An aqueous wear-resistant ceramic heat-insulating coating and its preparation method

Abstract

The invention discloses a water-based wear-resistant ceramic heat-insulating coating and a preparation method thereof, and relates to the field of coatings. The coating comprises the following raw material components by weight: 20-50 parts of a nanoparticle aqueous dispersion, 50-70 parts of a polysiloxane resin, 20-40 parts of an acrylic hydroxyl emulsion, 10-20 parts of an organic solvent, 0.5-1 parts of 2-(2-hydroxyphenyl)-benzotriazole, and 0.5-1 parts of a basic hindered amine. The coating can effectively block the transmission of ultraviolet light and infrared light, and has a significant heat-insulating effect. The coating also has excellent weather resistance, scratch resistance, water resistance and hardness, and has a significant wear-resistant and scratch-resistant protective effect. Meanwhile, the coating has low reflection and scattering effects on visible light and high transmittance to visible light. The coating has excellent heat-insulating effect, good weather resistance, high coating hardness, high visible light transmittance, and low raw material cost, and is suitable for large-scale promotion and use in transparent maintenance structures of buildings.

Description

Technical Field

[0001] The present invention relates to the field of coatings, and in particular to an aqueous wear-resistant ceramic heat-insulating coating and a preparation method thereof. Background Art

[0002] The construction industry is transforming from "quantity seeking" to "quality seeking". Green buildings with "energy conservation and efficiency improvement" are the preferred choice for the construction field. Among them, the heat insulation of building transparent envelope structures has always been a difficult point in the industry. In the early days, curtains were usually used to block sunlight to play a heat insulation role for building transparent envelope structures. Although curtains can block sunlight and play a part of the heat insulation role, after long-term exposure to the sun in summer, the curtains will also store heat and become a heat source. Moreover, blocking sunlight will affect activities inside the building, increase the lighting duration, and waste electricity.

[0003] Currently, for the heat insulation of building transparent envelope structures, polyurethane coatings prepared by nano-indium tin oxide (ITO) and nano-antimony tin oxide (ATO) particles are mainly used. It mainly utilizes the high transparency of nano-indium tin oxide and nano-antimony tin oxide particles in the visible light band (380 - 780nm) and the blocking performance in the infrared band (780 - 2500nm) to achieve the heat insulation effect, which not only satisfies the high light transmittance in most of the visible light band but also isolates most of the energy in the infrared spectral band, playing a certain heat insulation effect.

[0004] In the market, the nano-antimony tin oxide technology is more widely used, while the nano-indium tin oxide technology is less used. This is because the price of nano-indium tin oxide is too expensive, and its high cost severely limits the wide application of the corresponding heat-insulating coating. Moreover, in terms of infrared spectrum blocking, nano-indium tin oxide has the best blocking property only for the infrared band around 1400nm. However, the energy in the infrared band is mainly concentrated in the range of 780 - 1100nm. Therefore, the infrared blocking effect of nano-indium tin oxide for the 780 - 1100nm band is poor, resulting in an unsatisfactory heat insulation effect, and it also has no blocking effect on the ultraviolet band. Although the price of nano-antimony tin oxide is relatively appropriate, in terms of infrared spectrum blocking, nano-antimony tin oxide also has the best blocking property only for the infrared band around 1100nm, and the blocking effect for the infrared band within 1000nm is poor. Therefore, its heat insulation effect is also average, and it also has no blocking effect on the ultraviolet band.

[0005] Meanwhile, existing thermal insulation coatings are generally polyurethane coatings. However, polyurethane coatings not only have a relatively low hardness (generally <2H), are easily scratched, which will affect the transparency of the building's transparent maintenance structure; moreover, the weather resistance of polyurethane coatings is also poor, and problems such as powdering, cracking, and peeling are likely to occur after long-term outdoor exposure, which also seriously affects the user experience and ornamental value of the building's transparent maintenance structure. Therefore, there is an urgent need to develop a coating material with good heat insulation performance, which can effectively block most of the infrared bands, and has low cost and good weather resistance. Summary of the Invention

[0006] The purpose of the present invention is to overcome the problems of poor heat insulation effect and poor weather resistance existing in the heat insulation coatings of existing building transparent maintenance structures, and provide an aqueous wear-resistant ceramic heat insulation coating and its preparation method. The coating formed by this coating not only has high transmittance to visible light, but also has good barrier effects on the ultraviolet band and the infrared band with wavelengths of 780 - 2500 nm; at the same time, it also has the advantages of good weather resistance and high film hardness (hardness > 4H). Therefore, it not only has excellent heat insulation effect, but also can provide good wear-resistant and scratch-proof protection for the building's transparent maintenance structure, which is very in line with the environmental protection concept of low-carbon energy-saving green buildings and is suitable for large-scale popularization and application.

[0007] To achieve the above invention purpose, the present invention provides an aqueous wear-resistant ceramic heat insulation coating, which includes the following raw material components in parts by weight: 20 - 50 parts of nano-particle aqueous dispersion, 50 - 70 parts of polysiloxane resin, 20 - 40 parts of acrylic hydroxy emulsion, 10 - 20 parts of organic solvent, 0.5 - 1 part of 2-(2-hydroxyphenyl)-benzotriazole, and 0.5 - 1 part of alkaline hindered amine;

[0008] Among them, the nano-particle aqueous dispersion contains modified nano-particles with a mass fraction of 20 - 35%, and the modified nano-particles are obtained by modifying nano-particles with a silane coupling agent; the nano-particles are a mixture of nano-antimony-doped tin oxide and nano-tungsten-doped tin oxide with a mass ratio of 1 - 2:5 - 6.

[0009] The present invention relates to an aqueous wear-resistant ceramic heat-insulating coating. By using antimony- and tungsten-doped tin dioxide nanoparticles in combination with 2-(2-hydroxyphenyl)-benzotriazole and basic hindered amines, a synergistic effect is formed, enabling the coating to effectively block the transmission of ultraviolet and infrared light, significantly improving the heat-insulating effect of the coating. Moreover, a polysiloxane resin with a three-dimensional network structure is used as the film-forming substance of the coating, endowing the coating with excellent weather resistance, scratch resistance, water resistance, and hardness, and significantly improving the wear-resistant and scratch-proof protection effect of the coating. At the same time, the nanoparticles are specifically modified according to the type of matrix resin, enabling the nanoparticles to be better dispersed in the coating system and significantly increasing the interfacial compatibility between the nanoparticles and the resin matrix, thereby significantly reducing the reflection and scattering effects of the coating on visible light and significantly increasing the transmittance of visible light (not less than 82%). The coating has excellent heat-insulating performance, good weather resistance, high coating hardness, high visible light transmittance, and low raw material cost, making it suitable for large-scale promotion and use in building transparent maintenance structures.

[0010] Among them, preferably, the polysiloxane resin is an organic-inorganic hybrid aqueous silicone resin formed by hydrolysis and condensation of silane monomers and acidic silica sol; the polysiloxane resin has a three-dimensional network structure, enabling the cured coating to have excellent weather resistance, scratch resistance, water resistance, and hardness, and providing good wear-resistant and scratch-proof protection for building transparent maintenance structures. More preferably, the specific method for synthesizing the polysiloxane resin includes: adding a catalyst to the silane monomer, then adding acidic silica sol, and mixing and reacting at a temperature of 25 ± 2°C for 1.5 - 2.5 h.

[0011] Preferably, the silane monomer is at least one of methyl orthosilicate, ethyl orthosilicate, methyltrimethoxysilane, phenyltrimethoxysilane, dimethyldimethoxysilane, and 3-glycidoxypropyltrimethoxysilane; the preferred type of silane monomer results in better performance of the polysiloxane resin and higher transmittance of visible light for the formed coating.

[0012] Preferably, the acidic silica sol is a special colloidal solution mainly formed by uniformly dispersing silicon dioxide (SiO 2 ) microparticles in water, and its pH value is 2 - 4.

[0013] Preferably, in the synthesis method of the polysiloxane resin, the mass ratio of the silane monomer to the acidic silica sol is 5 - 10:2 - 5; the preferred mass ratio results in better performance of the synthesized polysiloxane resin and higher transmittance of visible light for the formed coating.

[0014] Preferably, the catalyst is acetic acid, formic acid, or hydrochloric acid.

[0015] Preferably, the addition amount of the catalyst is 0.2-1% of the mass of the silane monomer.

[0016] Among them, the acrylic hydroxyl emulsion is an aqueous emulsion; preferably, the acrylic hydroxyl emulsion is a polymerized hydroxyl acrylic emulsion with a solid content of 30%.

[0017] Among them, preferably, the organic solvent is an ethanol solution of propylene glycol monomethyl ether or an ethanol solution of ethylene glycol monobutyl ether; the preferred organic solvent can make each raw material in the coating disperse more evenly, and the transmittance of the obtained coating to visible light is higher.

[0018] Preferably, in the organic solvent, the mass percentage of ethanol is 40-60%.

[0019] Among them, the basic hindered amine is a nitroxide radical type hindered amine (NOR type); more preferably, the basic hindered amine is one or more of 2,2,6,6-tetramethylpiperidine and its substituted derivatives.

[0020] Among them, through the modification treatment of the nanoparticles with a coupling agent, the steric hindrance between the nanoparticles can be increased, the aqueous dispersibility of the nanoparticles can be improved, agglomeration can be prevented, the nanoparticles are more evenly dispersed in the coating, and the transmittance of the coating to visible light is significantly increased; preferably, when performing the modification treatment, the addition amount of the silane coupling agent is 0.3-0.8% of the nanoparticles.

[0021] Preferably, the silane coupling agent is a mixture of γ-methacryloxypropyltrimethoxysilane and γ-(2,3-epoxypropoxy)propyltrimethoxysilane with a mass ratio of 4-10:1-2.

[0022] Preferably, the modification treatment method of the nanoparticles includes: mixing the nanoparticles and the silane coupling agent, and then performing oscillating grinding with zirconia beads for 2-4 h to obtain.

[0023] Among them, the smaller the particle size of the nanoparticles, the better the barrier effect on ultraviolet and infrared light, and the better the transmittance to visible light, but the dispersibility decreases. Therefore, a suitable particle size range of the nanoparticles can enable the coating to have a better barrier effect on ultraviolet and infrared light, a higher transmittance to visible light, and also have good dispersibility, which is beneficial to improving the performance of the coating. Preferably, the particle size of the nanoparticles is 2-20 nm; more preferably, the particle size of the nanoparticles is 5-10 nm.

[0024] Among them, preferably, the preparation method of the aqueous dispersion of the nanoparticles includes: adding the modified nanoparticles into deionized water, then adding an aqueous dispersant and an aqueous wetting agent, and performing ultrasonic dispersion for 2-3 h to obtain.

[0025] Preferably, the aqueous dispersant is a polymer polyacrylate dispersant, such as: AFCONA-4595, AFCONA-4599, TEGO-755W, TEGO-760W, BYK-190, etc.; its dosage is 1-3% of the mass of the nanoparticles.

[0026] Preferably, the aqueous wetting agent is a silicone wetting agent, such as: AFCONA-3580, BYK-331, BYK-346, etc.; the dosage is 0.5-1.5% of the mass of the nanoparticles.

[0027] Furthermore, in order to achieve the above-mentioned invention purpose, the present invention also provides a preparation method of an aqueous wear-resistant ceramic heat-insulating coating, including: mixing the above raw materials evenly according to the formula to obtain the aqueous wear-resistant ceramic heat-insulating coating.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0029] 1. For the aqueous wear-resistant ceramic heat-insulating coating of the present invention, by using antimony- and tungsten-doped tin dioxide nanoparticles in combination with 2-(2-hydroxyphenyl)-benzotriazole and alkaline hindered amine, a synergistic effect is formed, so that the coating can effectively block the transmission of ultraviolet light (the total blocking rate of ultraviolet rays in natural light is not less than 98%) and infrared light (the total blocking rate of infrared rays in natural light is not less than 90%), significantly improving the heat-insulating effect of the coating.

[0030] 2. For the aqueous wear-resistant ceramic heat-insulating coating of the present invention, polysiloxane resin with a three-dimensional network structure is used as the film-forming substance of the coating, thereby endowing the coating with excellent weather resistance, scratch resistance, water resistance and hardness, and significantly improving the wear-resistant and scratch-proof protection effect of the coating.

[0031] 3. For the aqueous wear-resistant ceramic heat-insulating coating of the present invention, the nanoparticles are specifically modified according to the type of the matrix resin, so that the nanoparticles can be better dispersed in the coating system, and the interfacial compatibility between the nanoparticles and the resin matrix is significantly increased, thereby significantly reducing the reflection and scattering effects of the coating on visible light and significantly increasing the transmittance of the coating to visible light (not less than 82%).

[0032] 4. The aqueous wear-resistant ceramic heat-insulating coating of the present invention has excellent heat-insulating effect, good weather resistance, high coating hardness, high visible light transmittance, and low raw material cost, and is suitable for large-scale popularization and use in building transparent maintenance structures. Specific embodiments

[0033] In order to more clearly describe the invention purpose, technical solution and technical effect advantages in the specific embodiments of the present invention, the following will make a detailed description in combination with the solutions in the specific embodiments of the present invention. The specific technical solutions involved in the following specific embodiments are only for clearly and completely describing the innovative technical solutions of the present invention. They are only a part of the specific implementation solutions that the present invention can adopt, not all embodiments, and should not be understood as a limitation to the innovative solutions of the present invention. Any solutions adopting the same inventive concept of the present invention should be included in the protection scope of the present invention.

[0034] For those skilled in the art, when understanding the solutions described in the specific embodiments of the present invention, they can refer to the conventional technical manuals in the art. At the same time, for the places where the above terms appear, they can make appropriate understanding or adjustment referentially. Without creative labor, the same or similar technical solution implementation situations can be deduced.

[0035] Example 1

[0036] An aqueous wear-resistant ceramic heat-insulating coating is prepared by mixing the following raw material components in parts by weight: 35 parts of nano-particle aqueous dispersion, 60 parts of polysiloxane resin, 30 parts of acrylic hydroxy emulsion, 15 parts of organic solvent, 0.8 part of 2-(2-hydroxyphenyl)-benzotriazole, and 0.8 part of alkaline hindered amine (2,2,6,6-tetramethylpiperidine).

[0037] Among them, the preparation method of the nano-particle aqueous dispersion includes: adding 30 parts of modified nano-particles to 69.8 parts of deionized water, then adding 0.6 part of aqueous dispersant (AFCONA-4595) and 0.3 part of aqueous wetting agent (AFCONA-3580), and ultrasonic dispersing for 2.5 h to obtain;

[0038] The modified nano-particles are obtained by modifying nano-particles with a silane coupling agent (a mixture of γ-methacryloxypropyltrimethoxysilane and γ-(2,3-epoxypropoxy)propyltrimethoxysilane with a mass ratio of 6:1). The specific method includes: mixing 700 parts of nano-particles and 4.5 parts of silane coupling agent, and then performing oscillating grinding with zirconia beads for 3 h to obtain;

[0039] The nano-particles are a mixture of nano-antimony-doped tin dioxide (particle size 8 nm) and nano-tungsten-doped tin dioxide (particle size 6 nm) with a mass ratio of 3:11;

[0040] The specific method for synthesizing the polysiloxane resin includes: adding 0.55 part of catalyst (acetic acid) to 85 parts of silane monomer (tetramethoxysilane), then adding 35 parts of acidic silica sol (pH value 3), and mixing and reacting at a temperature of 25 °C for 2 h to obtain;

[0041] The organic solvent is an ethanol solution of propylene glycol methyl ether, and the mass fraction of ethanol is 50%;

[0042] The acrylic acid hydroxyl emulsion is a polymerized hydroxyl acrylic emulsion with a solid content of 30%.

[0043] Example 2

[0044] A waterborne wear-resistant ceramic heat-insulating coating is prepared by mixing the following raw material components in parts by weight: 20 parts of aqueous nanoparticle dispersion, 50 parts of polysiloxane resin, 20 parts of acrylic acid hydroxyl emulsion, 10 parts of organic solvent, 1 part of 2-(2-hydroxyphenyl)-benzotriazole, and 1 part of basic hindered amine (2,2,6,6-tetramethylpiperidine).

[0045] Among them, the preparation method of the aqueous nanoparticle dispersion includes: adding 35 parts of modified nanoparticles to 64.3 parts of deionized water, then adding 1.05 parts of aqueous dispersant (BYK-190) and 0.525 parts of aqueous wetting agent (BYK-331), and obtaining it by ultrasonic dispersion for 3 h;

[0046] The modified nanoparticles are obtained by modifying the nanoparticles with a silane coupling agent (a mixture of γ-methacryloxypropyltrimethoxysilane and γ-(2,3-epoxypropoxy)propyltrimethoxysilane with a mass ratio of 4:1). The specific method includes: mixing 800 parts of nanoparticles and 6 parts of silane coupling agent, and obtaining it by oscillating and grinding with zirconia beads for 4 h;

[0047] The nanoparticles are a mixture of antimony-doped tin dioxide nanoparticles (particle size 10 nm) and tungsten-doped tin dioxide nanoparticles (particle size 10 nm) with a mass ratio of 1:5;

[0048] The specific method for synthesizing the polysiloxane resin includes: adding 1 part of catalyst (acetic acid) to 100 parts of silane monomer (methyltrimethoxysilane), then adding 50 parts of acidic silica sol (pH value of 2), and carrying out a mixing reaction at a temperature of 27 °C for 1.5 h to obtain;

[0049] The organic solvent is an ethanol solution of ethylene glycol monobutyl ether, and the mass fraction of ethanol is 60%;

[0050] The acrylic acid hydroxyl emulsion is a polymerized hydroxyl acrylic emulsion with a solid content of 30%.

[0051] Example 3

[0052] An aqueous wear-resistant ceramic heat-insulating coating is prepared by mixing the following raw material components in parts by weight: 50 parts of nano-particle aqueous dispersion, 70 parts of polysiloxane resin, 40 parts of acrylic hydroxy emulsion, 20 parts of organic solvent, 0.5 part of 2-(2-hydroxyphenyl)-benzotriazole, and 0.5 part of alkaline hindered amine (4-acetamido-2,2,6,6-tetramethylpiperidine).

[0053] Among them, the preparation method of the nano-particle aqueous dispersion includes: adding 20 parts of modified nano-particles to 79.5 parts of deionized water, then adding 0.2 part of aqueous dispersant (TEGO-755W) and 0.1 part of aqueous wetting agent (BYK-346), and performing ultrasonic dispersion for 2.0 h to obtain;

[0054] The modified nano-particles are obtained by modifying nano-particles with a silane coupling agent (a mixture of γ-methacryloxypropyltrimethoxysilane and γ-(2,3-epoxypropoxy)propyltrimethoxysilane with a mass ratio of 10:1). The specific method includes: mixing 600 parts of nano-particles and 2.5 parts of silane coupling agent, and performing oscillating grinding with zirconia beads for 2 h to obtain;

[0055] The nano-particles are a mixture of nano-antimony-doped tin dioxide (particle size 5 nm) and nano-tungsten-doped tin dioxide (particle size 6 nm) with a mass ratio of 1:3;

[0056] The specific method for synthesizing the polysiloxane resin includes: adding 0.1 part of catalyst (acetic acid) to 50 parts of silane monomers (methyltrimethoxysilane and dimethyldimethoxysilane in a ratio of 1:1), then adding 20 parts of acidic silica sol (pH value 4), and performing a mixing reaction at a temperature of 23 °C for 1.5 h to obtain;

[0057] The organic solvent is an ethanol solution of propylene glycol methyl ether, and the mass fraction of ethanol is 40%;

[0058] The acrylic hydroxy emulsion is a polymerized hydroxy acrylic emulsion with a solid content of 30%.

[0059] Example 4

[0060] An aqueous wear-resistant ceramic heat-insulating coating is prepared by mixing the following raw material components in parts by weight: 35 parts of nano-particle aqueous dispersion, 60 parts of polysiloxane resin, 30 parts of acrylic hydroxy emulsion, 15 parts of organic solvent, 0.8 part of 2-(2-hydroxyphenyl)-benzotriazole, and 0.8 part of alkaline hindered amine (2,2,6,6-tetramethylpiperidine).

[0061] Among them, the preparation method of the aqueous dispersion of nanoparticles includes: adding 30 parts of modified nanoparticles into 69.8 parts of deionized water, then adding 0.6 part of aqueous dispersant (AFCONA-4599) and 0.3 part of aqueous wetting agent (AFCONA-3580), and performing ultrasonic dispersion for 2.5 h to obtain;

[0062] The modified nanoparticles are obtained by modifying the nanoparticles with a silane coupling agent (a mixture of γ-methacryloxypropyltrimethoxysilane and γ-(2,3-epoxypropoxy)propyltrimethoxysilane with a mass ratio of 6:1). The specific method includes: mixing 700 parts of nanoparticles and 2.0 parts of silane coupling agent, and performing oscillating grinding with zirconia beads for 2 h to obtain;

[0063] The nanoparticles are a mixture of antimony-doped tin oxide nanoparticles (particle size 20 nm) and tungsten-doped tin oxide nanoparticles (particle size 20 nm) with a mass ratio of 3:11;

[0064] The specific method for synthesizing the polysiloxane resin includes: adding 0.55 part of catalyst (acetic acid) to 85 parts of silane monomer (tetramethoxysilane), then adding 35 parts of acidic silica sol (pH value 3), and performing mixing reaction at a temperature of 25 °C for 2 h to obtain;

[0065] The organic solvent is an ethanol solution of propylene glycol methyl ether, and the mass fraction of ethanol is 50%;

[0066] The acrylic hydroxy emulsion is a polymerized hydroxy acrylic emulsion with a solid content of 30%.

[0067] Example 5

[0068] An aqueous wear-resistant ceramic heat-insulating coating is prepared by mixing the following raw material components in parts by weight: 35 parts of aqueous dispersion of nanoparticles, 60 parts of polysiloxane resin, 30 parts of acrylic hydroxy emulsion, 15 parts of organic solvent, 0.8 part of 2-(2-hydroxyphenyl)-benzotriazole, and 0.8 part of basic hindered amine (2,2,6,6-tetramethylpiperidine).

[0069] Among them, the preparation method of the aqueous dispersion of nanoparticles includes: adding 30 parts of modified nanoparticles into 69.8 parts of deionized water, then adding 0.6 part of aqueous dispersant (TEGO-760W) and 0.3 part of aqueous wetting agent (BYK-331), and performing ultrasonic dispersion for 2.5 h to obtain;

[0070] The modified nanoparticles are obtained by modifying the nanoparticles with a silane coupling agent (a mixture of γ-methacryloxypropyltrimethoxysilane and γ-(2,3-epoxypropoxy)propyltrimethoxysilane with a mass ratio of 1.5:1). The specific method includes: mixing 700 parts of nanoparticles and 4.5 parts of silane coupling agent, and then performing oscillatory grinding with zirconia beads for 3 h to obtain them;

[0071] The nanoparticles are a mixture of antimony-doped tin dioxide nanoparticles (particle size 8 nm) and tungsten-doped tin dioxide nanoparticles (particle size 6 nm) with a mass ratio of 3:11;

[0072] The specific method for synthesizing the polysiloxane resin includes: adding 0.55 parts of a catalyst (acetic acid) to 85 parts of a silane monomer (tetramethoxysilane), and then adding 55 parts of acidic silica sol (pH value 3), and carrying out a mixing reaction at a temperature of 25 °C for 4 h to obtain it;

[0073] The organic solvent is an ethanol solution of propylene glycol methyl ether with an ethanol mass fraction of 30%;

[0074] The acrylic hydroxyl emulsion is a polymerized hydroxyl acrylic emulsion with a solid content of 30%.

[0075] Example 6

[0076] An aqueous wear-resistant ceramic heat-insulating coating is prepared by mixing the following raw material components in parts by weight: 35 parts of an aqueous dispersion of nanoparticles, 60 parts of polysiloxane resin, 30 parts of acrylic hydroxyl emulsion, 15 parts of organic solvent, 0.8 part of 2-(2-hydroxyphenyl)-benzotriazole, and 0.8 part of an alkaline hindered amine (2,2,6,6-tetramethylpiperidine).

[0077] Among them, the preparation method of the aqueous dispersion of nanoparticles includes: adding 30 parts of modified nanoparticles to 69.8 parts of deionized water, then adding 0.6 part of an aqueous dispersant (BYK-190), and carrying out ultrasonic dispersion for 5 h to obtain it;

[0078] The modified nanoparticles are obtained by modifying the nanoparticles with a silane coupling agent (a mixture of γ-methacryloxypropyltrimethoxysilane and γ-(2,3-epoxypropoxy)propyltrimethoxysilane with a mass ratio of 6:1). The specific method includes: mixing 700 parts of nanoparticles and 4.5 parts of silane coupling agent, and then performing oscillatory grinding with zirconia beads for 3 h to obtain them;

[0079] The nanoparticles are a mixture of antimony-doped tin dioxide nanoparticles (particle size 2 nm) and tungsten-doped tin dioxide nanoparticles (particle size 2 nm) with a mass ratio of 3:11;

[0080] The specific method for synthesizing polysiloxane resin includes: adding 0.55 parts of catalyst (acetic acid) to 85 parts of silane monomer (methyl orthosilicate), then adding 35 parts of acidic silica sol (pH value is 3), and carrying out a mixing reaction at 25 °C for 2 h to obtain;

[0081] The organic solvent is a methanol solution of propylene glycol methyl ether, and the mass fraction of ethanol is 50%;

[0082] The acrylic hydroxyl emulsion is a polymerized hydroxyl acrylic emulsion with a solid content of 30%.

[0083] Comparative Example 1

[0084] A kind of coating, compared with Example 1, the difference is only that: no basic hindered amine is added.

[0085] Comparative Example 2

[0086] A kind of coating, compared with Example 1, the difference is only that: 2-(2-hydroxyphenyl)-benzotriazole is not added.

[0087] Comparative Example 3

[0088] A kind of coating, compared with Example 1, the difference is only that: the polysiloxane resin is replaced with aqueous polyurethane.

[0089] Comparative Example 4

[0090] A kind of coating, compared with Example 1, the difference is only that: in the nanoparticles, the mass ratio of nano-antimony-doped tin dioxide to nano-tungsten-doped tin dioxide is 1:2.

[0091] Comparative Example 5

[0092] A kind of coating, compared with Example 1, the difference is only that: in the aqueous dispersion of nanoparticles, the mass fraction of the modified nanoparticles is 40%.

[0093] Comparative Example 6

[0094] A kind of coating, compared with Example 1, the difference is only that: the nanoparticles are not treated with coupling agent modification.

[0095] Comparative Example 7

[0096] A kind of coating, compared with Example 1, the difference is only that: the weight portion of the aqueous dispersion of nanoparticles is 55 parts.

[0097] Comparative Example 8

[0098] A kind of coating, compared with Example 1, the difference is only that: the weight portion of the polysiloxane resin is 75 parts.

[0099] Comparative Example 9

[0100] A coating is prepared according to the formula and method in Example 1 of Patent Publication No. CN115141506A.

[0101] Comparative Example 10

[0102] A coating is prepared according to the formula and method in Example 1 of Patent Publication No. CN108504275B.

[0103] Experimental Example

[0104] The coatings in Examples 1 - 6 and Comparative Examples 1 - 10 were respectively coated on glass slides to form a 20 - μm - thick coating with uniform thickness, and the transmittance of the coating to ultraviolet light (100 - 400 nm), infrared light (750 - 3000 nm), and visible light (GB / T 2680 - 2021) was measured respectively, as well as the weather resistance of the coating (exposed to a QUV ultraviolet accelerated aging chamber (240H, 0.68 w / m 2 ), and the discoloration time of the coating was observed) and the abrasion resistance (tested by the pencil hardness method). The test results are shown in the following table:

[0105]

[0106] Analysis of the performance test data shows that: for the water - borne wear - resistant ceramic heat - insulating coating provided by the present invention, the surfaces of nano - tungsten - doped tin dioxide (GTO) and nano - antimony - doped tin dioxide (ATO) particles are modified by silane treatment. While improving the hydrophilicity of the nano - particles, the silane side chains grafted on the surfaces of the nano - particles increase the steric hindrance between the particles, significantly improving the dispersibility of the nano - particles, preventing agglomeration, and being more uniformly dispersed in the coating. It can significantly improve the transmittance in the visible light band (the transmittance of visible light in natural light is greater than 82%), and the blocking effect on the infrared and ultraviolet bands; through the synergistic cooperation of 2 - (2 - hydroxyphenyl) - benzotriazole and basic hindered amines with the nano - particles, the blocking rate of the coating to each band of ultraviolet and infrared light can be significantly improved; the total blocking rate of infrared light in natural light is greater than 90%; the total blocking rate of ultraviolet light in natural light is greater than 98%.

[0107] Meanwhile, in the present invention, an organic - inorganic hybrid water - borne silicone resin synthesized by hydrolysis - polycondensation of silane monomers and silica sol is used as the film - forming material, and its three - dimensional network structure can significantly improve the weather resistance and hardness of the coating.

[0108] The above embodiments only describe the basic principles, main features and / or advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The above embodiments and the description in the summary of the invention part only describe the principles or specific cases of the present invention. Without departing from the essence of the innovative idea of the present invention, there are various changes and improvements to the innovative solutions of the present invention, and these changes and improvements all fall within the scope of protection required by the present invention.

Claims

1. A water-based wear-resistant ceramic thermal insulation coating, characterized in that: The invention comprises the following raw material components in parts by weight: 20-50 parts of nanoparticle aqueous dispersion, 50-70 parts of polysiloxane resin, 20-40 parts of acrylic hydroxyl emulsion, 10-20 parts of organic solvent, 0.5-1 parts of 2-(2-hydroxyphenyl)-benzotriazole, and 0.5-1 parts of basic hindered amine; The aqueous dispersion of nanoparticles contains 20-35% by mass of modified nanoparticles, wherein the modified nanoparticles are obtained by modifying the nanoparticles with a silane coupling agent; the nanoparticles are a mixture of nano antimony-doped tin dioxide and nano tungsten-doped tin dioxide in a mass ratio of 1-2:5-6; the alkaline hindered amine is a nitroxide free radical hindered amine; The polysiloxane resin is an organic-inorganic hybrid water-based silicone resin formed by hydrolysis and condensation of a silane monomer and an acidic silica sol; the silane monomer is at least one of methyl orthosilicate, ethyl orthosilicate, methyl trimethoxysilane, phenyl trimethoxysilane, dimethyl dimethoxysilane and 3-glycidyloxypropyl trimethoxysilane; the pH value of the acidic silica sol is 2-4; the mass ratio of the silane monomer to the acidic silica sol is 5-10:2-5; The silane coupling agent is a mixture of γ-methacryloxypropyltrimethoxysilane and γ-(2,3-epoxypropyloxy)propyltrimethoxysilane in a mass ratio of 4-10:1-2.

2. The water-based wear-resistant ceramic thermal insulation coating according to claim 1, characterized in that: The acrylic hydroxyl emulsion is a polymerized hydroxyl acrylic emulsion with a solid content of 30%.

3. The water-based wear-resistant ceramic thermal insulation coating according to claim 1, characterized in that: The organic solvent is an ethanol solution of propylene glycol methyl ether or an ethanol solution of ethylene glycol butyl ether.

4. The water-based wear-resistant ceramic thermal insulation coating according to any one of claims 1 to 3, characterized in that: The particle size of the nanoparticles is 2-20 nm.

5. The water-based wear-resistant ceramic thermal insulation coating according to any one of claims 1 to 3, characterized in that: The preparation method of the nanoparticle aqueous dispersion comprises: adding the modified nanoparticles into deionized water, then adding an aqueous dispersant and an aqueous wetting agent, and dispersing the aqueous dispersion by ultrasonic for 2-3 hours to obtain the nanoparticles.

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