Preparation method and application of UV resin coating

Abstract

The present invention relates to the field of coating technology, and specifically to a method for preparing a UV resin coating and its application. The present invention overcomes the shortcomings of existing UV resin coatings in wood applications, such as poor wear resistance and poor antibacterial properties. The present invention uses fluorine-containing water-based polyurethane acrylate dispersion, water-based hydroxyl polyurethane, modified tea polyphenols, polymerization inhibitors, etc. as raw materials to prepare component A; uses functionalized nano-cerium dioxide, silver-loaded nano-silica, leveling agents, composite photoinitiators, etc. as raw materials to prepare component B; and finally mixes component A and component B with an isocyanate curing agent to obtain a UV resin coating; the fluorine-containing water-based polyurethane acrylate dispersion is prepared using polytetramethylene glycol, polycarbonate diol, perfluoropolyether diol, etc. as raw materials; and the modified tea polyphenols are prepared using tea polyphenols and methacrylic anhydride as raw materials. The UV resin coating prepared by the present invention is a water-based UV resin coating, which is suitable for wooden floors and has the advantages of improved wear resistance and antibacterial properties.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, in particular to a preparation method of a UV resin coating and application thereof. Background Art

[0002] As people's demands for higher-quality home environments continue to rise, wood flooring, thanks to its unique natural texture, creates a warm atmosphere, and provides a gentle feel when stepped on, has become increasingly popular among families. In the field of home wood flooring, water-based UV resin offers significant advantages over traditional UV resins. Using water as a dispersion medium, water-based UV resins offer low VOC emissions, are environmentally friendly, and are safe. They significantly reduce indoor air pollution, meeting the modern family's pursuit of a healthy living environment.

[0003] Water-based UV resin coatings can be categorized into several types based on resin type, with water-based polyurethane acrylate resins being the most widely used. When applied to wood floors, these resins exhibit numerous advantages, including excellent flexibility and adhesion, adaptability to minor deformations caused by environmental changes, and resistance to cracking and peeling. The cured coating also exhibits a certain degree of wear and water resistance, effectively protecting the floor.

[0004] However, when laying wooden floors in homes with pets or children, the floors face severe challenges. The scratching of pets' claws and the daily activities of children place extremely high demands on the wear resistance of the floor. At the same time, pet hair, excrement, and germs carried by children during play make the antibacterial properties of the floor critical. Although existing water-based polyurethane acrylate resins have a certain degree of wear resistance, they are still prone to scratches when faced with long-term and frequent scratching by pets and high-intensity use by children, affecting the appearance and service life; in terms of antibacterial properties, their antibacterial ability is limited, making it difficult to effectively inhibit the growth of various bacteria and unable to fully guarantee family hygiene and safety. Therefore, there is an urgent need to develop a UV resin coating with good wear resistance and strong antibacterial properties to meet the high-performance needs of such families for wood floor coatings and provide families with a better quality, durable and healthy floor protection solution.

[0005] Therefore, a preparation method of UV resin coating and its application are proposed. Summary of the Invention

[0006] The purpose of the present invention is to provide a method for preparing a UV resin coating and its application. The present invention uses a fluorine-containing waterborne polyurethane acrylate dispersion, waterborne hydroxyl polyurethane, modified tea polyphenols, a polymerization inhibitor, and the like as raw materials to prepare component A; uses functionalized nano-cerium dioxide, silver-loaded nano-silica, a leveling agent, a composite photoinitiator, and the like as raw materials to prepare component B; and finally, components A and B are mixed with an isocyanate curing agent to obtain a UV resin coating; the fluorine-containing waterborne polyurethane acrylate dispersion is prepared using polytetramethylene glycol, polycarbonate diol, perfluoropolyether diol, and the like as raw materials; and the modified tea polyphenols are prepared using tea polyphenols and methacrylic anhydride as raw materials. The UV resin coating prepared by the present invention is a waterborne UV resin coating suitable for coating wooden floors and has the advantages of improved wear resistance and antibacterial properties.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] In one aspect, the present invention provides a method for preparing a UV resin coating. The method for preparing the UV resin coating comprises the following steps, based on parts by weight: uniformly mixing a premix of component A and component B; subsequently adding 16-20 parts of an isocyanate curing agent; and continuing stirring for 5 minutes to obtain the UV resin coating.

[0009] Preparation of component A: 100 parts of fluorine-containing waterborne polyurethane acrylate dispersion and 45-55 parts of waterborne hydroxyl polyurethane dispersion are uniformly mixed, and then dipropylene glycol dimethyl ether and polyurethane dispersant, 2-3 parts of modified tea polyphenols, polymerization inhibitor, and 4 parts of composite photoinitiator are added in sequence, and finally filtered to obtain component A;

[0010] Preparation of component B: Mix 7 parts of dipropylene glycol dimethyl ether with 13 parts of deionized water; add 0.4 parts of wetting agent; then slowly add 4-6 parts of functionalized nano-cerium dioxide and 2-3 parts of silver-loaded nano-silica, and disperse at high speed for 20 minutes; then add 0.4 parts of leveling agent, 0.2 parts of defoaming agent and 1.1 parts of thickener in sequence; finally filter to obtain the component B premix.

[0011] Preferably, the composite photoinitiator is obtained by mixing 1-hydroxycyclohexyl phenyl ketone and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide in a weight ratio of 1:1 and then dissolving the mixture in dipropylene glycol dimethyl ether.

[0012] Preferably, the preparation method of the fluorine-containing waterborne polyurethane acrylate dispersion is as follows: dehydrating a mixture of 55 parts of polytetramethylene glycol, 15 parts of polycarbonate diol, 8-12 parts of perfluoropolyether diol and 4.5 parts of dimethylol propionic acid; subsequently adding 26-28 parts of isophorone diisocyanate, 30 parts of acetone and 0.08 parts of dibutyltin dilaurate, and reacting at 75°C for 4 hours to obtain a prepolymer; after the reaction is completed, lowering the system temperature to 60°C, adding 9 parts of hydroxyethyl acrylate and reacting for 2 hours; then adding 3.4 parts of triethylamine and reacting for 30 minutes, dispersing the obtained neutralized prepolymer solution in water under high shear force; finally, distilling under reduced pressure at 50°C to obtain a fluorine-containing waterborne polyurethane acrylate dispersion with a solid content of 35%, wherein the molecular weight of the polycarbonate diol is 1000-2000, and the molecular weight of the perfluoropolyether diol is 1000-2000.

[0013] Preferably, the preparation method of modified tea polyphenols is as follows: under nitrogen protection, 10 parts of tea polyphenols are dissolved in 100 parts of anhydrous acetone, and 12 parts of triethylamine are added; 16-20 parts of methacrylic anhydride are added at 5°C; then the reaction is carried out at 5°C for 12 hours, and then the temperature is raised to 25°C and the reaction is continued for 6 hours; after the reaction is completed, the modified tea polyphenols are obtained by purification and drying.

[0014] Preferably, the preparation method of functionalized nano-cerium dioxide is as follows: first, 10 parts of nano-cerium dioxide with a particle size of 10-30 nm are plasma-treated and then dispersed in 100 parts of anhydrous ethanol, and 0.8-1.2 parts of (3-aminopropyl)triethoxysilane are added; then, the mixture is heated to 78°C and reacted for 8 hours; the reaction product is purified by centrifugal washing; and finally, the functionalized nano-cerium dioxide is obtained by vacuum drying at 60°C for 12 hours.

[0015] Preferably, the plasma treatment conditions are: using a mixed gas of oxygen and argon in a volume ratio of 4:1 to pre-treat the nano-cerium dioxide powder with plasma at a power of 70-90 W and a pressure of 30 Pa for 4-6 minutes.

[0016] Preferably, the preparation method of silver-loaded nano-silica is as follows: 10 parts of nano-silica with a particle size of 30-60 nm are dispersed in ethanol, silver nitrate solution is first added for adsorption for 2 hours, and then 0.1 parts of sodium borohydride solution are added for reaction for 1 hour; the washed and dried silver-loaded silica is dispersed in 100 parts of anhydrous toluene, 1 part of (3-aminopropyl)triethoxysilane is added, and reflux reaction is carried out at 110° C. for 6 hours; the product is washed and purified and then vacuum-dried at 80° C. for 12 hours to obtain silver-loaded nano-silica; the silver nitrate solution is prepared by dissolving 0.15-0.25 parts of silver nitrate in 5 parts of deionized water.

[0017] On the other hand, the present invention provides an application method of UV resin coating: after coating, the wet film is leveled at room temperature for 5 minutes; then pre-baked at 60°C for 15 minutes, then UV cured, and finally the wood board is post-baked at 70-80°C for 60-90 minutes.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. In the present invention, by placing methacrylated tea polyphenols that can be covalently bonded during the UV curing stage in component A and combining them with silver-loaded nano-silica and nano-cerium dioxide in component B, effective synergy of organic and inorganic antibacterial components is achieved; nano-cerium dioxide provides an antioxidant microenvironment for silver ions due to its redox properties, prolonging the antibacterial activity, while methacrylated tea polyphenols also contribute to the antioxidant barrier; the dual curing process chemically bonds the organic and inorganic antibacterial units in the network in stages through UV light and thermal curing, fundamentally preventing the migration and loss of antibacterial components and significantly improving the long-term effectiveness and stability of the antibacterial performance.

[0020] 2. In the present invention, functionalized nano-cerium dioxide and silver-loaded nano-silicon dioxide are added to component B as synergistic wear-resistant fillers, and their physical properties are used to optimize micro-stacking and stress dispersion; the key is that the functional groups on the surfaces of the two fillers react with isocyanate during the thermal curing stage to form a strong chemical bond interface, effectively transferring stress to the hard filler and preventing it from falling off; combined with the hard surface layer formed by UV curing and the overall network and filler anchoring constructed by thermal curing, this highly integrated organic-inorganic structure significantly improves the wear resistance of the coating.

[0021] 3. In the present invention, fluorine-containing water-based polyurethane acrylate is introduced, and its fluorocarbon chain segments give the coating low surface energy to enhance hydrophobicity; the fluorine-containing resin and other components in the system form a dense cross-linked network through dual curing and chemically bonded and anchored functionalized inorganic fillers, which jointly construct an efficient physical barrier and tortuous penetration path, and eliminate interfacial water seepage channels; rapid UV curing fixes the surface fluorine chain segment orientation, and subsequent thermal curing improves the integrity of the bulk network, and finally combines low surface energy with a high-density structure to give the coating excellent water penetration resistance and long-term stability.

[0022] 4. In the present invention, a two-component system is mixed and then isocyanate is added, which overcomes the storage limitation of a single component and optimizes the resin ratio of component A; its dual curing process works synergistically, and the fluorinated polyurethane acrylate and the bonded methacrylated tea polyphenols are rapidly polymerized by UV curing to form a wear-resistant surface layer and fix the organic antibacterial agent; the subsequent mild thermal curing promotes the cross-linking of isocyanate with hydroxyl resin and surface functionalized inorganic filler, constructing a strong network throughout the whole and chemically anchoring the filler, thereby enhancing water resistance and chemical resistance, adhesion and pencil hardness, and the orderly curing reduces stress and improves the comprehensive protective performance of the coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the antibacterial rate of Escherichia coli in Examples 1-3 of the present invention and Comparative Examples 1-4. DETAILED DESCRIPTION

[0024] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] See also Figure 1 The present invention provides a preparation method and application of UV resin coating, and the technical solution is as follows:

[0026] Example 1

[0027] Preparation of Fluorinated Waterborne Polyurethane Acrylate Dispersion

[0028] A mixture of 55 parts of 2000 molecular weight polytetramethylene glycol, 15 parts of polycarbonate diol (Hubei Yamade CAS29862-10-0), 8 parts of 2000 molecular weight perfluoropolyether diol (Wuhan Kemik Biopharmaceutical Technology Co., Ltd.) and 4.5 parts of dihydroxymethylpropionic acid was heated to 80°C and vacuum treated at this temperature for 2 hours. The temperature was then lowered to 60°C, the vacuum operation was stopped, and nitrogen was introduced. 26.5 parts of isophorone diisocyanate (Covestro, Desmodur I), 30 parts of acetone, and 0.08 parts of dibutyltin dilaurate were added to the reactor, and the mixture was reacted at 75°C for 4 hours to obtain a prepolymer. Subsequently, 9 parts of hydroxyethyl acrylate were added and reacted at 60°C for 2 hours, and then 3.4 parts of triethylamine were added and reacted for 30 minutes. The obtained neutralized prepolymer solution was shear-dispersed in water at 1000 rpm. Finally, the mixture was distilled under reduced pressure at 50°C to obtain a fluorine-containing waterborne polyurethane acrylate dispersion with a solid content of 35%.

[0029] Preparation of modified tea polyphenols

[0030] Under nitrogen, 10 parts of tea polyphenols were dissolved in 100 parts of anhydrous acetone, and 12 parts of triethylamine were added. 16 parts of methacrylic anhydride was added at 5°C. The reaction was then carried out at 5°C for 12 hours, then the temperature was raised to 25°C and the reaction continued for 6 hours. After the reaction was completed, most of the acetone was removed using a rotary evaporator at a temperature below 40°C. The residue was dissolved in an appropriate amount of dichloromethane, washed three times with a saturated sodium chloride solution, and then washed twice with deionized water. The organic phase was collected and dried over anhydrous magnesium sulfate overnight. The desiccant was filtered off, and the filtrate was subjected to a rotary evaporator at a temperature below 40°C to remove dichloromethane. The purified product was dried under vacuum to obtain the modified tea polyphenol.

[0031] Preparation of functionalized nano-cerium dioxide

[0032] First, 10 parts of nano-cerium dioxide were plasma treated. The plasma treatment conditions were as follows: the nano-cerium dioxide powder was plasma pretreated for 4 minutes using a mixture of oxygen and argon in a volume ratio of 4:1 at 70W power and 30Pa pressure, and then dispersed in 100 parts of anhydrous ethanol, and 0.8 parts of (3-aminopropyl)triethoxysilane were added; then heated to the ethanol reflux temperature of 78°C for 8 hours; the reaction product was washed and purified; and finally, it was vacuum dried at 60°C for 12 hours to obtain functionalized nano-cerium dioxide.

[0033] Preparation of silver-loaded nanosilica

[0034] 10 parts of mesoporous silica were dispersed in ethanol, and a solution prepared by 0.15 parts of silver nitrate was added in sequence for adsorption for 2 hours, and then 0.1 parts of sodium borohydride was added dropwise for reaction for 1 hour; the washed and dried silver-loaded silica was dispersed in 100 parts of anhydrous toluene, and 1 part of (3-aminopropyl)triethoxysilane was added, and the mixture was refluxed at 110°C for 6 hours for amino functionalization; the product was washed and purified; and finally, it was vacuum dried at 80°C for 12 hours to obtain silver-loaded nano-silica.

[0035] Preparation of UV resin coating

[0036] Preparation of component A: 100 parts of fluorinated aqueous polyurethane acrylate dispersion and 45 parts of aqueous hydroxyl polyurethane dispersion (Guangzhou Huidigao Chemical Co., Ltd., DVK7856) were mixed evenly, and then 3.5 parts of dipropylene glycol dimethyl ether and 0.3 parts of polyurethane dispersant (Runfeng Synthetic Technology CAS34730-59-1) were added; then 2 parts of modified tea polyphenols and 0.1 parts of polymerization inhibitor (Mitsui Chemicals, hydroquinone monomethyl ether CAS150-76-5) were added; then 4 parts of composite photoinitiator were added; and finally, component A was obtained by filtration; the composite photoinitiator was obtained by mixing 1-hydroxycyclohexyl phenyl ketone and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide in a weight ratio of 1:1 and dissolving in dipropylene glycol dimethyl ether.

[0037] Preparation of component B: Mix 7 parts of dipropylene glycol dimethyl ether with 13 parts of deionized water; add 0.4 parts of wetting agent; then slowly add 4 parts of functionalized nano-cerium dioxide and 2 parts of silver-loaded nano-silica, and disperse at high speed for 20 minutes; then add 0.4 parts of leveling agent (Wuhan Runxingyuan Technology Co., Ltd., brand 6410), 0.2 parts of defoaming agent (Evonik Digo, model AIREX901W) and 1.1 parts of thickener (Tianchou Chemical, brand 935) in sequence; finally filter to obtain the component B premix.

[0038] The premix of component A and component B was mixed uniformly; then 16 parts of an isocyanate curing agent (Covestro, brand 401-60) was added; and stirring was continued for 5 minutes to obtain a UV resin coating.

[0039] After applying UV resin coating to the wood board, the wet film was leveled at room temperature for 5 minutes; then pre-baked at 60°C for 15 minutes; then UV-cured using a high-pressure mercury lamp with a light intensity of 100mW / cm² and an irradiation time of 12 seconds; finally, the wood board was post-baked at 70°C for 60 minutes.

[0040] The only difference between Example 2 and Example 1 is that: 18 parts of methacrylic anhydride are used in the preparation of modified tea polyphenols; 0.20 parts of silver nitrate are used in the preparation of silver-loaded nano-silicon dioxide; the added amount of modified tea polyphenols is 2.5 parts; and 2.5 parts of silver-loaded nano-silicon dioxide.

[0041] The only difference between Example 3 and Example 1 is that: 20 parts of methacrylic anhydride are used in the preparation of modified tea polyphenols; 0.25 parts of silver nitrate are used in the preparation of silver-loaded nano-silicon dioxide; the added amount of modified tea polyphenols is 3 parts; and the silver-loaded nano-silicon dioxide is 3 parts.

[0042] The only difference between Example 4 and Example 2 is that: in the preparation of functionalized nano-cerium dioxide, the nano-cerium dioxide is first plasma treated with a power of 80 W and a treatment time of 5 minutes, and then 1 part of (3-aminopropyl)triethoxysilane is added; in the preparation of component B, 5 parts of functionalized nano-cerium dioxide are added.

[0043] The only difference between Example 5 and Example 2 is that: in the preparation of functionalized nano-cerium dioxide, the nano-cerium dioxide is first plasma treated with a power of 90 W and a treatment time of 6 minutes, and then 1.2 parts of (3-aminopropyl)triethoxysilane are added; in the preparation of component B, 6 parts of functionalized nano-cerium dioxide are added.

[0044] The only difference between Example 6 and Example 4 is that in the preparation of the fluorine-containing aqueous polyurethane acrylate dispersion, 10 parts of perfluoropolyether diol and 27 parts of isophorone diisocyanate were added for reaction.

[0045] The only difference between Example 7 and Example 4 is that in the preparation of the fluorine-containing aqueous polyurethane acrylate dispersion, 12 parts of perfluoropolyether diol and 28 parts of isophorone diisocyanate were added for reaction.

[0046] The only difference between Example 8 and Example 6 is that: in the mixing step of coating preparation, 18 parts of isocyanate curing agent are added; in the preparation of component A, 50 parts of aqueous hydroxyl polyurethane dispersion are added; in the coating curing step, the post-baking temperature is set to 75°C and the post-baking time is set to 75 minutes.

[0047] The only difference between Example 9 and Example 6 is that: in the mixing step of coating preparation, 20 parts of isocyanate curing agent are added; in the preparation of component A, 55 parts of aqueous hydroxyl polyurethane dispersion are added; in the coating curing step, the post-baking temperature is set to 80°C and the post-baking time is set to 90 minutes.

[0048] The only difference between Comparative Example 1 and Example 1 is that the tea polyphenols are not modified.

[0049] The only difference between Comparative Example 2 and Example 1 is that no silver-loaded nano-silicon dioxide is added.

[0050] The only difference between Comparative Example 3 and Example 1 is that no modified tea polyphenols are added.

[0051] The only difference between Comparative Example 4 and Example 1 is that no modified tea polyphenols and no functionalized nano-cerium dioxide are added.

[0052] The only difference between Comparative Example 5 and Example 1 is that no functionalized nano-cerium dioxide is added.

[0053] The only difference between Comparative Example 6 and Example 1 is that the functionalized nano-cerium dioxide is not subjected to plasma treatment.

[0054] The only difference between Comparative Example 7 and Example 1 is that neither nano-cerium dioxide nor nano-silicon dioxide is treated with (3-aminopropyl)triethoxysilane.

[0055] Comparative Example 8 differs from Example 1 only in that no perfluoropolyether diol is added during the preparation of the fluorine-containing aqueous polyurethane acrylate dispersion.

[0056] Comparative Example 9 is different from Example 1 only in that in component A, an equal amount of fluorine-containing aqueous polyurethane acrylate dispersion is used to replace the aqueous hydroxyl polyurethane dispersion.

[0057] The only difference between Comparative Example 10 and Example 1 is that 1-hydroxycyclohexyl phenyl ketone is used as a single-component photoinitiator, and is not compounded with bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

[0058] The only difference between Comparative Example 11 and Example 1 is that after the UV resin coating is applied, only UV curing is performed without post-baking treatment.

[0059] The only difference between Comparative Example 12 and Example 1 is that after the UV resin coating is applied, only post-drying treatment is performed without UV curing.

[0060] Comparative Example 13 differs from Example 1 only in that: Component A and Component B are not distinguished, all raw materials of Component A and Component B are mixed at once to prepare a mixed coating, which is then mixed with isocyanate to prepare a UV resin coating.

[0061] Test Example 1

[0062] Test Subjects: Wood boards coated with the UV resin coatings prepared in Examples 1-3 and Comparative Examples 1-4 were aged. Aging conditions were as follows: The temperature was set at 50°C and the relative humidity was 60% in an artificial climate aging chamber. UV-A340 lamps were used to simulate UV exposure, with an irradiance of 0.76 W / m2. The operating mode adopted a cycle of 8 hours of illumination followed by 4 hours of condensation, repeated six times. The aged wood boards were then tested.

[0063] Test Method: Antibacterial performance testing was conducted in accordance with GB / T21866-2008, using Escherichia coli as the bacterial species. The final test results are shown in Table 1.

[0064] Table 1 Antibacterial performance test results

[0065] serial number Antibacterial rate of Escherichia coli (%) Example 1 90.2 Example 2 91.5 Example 3 91.8 Comparative Example 1 85.5 Comparative Example 2 74.0 Comparative Example 3 79.5 Comparative Example 4 66.2

[0066] Combined with Table 1 and Figure 1 It can be seen that in Comparative Example 1, since the tea polyphenols were not modified by methacrylate, they lacked reactive groups that could participate in UV-curing copolymerization, resulting in their inability to be firmly anchored in the polymer network through covalent bonds. Under aging conditions, they were easily migrated and lost, reducing the durability of the organic antibacterial component. In Comparative Example 2, silver-loaded nano-silica was not added, and the core inorganic silver ion antibacterial source was directly missing, making the system mainly dependent on organic antibacterial agents, reducing the overall antibacterial efficacy and long-term effectiveness. In Comparative Example 3, modified tea polyphenols were not added, and organic antibacterial units and their potential antioxidant synergistic effects were missing. It relied solely on inorganic antibacterial agents, narrowed the antibacterial spectrum, and lost the advantage of quickly fixing the antibacterial components on the surface during the UV-curing stage. In Comparative Example 4, both modified tea polyphenols and functionalized nano-cerium dioxide were missing. Not only was there no organic antibacterial and antioxidant supplementation, but more importantly, the antioxidant microenvironment provided by nano-cerium dioxide for silver ions was missing, making silver easily oxidized and inactivated during the aging process.

[0067] These comparative examples together reveal the synergistic mechanism and durability source of the antibacterial system of the present invention: Comparative Examples 1 and 3 illustrate that the introduction of organic antibacterial agents and chemical bonding fixation are indispensable, and the strategy of using methacrylated tea polyphenols and UV-curing anchoring is very important; Comparative Example 2 shows that inorganic silver ions are the key component for achieving strong antibacterial effects; the results of Comparative Example 4 are compared with Comparative Examples 1 and 3, highlighting the importance of the antioxidant protection of nano-cerium dioxide in maintaining the activity of silver ions and ensuring the durability of inorganic antibacterial agents, and at the same time confirming that the organic components also contribute to the synergistic design of the antioxidant barrier; these comparative examples prove from different angles that only the synergistic effect of organic and inorganic antibacterial units, and the use of a dual curing process to achieve a strong chemical bond between the two, can effectively overcome the limitations of a single antibacterial agent and the problem of oxidative inactivation, and achieve long-term and stable antibacterial performance.

[0068] Test Example 2

[0069] Test objects: Wood boards coated with UV resin coatings prepared in Examples 1-2, Examples 4-5 and Comparative Examples 2 and 5-8 were tested.

[0070] The final test results are shown in Table 2.

[0071] Table 2 Wear resistance test results

[0072] serial number Abrasion resistance (200g / 100r) / g Example 1 0.013 Example 2 0.011 Example 4 0.010 Example 5 0.009 Comparative Example 2 0.019 Comparative Example 5 0.018 Comparative Example 6 0.015 Comparative Example 7 0.016 Comparative Example 8 0.014

[0073] Comparative Example 2 lacks silver-loaded nano-silica, that is, it lacks the hard filler base of silica, which reduces the content and type of hard phase in the system and affects the synergistic reinforcement effect of the composite filler; Comparative Example 5 does not add functionalized nano-cerium dioxide, which also reduces a key hard inorganic filler, destroys the synergistic design of optimizing micro-stack and stress dispersion by compounding two different fillers, and reduces the overall wear resistance of the coating; in Comparative Example 6, nano-cerium dioxide is not plasma pretreated, resulting in insufficient surface active sites, which affects the subsequent grafting effect of aminosilane. rate, the strength of the chemical bond interface formed is weakened, which hinders stress transfer and reduces wear resistance; in Comparative Example 7, both inorganic fillers are not functionalized with aminosilane, and the ability to react with isocyanate to form covalent bond anchoring is completely lost. The fillers only play a physical filling role and are very easy to fall off under friction, resulting in a significant reduction in wear resistance; Comparative Example 8 lacks fluorine-containing components. Although it mainly affects water resistance, it changes the composition and network structure of the polymer matrix, which indirectly affects the toughness and surface friction coefficient of the coating, thereby causing a certain degree of negative effect on wear resistance.

[0074] The comparison of these comparative examples clearly demonstrates the synergistic mechanism of the present invention in improving the wear resistance: the results of comparative examples 2 and 5 show that the composite addition of two hard inorganic fillers with different properties is crucial for optimizing the microstructure and stress dispersion; the results of comparative examples 6 and 7 emphasize the core role of filler surface functionalization and chemical bonding anchoring. Plasma treatment optimizes the functionalization premise, and the grafting of aminosilane is the key to achieving a strong covalent bond with the matrix. Only by chemically bonding the filler to the network through thermal curing can the stress be effectively transferred and prevented from falling off, maximizing the advantages of the hard filler and achieving the purpose of significantly improving wear resistance and scratch resistance. Comparative example 8 suggests that the properties of the matrix resin itself will also affect the final wear resistance, and the synergistic effect of the entire system jointly contributes to the final wear resistance.

[0075] Test Example 3

[0076] Test objects: Wood boards coated with UV resin coatings prepared in Example 1, Examples 6-7, and Comparative Examples 8-9 were tested. The final test results are shown in Table 3.

[0077] Table 3 Water resistance test results

[0078] serial number Water resistance (48h) Example 1 No abnormalities Example 6 No abnormalities Example 7 No abnormalities Comparative Example 8 foaming Comparative Example 9 foaming

[0079] In Table 3, Comparative Example 8 did not add perfluoropolyether diol when making the homemade fluorine-containing water-based polyurethane acrylate. The core reason is that the fluorocarbon segment that gives the coating low surface energy and strong hydrophobicity is removed, which destroys the mechanism of using fluorine element to reduce water wettability, making the coating surface more easily wetted by water. At the same time, the changed polymer structure also affects the density of the network, resulting in a decrease in water resistance; Comparative Example 9 replaced the water-based hydroxyl polyurethane dispersion in component A with fluorine-containing polyurethane acrylate. The key is that the number of hydroxyl groups in the system that can participate in thermal curing cross-linking is greatly reduced, making it impossible for the isocyanate curing agent in component B to fully react and unable to form a complete, highly cross-linked polyurethane network structure, destroying the mechanism that the dense network structure provides a physical barrier and increases the difficulty of water molecules penetrating, resulting in a significant weakening of the water penetration resistance of the coating bulk structure.

[0080] These two comparative examples reveal the source of the excellent water resistance of the present invention from different levels: the result of comparative example 8 emphasizes the importance of chemical composition, that is, the low surface energy characteristics brought about by the introduction of fluorine-containing segments for achieving surface hydrophobicity; the result of comparative example 9 highlights the physical structure, that is, the key role of the highly cross-linked and dense network structure formed by dual curing in preventing bulk water penetration; the combination of the two shows that the water resistance of the present invention is the result of the synergistic effect of low surface energy chemical properties and high-density physical structure. At the same time, the chemical bonding anchoring of the functionalized filler also eliminates the interfacial water seepage channel, and together constructs an efficient waterproof barrier.

[0081] Test Example 4

[0082] Test objects: Wood boards coated with UV resin coatings prepared in Example 1, Examples 8-9 and Comparative Examples 9-13 were tested.

[0083] Test method: Refer to test examples 1-3. The final test results are shown in Table 4.

[0084] Table 4 Comprehensive performance test results

[0085] Performance indicators Example 1 Example 8 Example 9 Comparative Example 9 Comparative Example 10 Comparative Example 11 Comparative Example 12 Comparative Example 13 Antibacterial rate of Escherichia coli (%) 90.2 93.7 93.5 80.6 86.5 75.3 78.1 83.2 Abrasion resistance (200g / 100r) / g 0.013 0.008 0.008 0.017 0.015 0.020 0.018 0.016 Water resistance (48h) No abnormalities No abnormalities No abnormalities foaming No abnormalities foaming foaming foaming Adhesion, ≧ 1 1 1 3 1 3 2 2 Pencil hardness (2mm grid) / grade H 2H 2H B B B 2B B <![CDATA[Alkaline resistance (50 g / L NaHCO3, 1 h)]]> No abnormalities No abnormalities No abnormalities Slight loss of gloss No abnormalities corrosion corrosion Slight loss of gloss Alcohol resistance (50%, 1h) No abnormalities No abnormalities No abnormalities Slight loss of gloss No abnormalities corrosion corrosion Slight loss of gloss

[0086] In Table 4, Comparative Example 9 lacks sufficient hydroxyl groups to participate in thermal curing, resulting in an incomplete cross-linking network. Not only is the water resistance poor, but its insufficient degree of chemical bonding also affects chemical resistance and adhesion. Comparative Example 10 uses a single photoinitiator, resulting in insufficient or uneven UV curing, affecting the surface hardness, wear resistance, and fixation efficiency of the organic antimicrobial agent, weakening the synergistic effect of the UV curing step in the dual curing. Comparative Example 11 omits thermal curing, completely lacking the bulk polyurethane cross-linking network and chemical anchoring of the inorganic filler, resulting in a complete loss of properties that rely on the bulk structure, such as water resistance, chemical resistance, and adhesion. Comparative Example 12 omits UV curing, and a fast-curing hard surface layer cannot be formed, resulting in poor wear resistance, and the organic antimicrobial agent fails to covalently bond, affecting its durability. Comparative Example 13 uses one-time mixing, which destroys the premise of finely controlling dispersion and reaction of the two-component system, resulting in uneven component dispersion, compatibility issues, or incomplete reaction, forming a defective coating film, making it difficult to achieve optimized levels of various performance indicators.

[0087] These comparative examples verify the mechanism of comprehensive performance improvement of the present invention from the perspectives of system composition, curing process and operation flow: Comparative Example 9 shows the importance of precise stoichiometric ratio for building a complete network; Comparative Example 10 emphasizes the role of optimizing the photoinitiator system in UV curing efficiency; the results of Comparative Examples 11 and 12 fully demonstrate that the dual mechanisms of UV curing and thermal curing are indispensable, and the two work synergistically in time and function, contributing to the key properties of the surface and bulk phase respectively, achieving performance complementarity; Comparative Example 13 illustrates that the use of two components and a prescribed preparation and mixing process is a necessary process guarantee to ensure effective synergy of the components, avoid adverse reactions, and achieve ultimate high performance, reflecting the systematic advantages of the overall formula and process design.

[0088] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a UV resin coating, characterized in that: The UV resin coating is prepared by: uniformly mixing the premix of component A and component B; then adding 16-20 parts of an isocyanate curing agent; Continue stirring and mixing to obtain the UV resin coating; Preparation of the A component: 100 parts of a fluorine-containing aqueous polyurethane acrylate dispersion and 45-55 parts of an aqueous hydroxyl polyurethane dispersion are uniformly mixed, and then dipropylene glycol dimethyl ether and a polyurethane dispersant, 2-3 parts of methacrylated tea polyphenols, a polymerization inhibitor, and 4 parts of a composite photoinitiator are sequentially added, and finally filtered to obtain the A component; Preparation of the B component: 7 parts of dipropylene glycol dimethyl ether and 13 parts of deionized water are mixed; a wetting agent is added; then 4-6 parts of functionalized nano-cerium dioxide and 2-3 parts of silver-loaded nano-silicon dioxide are slowly added, and high-speed dispersion is performed for 20 minutes; then a leveling agent, a defoaming agent and a thickener are sequentially added; and finally, the B component is filtered to obtain the B component.

2. The method for preparing a UV resin coating according to claim 1, wherein: The composite photoinitiator is prepared by mixing 1-hydroxycyclohexyl phenyl ketone and bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide in a weight ratio of 1-2:1 and then dissolving the mixture in dipropylene glycol dimethyl ether.

3. The method for preparing a UV resin coating according to claim 1, wherein: The preparation method of the fluorine-containing waterborne polyurethane acrylate dispersion comprises the following steps: dehydrating a mixture of 55 parts of polytetramethylene glycol, 15 parts of polycarbonate diol, 8-12 parts of perfluoropolyether diol and 4.5 parts of dihydroxymethyl propionic acid; subsequently adding 26-28 parts of isophorone diisocyanate, 30 parts of acetone and 0.08 parts of dibutyltin dilaurate, and reacting at 75°C for 4 hours to obtain a prepolymer; after the reaction is completed, lowering the system temperature to 60°C, adding 9 parts of hydroxyethyl acrylate and reacting for 2 hours; then adding 3.4 parts of triethylamine and reacting for 30 minutes, and dispersing the obtained neutralized prepolymer solution in water under high shear force; and finally, distilling under reduced pressure at 50°C to obtain the fluorine-containing waterborne polyurethane acrylate dispersion with a solid content of 35%.

4. The method for preparing a UV resin coating according to claim 1, wherein: The preparation method of the methacrylated tea polyphenol is as follows: under nitrogen protection, 10 parts of tea polyphenol are dissolved in 100 parts of anhydrous acetone, and 12 parts of triethylamine are added; 16-20 parts of methacrylic anhydride are added at 5°C; then, the mixture is reacted at 5°C for 12 hours and the temperature is raised to 25°C and the reaction is continued for 6 hours to complete the esterification; after the reaction is completed, the methacrylated tea polyphenol is obtained by purification and drying.

5. The method for preparing a UV resin coating according to claim 1, wherein: The preparation method of the functionalized nano-cerium dioxide is as follows: first, 10 parts of nano-cerium dioxide are subjected to plasma treatment and then dispersed in 100 parts of anhydrous ethanol, and 0.8-1.2 parts of (3-aminopropyl)triethoxysilane are added; then, the mixture is heated to 78° C. and reacted for 8 hours; the reaction product is purified by centrifugal washing; and finally, the functionalized nano-cerium dioxide is obtained by vacuum drying at 60° C. for 12 hours.

6. The method for preparing a UV resin coating according to claim 5, wherein: The plasma treatment conditions are as follows: using a mixed gas of oxygen and argon with a volume ratio of 4:1 to pre-treat the nano-cerium dioxide powder with plasma at a power of 70-90W and a pressure of 30Pa for 4-6 minutes.

7. The method for preparing a UV resin coating according to claim 1, wherein: The preparation method of the silver-loaded nano-silica comprises the following steps: dispersing 10 parts of nano-silica in ethanol, first adding a solution prepared from 0.15-0.25 parts of silver nitrate for adsorption for 2 hours, then adding 0.1 parts of sodium borohydride for reaction for 1 hour; dispersing the washed and dried silver-loaded silica in 100 parts of anhydrous toluene, adding 1 part of (3-aminopropyl)triethoxysilane, and reacting at reflux at 110° C. for 6 hours; and finally, centrifugally washing and purifying the product and vacuum drying it at 80° C. for 12 hours to obtain the silver-loaded nano-silica.

8. An application of the UV resin coating prepared by the preparation method according to claim 1, characterized in that: After the UV resin coating is applied to the wood board, it is pre-baked at 60° C. for 15 minutes, then UV-cured, and finally the wood board is post-baked at 70-80° C. for 60-90 minutes.

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