Environment-friendly water-based UV coating and preparation method thereof

Abstract

The present application relates to the field of paint, and particularly relates to an environment-friendly water-based UV paint and a preparation method thereof. The water-based UV paint comprises, in terms of weight fractions, 40-80 parts of polyurethane acrylate, 10-30 parts of acrylic monomer, 5-15 parts of diphenylmethane modified methacrylate, 1-5 parts of filler, 0.1-2 parts of photoinitiator, 0.5-1.5 parts of dispersant, 0.1-0.5 parts of defoaming agent, 0.1-1 parts of leveling agent and 30-60 parts of water. The water-based UV paint prepared by the present application uses water as the main solvent, significantly reduces VOC emission and meets the development trend of green paint. Through the synergistic effect of polyurethane acrylate and acrylic monomer, the use of active diluent in traditional UV paint is reduced, and the toxicity is further reduced. Meanwhile, the diphenylmethane modified methacrylate has good improvement on the wear resistance, corrosion resistance and adhesion of the paint.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of paint, in particular to an environment-friendly water-based UV paint and a preparation method thereof. BACKGROUND

[0002] The water-based UV paint gradually replaces the traditional paint with its superfast curing speed and excellent physical and chemical properties, and the water-based UV paint eliminates the toxicity and irritation of the traditional paint, and is rapidly applied to the fields of bamboo wood floor, furniture, glass, plastic, metal and the like, and becomes a new type of environment-friendly material.

[0003] The water-based UV curing system has the advantages of non-toxicity, non-pollution, non-irritation, fast curing speed, excellent coating film performance, energy saving, production safety and the like, but the water-based UV paint in the prior art mainly has the following shortcomings: firstly, since the water-based paint forms a relatively thin paint film on the surface of the base material, the hardness and toughness of the paint film are not enough when rubbing, and the paint film is easily abraded, so that the wear resistance of the paint film needs to be improved; secondly, the water-based UV paint is mainly applied to the fields of wood floor and furniture, and is rarely applied to the outer wall prefabricated board, mainly because the outer wall prefabricated board is usually used outdoors, and the corrosion resistance, adhesion and the like of the paint are required to be higher outdoors. Therefore, it is necessary to provide an environment-friendly water-based UV paint to overcome the above-mentioned defects, so as to expand the application field. SUMMARY

[0004] In view of the problems in the prior art, the purpose of the present application is to provide an environment-friendly water-based UV paint and a preparation method thereof.

[0005] The purpose of the present application is realized by adopting the following technical solutions:

[0006] In the first aspect, the present application provides an environment-friendly water-based UV paint, which comprises, in terms of weight fraction:

[0007] 40-80 parts of polyurethane acrylate, 10-30 parts of acrylic monomer, 5-15 parts of diphenylmethane modified methacrylate, 1-5 parts of filler, 0.1-2 parts of photoinitiator, 0.5-1.5 parts of dispersing agent, 0.1-0.5 parts of defoaming agent, 0.1-1 parts of leveling agent, and 30-60 parts of water.

[0008] Preferably, the polyurethane acrylate is a hexafunctional polyurethane acrylate with a trade name of Changxing Etercure 6145-100 or Desman AgiSyn 230A2.

[0009] Preferably, the acrylic monomer is one or a mixture of more than one of acrylic acid (AA), methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), hydroxyethyl acrylate (HEA), methyl methacrylate (MMA), hydroxyethyl methacrylate (HEMA), hydroxypropyl methacrylate (HPMA).

[0010] Preferably, the acrylic monomer is a mixture of methyl acrylate (MA), butyl acrylate (BA), methyl methacrylate (MMA), and hydroxyethyl methacrylate (HEMA) in a mass ratio of 1-2:0.6-1.2:2-4:1.5-2.5.

[0011] Preferably, the filler is silane-activated nanometer diatomite, and the preparation method comprises:

[0012] Mixing the nanometer diatomite and the aqueous solution of ethanol and ultrasonic dispersion, drop the silane coupling agent, reflux stirring for 2-4 hours, centrifugation, water washing and drying to obtain silane-activated nanometer diatomite.

[0013] More preferably, the particle size of the nanometer diatomite is 100±10 nm, and the mass fraction of the aqueous solution of ethanol is 40%-60%.

[0014] More preferably, the silane coupling agent is one or a mixture of more than one of KH-550, KH-560, and KH-571.

[0015] More preferably, the mass-volume ratio of the nanometer diatomite, the silane coupling agent, and the aqueous solution of ethanol is 1 g:(0.1-0.3) g:(10-20) mL.

[0016] Preferably, the photoinitiator is 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide (TPO) or hydroxycyclohexane phenyl ketone (photoinitiator 184).

[0017] Preferably, the dispersant is one or a mixture of more than one of BYK-2013, BYK-190, BYK-192, and BYK-110. More preferably, it is BYK-2013.

[0018] Preferably, the defoaming agent is one or a mixture of more than one of Dow Corning DC-57, Dow Corning DC-51, and Degussa TEGO-825. More preferably, it is Dow Corning DC-57.

[0019] Preferably, the leveling agent is one or a mixture of more than one of TEGO-410, TEGO-440, and TEGO-432. More preferably, it is TEGO-410.

[0020] Preferably, the preparation method of the diphenylmethane-modified methacrylate comprises:

[0021] The 2,3-epoxypropyl methacrylate (GMA) and 4,4'-diamino diphenyl methane (MDA) are weighed and added into the organic solvent, the catalyst is added dropwise, the reaction is treated by stirring and heating, after the reaction is completed, the solvent is removed, and after purification and drying, the diphenyl methane modified methacrylate is obtained.

[0022] Preferably, the mass-volume ratio of the 2,3-epoxypropyl methacrylate (GMA), 4,4'-diamino diphenyl methane (MDA) and the organic solvent is (1.08-1.19) g:0.75 g:(10-20) mL.

[0023] Preferably, the organic solvent is one of acetone, tetrahydrofuran and N,N-dimethylformamide.

[0024] Preferably, the catalyst is triethylamine, and the addition amount is 1%-3% of the mass of 4,4'-diamino diphenyl methane.

[0025] Preferably, the reaction heating process includes: first stirring at 30-40 DEG C for 1 h, and then heating to 50-60 DEG C and continuing to stir for 2-5 h.

[0026] Preferably, the stirring speed of the reaction is 200-500 r / min.

[0027] Preferably, the purification is a purification treatment for 24-48 h in pure water using a dialysis bag with a molecular weight cut-off of 5000-8000 Da.

[0028] In a second aspect, the present application provides a preparation method of an environmentally friendly water-based UV paint, comprising the following steps:

[0029] In step 1, the polyurethane acrylate, acrylic monomer, diphenyl methane modified methacrylate, filler and dispersant are weighed and added into deionized water, and dispersed at a speed of 300-500 r / min for 20-30 min.

[0030] In step 2, the photoinitiator, defoaming agent and leveling agent are weighed and added into the mixture in step 1, and dispersed at a speed of 200-400 r / min for 5-15 min, to obtain the environmentally friendly water-based UV paint.

[0031] The present application has the following beneficial effects:

[0032] 1. The water-based UV coating prepared by this invention uses water as the main solvent, significantly reducing VOC emissions and aligning with the trend of green coating development. Through the synergistic effect of polyurethane acrylate and acrylic monomers, the use of reactive diluents in traditional UV coatings is reduced, further lowering toxicity. Simultaneously, diphenylmethane-modified methacrylate significantly improves the coating's abrasion resistance, corrosion resistance, and adhesion.

[0033] 2. Diphenylmethane-modified methacrylate is prepared from 2,3-glycidyl methacrylate (GMA) and 4,4'-diaminodiphenylmethane (MDA) as raw materials through an epoxy-amino bonding reaction. Compared to directly adding GMA and MDA, this invention first performs a bonding reaction between GMA and MDA. The epoxy groups of GMA and the amino groups of MDA react to form a multi-linked network, which has better high adhesion and curability, thereby further improving the wear resistance and adhesion of the material.

[0034] 3. The diphenylmethane structure introduced into diphenylmethane-modified methacrylate has good chemical stability and enhanced resistance to chemical erosion, thus also enhancing the corrosion resistance of the coating. Detailed Implementation

[0035] The technical solution of the present invention is illustrated below through specific examples. It should be understood that the one or more method steps mentioned in the present invention do not preclude the existence of other method steps before or after the combined steps, or the insertion of other method steps between these explicitly mentioned steps; it should also be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, unless otherwise stated, the numbering of each method step is merely a convenient tool for identifying each method step, and not for limiting the order of the method steps or defining the scope of the present invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the present invention.

[0036] To better understand the above technical solutions, exemplary embodiments of the present invention are described in more detail below. While exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present invention and to fully convey the scope of the invention to those skilled in the art.

[0037] The present invention will be further described below with reference to the following embodiments.

[0038] Example 1

[0039] An environmentally friendly water-based UV coating, comprising, by weight:

[0040] Polyurethane acrylate 60 parts, acrylic monomer 20 parts, diphenylmethane modified methacrylate 10 parts, filler 3 parts, photoinitiator 0.7 parts, dispersant 1 part, defoamer 0.3 parts, leveling agent 0.4 parts, water 45 parts.

[0041] Among them, the polyurethane acrylate is a hexafunctional polyurethane acrylate, and the brand is Changxing Etercure 6145-100;

[0042] Among them, the acrylic monomer is a mixture of methyl acrylate (MA), butyl acrylate (BA), methyl methacrylate (MMA), and hydroxyethyl methacrylate (HEMA) in a mass ratio of 1.5:0.9:3:2.

[0043] Among them, the filler is silane-activated nanometer diatomite, and the preparation method comprises:

[0044] 1g of nanometer diatomite with a particle size of 100±10nm and 15mL of an aqueous solution of 50% ethanol were mixed and uniformly ultrasonically dispersed, 0.2g of silane coupling agent KH-550 was added dropwise, refluxed and stirred for 3h, then centrifuged, washed with water and dried to obtain silane-activated silicon dioxide.

[0045] Among them, the photoinitiator is 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide (TPO); the dispersant is BYK-2013; the defoamer is Dow Corning DC-57; and the leveling agent is TEGO-410.

[0046] Among them, the preparation method of the diphenylmethane modified methacrylate comprises:

[0047] 1.14g of 2,3-epoxypropyl methacrylate (GMA) and 0.75g of 4,4'-diaminodiphenyl methane (MDA) were weighed into 15mL of acetone, triethylamine was added as a catalyst, the amount of triethylamine was 2% of the mass of 4,4'-diaminodiphenyl methane, first stirred at 35℃ for 1h, then heated to 55℃, and continued to stir for 3h at a stirring speed of 300r / min, after the reaction was completed, the solvent was removed by rotary evaporation, and the dialysis bag with a molecular weight cut-off of 7000Da was used for purification treatment for 24h, and then vacuum dried to obtain the diphenylmethane modified methacrylate.

[0048] The preparation method of the above-mentioned environmentally friendly water-based UV coating comprises the following steps:

[0049] Step 1: Weigh the polyurethane acrylate, acrylic monomer, diphenylmethane modified methacrylate, filler and dispersant into deionized water, and disperse at a speed of 400r / min for 25min;

[0050] Step 2, add the photoinitiator, defoaming agent and leveling agent into the mixture in step 1, and disperse at a speed of 300 r / min for 10 min, to obtain the environmentally friendly water-based UV coating.

[0051] Example 2

[0052] An environmentally friendly water-based UV coating, comprising, in terms of weight fractions:

[0053] 40 parts of polyurethane acrylate, 10 parts of acrylic monomer, 5 parts of diphenylmethane modified methacrylate, 1 part of filler, 0.5 part of photoinitiator, 0.5 part of dispersant, 0.1 part of defoaming agent, 0.1 part of leveling agent, and 30 parts of water.

[0054] The polyurethane acrylate is a hexafunctional polyurethane acrylate, and the brand is AgiSyn 230A2 of Desma.

[0055] The acrylic monomer is a mixture of methyl acrylate (MA), butyl acrylate (BA), methyl methacrylate (MMA) and hydroxyethyl methacrylate (HEMA) in a mass ratio of 1:0.6:2:1.5.

[0056] The filler is silane-activated nanometer diatomite, and the preparation method comprises:

[0057] 1g of nanometer diatomite with a particle size of 100±10nm and 10mL of an aqueous solution of ethanol with a mass fraction of 40% are mixed and ultrasonically dispersed uniformly, 0.1g of silane coupling agent KH-560 is added dropwise, reflux stirring is performed for 2h, centrifugation, water washing and drying are performed, and silane-activated silicon dioxide is obtained.

[0058] The photoinitiator is hydroxycyclohexane phenone (photoinitiator 184); the dispersant is BYK-190; the defoaming agent is Dow Corning DC-51; and the leveling agent is TEGO-440.

[0059] The preparation method of the diphenylmethane modified methacrylate comprises:

[0060] 1.08g of methyl methacrylate-2,3-epoxypropyl (GMA) and 0.75g of 4,4'-diamino diphenyl methane (MDA) are weighed into 10mL of tetrahydrofuran, a small amount of triethylamine is added as a catalyst, the amount of triethylamine is 1% of the mass of 4,4'-diamino diphenyl methane, stirring is performed at a temperature of 30℃ for 1h, then the temperature is raised to 50℃, and stirring is continued for 2h at a stirring speed of 200r / min, after the reaction is completed, the solvent is removed by rotary evaporation, dialysis bags with a molecular weight cut-off of 7000Da are used for purification treatment for 24h, and vacuum drying is performed, to obtain the diphenylmethane modified methacrylate.

[0061] The preparation method of the environmentally-friendly water-based UV coating comprises the following steps:

[0062] In step 1, polyurethane acrylate, acrylic monomer, diphenylmethane modified methacrylate, filler and dispersant are weighed and added to deionized water, and dispersed at a speed of 300 r / min for 30 min.

[0063] In step 2, photoinitiator, defoaming agent and leveling agent are weighed and added to the mixture in step 1, and dispersed at a speed of 200 r / min for 15 min, to obtain the environmentally-friendly water-based UV coating.

[0064] Example 3

[0065] An environmentally-friendly water-based UV coating comprises, by weight fraction:

[0066] Polyurethane acrylate 50 parts, acrylic monomer 15 parts, diphenylmethane modified methacrylate 10 parts, filler 2 parts, photoinitiator 1 part, dispersant 1.2 parts, defoaming agent 0.2 parts, leveling agent 0.6 parts, and water 50 parts.

[0067] The polyurethane acrylate is a six-functional polyurethane acrylate with a brand of Changxing Etercure 6145-100.

[0068] The acrylic monomer is a mixture of methyl acrylate (MA), butyl acrylate (BA), methyl methacrylate (MMA) and hydroxyethyl methacrylate (HEMA) in a mass ratio of 1.2:0.7:2.5:2.

[0069] The filler is silane-activated nanometer diatomite, and the preparation method comprises:

[0070] 1g of nanometer diatomite with a particle size of 100±10nm and 15mL of an aqueous solution of ethanol with a mass fraction of 50% are mixed and ultrasonically dispersed uniformly, 0.2g of silane coupling agent KH-560 is added dropwise, reflux stirring is performed for 3h, centrifugation, water washing and drying are performed, and silane-activated silicon dioxide is obtained.

[0071] The photoinitiator is hydroxycyclohexane phenyl ketone (photoinitiator 184); the dispersant is BYK-192; the defoaming agent is Dow Corning DC-51; and the leveling agent is TEGO-410.

[0072] The preparation method of the diphenylmethane modified methacrylate comprises:

[0073] 1.16 g of 2,3-epoxypropyl methacrylate (GMA) and 0.75 g of 4,4'-diaminodiphenyl methane (MDA) were weighed into 16 mL of acetone, and triethylamine was added as a catalyst at a dosage of 1.5% of the mass of 4,4'-diaminodiphenyl methane, and stirred at 40°C for 1 h, then heated to 55°C, and stirred at 200 r / min for 4 h. After the reaction was completed, the solvent was removed by rotary evaporation, and the product was purified by dialysis for 24 h using a dialysis bag with a molecular weight cut-off of 7000 Da, and then vacuum dried to obtain the diphenyl methane modified methacrylate.

[0074] The preparation method of the environmentally friendly water-based UV coating comprises the following steps:

[0075] In step 1, polyurethane acrylate, acrylic monomer, diphenyl methane modified methacrylate, filler and dispersant were weighed into deionized water, and dispersed at a speed of 400 r / min for 20 min;

[0076] In step 2, photoinitiator, defoaming agent and leveling agent were weighed into the mixture of step 1, and dispersed at a speed of 300 r / min for 15 min to obtain the environmentally friendly water-based UV coating.

[0077] Example 4

[0078] An environmentally friendly water-based UV coating, according to the weight fraction, comprises:

[0079] Polyurethane acrylate 80 parts, acrylic monomer 30 parts, diphenyl methane modified methacrylate 15 parts, filler 5 parts, photoinitiator 1.2 parts, dispersant 1.5 parts, defoaming agent 0.5 parts, leveling agent 1 part, and water 60 parts.

[0080] The polyurethane acrylate is a hexafunctional polyurethane acrylate, and the brand is AgiSyn 230A2 of Deshman.

[0081] The acrylic monomer is a mixture of methyl acrylate (MA), butyl acrylate (BA), methyl methacrylate (MMA) and hydroxyethyl methacrylate (HEMA) in a mass ratio of 2:1.2:4:2.5.

[0082] The filler is silane-activated nanometer diatomite, and the preparation method comprises:

[0083] 1 g of nanometer diatomite with a particle size of 100±10 nm and 20 mL of an aqueous solution of 60% ethanol were mixed and ultrasonically dispersed uniformly, and 0.3 g of silane coupling agent KH-571 was added dropwise. After reflux stirring for 4 h, centrifugation, water washing and drying, silane-activated silicon dioxide was obtained.

[0084] The photoinitiator is hydroxyl cyclohexane phenone (photoinitiator 184), the dispersant is BYK-110, the defoaming agent is DEGOL TEGO-825, and the leveling agent is TEGO-432.

[0085] The preparation method of the diphenylmethane modified methacrylate comprises the following steps:

[0086] The diphenylmethane modified methacrylate is prepared by the following steps: 1.08-1.19 g of 2,3-epoxypropyl methacrylate (GMA) and 0.75 g of 4,4'-diamino diphenyl methane (MDA) are weighed and added into (10-20) mL of N,N-dimethylformamide, a small amount of triethylamine is added as a catalyst, the amount of the catalyst is 1-3% of the mass of the 4,4'-diamino diphenyl methane, stirring is performed at a temperature of 30-40 DEG C for 1 h, then the temperature is increased to 50-60 DEG C, and stirring is continuously performed at a speed of 200-500 r / min for 2-5 h, after the reaction is completed, the solvent is removed by rotary evaporation, dialysis bags with a molecular weight cut-off of 7000 Da are used for purification treatment for 24-48 h, and vacuum drying is performed, so as to obtain the diphenylmethane modified methacrylate.

[0087] The preparation method of the environment-friendly water-based UV paint comprises the following steps:

[0088] In step 1, polyurethane acrylate, acrylic monomer, diphenylmethane modified methacrylate, filler and dispersant are weighed and added into deionized water, and are dispersed at a speed of 500 r / min for 20 min.

[0089] In step 2, photoinitiator, defoaming agent and leveling agent are weighed and added into the mixture in step 1, and are dispersed at a speed of 400 r / min for 5 min, so as to obtain the environment-friendly water-based UV paint.

[0090] Comparative Example 1

[0091] The environment-friendly water-based UV paint comprises the following components in parts by weight:

[0092] The environment-friendly water-based UV paint comprises the following components in parts by weight: polyurethane acrylate 70 parts, acrylic monomer 20 parts, filler 3 parts, photoinitiator 0.7 part, dispersant 1 part, defoaming agent 0.3 part, leveling agent 0.4 part and water 45 parts.

[0093] The difference between the environment-friendly water-based UV paint and the environment-friendly water-based UV paint in Example 1 is that the diphenylmethane modified methacrylate is replaced by an equal amount of polyurethane acrylate, and the other components and the preparation process are the same as those in Example 1.

[0094] Comparative Example 2

[0095] The environment-friendly water-based UV paint comprises the following components in parts by weight:

[0096] Polyurethane acrylate 60 parts, acrylic monomer 20 parts, 2,3-epoxypropyl methacrylate 10 parts, filler 3 parts, photoinitiator 0.7 parts, dispersant 1 part, defoamer 0.3 parts, leveling agent 0.4 parts, water 45 parts.

[0097] The difference from Example 1 is that the diphenylmethane modified methacrylate is replaced with an equal amount of 2,3-epoxypropyl methacrylate (GMA), and the other ingredients and preparation process are the same as Example 1.

[0098] Comparative Example 3

[0099] An environmentally friendly water-based UV coating, according to parts by weight, includes:

[0100] Polyurethane acrylate 60 parts, acrylic monomer 20 parts, 2,3-epoxypropyl methacrylate 6 parts, 4,4'-diamino diphenyl methane 4 parts, filler 3 parts, photoinitiator 0.7 parts, dispersant 1 part, defoamer 0.3 parts, leveling agent 0.4 parts, water 45 parts.

[0101] The difference from Example 1 is that the diphenylmethane modified methacrylate is replaced with separate addition of 2,3-epoxypropyl methacrylate (GMA) and 4,4'-diamino diphenyl methane (MDA), and the other ingredients and preparation process are the same as Example 1.

[0102] Experimental Example

[0103] In order to more clearly illustrate the content of the present application, the performance of the water-based UV coating prepared by Example 1 and Comparative Examples 1-3 is experimentally detected, as follows:

[0104] Take 4 pieces of SPCC cold-rolled sheet of the same size, and mark the numbers, respectively. The water-based UV coating prepared by Example 1 and Comparative Examples 1-3 is coated on the cold-rolled sheet marked with the number by vacuum spraying, the spraying thickness is 75μm, and after spraying, it is cured under the irradiation of UV light with a radiation energy of 1000mJ / cm 2 for 30s, and the performance is detected after curing.

[0105] The detection items include:

[0106] The pencil hardness detection refers to GB / T 6739-2022, and the scratch resistance of the coating is tested.

[0107] The adhesion detection refers to GB / T 9286-2021, and the adhesive tape is peeled off after gridding with a 1mm spacing, and the falling area is evaluated (0-5 levels, 0 level is the best).

[0108] The abrasion resistance was detected according to ASTM D4060-19, using CS-10 abrasive wheel, load 500g, mass loss was measured after 1000 rotations.

[0109] The alkali resistance and acid resistance were detected according to GB / T 9274-1988, the alkali resistance detection was immersed in 0.1 mol / L NaOH solution for 72h, the acid resistance detection was immersed in 0.05 mol / L H2SO4 solution for 72h, after drying, whether there were phenomena such as blistering, peeling and the like was observed.

[0110] The detection results were as follows:

[0111] Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Hardness (pencil) 3H 2H 2H 3H Adhesion (grade) 0 1 1 1 Wear mass loss (mg) 17 42 33 25 Resistance to alkali Essentially intact Partially blistered Partially blistered Essentially intact Resistance to acid Essentially intact Essentially intact Essentially intact Essentially intact

[0112] From the above detection, it can be seen that, compared with the comparative example, the water-based UV coating prepared in the example 1 of the present application not only has excellent performance in hardness and acid and alkali resistance, but also has better performance in adhesion and abrasion resistance.

[0113] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present application.

Claims

1. An environmentally friendly water-based UV coating, characterized in that, By weight, it includes: 40-80 parts polyurethane acrylate, 10-30 parts acrylic monomer, 5-15 parts diphenylmethane modified methacrylate, 1-5 parts filler, 0.1-2 parts photoinitiator, 0.5-1.5 parts dispersant, 0.1-0.5 parts defoamer, 0.1-1 parts leveling agent, and 30-60 parts water; The polyurethane acrylate is a hexafunctional polyurethane acrylate, with the brand name Changxing Etercure 6145-100 or DSM AgiSyn 230A2. The acrylic monomers are one or a mixture of multiple selected from acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, hydroxyethyl acrylate, methyl methacrylate, hydroxyethyl methacrylate, and hydroxypropyl methacrylate. The preparation method of the diphenylmethane-modified methacrylate includes: Weigh 2,3-epoxypropyl methacrylate and 4,4'-diaminodiphenylmethane and add them to an organic solvent. Add a catalyst dropwise, heat and stir to react. After the reaction is complete, remove the solvent, purify and dry to obtain diphenylmethane-modified methacrylate.

2. The environmentally friendly water-based UV coating according to claim 1, characterized in that, The acrylic monomers are obtained by mixing methyl acrylate, butyl acrylate, methyl methacrylate, and hydroxyethyl methacrylate in a mass ratio of 1-2:0.6-1.2:2-4:1.5-2.

5.

3. The environmentally friendly water-based UV coating according to claim 1, characterized in that, The filler is silane-activated nano-diatomite, and the preparation method includes: Aqueous solutions of nano-diatomaceous earth and ethanol are mixed and ultrasonically dispersed. A silane coupling agent is added dropwise, and the mixture is refluxed and stirred for 2-4 hours. After centrifugation, washing with water, and drying, silane-activated silica is obtained. The silane coupling agent is one or a mixture of KH-550, KH-560, and KH-571. The mass-volume ratio of the aqueous solution of nano-diatomaceous earth, silane coupling agent, and ethanol is 1 g:(0.1-0.3) g:(10-20) mL.

4. The environmentally friendly water-based UV coating according to claim 1, characterized in that, The photoinitiator is 2,4,6-trimethylbenzoyl-diphenylphosphine oxide or photoinitiator 184; the dispersant is one or a mixture of BYK-2013, BYK-190, BYK-192, and BYK-110; the defoamer is one or a mixture of Dow Corning DC-57, Dow Corning DC-51, and TEGO-825; and the leveling agent is one or a mixture of TEGO-410, TEGO-440, and TEGO-432.

5. The environmentally friendly water-based UV coating according to claim 1, characterized in that, The mass-volume ratio of 2,3-epoxypropyl methacrylate, 4,4'-diaminodiphenylmethane, and organic solvent is (1.08-1.19) g: 0.75 g: (10-20) mL; the catalyst is triethylamine, and the amount added is 1%-3% of the mass of 4,4'-diaminodiphenylmethane.

6. The environmentally friendly water-based UV coating according to claim 1, characterized in that, The reaction heating process includes: first stirring at 30-40℃ for 1 hour, then heating to 50-60℃ and continuing stirring for 2-5 hours.

7. A method for preparing the environmentally friendly water-based UV coating according to claim 1, characterized in that, Includes the following steps: Step 1: Weigh polyurethane acrylate, acrylic monomers, diphenylmethane modified methacrylate, filler and dispersant and add them to deionized water, and disperse at a speed of 300-500 r / min for 20-30 min. Step 2: Weigh out the photoinitiator, defoamer, and leveling agent and add them to the mixture from step 1. Disperse the mixture at a speed of 200-400 r / min for 5-15 min to obtain an environmentally friendly water-based UV coating.