A high-performance polyurethane paint and its preparation method

Abstract

The present invention discloses a high-performance polyurethane paint and a preparation method thereof, in particular relating to the technical field of coatings. The high-performance polyurethane paint comprises, by weight parts: 45-60 parts of a functional polyurethane prepolymer, 4-7 parts of modified kaolin, 1-3 parts of propylene glycol methyl ether acetate, 0.1-0.5 part of an antifoaming agent, 0.2-0.6 part of a leveling agent, 10-15 parts of titanium dioxide, and 0.5-1 part of a dispersant; the preparation steps of the functional polyurethane prepolymer are as follows: poly(tetramethylene ether) glycol, a diisocyanate and dibutyltin dilaurate are mixed for a first reaction, and then a functionalized diol monomer is added for a second reaction to obtain the product. The coating can prevent mildew and antibacterial, and has good waterproof self-cleaning performance, mechanical properties and storage stability.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, and in particular to a high-performance polyurethane paint and a preparation method thereof. Background Art

[0002] Paint is a chemical mixture coating that can be firmly covered on the surface of an object for protection, decoration, marking and other special purposes. Traditional oil-based paint, with drying oil as the main film-forming substance, can provide certain decoration and protection, but it will release a large amount of formaldehyde and other volatile organic compounds (VOC) during its manufacturing, construction and curing. With the enhancement of health awareness and environmental protection concepts, people's requirements for the performance of paint are increasing. Polyurethane paint does not contain benzene organic solvents, is green and environmentally friendly, and can be applied by spraying, brushing, dipping and other construction methods, which is easy to realize automatic coating. The paint has good film formation, high gloss, low VOC content and low odor, and is increasingly recognized by consumers.

[0003] At present, the research on polyurethane paints is mainly focused on improving the flame retardancy, wear resistance and corrosion resistance of paints, but key functions such as waterproofing, self-cleaning and antibacterial and mildew resistance are often overlooked.

[0004] Based on this, it is necessary to improve the formula of polyurethane paint and develop coatings that can effectively inhibit mold growth and are waterproof and self-cleaning to meet the market's urgent demand for such high-performance products. Summary of the invention

[0005] In order to overcome the deficiencies of the prior art, one of the purposes of the present invention is to provide a high-performance polyurethane paint. The paint coating can effectively inhibit the growth of bacteria and molds, and has good waterproof and self-cleaning properties, which can fully meet market demand.

[0006] The second purpose of the present invention is to provide a method for preparing high-performance polyurethane paint, which has a simple and feasible process and provides new technical support for the preparation of high-performance polyurethane paint.

[0007] One of the purposes of the present invention is achieved by the following technical solution:

[0008] A high-performance polyurethane paint, comprising the following raw materials by weight: 45-60 parts of functional polyurethane prepolymer, 4-7 parts of modified kaolin, 1-3 parts of propylene glycol methyl ether acetate, 0.1-0.5 parts of defoaming agent, 0.2-0.6 parts of leveling agent, 10-15 parts of titanium dioxide, and 0.5-1 parts of dispersant;

[0009] The preparation steps of the functional polyurethane prepolymer are as follows:

[0010] (1) Preparation of functionalized diol monomers;

[0011] (2) Mix polytetrahydrofuran diol, diisocyanate and dibutyltin dilaurate for the first reaction, and then add the functionalized diol monomer for the second reaction to obtain a functional polyurethane prepolymer.

[0012] Further, in step (2), the molar ratio of the polytetrahydrofuran diol, diisocyanate and functionalized diol monomer is 1:(2.5 - 4):(0.3 - 0.8); the dosage of the dibutyltin dilaurate is 0.05 - 0.2% of the total weight of the polytetrahydrofuran diol and diisocyanate.

[0013] Still further, the diisocyanate is one of isophorone diisocyanate, toluene diisocyanate, and hexamethylene diisocyanate.

[0014] Further, in step (2), the temperature of the first reaction is 75 - 85°C and the time is 1 - 3 h; the temperature of the second reaction is 75 - 85°C and the time is 2 - 4 h.

[0015] Further, the preparation steps of the functionalized diol monomer in step (1) are as follows:

[0016]

[0017] a. Under an inert gas atmosphere, introduce CO2 into the mixed solution of ethylene glycol diglycidyl ether and tetraethylammonium bromide to a certain pressure, and heat for reaction. After the reaction is completed, collect the crude product and wash and dry it to obtain an intermediate product;

[0018] b. Add the intermediate product and 7 - amino[1,2,4]triazolo[1,5 - a]pyrimidine - 6 - carboxylic acid to a solvent for heating reaction, precipitate and wash the reactant with ice ether, and then dry to obtain the functionalized diol monomer.

[0019] Further, in step a, the mass ratio of the ethylene glycol diglycidyl ether to the tetraethylammonium bromide is 1:0.01 - 0.015; the pressure is 4 - 5 MPa; the temperature of the heating reaction is 110 - 130°C and the time is 22 - 26 h.

[0020] Further, in step b, the mass ratio of the intermediate product to the 7 - amino[1,2,4]triazolo[1,5 - a]pyrimidine - 6 - carboxylic acid is 1:0.6 - 1.5, the temperature of the heating reaction is 60 - 80°C and the time is 18 - 24 h.

[0021] Further, the preparation steps of the modified kaolin are as follows:

[0022] Add vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate and an emulsifier to the dopamine hydrochloride solution for emulsification, and then add CuSO4 . 5H2O, H2O2 and kaolin for soaking treatment. Collect the product, wash and dry it to obtain the product.

[0023] The principle of preparing the modified kaolin in the present invention is as follows: CuSO4 / H2O2 is used as an initiator to first initiate the copolymerization of dopamine to form polydopamine; polydopamine can also be used as an initiator to induce the polymerization of vinyl(trifluoromethyl)dimethylsilane and deposit it on kaolin.

[0024] Furthermore, the mass ratio of dopamine hydrochloride, vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate, emulsifier, CuSO4 . 5H2O, H2O2 and kaolin is 1:(8.3 - 8.5):(3.25 - 3.4):(6.5 - 7.5):(0.4 - 0.45):(1.1 - 1.46):(1.5 - 2.5).

[0025] Furthermore, the temperature of the soaking treatment is 70 - 80°C and the time is 2 - 3 h.

[0026] Furthermore, the defoamer is one of BYK-066N, BYK-055, BYK-057; the leveling agent is BYK-300; the dispersant is BYK-110 or BYK-103; the titanium dioxide is titanium dioxide 577.

[0027] The second object of the present invention is achieved by the following technical solution:

[0028] The preparation method of the above high-performance polyurethane paint includes the following steps: according to the weight ratio, mix the functional polyurethane prepolymer, modified kaolin, defoamer, propylene glycol methyl ether acetate, dispersant, titanium dioxide and leveling agent and stir evenly to obtain the high-performance polyurethane paint.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] 1. The present invention provides a high-performance polyurethane paint, which not only has excellent antibacterial and mildew-proof properties, but also has excellent waterproof and self-cleaning properties.

[0031] 2. The raw materials of the high-performance polyurethane paint of the present invention include a functional polyurethane prepolymer. When preparing the functional polyurethane prepolymer, a functionalized diol monomer is introduced, endowing the coating with antibacterial and mildew-proof properties and stability. Specifically, the functionalized diol monomer is prepared by using 7-amino[1,2,4]triazolo[1,5-A]pyrimidine-6-carboxylic acid and ethylene glycol diglycidyl ether. It cleverly combines the antibacterial active triazolopyrimidine structure and carboxylic acid group. After being introduced into the polyurethane segment through copolymerization reaction, it can significantly improve the antibacterial and mildew-proof performance of the coating. At the same time, the introduction of the carboxylic acid group also significantly improves the storage stability of the polyurethane paint.

[0032] 3. The raw materials of the high-performance polyurethane paint of the present invention also add modified kaolin. The introduction of modified kaolin not only enhances the waterproof and self-cleaning performance of the coating, but also enhances the stability and antibacterial property of the coating. Specifically, in the present invention, CuSO4 / H2O2 is used to initiate the co-deposition of polydopamine / polyvinyl(trifluoromethyl)dimethylsilane on the surface of kaolin for modification. On the one hand, the surface energy extremely low trifluoromethyl (-CF3) is introduced through polyvinyl(trifluoromethyl)dimethylsilane, thereby enhancing the waterproof and self-cleaning performance of the coating; on the other hand, the formed polydopamine contains copper ions and catechol groups, forming a metal-phenol network, which not only improves the dispersibility of kaolin, but also further enhances the stability and antibacterial property of the coating.

[0033] 4. The present invention also provides a preparation method of the above high-performance polyurethane paint, which is simple and feasible, providing new technical support for the preparation of high-performance polyurethane paint. Specific Embodiments

[0034] Next, specific embodiments of the present invention will be combined to clearly and completely describe the technical solutions 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 in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present invention.

[0035] The defoamer, leveling agent, dispersant, and titanium dioxide of the present invention are obtained through conventional commercial channels. Among them, the defoamer involved in the present invention is one of BYK-066N, BYK-055, and BYK-057; the leveling agent is BYK-300; the dispersant is BYK-110 or BYK-103; the titanium dioxide is titanium dioxide 577.

[0036] Example 1

[0037] A high-performance polyurethane paint is composed of the following components by weight: 55 parts of a functional polyurethane prepolymer, 5 parts of modified kaolin, 2 parts of propylene glycol methyl ether acetate, 0.3 part of BYK-066N, 0.4 part of BYK-300, 0.75 part of BYK-110, and 12 parts of titanium dioxide 577;

[0038] The preparation steps of the functional polyurethane prepolymer are as follows:

[0039] (1) Preparation of a functionalized diol monomer:

[0040]

[0041] a. Weigh ethylene glycol diglycidyl ether and tetraethylammonium bromide according to a mass ratio of 1:0.012 respectively, then dissolve ethylene glycol diglycidyl ether and tetraethylammonium bromide in dichloromethane, and add them to a high-pressure reactor, where the concentration of ethylene glycol diglycidyl ether in dichloromethane is controlled to be 0.25 mg / mL; then, under nitrogen protection, CO2 is introduced into the reactor until the pressure in the reactor reaches 4.0 MPa, and the reactants are stirred at 120 °C for 24 h. Then, the reactor is cooled to room temperature, and the remaining CO2 is released and the pressure is reduced to atmospheric pressure. The obtained crude product is washed with dichloromethane and dried in a vacuum oven at 30 °C for 24 h to obtain an intermediate product;

[0042] b. Weigh the intermediate product and 7-amino[1,2,4]triazolo[1,5-A]pyrimidine-6-carboxylic acid according to a mass ratio of 1:1.1 respectively, add the intermediate product and 7-amino[1,2,4]triazolo[1,5-A]pyrimidine-6-carboxylic acid to dimethyl sulfoxide, where the concentration of the intermediate product in dimethyl sulfoxide is 0.05 g / mL; under a nitrogen atmosphere, after reacting at 70 °C for 20 h, the reactants are precipitated with ice ether and washed 3 times, and then dried in a vacuum oven at 40 °C for 48 h to obtain the functionalized diol monomer. 1 H NMR(C 22 H 24 N 10 O 12 , 400 MHz, d6-DMSO) δ 3.44 - 3.48 (m, 2H), 3.54 (s, 4H), 3.60 - 3.73 (m,6H), 3.94 (s, 2H), 4.85 - 4.89 (m, 2H), 7.80 (s, 2H), 8.62 (s, 2H), 10.47 (s,2H), 11.95 (s, 2H);MS (ESI) m / z = 620.16 [M], found 620.15.

[0043] (2) Weigh polytetrahydrofuran diol, isophorone diisocyanate and functionalized diol monomer according to the molar ratio of 1:3:0.5 respectively; then mix polytetrahydrofuran diol, isophorone diisocyanate and dibutyltin dilaurate, where the dosage of dibutyltin dilaurate is 0.1% of the total weight of polytetrahydrofuran diol and isophorone diisocyanate. React at 80 °C for 2 h under N2 atmosphere, then add the functionalized diol monomer and react for 3 h to obtain a functional polyurethane prepolymer.

[0044] The preparation method of the modified kaolin is as follows:

[0045] Weigh each raw material according to the mass ratio of dopamine hydrochloride, vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate, emulsifier OP-10, CuSO4 . 5H2O, H2O2 and kaolin of 1:8.3:3.3:7.5:0.42:1.46:2.5 respectively. Then dissolve dopamine hydrochloride in Tris-HCl buffer solution (50 mM, pH = 8.5) to prepare a dopamine hydrochloride solution (concentration: 0.004 g / mL), add vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate and emulsifier OP-10 for emulsification, and then successively add CuSO4 . 5H2O, H2O2 and kaolin, soak at 75 °C for 2.5 h, then wash with deionized water and dry at 60 °C for 3.5 h to obtain modified kaolin.

[0046] This example also provides a preparation method of the above high-performance polyurethane paint, which specifically includes the following steps:

[0047] According to the described weight parts, mix the functional polyurethane prepolymer, modified kaolin, propylene glycol methyl ether acetate, BYK-066N, BYK-300, titanium dioxide 577 and BYK-110 evenly by stirring to obtain the high-performance polyurethane paint.

[0048] Example 2

[0049] A high-performance polyurethane paint is composed of the following components by weight parts: 45 parts of functional polyurethane prepolymer, 4 parts of modified kaolin, 1 part of propylene glycol methyl ether acetate, 0.1 part of BYK-055, 0.2 part of BYK-300, 0.5 part of BYK-103, 10 parts of titanium dioxide 577;

[0050] The preparation steps of the functional polyurethane prepolymer are as follows:

[0051] (1) Prepare the functionalized diol monomer:

[0052] a. Weigh ethylene glycol diglycidyl ether and tetraethylammonium bromide respectively according to a mass ratio of 1:0.01. Then dissolve ethylene glycol diglycidyl ether and tetraethylammonium bromide in dichloromethane, and add them to a high-pressure reactor, where the concentration of ethylene glycol diglycidyl ether in dichloromethane is controlled to be 0.25 mg / mL. Then, under nitrogen protection, CO2 is introduced into the reactor until the pressure in the reactor reaches 4.0 MPa, and the reactants are stirred at 110 °C for 26 h. Then the reactor is cooled to room temperature, and the remaining CO2 is released and the pressure is reduced to atmospheric pressure. The obtained crude product is washed with dichloromethane and dried in a vacuum oven at 30 °C for 24 h to obtain an intermediate product.

[0053] b. Weigh the intermediate product and 7-amino[1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylic acid respectively according to a mass ratio of 1:0.6. Add the intermediate product and 7-amino[1,2,4]triazolo[1,5-a]pyrimidine-6-carboxylic acid to dimethyl sulfoxide, where the concentration of the intermediate product in dimethyl sulfoxide is 0.05 g / mL. Under a nitrogen atmosphere, after reacting at 60 °C for 24 h, the reactants are precipitated with ice ether and washed 3 times, and then dried in a vacuum oven at 40 °C for 48 h to obtain a functionalized diol monomer. The 1H NMR of the functionalized diol monomer is consistent with that of Example 1. 1 The 1H NMR of the functionalized diol monomer is consistent with that of Example 1.

[0054] (2)Weigh polytetrahydrofuran diol, toluene diisocyanate and the functionalized diol monomer respectively according to a molar ratio of 1:2.5:0.3. Then mix polytetrahydrofuran diol, toluene diisocyanate and dibutyltin dilaurate, where the amount of dibutyltin dilaurate is 0.05% of the total mass of polytetrahydrofuran diol and toluene diisocyanate. Under a N2 atmosphere, react at 75 °C for 3 h, and then add the functionalized diol monomer and react for 4 h to obtain a functional polyurethane prepolymer.

[0055] The preparation method of the modified kaolin is as follows:

[0056] Weigh each raw material respectively according to a mass ratio of hydrochloric acid dopamine, vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate, emulsifier OP-10, CuSO4·5H2O, H2O2 and kaolin of 1:8.5:3.25:6.5:0.4:1.375:2. Then dissolve hydrochloric acid dopamine in Tris-HCl buffer solution (50 mM, pH = 8.5) to prepare a hydrochloric acid dopamine solution (concentration is 0.004 g / mL), and then add vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate and emulsifier OP-10 to fully emulsify. Then, add CuSO4·5H2O, H2O2 and kaolin in turn, soak at 75 °C for 3 h, and then wash with deionized water and dry at 60 °C for 4 h to obtain modified kaolin. . Weigh each raw material respectively according to a mass ratio of hydrochloric acid dopamine, vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate, emulsifier OP-10, CuSO4·5H2O, H2O2 and kaolin of 1:8.5:3.25:6.5:0.4:1.375:2. Then dissolve hydrochloric acid dopamine in Tris-HCl buffer solution (50 mM, pH = 8.5) to prepare a hydrochloric acid dopamine solution (concentration is 0.004 g / mL), and then add vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate and emulsifier OP-10 to fully emulsify. Then, add CuSO4·5H2O, H2O2 and kaolin in turn, soak at 75 °C for 3 h, and then wash with deionized water and dry at 60 °C for 4 h to obtain modified kaolin. . Soak at 75 °C for 3 h, and then wash with deionized water and dry at 60 °C for 4 h to obtain modified kaolin.

[0057] This embodiment also provides a preparation method of the above high-performance polyurethane paint, which is the same as that in Embodiment 1.

[0058] Embodiment 3

[0059] A high-performance polyurethane paint is composed of the following components by weight: 60 parts of functional polyurethane prepolymer, 7 parts of modified kaolin, 3 parts of propylene glycol methyl ether acetate, 0.5 part of BYK-057, 0.6 part of BYK-300, 1 part of BYK-110, and 15 parts of titanium dioxide 577;

[0060] The preparation steps of the functional polyurethane prepolymer are as follows:

[0061] (1) Preparation of functionalized diol monomer:

[0062] a. Weigh ethylene glycol diglycidyl ether and tetraethylammonium bromide according to a mass ratio of 1:0.015 respectively, then dissolve ethylene glycol diglycidyl ether and tetraethylammonium bromide in dichloromethane, and add them into a high-pressure reaction kettle, where the concentration of ethylene glycol diglycidyl ether in dichloromethane is controlled to be 0.25 mg / mL; then add CO2 to the reaction kettle under nitrogen protection until the pressure in the reactor reaches 4.0 MPa, stir the reactants at 130 °C for 22 h, then cool the reaction kettle to room temperature, release the remaining CO2 and reduce the pressure to atmospheric pressure, wash the obtained crude product with dichloromethane, and dry it in a vacuum oven at 30 °C for 24 h to obtain an intermediate product;

[0063] b. Weigh the intermediate product and 7-amino[1,2,4]triazolo[1,5-A]pyrimidine-6-carboxylic acid according to a mass ratio of 1:1.5 respectively, add the intermediate product and 7-amino[1,2,4]triazolo[1,5-A]pyrimidine-6-carboxylic acid into dimethyl sulfoxide, where the concentration of the intermediate product in dimethyl sulfoxide is 0.05 g / mL; under a nitrogen atmosphere, react at 80 °C for 18 h, then precipitate and wash the reactants with ice ether 3 times, and dry them in a vacuum oven at 40 °C for 48 h to obtain the functionalized diol monomer. The 1H NMR of the functionalized diol monomer is consistent with that in Embodiment 1. 1 The 1H NMR is consistent with that in Embodiment 1.

[0064] (2) Weigh polytetrahydrofuran diol, hexamethylene diisocyanate and functionalized diol monomer according to a molar ratio of 1:4:0.8 respectively; then mix polytetrahydrofuran diol, hexamethylene diisocyanate and dibutyltin dilaurate, where the dosage of dibutyltin dilaurate is 0.2% of the total mass of polytetrahydrofuran diol and hexamethylene diisocyanate, react at 85 °C for 1 h under an N2 atmosphere, and then add the functionalized diol monomer and react for 2 h to obtain the functional polyurethane prepolymer.

[0065] The preparation method of the modified kaolin is as follows:

[0066] According to dopamine hydrochloride, vinyl (trifluoromethyl) dimethyl silane, sodium dodecyl sulfate, emulsifier OP-10, CuSO4 . The mass ratio of 5H2O, H2O2 and kaolin is 1:8.4:3.4:6.6:0.45:1.1:1.5. Each raw material is weighed separately, and then dopamine hydrochloride is dissolved in Tris-HCl buffer (50mM, pH=8.5) to prepare dopamine hydrochloride solution (concentration is 0.004g / mL), and then vinyl (trifluoromethyl) dimethylsilane, sodium dodecyl sulfate and emulsifier OP-10 are added to fully emulsify, and then CuSO4·5H2O, H2O2 and kaolin are added in sequence. The mixture is soaked at 75℃ for 3h, and then washed with deionized water and dried at 60℃ for 3h to obtain modified kaolin.

[0067] This embodiment also provides a method for preparing the above-mentioned high-performance polyurethane paint, which is the same as that of Example 1.

[0068] Comparative Example 1

[0069] This comparative example 1 is basically the same as Example 1, except that the modified kaolin is replaced by kaolin, and the rest is the same as Example 1.

[0070] Comparative Example 2

[0071] Comparative Example 2 is basically the same as Example 1, except that in the preparation process of the modified kaolin, the step of adding vinyl (trifluoromethyl) dimethyl silane, sodium dodecyl sulfate and emulsifier OP-10 for sufficient emulsification is omitted, and the rest is consistent with Example 1.

[0072] Comparative Example 3

[0073] Comparative Example 3 is basically the same as Example 1, except that step (1) is omitted in the preparation process of the functional polyurethane prepolymer, and the addition of the functionalized diol monomer is omitted in step (2). The rest is the same as Example 1.

[0074] Test example

[0075] In order to characterize the performance of the high-performance polyurethane paint coatings prepared in the above Examples 1-3 and Comparative Examples 1-3, the following tests were performed:

[0076] (1) Storage stability test is evaluated according to the following standards:

[0077] Store the high-performance polyurethane paint in a dark place at 25°C for 6 months and observe whether there is any agglomeration or delamination.

[0078] The coatings of the above groups were evenly coated on the substrate of tinplate. After curing and drying, the following tests were carried out:

[0079] (2)The adhesion was tested according to the test standard of GB / T 5210-2006;

[0080] (3)The antibacterial and mildew-proof performance was tested according to the test standard of GB / T 21866-2008 "Determination Method and Antibacterial Effect of Antibacterial Coatings (Film Coating)". Escherichia coli and Staphylococcus aureus were selected for the test of antibacterial performance; the evaluation criteria are shown in Table 1.

[0081] (4)The water contact angle was tested using a contact angle measuring instrument. During the test, the droplet size was set to 3 μL / drop.

[0082] (5)The mechanical properties were tested according to the test standard of GB / T 1040.1-2018. The tensile rate was 10 mm / min, and the specimen was dumbbell-shaped.

[0083] The test results obtained from the above groups were recorded in Table 2.

[0084] Table 1 Evaluation Criteria for Antibacterial Performance

[0085]

[0086] Table 2

[0087]

[0088] It can be clearly seen from the test data in Table 2 that the high-performance polyurethane paints prepared in Examples 1-3 of the present invention have better antibacterial and mildew-proof performance, water-proof and self-cleaning performance, mechanical properties and storage stability. Among them, the antibacterial rate of the coatings prepared in Examples 1-3 against Escherichia coli can reach 98.6%, and the antibacterial rate against Staphylococcus aureus can reach 98.2%, and the antibacterial grade can reach Grade I. The water contact angle can reach 158°, with a super-hydrophobic surface, enabling self-cleaning. In addition, the functional polyurethane prepolymer in the present invention also affects the mechanical properties and storage stability of the material to a certain extent. Examples 1-3 are significantly higher than Comparative Examples 1-3. After 6 months of storage, no precipitation and stratification phenomena have occurred in the above coatings.

[0089] Compared with Example 1, in Comparative Example 1, the modified kaolin was replaced with kaolin. In Comparative Example 2, the step of adding vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate and emulsifier OP-10 for sufficient emulsification was omitted during the preparation of the modified kaolin. In Comparative Example 3, the addition of the functionalized diol monomer was omitted during the process of the functional polyurethane prepolymer. The coatings obtained in Comparative Examples 1-3 showed varying degrees of decline in antibacterial and mildew-proof performance, waterproof and self-cleaning performance, mechanical properties and storage stability. The above experimental results show that both the functionalized diol monomer and the modified kaolin have certain effects on the performance of the coating. Specifically, due to the presence of the antibacterial active triazolopyrimidine structure and carboxylic acid group in the structure of the functionalized diol monomer, after being introduced into the polyurethane chain segment through copolymerization reaction, it can significantly improve the antibacterial and mildew-proof performance and mechanical properties of the coating. At the same time, the introduction of the carboxylic acid group can also improve the storage stability of the polyurethane coating. In the modified kaolin added to the coating in the present invention, due to the introduction of the extremely low surface energy trifluoromethyl (-CF3), the waterproof and self-cleaning performance of the coating is greatly enhanced; on the other hand, the polydopamine in the modified kaolin contains copper ions and catechol groups, forming a metal-phenol network, which can not only improve the dispersibility of kaolin, but also further enhance the stability and antibacterial property of the coating.

[0090] The above content is only an example and illustration of the concept of the present invention. Those skilled in the art of the present technology making various modifications or supplements to the described specific embodiments or using similar methods for substitution all fall within the scope of protection required by the present invention.

Claims

1. A high-performance polyurethane paint, characterized in that, By weight parts, it includes the following raw materials: 45 - 60 parts of functional polyurethane prepolymer, 4 - 7 parts of modified kaolin, 1 - 3 parts of propylene glycol methyl ether acetate, 0.1 - 0.5 part of defoamer, 0.2 - 0.6 part of leveling agent, 10 - 15 parts of titanium dioxide, and 0.5 - 1 part of dispersant; The preparation steps of the modified kaolin are as follows: Add vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate and an emulsifier to the dopamine hydrochloride solution for emulsification, and then add CuSO4 . 5H2O, H2O2 and kaolin for soaking treatment, collect the product, wash and dry it to obtain the product; The preparation steps of the functional polyurethane prepolymer are as follows: (1)Prepare a functionalized diol monomer; the specific steps are as follows: a. Under an inert gas atmosphere, introduce CO2 into the mixed solution of ethylene glycol diglycidyl ether and tetraethylammonium bromide until the pressure reaches 4 - 5 MPa, and carry out a heating reaction. After the reaction is completed, collect the crude product and wash and dry it to obtain an intermediate product; b. Add the intermediate product and 7 - amino[1,2,4]triazolo[1,5 - A]pyrimidine - 6 - carboxylic acid to a solvent for heating reaction, precipitate and wash the reactant with ice ether, and then dry it to obtain the functionalized diol monomer; (2)Mix polytetrahydrofuran diol, diisocyanate, and dibutyltin dilaurate for the first reaction, and then add the functionalized diol monomer for the second reaction to obtain the functional polyurethane prepolymer.

2. The high-performance polyurethane paint according to claim 1, characterized in that, In step (2), the molar ratio of polytetrahydrofuran diol, diisocyanate, and functionalized diol monomer is 1:(2.5 - 4):(0.3 - 0.8); the dosage of dibutyltin dilaurate is 0.05 - 0.2% of the total weight of polytetrahydrofuran diol and diisocyanate.

3. The high-performance polyurethane paint according to claim 1, characterized in that, In step (2), the temperature of the first reaction is 75 - 85 °C, and the time is 1 - 3 h; the temperature of the second reaction is 75 - 85 °C, and the time is 2 - 4 h.

4. The high-performance polyurethane paint according to claim 1, characterized in that, In step a, the mass ratio of ethylene glycol diglycidyl ether to tetraethylammonium bromide is 1:0.01 - 0.015; the temperature of the heating reaction is 110 - 130 °C, and the time is 22 - 26 h.

5. The high-performance polyurethane paint according to claim 1, wherein In step b, the mass ratio of the intermediate product to 7 - amino[1,2,4]triazolo[1,5 - A]pyrimidine - 6 - carboxylic acid is 1:0.6 - 1.5, the temperature of the heating reaction is 60 - 80 °C, and the time is 18 - 24 h.

6. The high-performance polyurethane paint according to claim 1, characterized in that, The mass ratio of dopamine hydrochloride, vinyl(trifluoromethyl)dimethylsilane, sodium dodecyl sulfate, emulsifier, CuSO4 . 5H2O, H2O2 and kaolin is 1:(8.3 - 8.5):(3.25 - 3.4):(6.5 - 7.5):(0.4 - 0.45):(1.1 - 1.46):(1.5 - 2.5).

7. The high-performance polyurethane paint according to claim 1, characterized in that, The temperature of the soaking treatment is 70 - 80 °C, and the time is 2 - 3 h.

8. The preparation method of the high-performance polyurethane paint according to any one of claims 1-7, characterized in that, It includes the following steps: according to the above weight ratio, mix and stir evenly the functional polyurethane prepolymer, modified kaolin, defoamer, propylene glycol methyl ether acetate, dispersant, titanium dioxide, and leveling agent to obtain a high - performance polyurethane paint.

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