A high performance spray paint and preparation method thereof

Abstract

The present invention belongs to the field of coating technology, and in particular to a high-performance spray paint and a preparation method thereof. The high-performance spray paint provided by the present invention includes 70-80 parts of modified acrylic emulsion, 5-10 parts of leveling agent, 10-15 parts of defoamer, 20-30 parts of nanofiller, 15-20 parts of sodium oleate and 120-130 parts of water. The high-performance spray paint of the present invention adopts a water-soluble acrylic resin of a self-crosslinking core-shell structure, so that the modified acrylic emulsion system produces physical crosslinking, effectively improves the hardness and impact resistance of the paint film, and by adjusting the formula composition of the high-performance spray paint, by adding components such as nanofiller, diacetone acrylamide, oxalyl hydrazide, the wear resistance and weather resistance of the coating are significantly improved.

Description

Technical Field

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

[0002] Automotive coatings not only require good gloss and color retention, but also high hardness, good water resistance and good acid resistance. In addition, as an indispensable material in modern industry, the research and application of environmentally friendly components of high-performance coatings are gradually becoming an important trend in the development of the industry. The coatings industry is also facing the challenge of transformation and upgrading. The research and development and promotion of environmentally friendly coatings have become an inevitable choice for the industry.

[0003] There are many types of existing automotive coatings. Currently, most of the automotive manufacturing industry uses solvent-based automotive paints, which contain a large amount of substances that are harmful to the human body and the environment. During the production and spraying process, the evaporation of solvents will cause air pollution and safety hazards, which is not in line with the concept of green production. Compared with traditional solvent-based automotive paints, water-based automotive paints have incomparable advantages. They use water as a solvent, have ultra-low VOC content, and have less impact on the environment and human health; they have a short flash-drying time and dry quickly, which can greatly improve production efficiency. However, the water-based environmentally friendly coatings in the prior art generally have technical problems such as poor film adhesion, low impact strength, poor wear resistance and weather resistance.

[0004] The Chinese patent application with publication number CN105295629A discloses a high-gloss water-based automotive paint, whose formula includes tricresyl phosphate, α-lipoic acid, trimer isocyanate, water-based ethyl methacrylate resin, water-based methyl etherified amino resin, water-based polyurethane leveling agent, deionized water, and propylene glycol as a low-temperature film-forming aid. Compared with the drying conditions of traditional coatings, this type of automotive paint saves more than 50% of time and improves production efficiency. The paint film is smooth and has a soft gloss, which can prolong the fading time of the paint surface. However, it does not improve the problems of poor adhesion of the paint film, poor impact resistance, and poor storage stability.

[0005] The Chinese patent application with publication number CN115073992A discloses an ultra-thin water-based anti-stone-smash coating for automobile chassis and its preparation method, wherein the formula components are: 15.0-20.0wt% of phosphoric acid-modified epoxy resin, 17.0-23.0wt% of methanol isopropanol mixed etherified N-hydroxymethyl acrylamide resin, 0.5-1.0wt% of bentonite, 3.0-5.0wt% of carbon black, 2.0-5.0wt% of dipropylene glycol butyl ether, 0.5-1.0wt% of water-based substrate wetting agent, 0.5-1.0wt% of water-based polysiloxane defoamer, 30.0-40.0wt% of calcium carbonate, and 4.0-31.5wt% of deionized water. This ultra-thin water-based anti-stone-smash coating for automobile chassis is sprayed on the chassis and fenders of the automobile, and the anti-stone-smash performance and anti-corrosion performance of the paint film are better than other paint films under the same conditions. Summary of the invention

[0006] In view of the technical problems of poor adhesion, low impact strength, poor wear resistance and weather resistance of water-based automobile spray paint in the prior art, the purpose of the present invention is to provide a high-performance spray paint and a preparation method thereof.

[0007] In order to achieve the above object, the technical solution of the present invention is as follows:

[0008] A high-performance spray paint comprising the following components and their weight proportions:

[0009] 70-80 parts of modified acrylic emulsion, 5-10 parts of leveling agent, 10-15 parts of defoaming agent, 20-30 parts of nano filler, 15-20 parts of sodium oleate, and 120-130 parts of water;

[0010] The preparation method of the modified acrylic emulsion comprises: (1) adding deionized water and an emulsifier into a reaction kettle, stirring, introducing nitrogen, heating, adding a part of the pre-emulsified core monomer and a part of the ammonium persulfate aqueous solution, reacting until the system temperature drops, continuing to heat, dripping the remaining pre-emulsified core monomer and the ammonium persulfate aqueous solution, and keeping the temperature to react to obtain a core emulsion; (2) dripping the pre-emulsified shell monomer and the ammonium persulfate aqueous solution into the core emulsion obtained in step (1), keeping the temperature to react, adding ammonia water to adjust the pH value after cooling, adding oxalic acid dihydrazide aqueous solution, stirring evenly, filtering, and obtaining a modified acrylic emulsion.

[0011] The high-performance spray paint of the present invention adopts a water-soluble acrylic resin with a self-crosslinking core-shell structure and a film-forming principle at the micron-level small molecule level. As the paint film dries, the crosslinking functional groups in the adjacent polymers undergo physical and chemical aggregation, so that the modified acrylic emulsion system produces physical crosslinking. After film formation, the film structure contains a large number of microphases, which significantly improves the hardness and impact resistance of the film. The addition of nanofillers can significantly improve the wear resistance and weather resistance of the coating.

[0012] In the preparation process of the core emulsion, firstly, part of the pre-emulsified core monomer and part of the initiator ammonium persulfate are reacted to generate core particles. This process is an exothermic reaction. The system temperature will increase as the reaction proceeds. When the temperature of the reaction system drops, it means that part of the pre-emulsified core monomer has reacted completely. At this time, the temperature continues to rise, and then the remaining pre-emulsified core monomer and initiator ammonium persulfate are added dropwise. The reaction will proceed on the surface of the core particles, making the core particles larger. After the reaction is completed, the core emulsion is obtained. The pre-emulsified shell emulsion and the initiator ammonium persulfate are continued to be added dropwise to the core emulsion, so that the pre-emulsified shell emulsion continues to react on the core particles, and finally a self-crosslinking water-soluble acrylic resin emulsion with a core-shell structure is obtained.

[0013] The leveling agent and defoaming agent described in the present invention are conventional commercially available leveling agents and defoaming agents in the coating field.

[0014] Furthermore, the preparation method of the pre-emulsified core monomer is: evenly mix deionized water and an emulsifier, slowly add ethyl methacrylate, acrylonitrile, acrylic acid, and sodium vinyl sulfonate, emulsify, and obtain a pre-emulsified core monomer; the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, and sodium vinyl sulfonate is 7-11:3-6:13-15:5-8. The preparation method of the pre-emulsified shell monomer is: evenly mix deionized water and an emulsifier, slowly add ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate, and diacetone acrylamide, emulsify, and obtain a pre-emulsified shell monomer; the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate, and diacetone acrylamide is 11-15:7-9:10-14:3-6:8-11.

[0015] In the present invention, the glass transition temperature (Tg) of the modified acrylic resin is controlled by controlling the mass ratio of each reactive monomer, thereby controlling the hardness and brittleness of the film layer formed by the modified acrylic resin. When the Tg value becomes low, the hardness of the film layer formed by the prepared acrylic resin is low, and the wear resistance and weather resistance are poor. When the Tg value increases, the hardness of the film layer formed by the prepared acrylic resin is improved, but the brittleness increases at the same time, which is not conducive to improving the adhesion and impact resistance of the film layer. In addition, the ketone carbonyl group in the molecular structure of diacetone acrylamide can react with the hydrazide group in oxalyl dihydrazide to increase the crosslinking degree of the polymer, thereby improving the wear resistance and weather resistance of the paint film.

[0016] Furthermore, in the step (1) of the method for preparing the modified acrylic emulsion, the emulsifier is one of sorbitan fatty acid, poloxamer, sodium lauryl sulfate and sodium oleate.

[0017] Furthermore, in the preparation method of the modified acrylic emulsion, the heating temperature in step (1) is 73-77°C, and the temperature of continued heating is 80-85°C; the mass percentage of the ammonium persulfate aqueous solution in step (1) and step (2) is 13-15%, and the cooling temperature in step (2) is 30-40°C.

[0018] Furthermore, in the preparation method of the modified acrylic emulsion, the amount of the part of the pre-emulsified core monomer in step (1) is 5-8% of the total mass of the pre-emulsified core monomer; the amount of the part of the ammonium persulfate aqueous solution is 10-15% of the total mass of the ammonium persulfate aqueous solution; in step (2), the pH value of the ammonia water is adjusted to 8-9, and the mass percentage of the oxalic acid dihydrazide aqueous solution is 15-20%.

[0019] Furthermore, in the preparation method of the modified acrylic emulsion, the dripping time of the remaining pre-emulsified core monomer and the aqueous ammonium persulfate solution in step (1) is controlled within 1.5 hours, and the insulation reaction time is 1-1.5 hours; the dripping time of the pre-emulsified shell monomer and the aqueous ammonium persulfate solution in step (2) is controlled within 2 hours, the insulation reaction time is 2-2.5 hours, and the filtration filter is 800 mesh.

[0020] Furthermore, the mass fractions of the components in step (1) of the preparation method of the modified acrylic emulsion are: 50-60 parts of deionized water, 15-20 parts of emulsifier, 20-30 parts of pre-emulsified core monomer, and 10-20 parts of ammonium persulfate aqueous solution; the mass fractions of the components in step (2) are: 40-50 parts of pre-emulsified shell monomer, 20-25 parts of ammonium persulfate aqueous solution, and 15-20 parts of oxalyl dihydrazide aqueous solution.

[0021] Furthermore, the nano filler in the high-performance spray paint is one of nano titanium dioxide, nano calcium carbonate and nano kaolin.

[0022] The present invention also provides a method for preparing the high-performance spray paint, which specifically comprises: mixing the modified acrylic emulsion with water, stirring evenly, adding a leveling agent and a defoamer, stirring evenly, and then adding nano fillers and sodium oleate, stirring evenly to obtain the high-performance spray paint.

[0023] Compared with the prior art, the high-performance spray paint and preparation method thereof provided by the present invention have the following technical advantages:

[0024] (1) The paint film formed by the high-performance spray paint prepared in the present invention has good adhesion. The water-soluble acrylic resin with a self-crosslinking core-shell structure is used in the formula, so that the modified acrylic emulsion system produces physical crosslinking, which effectively improves the hardness and impact resistance of the paint film.

[0025] (2) In the present invention, the wear resistance and weather resistance of the coating are significantly improved by adjusting the formula composition of the high-performance spray paint and adding components such as nanofillers, diacetone acrylamide, and oxalic acid hydrazide.

[0026] (3) The high-performance spray paint of the present invention is not prone to stratification and precipitation during long-term storage and has good uniformity and stability. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with specific embodiments, but the present invention is not limited to the following embodiments. Those skilled in the art can make various modifications based on the basic idea of ​​the present invention, but as long as they do not deviate from the basic idea of ​​the present invention, they are all within the scope of the present invention.

[0028] The leveling agent in this embodiment is purchased from Foshan Nuoyu New Material Technology Co., Ltd., product model L-718; the defoaming agent is purchased from Guangdong Nanhui New Material Co., Ltd., product model CI-1771. The particle size of the nanofiller in this embodiment is 100-200nm.

[0029] Example 1

[0030] A high-performance spray paint comprising the following components and their weight proportions:

[0031] 75 parts of modified acrylic emulsion, 8 parts of leveling agent, 12 parts of defoaming agent, 25 parts of nano calcium carbonate, 17 parts of sodium oleate, and 126 parts of water;

[0032] The preparation method of the modified acrylic emulsion is as follows: (1) adding 55 parts of deionized water and 18 parts of sodium oleate into a reaction kettle, stirring, introducing nitrogen, heating to 75° C., adding 1.5 parts of pre-emulsified core monomer and 3 parts of 14% by mass ammonium persulfate aqueous solution, reacting until the system temperature drops, continuing to heat to 83° C., and dripping 18.5 parts of pre-emulsified core monomer and 17 parts of 14% by mass ammonium persulfate aqueous solution, and controlling the dripping time to be within 1.5 hours. , keep warm for 1.2 hours to obtain a core emulsion; (2) add 45 parts of pre-emulsified shell monomer and 23 parts of 14% by mass ammonium persulfate aqueous solution to the core emulsion obtained in step (1), control the dropwise addition time to be within 2 hours, keep warm for 2.2 hours, cool to 35°C, add ammonia water to adjust the pH value to 8.5, add 18 parts of 18% by mass oxalyl dihydrazide aqueous solution, stir evenly, filter with an 800 mesh filter to obtain a modified acrylic emulsion. The preparation method of the pre-emulsified core monomer is: mix 35 parts of deionized water and 7 parts of sodium oleate evenly, slowly add ethyl methacrylate, acrylonitrile, acrylic acid, and sodium vinyl sulfonate, emulsify, and obtain a pre-emulsified core monomer; the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, and sodium vinyl sulfonate is 9:7:14:7. The preparation method of the pre-emulsified shell monomer is as follows: 35 parts of deionized water and 7 parts of sodium oleate are evenly mixed, ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide are slowly added, and emulsified to obtain the pre-emulsified shell monomer; the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide is 13:8:12:5:10.

[0033] The preparation method of the high-performance spray paint specifically comprises: mixing the modified acrylic emulsion with water, stirring evenly, adding a leveling agent and a defoamer, stirring evenly, and then adding nano fillers and sodium oleate, stirring evenly, to obtain the high-performance spray paint.

[0034] Example 2

[0035] A high-performance spray paint comprising the following components and their weight proportions:

[0036] 70 parts of modified acrylic emulsion, 5 parts of leveling agent, 10 parts of defoaming agent, 20 parts of nano titanium dioxide, 15 parts of sodium oleate, and 130 parts of water;

[0037] The preparation method of the modified acrylic emulsion is as follows: (1) adding 60 parts of deionized water and 15 parts of fatty acid sorbitan into a reaction kettle, stirring, introducing nitrogen, heating to 73° C., adding 1.6 parts of pre-emulsified core monomer and 2 parts of 13% by mass ammonium persulfate aqueous solution, reacting until the system temperature drops, continuing to heat to 80° C., and dripping 18.4 parts of pre-emulsified core monomer and 18 parts of 13% by mass ammonium persulfate aqueous solution, and controlling the dripping time to 1:1. 1.5 hours or less, keep warm for 1 hour to obtain a core emulsion; (2) add 40 parts of pre-emulsified shell monomer and 20 parts of 13% by mass ammonium persulfate aqueous solution to the core emulsion obtained in step (1), control the dropwise addition time to be within 2 hours, keep warm for 2 hours, cool to 30°C, add ammonia water to adjust the pH value to 8, add 15 parts of 15% by mass oxalyl dihydrazide aqueous solution, stir evenly, filter with an 800 mesh filter to obtain a modified acrylic emulsion. The preparation method of the pre-emulsified core monomer is as follows: 30 parts of deionized water and 5 parts of fatty acid sorbitan are mixed evenly, ethyl methacrylate, acrylonitrile, acrylic acid, and sodium vinyl sulfonate are slowly added, emulsified, and a pre-emulsified core monomer is obtained; the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, and sodium vinyl sulfonate is 7:3:13:5. The preparation method of the pre-emulsified shell monomer is as follows: 30 parts of deionized water and 5 parts of fatty acid sorbitan are uniformly mixed, ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide are slowly added, and emulsified to obtain the pre-emulsified shell monomer; the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide is 11:7:10:3:8.

[0038] The preparation method of the high-performance spray paint specifically comprises: mixing the modified acrylic emulsion with water, stirring evenly, adding a leveling agent and a defoamer, stirring evenly, and then adding nano fillers and sodium oleate, stirring evenly, to obtain the high-performance spray paint.

[0039] Example 3

[0040] A high-performance spray paint comprising the following components and their weight proportions:

[0041] 80 parts of modified acrylic emulsion, 10 parts of leveling agent, 15 parts of defoaming agent, 30 parts of nano kaolin, 20 parts of sodium oleate, and 120 parts of water;

[0042] The preparation method of the modified acrylic emulsion is as follows: (1) adding 50 parts of deionized water and 20 parts of sodium dodecyl sulfate into a reaction kettle, stirring, introducing nitrogen, heating to 77° C., adding 1 part of pre-emulsified core monomer and 1 part of 15% by mass ammonium persulfate aqueous solution, reacting until the system temperature drops, continuing to heat to 85° C., and dripping 19 parts of pre-emulsified core monomer and 9 parts of 15% by mass ammonium persulfate aqueous solution, and controlling the dripping time to 1.5 h. The pre-emulsified core monomer is prepared by mixing 40 parts of deionized water and 9 parts of sodium dodecyl sulfate, and then slowly adding ethyl methacrylate, acrylonitrile, acrylic acid and sodium vinyl sulfonate to obtain a pre-emulsified core monomer. The mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid and sodium vinyl sulfonate is 11:6:15:8. The preparation method of the pre-emulsified shell monomer is as follows: 40 parts of deionized water and 9 parts of sodium dodecyl sulfate are uniformly mixed, ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide are slowly added, and emulsified to obtain the pre-emulsified shell monomer; the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide is 15:9:14:6:11.

[0043] The preparation method of the high-performance spray paint specifically comprises: mixing the modified acrylic emulsion with water, stirring evenly, adding a leveling agent and a defoamer, stirring evenly, and then adding nano fillers and sodium oleate, stirring evenly, to obtain the high-performance spray paint.

[0044] Comparative Example 1

[0045] The high-performance spray paint and its preparation method described in this comparative example are similar to those in Example 1. The difference between this comparative example and Example 1 is that the modified acrylic emulsion described in this comparative example is prepared according to paragraphs

[0038] to

[0050] of the specification of Chinese patent ZL202311458007.3.

[0046] Comparative Example 2

[0047] The high-performance spray paint and its preparation method described in this comparative example are similar to those in Example 1. The difference between this comparative example and Example 1 is that the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide described in the preparation method of the pre-emulsified shell monomer in this comparative example is 4:15:2:13:5.

[0048] Comparative Example 3

[0049] The high-performance spray paint and its preparation method described in this comparative example are similar to those in Example 1. The difference between this comparative example and Example 1 is that an equal amount of adipic acid dihydrazide is used instead of oxalic acid dihydrazide in the preparation method of the modified acrylic emulsion in this comparative example.

[0050] Comparative Example 4

[0051] The high-performance spray paint and its preparation method described in this comparative example are similar to those in Example 1. The difference between this comparative example and Example 1 is that an equal amount of methyl methacrylate is used instead of ethyl methacrylate in the preparation method of the pre-emulsified core monomer and the pre-emulsified shell monomer in this comparative example.

[0052] Comparative Example 5

[0053] The high-performance spray paint and its preparation method described in this comparative example are similar to those in Example 1. The difference between this comparative example and Example 1 is that an equal amount of methyl acrylate is used instead of acrylic acid in the preparation method of the pre-emulsified core monomer and the pre-emulsified shell monomer in this comparative example.

[0054] Comparative Example 6

[0055] The high-performance spray paint and its preparation method described in this comparative example are similar to those in Example 1. The difference between this comparative example and Example 1 is that an equal amount of acrylamide is used instead of diacetone acrylamide in the preparation method of the pre-emulsified shell monomer in this comparative example.

[0056] Test example

[0057] Adhesion grade test: According to GB / T 9286-2021 "Scratch test for paints and varnishes", the paint films formed by the high-performance spray paints prepared in Examples 1 to 3 and Comparative Examples 1 to 6 were tested for adhesion grade;

[0058] Impact strength test: According to GB / T 1732-2020 "Determination of impact resistance of paint film", the paint films formed by the high-performance spray paints prepared in Examples 1 to 3 and Comparative Examples 1 to 6 were tested for impact strength;

[0059] Abrasion resistance test: According to GB / T 1768-2006 "Determination of abrasion resistance of paints and varnishes - Rotating rubber grinding wheel method", the paint films formed by the high-performance spray paints prepared in Examples 1 to 3 and Comparative Examples 1 to 6 were subjected to abrasion resistance test;

[0060] Weather resistance: The paint films formed by the high-performance spray paints prepared in Examples 1 to 3 and Comparative Examples 1 to 6 were tested for weather resistance in accordance with GB / T 1865-2009 “Artificial weathering and artificial radiation exposure of paints and varnishes to filtered xenon lamp radiation”.

[0061] The test results are shown in Table 1.

[0062] Table 1 Performance test results

[0063]

[0064] As shown in Table 1, the paint films formed by the high-performance spray paints prepared in Examples 1 to 3 have an adhesion grade of 0-1 and an impact strength of 75-83 kg / cm 2 , abrasion resistance>210 times, gloss loss rate of xenon lamp aging for ≥1200h<4%, which shows that the paint film formed by the high-performance spray paint provided by the present invention has good adhesion, impact resistance, abrasion resistance and aging resistance, among which the high-performance spray paint prepared in Example 1 has the best performance in all aspects and is the best embodiment of the present invention.

[0065] Compared with Example 1, the modified acrylic emulsion in Comparative Example 1 is a self-crosslinking acrylic emulsion rather than a self-crosslinking core-shell structure acrylic emulsion, but the adhesion grade and impact resistance of the paint film are significantly reduced, which shows that the modified acrylic emulsion with a core-shell structure in the present invention can effectively improve the hardness and impact resistance of the paint film; Comparative Example 2 changes the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide in the preparation method of the pre-emulsified shell monomer, but the adhesion grade, impact resistance, wear resistance and weather resistance of the prepared paint film are reduced to varying degrees, which shows that the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide in the present invention is one of the keys to controlling the performance of high-performance spray paint; In Comparative Example 3, an equal amount of adipic acid dihydrazide is used instead of oxalic acid hydrazide, but the wear resistance of the prepared paint film is The adhesion and weather resistance of the paint film deteriorate, which indicates that not all organic substances containing hydrazide groups can achieve the technical effect of oxalohydrazide; in Comparative Example 4, an equal amount of methyl methacrylate is used instead of ethyl methacrylate, but the adhesion and impact resistance of the prepared paint film decrease, which is because the Tg value of methyl methacrylate is higher than that of ethyl methacrylate, the hardness of the paint film is improved, but the brittleness is increased, resulting in reduced adhesion and impact resistance of the paint film; in Comparative Example 5, an equal amount of methyl acrylate is used instead of acrylic acid, but the wear resistance and weather resistance of the prepared paint film deteriorate, which is due to the Tg value of methyl acrylate being lower than that of acrylic acid; in Comparative Example 6, an equal amount of acrylamide is used instead of diacetone acrylamide, but the wear resistance and weather resistance of the prepared paint film deteriorate, which indicates that diacetone acrylamide can increase the crosslinking degree of the polymer with oxalohydrazide, thereby improving the wear resistance and weather resistance of the paint film.

[0066] The above embodiments are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any person skilled in the art shall not modify the above embodiments without violating the spirit and scope of the present invention. Therefore, any modification, equivalent substitution and improvement made by those skilled in the art under the technical concept of the present invention shall still be covered by the claims of the present invention.

Claims

1. A high performance spray paint, characterized in that: It includes the following components and their weight parts: 70-80 parts of modified acrylic emulsion, 5-10 parts of leveling agent, 10-15 parts of defoaming agent, 20-30 parts of nano filler, 15-20 parts of sodium oleate, and 120-130 parts of water; The preparation method of the modified acrylic emulsion is as follows: (1) adding 50-60 parts of deionized water and 15-20 parts of emulsifier into a reaction kettle, stirring, introducing nitrogen, heating, adding part of the pre-emulsified core monomer and part of the ammonium persulfate aqueous solution, reacting until the system temperature drops, continuing to heat, dropwise adding the remaining pre-emulsified core monomer and the ammonium persulfate aqueous solution, and keeping the temperature for reaction to obtain a core emulsion, wherein the total amount of the pre-emulsified core monomer is 20-30 parts, and the total amount of the ammonium persulfate aqueous solution is 10-20 parts; (2) dropping 40-50 parts of the pre-emulsified shell monomer and 20-25 parts of the ammonium persulfate aqueous solution into the core emulsion obtained in step (1), keeping the temperature for reaction, adding ammonia water to adjust the pH value after cooling, adding 15-20 parts of a 15-20% by mass oxalic acid dihydrazide aqueous solution, stirring evenly, filtering, and obtaining a modified acrylic emulsion; The preparation method of the pre-emulsified core monomer is as follows: deionized water and an emulsifier are uniformly mixed, and ethyl methacrylate, acrylonitrile, acrylic acid, and sodium vinyl sulfonate are slowly added, and emulsified to obtain the pre-emulsified core monomer; the mass ratio of ethyl methacrylate, acrylonitrile, acrylic acid, and sodium vinyl sulfonate is 7-11:3-6:13-15:5-8; The preparation method of the pre-emulsified shell monomer is as follows: deionized water and an emulsifier are uniformly mixed, ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide are slowly added, and emulsification is performed to obtain the pre-emulsified shell monomer; the mass ratio of the ethyl methacrylate, acrylonitrile, acrylic acid, sodium vinyl sulfonate and diacetone acrylamide is 11-15:7-9:10-14:3-6:8-11.

2. The high performance spray paint according to claim 1, characterized in that: The emulsifier in step (1) of the method for preparing modified acrylic emulsion is one of sorbitan fatty acid, poloxamer, sodium lauryl sulfate and sodium oleate.

3. The high performance spray paint according to claim 1, characterized in that: The preparation method of modified acrylic emulsion comprises the following steps: the heating temperature in step (1) is 73-77°C, and the temperature of continued heating is 80-85°C; the mass percentage of the ammonium persulfate aqueous solution in steps (1) and (2) is 13-15%, and the cooling temperature in step (2) is 30-40°C.

4. The high performance spray paint according to claim 1, characterized in that: The amount of the part of the pre-emulsified core monomer in step (1) of the preparation method of the modified acrylic emulsion is 5-8% of the total mass of the pre-emulsified core monomer; the amount of the part of the ammonium persulfate aqueous solution is 10-15% of the total mass of the ammonium persulfate aqueous solution; and the pH value of the ammonia water in step (2) is adjusted to 8-9.

5. The high performance spray paint according to claim 1, characterized in that: The preparation method of modified acrylic emulsion is as follows: in step (1), the dripping time of the remaining pre-emulsified core monomer and the aqueous ammonium persulfate solution is controlled within 1.5 hours, and the insulation reaction time is 1-1.5 hours; in step (2), the dripping time of the pre-emulsified shell monomer and the aqueous ammonium persulfate solution is controlled within 2 hours, the insulation reaction time is 2-2.5 hours, and the filtration filter is 800 mesh.

6. The high performance spray paint according to claim 1, characterized in that: The nano filler in the high-performance spray paint is one of nano titanium dioxide, nano calcium carbonate and nano kaolin.

7. The method for preparing a high-performance spray paint according to any one of claims 1 to 6, characterized in that: Specifically: the modified acrylic emulsion is mixed with water, stirred evenly, a leveling agent and a defoamer are added, and after stirring evenly, nano fillers and sodium oleate are added, and stirred evenly to obtain a high-performance spray paint.

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