrobial sanitizing coating, characterized in that, Prepared from the following raw materials in mass fraction: Deionized water 800-1200 parts, polyoxometalate 10-100 parts, composite alkoxy silane 100-450 parts, composite curing agent 30-90 parts, water-soluble polyether polyol 5-20 parts; And a pH adjuster is added to the raw materials, which is used to adjust the pH value of the system to 1.5-3; The polyoxometalate is a heteropoly acid or a polyoxometalate salt; the polyoxometalate has phosphorus or silicon as a central atom and at least one of tungsten, molybdenum or vanadium as a coordination atom; The polyoxometalate salt is prepared by reacting a water-soluble metal salt with a heteropoly acid.

2. The coating of claim 1, wherein, The polyoxometalate is one or more of tungsten-based heteropoly acid, tungsten-based polyoxometalate, molybdenum-based heteropoly acid, molybdenum-based polyoxometalate, vanadium-based heteropoly acid or vanadium-based polyoxometalate.

3. The coating of claim 1, wherein, The composite alkoxy silane is a combination of epoxy silane and tetraalkoxysilane; the weight ratio of the epoxy silane and tetraalkoxysilane is 1:1-4:

1.

4. The coating of claim 1, wherein, The composite curing agent is a combination of a polybasic organic carboxylic acid and a nitrogen-containing compound; the weight ratio of the polybasic organic carboxylic acid and the nitrogen-containing compound is 2.5-4:

1.

5. The coating of claim 1, wherein, The water-soluble polyether polyol includes one or more of polyethylene glycol, polypropylene glycol, alcohol ether modified polyol polymer and fatty alcohol polyoxyethylene ether.

6. The method of claim 1, wherein the coating is prepared by a method comprising: The method comprises the following steps: 1) Prepare a heteropoly acid aqueous solution by cation exchange method, and add a pH adjuster to adjust the pH value to 1.5-3; 2) Dissolve the water-soluble polyether polyol in the heteropoly acid aqueous solution prepared in step 1) at room temperature under stirring to obtain a first mixture; 3) Slowly drop the composite alkoxy silane into the first mixture and mix uniformly to obtain a second mixture; 4) Mix the second mixture prepared in step 3) with the composite curing agent to obtain a water-based durable antibacterial and purifying coating.

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