Preparation method and application of UV resin coating

Abstract

The invention relates to the technical field of coatings, in particular to a preparation method and application of a UV resin coating. According to the invention, the defects of poor wear resistance and poor antibacterial property of the existing UV resin coating in woodware application are overcome. The preparation method comprises the following steps: preparing a component A by taking a fluorine-containing waterborne polyurethane acrylate dispersion, waterborne hydroxyl polyurethane, modified tea polyphenol, a polymerization inhibitor and the like as raw materials; functional nano cerium dioxide, silver-loaded nano silicon dioxide, a flatting agent, a composite photoinitiator and the like are used as raw materials to prepare a component B; and finally, mixing the component A, the component B and an isocyanate curing agent to obtain the UV resin coating. The fluorine-containing waterborne polyurethane acrylate dispersoid is prepared by taking polytetrahydrofuran glycol, polycarbonate diol, perfluoropolyether glycol and the like as raw materials; the modified tea polyphenol is prepared by taking tea polyphenol and methacrylic anhydride as raw materials. The prepared UV resin coating is a water-based UV resin coating, is suitable for wood floors, and has the advantages of improving wear resistance and antibacterial property.

Description

Technical Field

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

[0002] With the continuous improvement of people's requirements for the quality of the home environment, wooden floors are highly favored by many families due to the warm atmosphere created by their unique natural textures and the gentle foot feeling when stepped on. In the field of home decoration wooden floors, waterborne UV resins have significant advantages over traditional UV resins. Waterborne UV resins use water as the dispersion medium, and have characteristics such as low VOC emissions, environmental protection and safety, greatly reducing indoor air pollution and meeting the pursuit of modern families for a healthy living environment.

[0003] Waterborne UV resin coatings can be divided into various types according to the resin type, among which waterborne polyurethane acrylate resins are widely used. When waterborne polyurethane acrylate resins are used for wooden floors, they exhibit many advantages, such as good flexibility and adhesion, being able to adapt to the minor deformations of wooden floors due to environmental changes, not being easily cracked or peeled off, and the coatings formed after their curing having certain wear resistance and water resistance, which can effectively protect the wooden floors.

[0004] However, when laying wooden floors in families with pets or children, the floors face severe challenges. The scratching of pets' claws and the daily activities of children require extremely high wear resistance of the floors. At the same time, pet hair, excrement, and germs carried during children's play make the antibacterial performance of the floors crucial. Although existing waterborne polyurethane acrylate resins have certain wear resistance, they are still prone to scratches in the face of long-term and frequent scratching by pets and high-intensity use scenarios by children, affecting the aesthetics and service life; in terms of antibacterial properties, their antibacterial ability is limited, and it is difficult to effectively inhibit the growth of various bacteria, unable to fully guarantee the family's health 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 requirements of such families for wooden floor coatings and provide a better, more durable and healthy floor protection solution for families.

[0005] For this reason, a preparation method and application of a UV resin coating are proposed. Summary of the Invention

[0006] The object of the present invention is to provide a preparation method and application of a UV resin coating. The present invention uses a fluorinated waterborne polyurethane acrylate dispersion, a waterborne hydroxyl polyurethane, a modified tea polyphenol, a polymerization inhibitor, etc. as raw materials to prepare component A; uses functionalized nano-ceria, silver-loaded nano-silica, a leveling agent, a composite photoinitiator, etc. as raw materials to prepare component B; finally mixes component A, component B with an isocyanate curing agent to obtain a UV resin coating; the fluorinated waterborne polyurethane acrylate dispersion is prepared using polytetrahydrofuran diol, polycarbonate diol, perfluoropolyether diol, etc. as raw materials; the modified tea polyphenol is prepared using tea polyphenol and methacrylic anhydride as raw materials. The UV resin coating prepared by the present invention is a waterborne UV resin coating, which is suitable for coating wooden floors and has the advantages of improving wear resistance and antibacterial properties.

[0007] To achieve the above object, the present invention provides the following technical solutions: On the one hand, the present invention provides a preparation method of a UV resin coating. By weight, the preparation method of the UV resin coating is: premix component A and component B premix evenly; then add 16 - 20 parts of an isocyanate curing agent; continue to stir for 5 min to obtain a UV resin coating; Preparation of component A: Mix 100 parts of a fluorinated waterborne polyurethane acrylate dispersion and 45 - 55 parts of a waterborne hydroxyl polyurethane dispersion evenly, then successively add dipropylene glycol dimethyl ether and a polyurethane-based dispersant, 2 - 3 parts of a modified tea polyphenol, a polymerization inhibitor, 4 parts of a composite photoinitiator, and finally filter to obtain component A; Preparation of component B: Mix 7 parts of dipropylene glycol dimethyl ether and 13 parts of deionized water; add 0.4 part of a wetting agent; then slowly add 4 - 6 parts of functionalized nano-ceria, 2 - 3 parts of silver-loaded nano-silica, and disperse at high speed for 20 min; then successively add 0.4 part of a leveling agent, 0.2 part of an antifoaming agent and 1.1 part of a thickening agent; finally filter to obtain a component B premix.

[0008] Preferably, the composite photoinitiator is obtained by mixing 1-hydroxycyclohexyl phenyl ketone and bis(2,4,6-trimethylbenzoyl) phenyl phosphine oxide in a weight ratio of 1:1 and dissolving them in dipropylene glycol dimethyl ether.

[0009] Preferably, the preparation method of the fluorinated aqueous polyurethane acrylate dispersion is as follows: dehydrate a mixture of 55 parts of polytetrahydrofuran diol, 15 parts of polycarbonate diol, 8 - 12 parts of perfluoropolyether diol and 4.5 parts of dimethylolpropionic acid; then add 26 - 28 parts of isophorone diisocyanate, 30 parts of acetone, and 0.08 part of dibutyltin dilaurate, and react at 75 °C for 4 h to obtain a prepolymer; after the reaction is completed, lower the temperature of the system to 60 °C, add 9 parts of hydroxyethyl acrylate and react for 2 h; then add 3.4 parts of triethylamine and react for 30 min, and disperse the obtained neutralized prepolymer solution in water under high shear force; finally, carry out vacuum distillation at 50 °C to obtain a fluorinated aqueous polyurethane acrylate dispersion with a solid content of 35%. Among them, the molecular weight of the polycarbonate diol is 1000 - 2000, and the molecular weight of the perfluoropolyether diol is 1000 - 2000.

[0010] Preferably, the preparation method of the modified tea polyphenols is as follows: under nitrogen protection, dissolve 10 parts of tea polyphenols in 100 parts of anhydrous acetone, and add 12 parts of triethylamine; add 16 - 20 parts of methacrylic anhydride at 5 °C; then react at 5 °C for 12 h and then raise the temperature to 25 °C and continue to react for 6 h; after the reaction is completed, obtain the modified tea polyphenols through purification and drying.

[0011] Preferably, the preparation method of the functionalized nano - cerium dioxide is as follows: first, perform plasma treatment on 10 parts of nano - cerium dioxide with a particle size of 10 - 30 nm and disperse it in 100 parts of anhydrous ethanol, then add 0.8 - 1.2 parts of (3 - aminopropyl)triethoxysilane; then heat to 78 °C and react for 8 h; the reaction product is centrifuged, washed, and purified; finally, vacuum - dry at 60 °C for 12 h to obtain the functionalized nano - cerium dioxide.

[0012] Preferably, the plasma treatment conditions are as follows: use a mixed gas of oxygen and argon with a volume ratio of 4:1 for the nano - cerium dioxide powder, and carry out plasma pretreatment at a power of 70 - 90 W and a pressure of 30 Pa for 4 - 6 min.

[0013] Preferably, the preparation method of the silver - loaded nano - silica is as follows: disperse 10 parts of nano - silica with a particle size of 30 - 60 nm in ethanol, first add a silver nitrate solution and adsorb for 2 h, then add 0.1 part of a sodium borohydride solution and react for 1 h; disperse the washed and dried silver - loaded silica in 100 parts of anhydrous toluene, add 1 part of (3 - aminopropyl)triethoxysilane, and reflux and react at 110 °C for 6 h; the product is washed, purified, and then vacuum - dried at 80 °C for 12 h to obtain the 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.

[0014] On the other hand, the present invention provides an application method for a 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, followed by UV curing, and finally the wooden board is post-baked at 70 - 80 °C for 60 - 90 minutes.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. In the present invention, by placing methacrylated tea polyphenols that can be covalently bonded in the UV curing stage in component A, and combining silver-loaded nano-silica and nano-ceria placed in component B, effective synergy between organic and inorganic antibacterial components is achieved; nano-ceria provides an antioxidant microenvironment for silver ions by virtue of its redox properties, extending the antibacterial activity, while methacrylated tea polyphenols also contribute an antioxidant barrier; the dual-curing process chemically bonds organic and inorganic antibacterial units to the network in stages through UV light and thermal curing, fundamentally preventing the migration and loss of antibacterial components, and significantly enhancing the long-term effectiveness and stability of the antibacterial performance.

[0016] 2. In the present invention, functionalized nano-ceria and silver-loaded nano-silica are compounded and added in component B as synergistic wear-resistant fillers, and their physical properties are used to optimize the micro-packing and stress dispersion; the key lies in the fact that the functional groups on the surfaces of the two fillers react with isocyanates in the thermal curing stage to form a firm chemical bond interface combination, effectively transferring stress to the hard fillers and preventing their detachment; combined with the hard surface layer formed by UV curing, the overall network constructed by thermal curing, and the anchoring of the fillers, this highly integrated organic-inorganic structure significantly improves the wear resistance of the coating.

[0017] 3. In the present invention, fluorinated waterborne polyurethane acrylate is introduced, and its fluorocarbon chain segments endow the coating with low surface energy to enhance hydrophobicity; the fluorinated resin, together with the dense cross-linked network formed by dual curing with other components in the system and the functionalized inorganic fillers anchored by chemical bonds, jointly constructs an efficient physical barrier and tortuous penetration path, and eliminates the interface water seepage channels; rapid UV curing fixes the orientation of the surface fluorine chain segments, and subsequent thermal curing improves the integrity of the bulk phase network. Finally, combined with low surface energy and high density structure, the coating is endowed with excellent water penetration resistance and long-term stability.

[0018] 4. In the present invention, a two-component system is mixed and then isocyanate is added, which overcomes the storage limitation of the single-component system and optimizes the resin ratio of component A; the dual-curing process has a synergistic effect. Through ultraviolet curing, fluorinated polyurethane acrylate and bonded methacrylated tea polyphenols are rapidly polymerized to form a wear-resistant surface layer and fix the organic antibacterial agent; subsequent mild thermal curing promotes the crosslinking of isocyanate with hydroxyl resin and surface-functionalized inorganic fillers, constructs a tough network throughout the whole and chemically anchors the fillers, thereby enhancing water and chemical resistance, adhesion and pencil hardness, and the orderly curing reduces stress and improves the comprehensive protection performance of the coating. Description of the Drawings

[0019] Figure 1 It is a schematic diagram of the antibacterial rate of Escherichia coli in Examples 1-3 and Comparative Examples 1-4 of the present invention. Detailed Embodiments

[0020] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0021] Please refer to Figure 1 , the present invention provides a preparation method and application of a UV resin coating, and the technical solutions are as follows: Example 1 Preparation of fluorinated aqueous polyurethane acrylate dispersion A mixture of 55 parts of polytetrahydrofuran diol with a molecular weight of 2000, 15 parts of polycarbonate diol (Hubei Yamade CAS 29862-10-0), 8 parts of perfluoropolyether diol with a molecular weight of 2000 (Wuhan Kemike Biopharmaceutical Technology Co., Ltd.) and 4.5 parts of dimethylolpropionic acid is heated to 80 °C, and the reaction system is evacuated for 2 hours at this temperature. Subsequently, the temperature is lowered to 60 °C, the vacuum operation is stopped, and nitrogen is introduced. 26.5 parts of isophorone diisocyanate (Covestro, Desmodur I), 30 parts of acetone, and 0.08 parts of dibutyltin dilaurate are added to the reaction kettle, and the reaction is carried out at 75 °C for 4 h to obtain a prepolymer; then 9 parts of hydroxyethyl acrylate are added and the reaction is carried out at 60 °C for 2 h, and then 3.4 parts of triethylamine are added and the reaction is carried out for 30 min; the obtained neutralized prepolymer solution is shear-dispersed in water at 1000 rpm; finally, it is distilled under reduced pressure at 50 °C to obtain a fluorinated aqueous polyurethane acrylate dispersion with a solid content of 35%.

[0022] Preparation of modified tea polyphenols Under nitrogen protection, 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 were added at 5 °C; then, after reacting at 5 °C for 12 h, the temperature was raised to 25 °C and the reaction continued for 6 h; after the reaction ended, most of the acetone was removed by a rotary evaporator under the condition of less than 40 °C. The residue was dissolved in an appropriate amount of dichloromethane, washed three times with saturated sodium chloride aqueous solution in sequence, and then washed twice with deionized water. The organic phase was collected and dried overnight with anhydrous magnesium sulfate. The desiccant was removed by filtration, and the filtrate was concentrated to remove dichloromethane by a rotary evaporator under the condition of less than 40 °C. The purified product was dried under vacuum to obtain the modified tea polyphenols.

[0023] Preparation of Functionalized Nano-Ceria First, 10 parts of nano-ceria were subjected to plasma treatment. The plasma treatment conditions were as follows: The nano-ceria powder was pretreated with a mixed gas of oxygen and argon with a volume ratio of 4:1 for 4 min under the conditions of 70 W power and 30 Pa pressure, and then dispersed in 100 parts of absolute ethanol. 0.8 part of (3-aminopropyl)triethoxysilane was added; then it was heated to the ethanol reflux temperature of 78 °C and reacted for 8 h; the reaction product was washed and purified; finally, it was dried in vacuum at 60 °C for 12 h to obtain functionalized nano-ceria.

[0024] Preparation of Silver-Loaded Nano-Silica 10 parts of mesoporous silica were dispersed in ethanol. A solution prepared from 0.15 part of silver nitrate was added and adsorbed for 2 h, and then 0.1 part of sodium borohydride was added and reacted for 1 h; 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 reaction was refluxed at 110 °C for 6 h for amino-functionalization; the product was washed and purified; finally, it was dried in vacuum at 80 °C for 12 h to obtain silver-loaded nano-silica.

[0025] Preparation of UV Resin Coating Preparation of Component A: 100 parts of fluorinated waterborne polyurethane acrylate dispersion was mixed evenly with 45 parts of waterborne hydroxyl polyurethane dispersion (Guangzhou Huidi High Chemical Co., Ltd., DVK7856), and then 3.5 parts of dipropylene glycol dimethyl ether and 0.3 part of polyurethane dispersant (Runfeng Synthetic Technology CAS34730-59-1) were added; then 2 parts of modified tea polyphenols and 0.1 part of inhibitor (Mitsui Chemicals, hydroquinone monomethyl ether CAS150-76-5) were added; then 4 parts of composite photoinitiator were added; finally, Component A was obtained by filtration; the composite photoinitiator was obtained by mixing 1-hydroxycyclohexyl phenyl ketone and bis(2,4,6-trimethylbenzoyl)phenyl phosphine oxide in a weight ratio of 1:1 and dissolving them in dipropylene glycol dimethyl ether.

[0026] Preparation of Component B: Mix 7 parts of dipropylene glycol dimethyl ether with 13 parts of deionized water; add 0.4 part of wetting agent; then slowly add 4 parts of functionalized nano-ceria and 2 parts of silver-loaded nano-silica, and disperse at high speed for 20 min; then add 0.4 part of leveling agent (Wuhan Runxingyuan Technology Co., Ltd., brand 6410), 0.2 part of defoaming agent (Evonik Degussa, model AIREX901W) and 1.1 part of thickening agent (Tianchou Chemical Industry, brand 935) in sequence; finally, filter to obtain the premix of Component B.

[0027] Mix Component A and the premix of Component B evenly; then add 16 parts of isocyanate curing agent (Covestro, brand 401-60); continuously stir for 5 min to obtain the UV resin coating.

[0028] Coat the UV resin coating on the wooden board, and let the wet film level at room temperature for 5 min; then pre-bake at 60 °C for 15 min; immediately cure with ultraviolet light using a high-pressure mercury lamp, with a light intensity of 100 mW / cm² and an irradiation time of 12 s; finally, post-bake the wooden board at 70 °C for 60 min.

[0029] The difference between Example 2 and Example 1 is only that: in the preparation of modified tea polyphenols, 18 parts of methacrylic anhydride are used; in the preparation of silver-loaded nano-silica, 0.20 part of silver nitrate is used; the addition amount of modified tea polyphenols is 2.5 parts; 2.5 parts of silver-loaded nano-silica.

[0030] The difference between Example 3 and Example 1 is only that: in the preparation of modified tea polyphenols, 20 parts of methacrylic anhydride are used; in the preparation of silver-loaded nano-silica, 0.25 part of silver nitrate is used; the addition amount of modified tea polyphenols is 3 parts; 3 parts of silver-loaded nano-silica.

[0031] The difference between Example 4 and Example 2 is only that: in the preparation of functionalized nano-ceria, first perform plasma treatment on nano-ceria with a power of 80 W and a treatment time of 5 min, then add 1 part of (3-aminopropyl)triethoxysilane; in the preparation of Component B, add 5 parts of functionalized nano-ceria.

[0032] The difference between Example 5 and Example 2 is only that: in the preparation of functionalized nano-ceria, first perform plasma treatment on nano-ceria with a power of 90 W and a treatment time of 6 min, then add 1.2 parts of (3-aminopropyl)triethoxysilane; in the preparation of Component B, add 6 parts of functionalized nano-ceria.

[0033] The difference between Example 6 and Example 4 is only that: in the preparation of fluorinated waterborne polyurethane acrylate dispersion, add 10 parts of perfluoropolyether diol and 27 parts of isophorone diisocyanate for reaction.

[0034] Example 7 is only different from Example 4 in that in the preparation of the fluorinated aqueous polyurethane acrylate dispersion, 12 parts of perfluoropolyether diol and 28 parts of isophorone diisocyanate are added for reaction.

[0035] Example 8 is only different from Example 6 in that in the mixing step of the 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 at 75 °C and the post-baking time is set at 75 min.

[0036] Example 9 is only different from Example 6 in that in the mixing step of the 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 at 80 °C and the post-baking time is set at 90 min.

[0037] Comparative Example 1 is only different from Example 1 in that tea polyphenols are not modified.

[0038] Comparative Example 2 is only different from Example 1 in that silver-loaded nano-silica is not added.

[0039] Comparative Example 3 is only different from Example 1 in that modified tea polyphenols are not added.

[0040] Comparative Example 4 is only different from Example 1 in that neither modified tea polyphenols nor functionalized nano-ceria are added.

[0041] Comparative Example 5 is only different from Example 1 in that functionalized nano-ceria is not added.

[0042] Comparative Example 6 is only different from Example 1 in that functionalized nano-ceria is not subjected to plasma treatment.

[0043] Comparative Example 7 is only different from Example 1 in that neither nano-ceria nor nano-silica is treated with (3-aminopropyl)triethoxysilane.

[0044] Comparative Example 8 is only different from Example 1 in that perfluoropolyether diol is not added during the preparation of the fluorinated aqueous polyurethane acrylate dispersion.

[0045] Comparative Example 9 is only different from Example 1 in that in Component A, the aqueous hydroxyl polyurethane dispersion is replaced with an equal amount of fluorinated aqueous polyurethane acrylate dispersion.

[0046] Comparative Example 10 is only different from Example 1 in that 1-hydroxycyclohexyl phenyl ketone is used as a single-component photoinitiator and is not compounded with bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide.

[0047] Comparative Example 11 is different from Example 1 only in that: after coating with the UV resin coating, only UV curing is carried out, and no post-drying treatment is performed.

[0048] Comparative Example 12 is different from Example 1 only in that: after coating with the UV resin coating, only post-drying treatment is carried out, and no UV curing is performed.

[0049] Comparative Example 13 is different from Example 1 only in that: without distinguishing between Component A and Component B, all raw materials of Component A and Component B are mixed at one time to prepare a mixed coating, and then mixed with isocyanate to prepare a UV resin coating.

[0050] Test Example 1 Test object: The wooden boards coated with the UV resin coatings prepared in Examples 1-3 and Comparative Examples 1-4 were subjected to aging treatment. The aging treatment conditions were: the temperature was set at 50 °C and the relative humidity was 60% in an artificial climate aging chamber. The UV-A340 lamp tube was selected to simulate ultraviolet irradiation, and its irradiance was set at 0.76 W / ㎡. The operation mode adopted a cycle of 8 hours of light and 4 hours of condensation, and the cycle was repeated 6 times; the aged wooden boards were tested.

[0051] Test method: The antibacterial performance test was carried out with reference to GB / T21866-2008, and the strain Escherichia coli was selected. The final test results are shown in Table 1.

[0052] Table 1 Antibacterial performance test result table Number Antibacterial rate against 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 Combined with Table 1 and Figure 1 It can be seen that in Comparative Example 1, since the tea polyphenols were not subjected to methacrylation modification, the reactive groups that could participate in the UV curing copolymerization were lacking, resulting in its inability to be firmly anchored in the polymer network by covalent bonds, being easily migrated and lost under aging conditions, and reducing the persistence of the organic antibacterial component; in Comparative Example 2, silver-loaded nano-silica was not added, directly lacking the core inorganic silver ion antibacterial source, making the system mainly rely on organic antibacterial agents, reducing the overall antibacterial efficacy and long-term effectiveness; in Comparative Example 3, modified tea polyphenols were not added, lacking the organic antibacterial unit and its potential antioxidant synergistic effect, relying only on inorganic antibacterial agents, resulting in a narrower antibacterial spectrum and losing the advantage of quickly fixing the antibacterial component on the surface during the UV curing stage; in Comparative Example 4, both modified tea polyphenols and functionalized nano-ceria were lacking, not only without organic antibacterial and antioxidant supplementation, but more importantly, lacking the antioxidant microenvironment provided by nano-ceria for silver ions, making silver easily oxidized and inactivated during the aging process.

[0053] 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 and chemical bonding fixation of the organic antibacterial agent are both indispensable, and the strategy of using methacrylated tea polyphenols and ultraviolet curing for anchoring is very important; Comparative Example 2 shows that inorganic silver ions are the key components to achieve strong antibacterial properties; comparing the results of Comparative Example 4 with those of Comparative Examples 1 and 3 highlights the importance of the antioxidant protection of nano-ceria for maintaining the activity of silver ions and ensuring the durability of inorganic antibacterial agents, and at the same time verifies the synergistic design in which the organic component also contributes to the antioxidant barrier; these comparative examples prove from different perspectives that only through the synergistic effect of organic and inorganic antibacterial units and the use of a dual-curing process to achieve strong chemical bonding between the two can effectively overcome the limitations and oxidative inactivation problems of single antibacterial agents and achieve long-term and stable antibacterial performance.

[0054] Test Example 2 Test objects: The wooden boards coated with the UV resin coatings prepared in Examples 1-2, Examples 4-5, Comparative Example 2, and Comparative Examples 5-8 were tested.

[0055] The final test results are shown in Table 2.

[0056] Table 2 Abrasion Resistance Test Results Table 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 Comparative Example 2 lacks silver-loaded nano-silica, that is, it lacks the hard filler substrate of silica, reducing the content and types of hard phases in the system and affecting the synergistic reinforcement effect of the composite filler; Comparative Example 5 does not add functionalized nano-ceria, also reducing a key hard inorganic filler, destroying the synergistic design of optimizing the micro-packing and stress dispersion through the combination of two different fillers, and reducing the overall abrasion resistance of the coating; in Comparative Example 6, the nano-ceria was not pretreated by plasma, resulting in insufficient surface active sites, affecting the grafting efficiency of subsequent amino-silane, weakening the chemical bond interface bonding strength formed, blocking stress transfer, and reducing abrasion resistance; in Comparative Example 7, neither of the two inorganic fillers was functionalized with amino-silane, completely lacking the ability to form covalent bonds and anchor with isocyanate, and the filler only plays a physical filling role and is extremely easy to fall off under friction, resulting in a significant reduction in abrasion 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, indirectly affecting the toughness and surface friction coefficient of the coating, thus having a certain negative effect on abrasion resistance.

[0057] The comparison of these comparative examples clearly demonstrates the synergistic mechanism for improving the wear resistance of the present invention: the results of Comparative Examples 2 and 5 illustrate 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 surface functionalization and chemical bonding anchoring of the fillers. Plasma treatment optimizes the premise of functionalization, while the grafting of amino silane is the key to achieving strong covalent bonding with the matrix. Only by chemically bonding the fillers into the network through thermal curing can stress be effectively transmitted and shedding be prevented, maximizing the advantages of the hard fillers and achieving a significant improvement in wear and scratch resistance; the result of Comparative Example 8 indicates that the characteristics of the matrix resin itself also affect the final wear resistance, and the synergistic effect of the entire system jointly contributes to the final wear resistance.

[0058] Test Example 3 Test object: The wooden boards coated with the 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.

[0059] Table 3 Water Resistance Test Results Table Number Water resistance (48h) Example 1 No abnormality Example 6 No abnormality Example 7 No abnormality Comparative Example 8 Foaming Comparative Example 9 Foaming In Table 3, in Comparative Example 8, perfluoropolyether diol was not added when preparing the self-made fluorinated waterborne polyurethane acrylate. The core lies in removing the fluorocarbon chain segments that endow the coating with low surface energy and strong hydrophobicity, destroying the mechanism of using fluorine elements to reduce water wettability, making the coating surface more easily wetted by water. At the same time, the changed polymer structure also affects the denseness of the network, resulting in a decrease in water resistance; in Comparative Example 9, the waterborne hydroxyl polyurethane dispersion in Component A was replaced with fluorinated polyurethane acrylate. The key lies in significantly reducing the number of hydroxyl groups that can participate in thermal curing crosslinking in the system, making the isocyanate curing agent in Component B unable to fully react and unable to form a complete, highly crosslinked polyurethane network structure, destroying the mechanism of the dense network structure providing a physical barrier and increasing the difficulty of water molecule penetration, resulting in a significant weakening of the water penetration resistance of the coating bulk structure.

[0060] These two comparative examples reveal the sources of the excellent water resistance of the present invention from different aspects: the result of Comparative Example 8 emphasizes the chemical composition, that is, the importance of the low surface energy characteristics brought by the introduction of fluorinated chain segments for achieving surface hydrophobicity; the result of Comparative Example 9 highlights the physical structure, that is, the key role of the highly crosslinked 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 characteristics and high dense physical structure. At the same time, the chemical bonding anchoring of functionalized fillers also eliminates the interfacial water seepage channels, jointly constructing an efficient waterproof barrier.

[0061] Test Example 4 Test object: The wooden boards coated with the UV resin coatings prepared in Example 1, Examples 8 - 9 and Comparative Examples 9 - 13 were tested.

[0062] Test method: Refer to Test Examples 1 - 3. The final test results are shown in Table 4.

[0063] Table 4 Comprehensive performance test results 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 against 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 abnormality No abnormality No abnormality Foaming No abnormality Foaming Foaming Foaming Adhesion, ≧ 1 1 1 3 1 3 2 2 Pencil hardness (cross-cut 2mm) / grade H 2H 2H B B B 2B B <![CDATA[Alkali resistance (50 g / L NaHCO3, 1 h)]]> No abnormality No abnormality No abnormality Slight loss of gloss No abnormality Corrosion Corrosion Slight loss of gloss Alcohol resistance (50%, 1h) No abnormality No abnormality No abnormality Slight loss of gloss No abnormality Corrosion Corrosion Slight loss of gloss In Table 4, in Comparative Example 9, due to the lack of sufficient hydroxyl groups participating in thermal curing, the cross - linked network was incomplete, resulting in poor water resistance, and the insufficient degree of chemical bonding also affected chemical resistance and adhesion; in Comparative Example 10, a single photo - initiator was used, causing insufficient or non - uniform UV curing, which affected the surface hardness, abrasion resistance and the fixation efficiency of the organic antibacterial agent, weakening the synergistic effect of the UV curing link in the dual curing; in Comparative Example 11, thermal curing was omitted, completely lacking the bulk polyurethane cross - linked network and the chemical anchoring of inorganic fillers, resulting in the complete loss of properties such as water and chemical resistance and adhesion that rely on the bulk structure; in Comparative Example 12, UV curing was omitted, so a rapidly cured hard surface layer could not be formed, with poor abrasion resistance, and the organic antibacterial agent was not covalently bonded, affecting its durability; in Comparative Example 13, one - time mixing was adopted, destroying the premise of fine - control of dispersion and reaction in the two - component system, resulting in uneven component dispersion, compatibility problems or incomplete reactions, forming a defective coating film, making it difficult for each performance index to reach the optimized level.

[0064] These comparative examples verified the mechanism of the improvement of the comprehensive performance of the present invention from the perspectives of system composition, curing process and operation process, etc.: Comparative Example 9 showed the importance of precise stoichiometric ratio for constructing a complete network; Comparative Example 10 emphasized the role of optimizing the photo - initiator system for UV curing efficiency; the results of Comparative Examples 11 and 12 fully proved that the dual mechanisms of UV curing and thermal curing are indispensable, and they act synergistically in terms of time and function, respectively contributing the key properties of the surface layer and the bulk phase, achieving performance complementarity; Comparative Example 13 illustrated that adopting a two - component system and the specified preparation and mixing process is a necessary process guarantee to ensure the effective synergy of each component, avoid adverse reactions and achieve the final high performance, reflecting the systematic advantages of the overall formulation and process design.

[0065] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing a UV resin coating, characterized in that: The preparation method of the UV resin coating, by weight parts, is as follows: premix the component A and the component B premix evenly; then add 16 - 20 parts of isocyanate curing agent; Continue to stir and mix to obtain the UV resin coating; The preparation of component A: Mix 100 parts of fluorinated waterborne polyurethane acrylate dispersion and 45 - 55 parts of waterborne hydroxyl polyurethane dispersion evenly, then successively add dipropylene glycol dimethyl ether and polyurethane dispersant, 2 - 3 parts of modified tea polyphenols, inhibitor, 4 parts of composite photoinitiator, and finally filter to obtain component A; The preparation of component B: Mix 7 parts of dipropylene glycol dimethyl ether and 13 parts of deionized water; add wetting agent; then slowly add 4 - 6 parts of functionalized nano - cerium dioxide and 2 - 3 parts of silver - loaded nano - silica, disperse at high speed for 20 min; then successively add leveling agent, defoaming agent and thickening agent; finally filter to obtain component B.

2. The preparation method of a UV resin coating according to claim 1, characterized in that: The composite photoinitiator is obtained by dissolving 1 - hydroxycyclohexyl phenyl ketone and bis(2,4,6 - trimethylbenzoyl) phenyl phosphine oxide in a weight - ratio of 1 - 2:1 in dipropylene glycol dimethyl ether.

3. The preparation method of a UV resin coating according to claim 1, characterized in that: The preparation method of the fluorinated waterborne polyurethane acrylate dispersion is as follows: dehydrate the mixture of 55 parts of polytetrahydrofuran glycol, 15 parts of polycarbonate glycol, 8 - 12 parts of perfluoropolyether glycol and 4.5 parts of dimethylolpropionic acid; then add 26 - 28 parts of isophorone diisocyanate, 30 parts of acetone, 0.08 part of dibutyltin dilaurate and react at 75 °C for 4 h to obtain a prepolymer; after the reaction is completed, lower the system temperature to 60 °C, add 9 parts of hydroxyethyl acrylate and react for 2 h; then add 3.4 parts of triethylamine and react for 30 min, disperse the obtained neutralized prepolymer solution in water under high - shear force; finally, carry out vacuum distillation at 50 °C to obtain the fluorinated waterborne polyurethane acrylate dispersion with a solid content of 35%.

4. The preparation method of a UV resin coating according to claim 1, characterized in that: The preparation method of the modified tea polyphenols is as follows: under nitrogen protection, dissolve 10 parts of tea polyphenols in 100 parts of anhydrous acetone, add 12 parts of triethylamine; add 16 - 20 parts of methacrylic anhydride at 5 °C; then react at 5 °C for 12 h and raise the temperature to 25 °C and continue to react for 6 h to complete esterification; after the reaction is completed, obtain the modified tea polyphenols through purification and drying.

5. The preparation method of a UV resin coating according to claim 1, characterized in that: The preparation method of the functionalized nano - cerium dioxide is as follows: first, perform plasma treatment on 10 parts of nano - cerium dioxide and disperse it in 100 parts of anhydrous ethanol, add 0.8 - 1.2 parts of (3 - aminopropyl)triethoxysilane; then heat to 78 °C and react for 8 h; the reaction product is centrifuged, washed and purified; finally, vacuum - dry at 60 °C for 12 h to obtain the functionalized nano - cerium dioxide.

6. The preparation method of a UV resin coating according to claim 5, characterized in that: The plasma treatment conditions are: use a mixed gas of oxygen and argon with a volume ratio of 4:1 for the nano - cerium dioxide powder, and perform plasma pretreatment at a power of 70 - 90 W and a pressure of 30 Pa for 4 - 6 min.

7. The preparation method of a UV resin coating according to claim 1, characterized in that: The preparation method of the silver-loaded nano-silica is as follows: Disperse 10 parts of nano-silica in ethanol, first add a solution prepared from 0.15 - 0.25 parts of silver nitrate and adsorb for 2 h, then add 0.1 part of sodium borohydride and react for 1 h; Disperse the washed and dried silver-loaded silica in 100 parts of anhydrous toluene, add 1 part of (3-aminopropyl)triethoxysilane, and reflux and react at 110 °C for 6 h; After the product is centrifuged, washed and purified, it is vacuum dried at 80 °C for 12 h to obtain the silver-loaded nano-silica.

8. Use of a UV resin coating as described in claim 1, characterized in that: After the UV resin coating is applied to the wooden board, it is pre-baked at 60 °C for 15 min, then UV cured, and finally the wooden board is post-baked at 70 - 80 °C for 60 - 90 min.

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