Anti-condensation coating containing aerogel and preparation process of anti-condensation coating

Abstract

The invention relates to an aerogel-containing anti-condensation coating and a preparation process thereof, and belongs to the technical field of building coatings. Comprising the following components in parts by mass: 25-50 parts of aerogel, 10-25 parts of compound filler, 30-50 parts of polymer emulsion, 10-15 parts of infrared reflection filler, 5-15 parts of a coalescing agent, 0.5-1 part of a dispersing agent, 0.5-2 parts of a defoaming agent, 1-3 parts of a flatting agent and 15-30 parts of deionized water, the prepared coating is low in heat conductivity coefficient and excellent in anti-condensation performance, and the effect can be achieved when the thickness reaches 3 mm during construction.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of architectural coatings, and relates to a dew-proof coating containing aerogel and a preparation process thereof. BACKGROUND

[0002] Dew formation is a natural process in which water vapor condenses into liquid water when air with high humidity contacts the surface of an object with a temperature lower than its dew point. In the field of architecture, dew formation is commonly found on the inner surface of exterior walls, basements, warehouses, pipelines, and indoor walls in southern China during the "back to the south" and plum rain seasons. This dew formation not only affects the aesthetics, but also affects the safety and service life of buildings and equipment.

[0003] Current methods to prevent dew formation include equipment or house structure design, adding insulation layers, and using dew-proof coatings. The structure design is costly and complex to construct, the addition of insulation layers is complex to construct, costly, and occupies indoor space, and dew-proof coatings are widely used due to their simple construction, low cost, and no impact on the building structure.

[0004] In existing dew-proof coatings, on the one hand, coatings with air permeability and water absorption tend to be saturated with water, have a short dew-proof effect, and the water absorption of the coating can reduce adhesion; on the other hand, dew-proof coatings based on thermal insulation materials require thick coating (7 mm and above) to achieve dew-proof effect, which is costly. Aerogel, as a new type of nano-porous material, has extremely high specific surface area, extremely low thermal conductivity, and excellent porosity, and has great potential in the field of thermal insulation. Theoretically, the application of aerogel in coatings can achieve extremely high thermal insulation efficiency with extremely low addition amount, thereby avoiding performance degradation due to excessive fillers. However, the inherent high hydrophilicity, low strength, and difficulty in dispersion and stability in liquid systems of aerogel materials pose great challenges to its direct introduction into the coating system.

[0005] Therefore, it is an urgent problem to be solved to realize a dew-proof coating containing aerogel with strong adhesion, thin coating, and long-term effect. SUMMARY

[0006] The present application aims to provide a dew-proof coating containing aerogel and a preparation process thereof. The coating prepared by the present application has a low thermal conductivity (≤0.030 W / (m﹒K)) and excellent dew-proof properties.

[0007] The object of the present application can be achieved by the following technical solutions: In one aspect, the present application provides an anti-condensation coating containing aerogel, comprising the following components in mass fraction: 25-50 parts of aerogel, 10-25 parts of compound filler, 30-50 parts of polymer emulsion, 10-15 parts of infrared reflective filler, 5-15 parts of film-forming aid, 0.5-1 part of dispersing agent, 0.5-2 parts of defoaming agent, 1-3 parts of leveling agent and 15-30 parts of deionized water. The compound filler is a mixture of vitrified microbeads and mica powder in a mass ratio of 1:1; and the infrared reflective filler is antimony-doped rutile TiO2 which is surface-treated with poly-N-isopropyl acrylamide.

[0008] Further, the aerogel is pretreated when used, and the specific process is as follows: The aerogel is dispersed in an aqueous acrylic emulsion with a mass concentration of 25-35%, and the mass ratio of the aqueous acrylic solution to the aerogel is (1-2):1; the mixture is stirred at a speed of 300 r / min for 35-50 min, and then dried to obtain the aerogel for standby use.

[0009] Further, the average particle size of the aerogel is 100 μm, and the aerogel is one or more of silica aerogel particles, titanium dioxide aerogel particles, zirconium dioxide aerogel particles and aluminum trioxide aerogel particles.

[0010] Further, the polymer emulsion is a mixture of silicone-modified acrylic emulsion and silica sol in a mass ratio of 10:1.

[0011] Further, the infrared reflective filler is prepared as follows: A titanium tetrachloride solution with a mass fraction of 45% is prepared, and antimony trichloride is added thereto and mixed uniformly, wherein the molar ratio of Ti to Sb is 90:5; the titanium tetrachloride solution and a 100℃ aqueous solution in a volume ratio of 1:1 are pyrolyzed for 2 h, and then aged for 6 h; after filtration and drying, the mixture is calcined at 300℃ for 2 h, and then calcined at 500℃ for 2 h; after cooling and crushing, antimony-doped rutile TiO2 nano-powder is obtained. Then, the antimony-doped rutile TiO2 nano-powder is dispersed in a 40wt% ethanol aqueous solution to form a stable suspension, and then poly-N-isopropyl acrylamide is added to the suspension to form a mixture; the mixture is stirred at room temperature for 2-3 h, and then filtered, washed and dried to obtain the infrared reflective filler, wherein the mass ratio of the antimony-doped rutile TiO2 nano-powder to the poly-N-isopropyl acrylamide is 1:(0.5-0.6).

[0012] Further, the defoaming agent is one or more of mineral oil, silicone and polyether.

[0013] Further, the film forming aid is one or more of dodecanol ester, propylene glycol butyl ether, propylene glycol phenyl ether, ethylene glycol butyl ether acetate, propylene glycol methyl ether acetate.

[0014] Further, the dispersant is one or more of polycarboxylate dispersant, polyacrylic acid, sodium polyacrylate, polyvinyl alcohol, polyethylene glycol.

[0015] Further, the leveling agent is a silicone type leveling agent or an acrylate type leveling agent.

[0016] In another aspect, the present application provides a preparation process of the anti-condensation coating containing aerogel as described above, comprising the following steps: S1, according to mass fraction, mix deionized water, dispersant and 50% defoamer, stir at a speed of 300-500 rpm for 35-50 min, add the prepared aerogel, fully stir to make the aerogel completely wet with liquid to obtain mixture A; S2, mix the polymer emulsion and the compounded filler, disperse at a speed of 2000-3000 rpm for 25-45 min, then add the film forming aid and the leveling agent, continue to disperse at the same speed for 25-40 min to obtain mixture B; S3, add mixture A to mixture B, disperse at a speed of 800-1000 rpm for 20-40 min, then add the remaining 50% defoamer and the infrared reflective filler, stir for 25-35 min to obtain the anti-condensation coating containing aerogel.

[0017] Advantages of the present application: The present application provides an anti-condensation coating containing aerogel, which uses silicone modified acrylic emulsion as the main polymer base, and forms a triple barrier system through aerogel and compounded filler, takes aerogel as the core functional body, takes lightweight porous filler, i.e. vitrified microsphere, as the auxiliary heat insulation body, and takes flaky filler, i.e. mica powder, as the water vapor barrier and reinforcing body, which produces a synergistic effect with the heat insulation performance of aerogel, and comprehensively improves the anti-condensation effect of the coating; meanwhile, by adding the infrared reflective filler treated by poly N-isopropyl acrylamide to the coating, near-infrared radiation is reflected, the heat input of external heat source to the coating is reduced, and in combination with aerogel, the two heat transfer modes of conduction and radiation are synergistically controlled, and the heat preservation effect of the coating is improved. In the process of preparing the coating, the aerogel is first wetted and then dispersed, which avoids the hard agglomeration of aerogel that cannot be dispersed and the destruction of the structure during the mixing process, so that the prepared coating has excellent heat preservation and anti-condensation properties. DETAILED DESCRIPTION

[0018] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined object, the following embodiments are combined to illustrate the specific embodiments, structures, features and effects of the present application in detail.

[0019] In order to develop an aero gel that can inherit the excellent heat insulation performance and also form a coating with high anti-condensation function, the present application provides an anti-condensation coating containing aero gel, which comprises the following components in mass fraction: 25-50 parts of aero gel, 10-25 parts of a compound filler, 30-50 parts of a polymer emulsion, 10-15 parts of an infrared reflective filler, 5-15 parts of a film forming aid, 0.5-1 part of a dispersing agent, 0.5-2 parts of a defoaming agent, 1-3 parts of a leveling agent and 15-30 parts of deionized water. The compound filler is vitrified microbeads and mica powder in a mass ratio of 1:1; and the infrared reflective filler is antimony-doped rutile TiO2 which is surface treated by poly-N-isopropyl acrylamide.

[0020] The present application selects silicone-modified acrylic emulsion as the main polymer base, which has both the hydrophobicity and weather resistance of silicone and the elasticity and adhesion of acrylic, so it can resist the stress cracking of the substrate caused by temperature difference and prevent condensation penetration caused by cracks. The inorganic / organic composite system of silicone-modified acrylic emulsion and silica sol is selected, the inorganic coating forms a microporous structure after film formation, has excellent moisture permeability, can complement the heat insulation of aero gel and the elasticity of organic emulsion, and improve the performance of the coating. Therefore, the balance between moisture resistance and moisture permeability in the coating can be achieved, and through appropriate moisture permeability, the trace amount of water vapor in the wall body can be discharged, preventing water vapor from condensing at the coating-substrate interface, resulting in loss of adhesion and internal mold.

[0021] The present application forms a triple barrier system by aero gel and compound filler, takes aero gel as the core functional body, takes lightweight porous filler vitrified microbeads as the auxiliary heat insulation body, and takes sheet-shaped filler mica powder as the water vapor barrier and reinforcing body, which has a synergistic effect with the heat insulation performance of aero gel, and the comprehensive anti-condensation effect is much better than that of a single aero gel or single filler.

[0022] The coating prepared by the present application has a three-dimensional network structure skeleton, the low thermal conductivity can reduce the heat transfer of the surface coating to the interior of the wall, and the infrared reflective filler is added, so the coating has high light reflection and heat reflection, which can make up for the performance discount caused by insufficient construction thickness of the surface coating, and ensure the effect of the entire coating.

[0023] In a specific embodiment, the aero gel is pretreated when used, and the specific process is as follows: The aerogel is dispersed in an aqueous acrylic emulsion with a mass concentration of 25-35%, wherein the mass ratio of the aqueous acrylic solution to the aerogel is (1-2):1, and stirring is performed at a rotation speed of 300 r / min for 35-50 min, and after drying, the aerogel is obtained for standby use.

[0024] In a specific embodiment, the average particle size of the aerogel particles is 100 μm, and the aerogel particles are one or more of silica aerogel particles, titania aerogel particles, zirconia aerogel particles, and alumina aerogel particles.

[0025] The original aerogel nanoskeleton is relatively weak, low in strength, and high in brittleness. Surface treatment with the aqueous acrylic emulsion makes the aerogel have better interfacial compatibility with the polymer emulsion, improves the dispersion stability and the film density, and forms a flexible polymer film on the surface and the pore entrance of the aerogel particles after drying, which can improve the compression resistance and shear resistance of the aerogel, can withstand mechanical forces in the subsequent paint production and use process, and protect the nanometer porous structure from being damaged. At the same time, the coating layer on the surface can effectively block the direct contact of water molecules with the inner core of the aerogel, improve the performance stability, and help the aerogel to better interact with the compounded fillers.

[0026] In a specific embodiment, the polymer emulsion is a silicone-modified acrylic emulsion and a silica sol with a mass ratio of 10:1.

[0027] Under this ratio, the organic resin and inorganic material are adjusted to help achieve the best balance point of the thermal conductivity coefficient and the water vapor transmission rate of the coating.

[0028] In a specific embodiment, the preparation process of the infrared reflective filler is as follows: A titanium tetrachloride solution with a mass fraction of 45% is prepared, and antimony trichloride is added and uniformly mixed, wherein the molar ratio of Ti to Sb is 90:5. The titanium tetrachloride solution with a volume ratio of 1:1 is pyrolyzed with the 100℃ aqueous solution for 2 h, and then aged for 6 h. After filtration and drying, the temperature is first increased to 300℃ for calcination for 2 h, and then increased to 500℃ for calcination for 2 h. After cooling and crushing, antimony-doped rutile TiO2 nano-powder is obtained. Subsequently, the antimony-doped rutile TiO2 nano-powder is dispersed in a 40wt% ethanol aqueous solution to form a stable suspension. Then, poly N-isopropyl acrylamide is added to the suspension to form a mixed solution. The mixed solution is stirred at room temperature for 2-3 h. After filtration, washing, and drying, the infrared reflective filler is obtained, wherein the mass ratio of the antimony-doped rutile TiO2 nano-powder to the poly N-isopropyl acrylamide is 1:(0.5-0.6).

[0029] Rutile titanium dioxide belongs to tetragonal system, has high atomic packing density, small unit cell, and unique lattice structure, which endows it with extremely high refractive index, much higher than common white pigments, high refractive index makes light on the surface of the particle strongly scattered, including infrared light, so it has extremely high reflectivity to near-infrared rays in sunlight, and near-infrared rays are the main source of heat in solar radiation. Sb is doped in it, impurity energy levels (such as the energy level of Sb 5 ⁺ / Sb 3 ⁺) can be introduced in the forbidden band of rutile titanium dioxide, and the forbidden band width is reduced, so that the material can absorb lower energy infrared light, thereby enhancing the absorption of infrared light and improving the infrared reflectivity.

[0030] And in order to improve the dispersibility of the infrared reflective filler and avoid agglomeration, surface treatment with poly N-isopropyl acrylamide can improve the dispersibility of the Sb-doped rutile TiO2 nano powder in the medium, reduce the agglomeration phenomenon, help form a more effective light reflection network, and further improve the performance of the coating. At the same time, poly N-isopropyl acrylamide has temperature sensitivity and presents hydrophobicity at high temperature, which is beneficial to the rapid sliding of the small condensation water droplets formed, so as to keep the surface dry and improve the anti-condensation property of the coating.

[0031] In the present application, aerogel mainly keeps warm by inhibiting heat conduction to prevent the surface temperature from being too low. Therefore, infrared reflective fillers are added therein to reduce the heat input of external heat sources (such as sunlight and indoor heat sources) to the coating from the source by reflecting near-infrared radiation. The combination of the two achieves synergistic control of the two heat transfer modes of conduction and radiation, thereby improving the heat preservation effect of the coating.

[0032] In a specific embodiment, the defoaming agent is one or more of mineral oil, silicone, and polyether.

[0033] In a specific embodiment, the film-forming aid is one or more of dodecanol ester, propylene glycol butyl ether, propylene glycol phenyl ether, ethylene glycol butyl ether acetate, and propylene glycol methyl ether acetate.

[0034] In a specific embodiment, the dispersant is one or more of polycarboxylate dispersant, polyacrylic acid, sodium polyacrylate, polyvinyl alcohol, and polyethylene glycol.

[0035] In a specific embodiment, the leveling agent is a silicone leveling agent or an acrylate leveling agent.

[0036] The film-forming aid added in the present application can help the emulsion polymer particles to fuse and form a continuous, dense and smooth paint film after application. The defoaming agent added can inhibit the generation of foam during the preparation and application of the coating and eliminate the generated foam. The high molecular dispersant selected in the present application can prevent the aggregation of the components in the coating, so that the aerogel and filler particles are stably suspended in the coating system, preventing their settlement and caking, and helping to exert the performance of the coating. The leveling agent can improve the rheological properties of the coating, so that it can flow and spread better after application, forming a smooth and flat surface.

[0037] In another aspect, the present application provides a preparation process of the anti-condensation coating containing aerogel as described above, comprising the following steps: S1, according to the mass fraction, mix deionized water, dispersant and 50% defoaming agent, stir at a speed of 300-500 rpm for 35-50 min, add the prepared aerogel, fully stir to make the aerogel completely wetted by the liquid to obtain mixture A; S2, mix the polymer emulsion and the compounded filler, disperse at a speed of 2000-3000 rpm for 25-45 min, then add the film-forming aid and the leveling agent, continue to disperse at the same speed for 25-40 min to obtain mixture B; S3, add mixture A to mixture B, disperse at a speed of 800-1000 rpm for 20-40 min, then add the remaining 50% defoaming agent and the infrared reflective filler, stir for 25-35 min to obtain the anti-condensation coating containing aerogel.

[0038] In the preparation process of the present application, the aerogel is first wetted and then dispersed, which can avoid the direct addition of the aerogel into the high-viscosity system and the generation of hard agglomerates that cannot be dispersed. In the specific process, long-time stirring at low speed ensures that the dispersant and the defoaming agent are completely dissolved and uniformly distributed in the water, so that they reach the best active state and prepare for the subsequent efficient dispersion of the powder. The addition of half of the defoaming agent in advance can effectively inhibit the generation of a large amount of bubbles when the powder is added subsequently due to the air entrained by the powder, creating a low-foaming environment for the system, which is conducive to the wetting of the powder. Low-speed stirring can also prevent the fragile porous nanoskeleton of the aerogel from being damaged under high-speed shearing, protecting its core heat insulation performance. Mixing the polymer emulsion and the compounded filler can ensure the uniformity of the emulsion and avoid the damage to the stability of the emulsion by high shear force. After all the high-speed and medium-speed stirring, the system may introduce new bubbles, so the addition of the remaining defoaming agent and the infrared reflective filler can effectively eliminate these bubbles generated in the process, preventing defects such as pinholes and fish eyes during brushing, so as to obtain a coating with excellent anti-condensation and thermal insulation properties.

[0039] Hereinafter, the application provided by the present application will be further described in detail through specific examples.

[0040] It should be noted that in the following examples, unless otherwise specified, the raw materials used can be obtained by commercial purchase or prepared by conventional methods, and the experimental methods not specified with specific conditions are conventional methods and conventional conditions known in the art.

[0041] In the following examples and comparative examples, the silicone-modified acrylic emulsion is UC-3300, which is purchased from Guangzhou Haoyi New Material Technology Co., Ltd., the silica sol is ZS-25, which is purchased from Zhejiang Yuda Chemical Co., Ltd.; the defoaming agent used is silicone defoaming agent HY-709, which is purchased from Hubei Shiteng Chemical Technology Co., Ltd., with the order number 0213; the leveling agent selected is an acrylate leveling agent with the model number BYK-385.

[0042] Example 1 It comprises the following components in mass fraction: 25 parts of aerogel, 10 parts of compounded filler, 30 parts of polymer emulsion, 10 parts of infrared reflective filler, 5 parts of dodecanol ester, 0.5 parts of polyethylene glycol, 0.5 parts of defoaming agent, 1 part of leveling agent and 15 parts of deionized water.

[0043] The compounded filler is a mixture of vitrified microbeads and mica powder in a mass ratio of 1:1; the polymer emulsion is a mixture of silicone-modified acrylic emulsion and silica sol in a mass ratio of 10:1.

[0044] The preparation process of the infrared reflective filler is as follows: A titanium tetrachloride solution with a mass fraction of 45% is prepared, and antimony trichloride is added and uniformly mixed, wherein the molar ratio of Ti to Sb is 90:5. The titanium tetrachloride solution with a volume ratio of 1:1 is pyrolyzed in the 100℃ aqueous solution for 2h, and then aged for 6h. After filtration and drying, the mixture is first calcined at 300℃ for 2h, and then calcined at 500℃ for 2h. After cooling and crushing, antimony-doped rutile TiO2 nano-powder is obtained. Subsequently, the antimony-doped rutile TiO2 nano-powder is dispersed in a 40wt% ethanol aqueous solution to form a stable suspension. Then, poly N-isopropyl acrylamide is added to the suspension to form a mixture. The mixture is stirred at room temperature for 2h. After filtration, washing and drying, the infrared reflective filler is obtained, wherein the mass ratio of the antimony-doped rutile TiO2 nano-powder to the poly N-isopropyl acrylamide is 1:0.5.

[0045] Preparation of anti-dew coating containing aerogel: S1, dispersing the silica aerogel in an aqueous acrylic emulsion with a mass concentration of 25%, wherein the mass ratio of the aqueous acrylic solution to the aerogel is 1:1, stirring at a speed of 300 r / min for 35 min, and obtaining the aerogel for standby after drying; According to the mass fraction, deionized water, dispersant and 50% antifoaming agent are mixed, stirred at a speed of 300 rpm for 35 min, the standby aerogel is added, and the mixture A is obtained by fully stirring to make the aerogel completely wet with liquid. S2, mixing the polymer emulsion and the compounded filler, dispersing for 25 min at a speed of 2000 rpm, then adding the film-forming aid and the leveling agent, maintaining the speed and continuing to disperse for 25 min, to obtain the mixture B; S3, adding the mixture A to the mixture B, dispersing for 20 min at a speed of 800 rpm, then adding the remaining 50% antifoaming agent and the infrared reflective filler, and stirring for 25 min to obtain the anti-fogging coating containing the aerogel.

[0046] Example 2 The components include 35 parts of aerogel, 15 parts of compounded filler, 40 parts of polymer emulsion, 13 parts of infrared reflective filler, 10 parts of lauryl alcohol ester, 0.7 parts of polyethylene glycol, 1 part of antifoaming agent, 2 parts of leveling agent and 22 parts of deionized water.

[0047] The compounded filler is a mass ratio of 1:1 of vitrified microbeads and mica powder; and the polymer emulsion is a mass ratio of 10:1 of silicone-modified acrylic emulsion and silica sol.

[0048] The preparation process of the infrared reflective filler is as follows: A titanium tetrachloride solution with a mass fraction of 45% is prepared, antimony trichloride is added and mixed uniformly, the molar ratio of Ti to Sb is 90:5, the volume ratio of the titanium tetrachloride solution to the 100℃ aqueous solution is 1:1, and pyrolysis is carried out for 2h, followed by aging treatment for 6h, filtration, drying, calcination at 300℃ for 2h, and then calcination at 500℃ for 2h, and the antimony-doped rutile TiO2 nano-powder is obtained after cooling and crushing; Then the antimony-doped rutile TiO2 nano-powder is dispersed in a 40wt% ethanol aqueous solution to form a stable suspension, then poly N-isopropyl acrylamide is added to the suspension to form a mixed solution, stirred at room temperature for 2-3h, and the infrared reflective filler is obtained after filtration, washing and drying, wherein the mass ratio of the antimony-doped rutile TiO2 nano-powder to the poly N-isopropyl acrylamide is 1:0.55.

[0049] Preparation of the anti-fogging coating containing the aerogel: S1, dispersing the silica aerogel in an aqueous acrylic emulsion with a mass concentration of 25-35%, wherein the mass ratio of the aqueous acrylic solution to the aerogel is 1.5:1, stirring at a speed of 300 r / min for 40 min, and obtaining the aerogel for standby after drying; According to the mass fraction, deionized water, dispersant and 50% antifoaming agent are mixed, stirred at a speed of 400 rpm for 40 min, the standby aerogel is added, and the aerogel is fully liquid wetted to obtain a mixture A; S2, mixing the polymer emulsion and the compounded filler, dispersing at a speed of 2500 rpm for 35 min, then adding the film forming aid and the leveling agent, maintaining the speed and continuing to disperse for 30 min to obtain a mixture B; S3, adding the mixture A to the mixture B, dispersing at a speed of 900 rpm for 30 min, then adding the remaining 50% antifoaming agent and the infrared reflective filler, stirring for 30 min to obtain the anti-condensation coating containing the aerogel.

[0050] Example 3 The components include 50 parts of aerogel, 25 parts of compounded filler, 50 parts of polymer emulsion, 15 parts of infrared reflective filler, 15 parts of dodecanol ester, 1 part of polyethylene glycol, 2 parts of antifoaming agent, 3 parts of leveling agent and 30 parts of deionized water.

[0051] The compounded filler is a mass ratio of 1:1 of vitrified microbeads and mica powder; the polymer emulsion is a mass ratio of 10:1 of silicone modified acrylic emulsion and silica sol.

[0052] The preparation process of the infrared reflective filler is as follows: A titanium tetrachloride solution with a mass fraction of 45% is prepared, antimony trichloride is added and mixed uniformly, the molar ratio of Ti to Sb is 90:5, the volume ratio of the titanium tetrachloride solution to the 100℃ aqueous solution is 1:1, and pyrolysis is carried out for 2h, followed by aging treatment for 6h, filtration and drying, then heat treatment at 300℃ for 2h, and then heat treatment at 500℃ for 2h, and the antimony-doped rutile TiO2 nano powder is obtained after cooling and crushing; The antimony-doped rutile TiO2 nano powder is then dispersed in a 40wt% ethanol aqueous solution to form a stable suspension, then poly N-isopropyl acrylamide is added to the suspension to form a mixed solution, stirred at room temperature for 3h, filtered, washed and dried to obtain the infrared reflective filler, wherein the mass ratio of the antimony-doped rutile TiO2 nano powder to the poly N-isopropyl acrylamide is 1:0.6.

[0053] Preparation of the anti-condensation coating containing the aerogel: S1, the silica aerogel is dispersed in an aqueous acrylic emulsion with a mass concentration of 35%, wherein the mass ratio of the aqueous acrylic solution to the aerogel is 2:1, and stirring is performed at a rotation speed of 300 r / min for 50 min, and after drying, a standby aerogel is obtained; According to mass parts, deionized water, dispersant and 50% antifoaming agent are mixed, stirring is performed at a rotation speed of 500 rpm for 50 min, the standby aerogel is added, and the aerogel is completely liquid wetted by fully stirring to obtain a mixture A; S2, the polymer emulsion and the compounded filler are mixed, and dispersion is performed at a rotation speed of 3000 rpm for 45 min, then the film-forming aid and the leveling agent are added, and dispersion is continued at the same rotation speed for 40 min to obtain a mixture B; S3, the mixture A is added to the mixture B, and dispersion is performed at a rotation speed of 1000 rpm for 40 min, then the remaining 50% antifoaming agent and the infrared reflective filler are added, and stirring is performed for 35 min to obtain the anti-condensation coating containing the aerogel.

[0054] Comparative Example 1 Comparative Example 1 is basically the same as Example 1, except that the infrared reflective filler is not treated with poly-N-isopropyl acrylamide in the present comparative example.

[0055] Comparative Example 2 Comparative Example 2 is basically the same as Example 1, except that the infrared reflective filler is not added in the present comparative example.

[0056] Comparative Example 3 Comparative Example 3 is basically the same as Example 1, except that the aerogel is not treated with the aqueous acrylic solution in the present comparative example.

[0057] Comparative Example 4 Comparative Example 4 is basically the same as Example 1, except that the compounded filler is only vitrified microbeads in the present comparative example.

[0058] Comparative Example 5 Comparative Example 5 is basically the same as Example 1, except that the compounded filler is only mica powder in the present comparative example.

[0059] Comparative Example 6 Comparative Example 6 is basically the same as Example 1, except that the compounded filler is not added in the present comparative example.

[0060] Comparative Example 7 Comparative Example 7 is basically the same as Example 1, except that the silica sol is not added in the present comparative example.

[0061] Comparative Example 8 Comparative Example 8 is basically the same as Example 1, except that the aerogel is not added in the present comparative example.

[0062] Performance test: The coating prepared by the examples and the comparative examples was sprayed on the surface of a building base material (cement mortar plate, size of 100cm*100cm*5cm) as a test base, and the coating thickness was 3mm.

[0063] 1. Dew point and dew amount: tested according to the standard HG / T 4560-2013 “Test method for dew prevention performance of coating”, the test time was 120min, the temperature of the temperature and humidity control cabin was 25±0.5℃, the relative humidity was 95±3%, and the temperature of the circulating water bath was 5±0.5℃; 2. Thermal conductivity: tested according to the standard GB / T 10296-2008, and the obtained test results were as shown in Table 1: Table 1 Group Dew point / min Dew amount / g Thermal conductivity W / (m.K) Example 1 84 2.4 0.029 Example 2 87 2.1 0.028 Example 3 85 2.3 0.029 Comparative Example 1 78 3.1 0.041 Comparative Example 2 69 4.2 0.053 Comparative Example 3 77 3.2 0.032 Comparative Example 4 75 3.5 0.039 Comparative Example 5 73 3.8 0.038 Comparative Example 6 62 5.9 0.058 Comparative Example 7 80 2.9 0.035 Comparative Example 8 50 8.1 0.066 As shown in Table 1, the coating prepared by the present application has a long dew point time and a small dew amount, which indicates that it has good dew prevention performance, and according to the standard HG / T 4560-2013, the adhesive strength of examples 1-3 is 0.9MPa, 1.3MPa and 1.1MPa respectively, and the effect can be achieved when the coating thickness is only 3mm; the thermal conductivity of the coating prepared by the present application is low, and the heat preservation effect can be achieved.

[0064] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content to obtain equivalent embodiments with equivalent changes, without departing from the scope of the technical solution of the present application. Any modification, equivalent change and modification of the above embodiments according to the technical essence of the present application, which does not depart from the technical solution of the present application, still belongs to the scope of the technical solution of the present application.

Claims

1. An anti-fogging coating containing aerogel, characterized in that, The composition comprises the following components by mass fraction: 25-50 parts of aerogel, 10-25 parts of compound filler, 30-50 parts of polymer emulsion, 10-15 parts of infrared reflective filler, 5-15 parts of film-forming aid, 0.5-1 part of dispersant, 0.5-2 parts of defoaming agent, 1-3 parts of leveling agent, and 15-30 parts of deionized water; The compound filler is vitrified microsphere and mica powder in a mass ratio of 1:1; and the infrared reflective filler is antimony-doped rutile TiO2 which is surface-treated by poly-N-isopropyl acrylamide.

2. The anti-fogging coating containing aerogel according to claim 1, characterized in that, The aerogel is pretreated before use, and the specific process is as follows: The aerogel is dispersed in an aqueous acrylic emulsion with a mass concentration of 25-35%, and the mass ratio of the aqueous acrylic solution to the aerogel is (1-2):1; stirring is performed at a speed of 300 r / min for 35-50 min, and the aerogel is obtained after drying.

3. The anti-fogging coating containing aerogel according to claim 1, characterized in that, The average particle size of the aerogel particles is 100 μm, and the aerogel particles are one or more of silica aerogel particles, titanium dioxide aerogel particles, zirconium dioxide aerogel particles, and aluminum trioxide aerogel particles.

4. The anti-fogging coating containing aerogel according to claim 1, characterized in that, The polymer emulsion is a silicone-modified acrylic emulsion and a silica sol in a mass ratio of 10:

1.

5. The anti-fogging coating containing aerogel according to claim 1, characterized in that, The preparation process of the infrared reflective filler is as follows: A titanium tetrachloride solution with a mass fraction of 45% is prepared, antimony trichloride is added and uniformly mixed, the molar ratio of Ti to Sb is 90:5, the titanium tetrachloride solution with a volume ratio of 1:1 is pyrolyzed in the 100℃ aqueous solution for 2h, and then aged for 6h, filtered, dried, calcined at 300℃ for 2h, then heated to 500℃ for 2h, cooled, crushed, and then antimony-doped rutile TiO2 nano-powder is obtained; Then the antimony-doped rutile TiO2 nano-powder is dispersed in a 40wt% ethanol aqueous solution to form a stable suspension, then poly-N-isopropyl acrylamide is added to the suspension to form a mixed solution, stirring is performed at room temperature for 2-3h, and then the infrared reflective filler is obtained after filtration, washing and drying, wherein the mass ratio of the antimony-doped rutile TiO2 nano-powder to the poly-N-isopropyl acrylamide is 1:(0.5-0.6).

6. The anti-fogging coating containing aerogel according to claim 1, characterized in that, The defoaming agent is one or more of mineral oil, silicone, and polyether.

7. The anti-fogging coating containing aerogel according to claim 1, characterized in that, The film-forming aid is one or more of dodecanol ester, propylene glycol butyl ether, propylene glycol phenyl ether, ethylene glycol butyl ether acetate, and propylene glycol methyl ether acetate.

8. The anti-fogging coating containing aerogel according to claim 1, characterized in that, The dispersant is one or more of polycarboxylate dispersant, polyacrylic acid, polyacrylic acid sodium, polyvinyl alcohol, and polyethylene glycol.

9. The anti-fogging aerogel-containing coating of claim 1, wherein, The leveling agent is a silicone-type leveling agent or an acrylate-type leveling agent.

10. A process for the preparation of an anti-fogging coating containing aerogel according to any one of claims 1 to 9, characterized in that, The method comprises the following steps: S1, by mass fraction, mix deionized water, dispersant, and 50% defoaming agent, stir at a speed of 300-500 rpm for 35-50 min, add the prepared aerogel, and fully stir to make the aerogel completely wetted by the liquid to obtain a mixture A; S2, mixing the polymer emulsion and the compound filler, dispersing for 25-45 min at a rotation speed of 2000-3000 rpm, adding the film forming aid and the leveling agent, maintaining the rotation speed and continuing to disperse for 25-40 min to obtain a mixture B; S3, adding the mixture A into the mixture B, dispersing for 20-40 min at a rotation speed of 800-1000 rpm, then adding the remaining 50% defoaming agent and the infrared reflective filler, stirring for 25-35 min to obtain the anti-condensation coating containing aerogel.