Aqueous thermal barrier coating and method of making the same

Abstract

The application discloses a kind of water-based thermal insulation coating and preparation method thereof.The water-based thermal insulation coating includes: hollow glass microsphere I, 5-10 parts;Hollow glass microsphere II, 15-20 parts;Titanium dioxide, 10-20 parts;Emulsion, 30-45 parts;Modified carbon nanotube, 0.1-2.5 parts;Auxiliary agent, 1-8 parts;Water, 10-25 parts.The coating provided by the application combines the three action mechanisms of radiation, reflection and barrier, and controls the particle size and addition amount of fillers, so that the coating has good thermal insulation, high adhesion and strong corrosion resistance.

Description

Technical Field

[0001] This invention relates to the field of coating preparation technology, and in particular to a water-based heat-insulating coating for petrochemical storage tanks and its preparation method. Background Technology

[0002] Storage tanks are temperature-sensitive. Under summer sunlight, the outer surface of refined oil storage tanks can reach temperatures of 60-80°C, causing the internal temperature to rise and accelerating oil evaporation. Oil inside the tank diffuses into the surrounding environment from the tank valves, resulting in oil loss, environmental pollution, and threatening the safety of the tank farm. Traditional cooling methods use spraying water to cool the tank's outer wall, but this is wasteful of water and electricity and can accelerate tank wall corrosion. Therefore, it is necessary to develop and apply heat-insulating coatings to reduce the internal temperature of the tank.

[0003] In addition to meeting energy-saving and heat-insulating requirements, environmental protection is a crucial requirement for the development of new materials today and in the future. Solvent-based coatings used in the construction of existing storage tanks contain large amounts of volatile organic compounds (VOCs), which harm human health, pollute the environment, and pose safety hazards. With increasingly stringent environmental requirements, water-based coatings have a promising future.

[0004] Patent CN102127346 A discloses a heat-insulating coating and its preparation method, using ceramic hollow microspheres and aluminum silicate powder, but the coating's corrosion resistance needs improvement. CN103819989A discloses a water-based anti-corrosion and heat-insulating coating and its preparation method, using a single-layer, multi-functional coating prepared with metal-modified zinc phosphate, but the coating's solar reflectance and acid / alkali resistance still need improvement. CN109456668A, "A Weather-Resistant Reflective Heat-Insulating Coating and its Preparation Method," improves the coating's solar reflectance and weather resistance by adding silver-plated glass flakes. Patent CN107880675A, "A High-Performance Hollow Glass Microsphere Heat-Insulating Coating and its Preparation Method," describes a high-performance hollow glass microsphere heat-insulating coating that, when applied to building exterior walls, can reduce the "indoor" ambient temperature. Summary of the Invention

[0005] To address the problems in the prior art, this invention provides a water-based thermal insulation coating and its preparation method. The coating provided by this invention combines three mechanisms of action: radiation, reflection, and barrier properties. By controlling the particle size and amount of filler, the coating exhibits excellent thermal insulation, high adhesion, and strong corrosion resistance.

[0006] To solve the above-mentioned technical problems and achieve the technical features of the present invention, the following technical solution is provided:

[0007] According to a first aspect of the present invention, the present invention provides a water-based thermal insulation coating, the water-based thermal insulation coating comprising the following components in parts by weight:

[0008] Hollow glass microspheres I, 5-10 parts;

[0009] Hollow glass microspheres II, 15-20 parts;

[0010] Titanium dioxide, 10-20 parts;

[0011] Emulsion, 30-45 parts;

[0012] Modified carbon nanotubes, 0.1-2.5 parts;

[0013] Additives, 1-8 parts;

[0014] Water, 10-25 parts.

[0015] Furthermore, the hollow glass microspheres I have a particle size of 60-120 μm, preferably 70-100 μm; and the hollow glass microspheres II have a particle size of 1-50 μm, preferably 10-40 μm.

[0016] Furthermore, the titanium dioxide is rutile type with an average particle size of 0.3-20 μm.

[0017] Furthermore, the emulsion is one or more of styrene-acrylic emulsion, pure acrylic emulsion, polyurethane emulsion, or fluorocarbon emulsion; preferably, the emulsion is two or more of the above-mentioned emulsions.

[0018] Furthermore, the water-based coating also includes a curing agent, the weight of which is 1 / 10 to 1 / 8 of the total weight of the coating. Furthermore, the required curing agent is a commercially available water-based curing agent.

[0019] Furthermore, the modified carbon nanotubes are carbon nanotubes modified with Triton surfactant.

[0020] Further, the additives include dispersants, defoamers, neutralizers, multifunctional additives, and thickeners. Preferably, each additive includes one or more different types. All additives are selected from conventional additives in the art. Preferably, the dispersant includes dispersant 1 and dispersant 2. Dispersant 1 has an acid value of 8 mg KOH / g or higher (e.g., BYK-190), and dispersant 2 has an acid value of less than 7 mg KOH / g (e.g., BYK-2012). Preferably, the acid value difference between dispersant 1 and dispersant 2 is 2 mg KOH / g or higher, and the mass ratio of dispersant 1 to dispersant 2 is 7-10:1. Preferably, the thickener includes thickener 1 and thickener 2. Thickener 1 has a viscosity (25°C) of less than 16000 mPa·s (e.g., Hemings 420), and thickener 2 has a viscosity greater than 20000 mPa·s (e.g., Wanhua Chemical U605). Preferably, the viscosity difference between thickener 1 and thickener 2 is greater than 5000 mPa·s, and the mass ratio of thickener 1 to thickener 2 is approximately 1.5-5.5:1. In the aforementioned additives, the mass ratio of dispersant to thickener is generally 3-5:1. The multifunctional additive possesses functions such as wetting, anti-settling, leveling, and anti-sagging.

[0021] Furthermore, the modified carbon nanotubes can be prepared using conventional methods in the art. In this invention, the following preparation method is recommended. The preparation method of the modified carbon nanotubes includes the following steps:

[0022] (1) Add carbon nanotubes to a ball mill jar for ball milling;

[0023] (2) Disperse the carbon nanotubes after ball milling in step (1) in an aqueous solution containing Triton to obtain a carbon nanotube suspension;

[0024] (3) The carbon nanotube suspension obtained in step (2) is ultrasonically dispersed;

[0025] (4) After separation, washing and drying of the suspension obtained in step (3), Triathon-modified carbon nanotube powder can be obtained.

[0026] Furthermore, in step (1), the ball milling time can generally be 20-40 min.

[0027] Furthermore, the mass fraction of the Triton aqueous solution in step (2) is generally 1-3 wt%; the concentration of the suspension obtained in step (2) is generally 0.3-0.5 g / L.

[0028] Furthermore, in step (3), the dispersion time can generally be 20-40 min.

[0029] According to a second aspect of the present invention, the present invention also provides a method for preparing the above-mentioned water-based heat-insulating coating.

[0030] The preparation method of the water-based heat-insulating coating includes the following steps:

[0031] (1) Add the designed amount of dispersant, defoamer and neutralizer to the water in sequence while stirring, stir for a period of time, and then add the designed amount of titanium dioxide and disperse evenly.

[0032] (2) Grind the material obtained in step (1) to obtain titanium dioxide slurry;

[0033] (3) Add a portion of the designed amount of neutralizer to the titanium dioxide powder paste, add the emulsion, then add the defoamer and multifunctional additive, and stir for a period of time; while stirring, slowly add the designed amount of hollow glass microspheres I, and then slowly add the designed amount of hollow glass microspheres II, and continue stirring.

[0034] (4) Add water to prepare modified carbon nanotube slurry, disperse it fully, and obtain a uniformly dispersed surface-modified carbon nanotube dispersion; add the modified carbon nanotube dispersion to the material in step (3) and continue stirring for a period of time.

[0035] (5) Then add the remaining dispersant, multifunctional additive and thickener, and stir evenly to obtain the water-based heat insulation coating.

[0036] Furthermore, in step (1), the stirring time is generally 20-40 minutes. The stirring speed is generally 1000-1500 r / min.

[0037] Furthermore, in step (2), the material obtained in step (1) is generally ground to a fineness of less than 60 μm.

[0038] Furthermore, in step (3), the stirring time is 10-30 minutes before adding the hollow microspheres, and the stirring time continues for 10-20 minutes after adding the hollow microspheres. The stirring rate is generally 300-600 r / min.

[0039] Further, in step (4), the concentration of the modified carbon nanotube slurry is 0.5-8 g / L. Preferably, the dispersion is performed by ultrasonic dispersion, and the ultrasonic dispersion time is 0.5-2 h. The stirring time is 5-20 min. The stirring rate is generally 400-700 r / min.

[0040] Furthermore, the emulsion mentioned in step (3) is one or more of styrene-acrylic emulsion, pure acrylic emulsion, polyurethane emulsion, or fluorocarbon emulsion; preferably, the emulsion is a two-component emulsion. The required curing agent is a commercially available water-based curing agent.

[0041] Furthermore, the dispersant added in step (1) is dispersant 1, and the dispersant added in step (5) is dispersant 2. The addition ratio of dispersant 1 to dispersant 2 is approximately 7-10:1.

[0042] Furthermore, the thickener added in step (5) includes thickener 1 and thickener 2, and the addition ratio of thickener 1 and thickener 2 is approximately 1.5-5.5:1.

[0043] Furthermore, the hollow glass microspheres I have a particle size of 60-120 μm, preferably 70-100 μm; and the hollow glass microspheres II have a particle size of 1-50 μm, preferably 10-40 μm.

[0044] Furthermore, the modified carbon nanotubes are carbon nanotubes modified by Triathon surface modification.

[0045] Furthermore, the water mentioned is deionized water.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] 1. This invention uses two types of hollow microspheres, I and II, with different particle sizes, added together, and the content of smaller microspheres is controlled to be greater than that of larger microspheres. The addition of a larger quantity of smaller hollow microspheres effectively fills the gaps between the larger hollow microspheres, resulting in a denser microsphere packing and improved reflectivity. The reduced gaps between the hollow microspheres and the resin allow heat conduction to be converted into heat convection, increasing the thermal insulation effect of the coating. Simultaneously, the two different sized hollow microspheres can be completely coated by the resin and uniformly dispersed within it, further enhancing the thermal insulation effect of the coating.

[0048] 2. By adding appropriate proportions of different additives, especially the use of two specific proportions of dispersant and thickener, the present invention enables hollow microspheres of different particle sizes to be fully and uniformly dispersed with modified carbon nanotubes and titanium dioxide in the resin, resulting in good film formation and fluidity, and effectively improving the heat insulation, acid and alkali resistance and water resistance of the coating.

[0049] 3. In the water-based anti-corrosion and heat-insulating coating of the present invention, carbon nanotubes modified by the Triton surface can be better dispersed in the solution, providing good anti-corrosion and radiation performance; hollow microspheres can provide good heat insulation performance; and titanium dioxide can provide good reflective performance. The three fillers work together to form a heat insulation effect of radiation + barrier + reflection, thereby improving the heat insulation performance of the water-based heat-insulating coating of the present invention.

[0050] 4. The water-based thermal insulation coating of this invention is a single-layer, multi-functional coating with excellent anti-corrosion and thermal insulation properties, which is conducive to the promotion and utilization of the water-based thermal insulation coating product of this invention. At the same time, the preparation and construction process of the coating product of this invention is simple and easy to implement, solving the problems of poor interlayer matching, long construction cycle, strong odor and high pollution of traditional oil-based paints, while ensuring various anti-corrosion and thermal insulation indicators.

[0051] 5. The water-based heat insulation coating of the present invention adopts a water dispersion system, using water as a solvent to disperse the resin and filler system in water. When the coating film is cured, it mainly evaporates as water, which does not pollute the atmosphere. Implementation

[0052] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with specific embodiments.

[0053] The above-described solution will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. The implementation conditions used in the embodiments may be further adjusted according to the conditions of specific manufacturers, and the implementation conditions not specified are generally those in routine experiments.

[0054] The materials and reagents used in the following examples are all commercially available. Dispersant 1 is BYK-190, dispersant 2 is BYK-2012, defoamer is BYK-011, neutralizer is dimethylethanolamine, multifunctional additives include dipropylene glycol butyl ether and dipropylene glycol methyl ether, thickener 1 is Hemings 420, and thickener 2 is Wanhua Chemical U605.

[0055] This invention provides a water-based thermal insulation coating for petrochemical storage tanks and its preparation method. For specific material dosages and experimental procedures, please refer to the following examples. Example 1

[0056] Hollow glass microspheres I, 5 parts;

[0057] Hollow glass microspheres II, 15 parts;

[0058] Titanium dioxide, 15 parts;

[0059] Fluorocarbon emulsion, 40 parts;

[0060] Modified carbon nanotubes, 1 part;

[0061] Additives, 5 parts;

[0062] Water, 19 portions;

[0063] The additives are commercially available dispersants 1 and 2, defoamers, neutralizers, multifunctional additives, thickeners 1 and 2.

[0064] The preparation method of the above-mentioned modified carbon nanotubes is as follows:

[0065] (1) Add a certain amount of carbon nanotubes into a ball mill jar and ball mill for 30 min;

[0066] (2) Add a 2 wt% Triton aqueous solution to dilute to 0.4 g / L to obtain a carbon nanotube suspension;

[0067] (3) Disperse the suspension in an ultrasonic pulverizer for 30 min;

[0068] (4) The suspension is filtered through a filter membrane, and after washing and drying, the Triathon-modified carbon nanotube powder can be obtained.

[0069] The preparation method of the above-mentioned water-based heat insulation coating is as follows:

[0070] (1) Add the designed amount of dispersant 1, defoamer and neutralizer to the water in sequence at a stirring speed of 1200r / min, stir for 30 min, and then add the designed amount of titanium dioxide and disperse evenly.

[0071] (2) Grind again until the fineness is less than 60 μm to obtain a color paste;

[0072] (3) After adding neutralizer to color paste, add fluorocarbon emulsion, then add defoamer and multifunctional additive, stir for 20 minutes, then slowly add the designed amount of hollow glass microspheres I at a stirring speed of 500 r / min, and then slowly add the designed amount of hollow glass microspheres II, and stir.

[0073] (4) Add water to prepare a 2 g / L modified carbon nanotube slurry, and after ultrasonic dispersion for 1 h, a uniformly dispersed modified carbon nanotube dispersion is obtained. Add the modified carbon nanotube dispersion to the color paste in step (3). The stirring time is 15 min, and the stirring is carried out for 10 min at a stirring speed of 500 r / min.

[0074] (5) Finally, add dispersant 2, multifunctional additive, thickener 1 and thickener 2, and stir evenly to obtain water-based heat insulation coating. Example 2

[0075] A water-based heat-insulating coating, comprising the following parts by weight:

[0076] Hollow glass microspheres I, 10 parts;

[0077] Hollow glass microspheres II, 15 parts;

[0078] Titanium dioxide, 20 parts;

[0079] Polyurethane emulsion, 35 parts;

[0080] Additives, 5 parts;

[0081] Modified carbon nanotubes, 0.5 parts;

[0082] Water, 14.5 parts;

[0083] The additives are commercially available dispersants 1 and 2, defoamers, neutralizers, multifunctional additives, thickeners 1 and 2.

[0084] The preparation method of the modified carbon nanotubes is the same as in Example 1.

[0085] The preparation method of the above-mentioned water-based heat insulation coating is as follows:

[0086] (1) Add the designed amount of dispersant 1, defoamer and neutralizer to the water in sequence at a stirring speed of 1400r / min, stir for 20 min, and then add the designed amount of titanium dioxide and disperse evenly.

[0087] (2) Grind again until the fineness is less than 60 μm to obtain a color paste;

[0088] (3) After adding the neutralizer to the color paste, add the polyurethane emulsion, then add the defoamer and multifunctional additives. Stir for 15 minutes, then slowly add the designed amount of hollow glass microspheres I at a stirring speed of 400 r / min, and then slowly add the designed amount of hollow glass microspheres II. Stir.

[0089] (4) Add water to prepare a 3 g / L modified carbon nanotube slurry, and after ultrasonic dispersion for 1 h, a uniformly dispersed modified carbon nanotube dispersion is obtained. The surface-modified carbon nanotube dispersion is added to the color paste in step (3). The stirring time is 15 min, and the stirring is carried out at a stirring speed of 500 r / min for 15 min.

[0090] (5) Finally, add dispersant 2, multifunctional additive, thickener 1 and thickener 2, and stir evenly to obtain water-based heat insulation coating. Example 3

[0091] A water-based heat-insulating coating, comprising the following parts by weight:

[0092] Hollow glass microspheres I, 8 parts;

[0093] Hollow glass microspheres II, 18 parts;

[0094] Titanium dioxide, 12 parts;

[0095] Polyurethane emulsion, 38 parts;

[0096] Additives, 8 parts;

[0097] Modified carbon nanotubes, 0.2 parts;

[0098] Water, 15.8 parts.

[0099] The preparation method of the modified carbon nanotubes is the same as in Example 1.

[0100] The preparation method of the above-mentioned water-based heat insulation coating is the same as that in Example 2.

[0101] Comparative Example 1

[0102] This comparative example does not contain hollow glass microspheres I; all hollow microspheres are hollow microspheres II, and the rest is the same as in Example 1.

[0103] Comparative Example 2

[0104] This comparative example does not contain hollow glass microspheres II; all hollow microspheres are hollow microspheres I, and the rest is the same as in Example 1.

[0105] Comparative Example 3

[0106] In this comparative example, only 5 parts of titanium dioxide were added; the rest were the same as in Example 1.

[0107] Comparative Example 4

[0108] In this comparative example, a common carbon nanotube dispersion was used, and the rest was the same as in Example 1.

[0109] Comparative Example 5

[0110] In this comparative example, hollow glass microspheres I consisted of 15 parts, hollow glass microspheres II consisted of 5 parts, and the rest were the same as in Example 1.

[0111] Comparative Example 6

[0112] In this comparative example, the modified carbon nanotube slurry content was 4 parts, and the rest was the same as in Example 1.

[0113] Comparative Example 7

[0114] In this comparative example, only dispersant 1 was added to the additives; the rest were the same as in Example 1.

[0115] Comparative Example 8

[0116] In this comparative example, only thickener 1 was added to the additives; the rest were the same as in Example 1.

[0117] Comparative Example 9

[0118] In this comparative example, the carbon nanotubes were commercially available aminated modified carbon nanotubes, and the rest were the same as in Example 1.

[0119] The compositions of the coatings prepared in Examples 1-3 and Comparative Examples 1-9 are listed in Table 1.

[0120] Table 1. Composition of Coatings (Unit: Parts by Weight)

[0121] Hollow glass microspheres I Hollow Glass Microspheres II Titanium dioxide Fluorocarbon / polyurethane emulsion Additives Modified carbon nanotubes water Example 1 5 15 15 40 5 1 19 Example 2 10 15 20 35 5 0.5 14.5 Example 3 8 18 12 38 8 0.2 15.8 Comparative Example 1 0 20 15 40 5 1 19 Comparative Example 2 20 0 15 40 5 1 19 Comparative Example 3 5 15 5 40 5 1 29 Comparative Example 4 5 15 15 40 5 1 (Ordinary carbon nanotubes) 20 Comparative Example 5 15 5 15 40 5 1 19 Comparative Example 6 5 15 15 40 5 4 16 Comparative Example 7 5 15 15 40 5 (Contains only dispersant 1) 1 19 Comparative Example 8 5 15 15 40 5 (Contains thickener 1 only) 1 19 Comparative Example 9 5 15 15 40 5 1 (Commercially available aminated modified carbon nanotubes) 19

[0122] The coatings prepared in Examples 1-3 and Comparative Examples 1-9 were tested for reflectivity (test method according to JG / T235), hemispherical emissivity (test method according to GB / T 2680), and chemical resistance (test method according to GB / T9274). The results are shown in Table 2.

[0123] Table 2 Comparison of Test Results

[0124] Serial Number Reflectivity / % hemispherical emissivity / % <![CDATA[Acid resistance (5% H2SO4)]]> Alkali resistant (5% NaOH) Salt water resistance (3% NaCl) Example 1 90.3 87 No change in paint film after soaking for 720 hours No change in paint film after soaking for 192 hours No change in paint film after soaking for 192 hours Example 2 89.2 89 No change in paint film after soaking for 720 hours No change in paint film after soaking for 192 hours No change in paint film after soaking for 192 hours Example 3 89.6 85 No change in paint film after soaking for 720 hours No change in paint film after soaking for 192 hours No change in paint film after soaking for 192 hours Comparative Example 1 83.0 85 After soaking for 720 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 192 hours, the paint film showed signs of loss of gloss and blistering. No change in paint film after soaking for 192 hours Comparative Example 2 82.0 85 After soaking for 720 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 192 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 192 hours, the paint film showed signs of loss of gloss and blistering. Comparative Example 3 78.0 80 After soaking for 672 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 144 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 144 hours, the paint film showed signs of loss of gloss and blistering. Comparative Example 4 87.0 74 After soaking for 660 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 120 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 144 hours, the paint film showed signs of loss of gloss and blistering. Comparative Example 5 86.0 84 After soaking for 720 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 192 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 192 hours, the paint film showed signs of loss of gloss and blistering. Comparative Example 6 88.6 84 After soaking for 720 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 192 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 192 hours, the paint film showed signs of loss of gloss and blistering. Comparative Example 7 87.4 82 After soaking for 672 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 168 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 168 hours, the paint film showed signs of loss of gloss and blistering. Comparative Example 8 88.1 83 After soaking for 696 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 168 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 168 hours, the paint film showed signs of loss of gloss and blistering. Comparative Example 9 87.2 75 After soaking for 660 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 120 hours, the paint film showed signs of loss of gloss and blistering. After soaking for 144 hours, the paint film showed signs of loss of gloss and blistering.

[0125] As can be seen from the results of the examples in Table 2, the water-based reflective heat-insulating coating prepared by the present invention has good heat insulation performance, as well as excellent acid and alkali resistance. Comparing the examples with Comparative Examples 1 and 2, the reflectivity of the coating with only single-size hollow glass microspheres decreased, while the changes in hemispherical emissivity and acid / alkali resistance were minimal. Analysis of Comparative Example 3 showed that reducing the titanium dioxide content reduced the coating's reflectivity, hemispherical emissivity, acid / alkali resistance, and water resistance. Comparative Example 4 showed that replacing the modified carbon nanotubes with ordinary carbon nanotubes significantly reduced the coating's hemispherical emissivity, and also decreased its acid / alkali resistance and water resistance. Comparative Example 5 showed that when the content of large-size hollow glass microspheres I was much greater than that of small-size hollow glass microspheres II, the coating's reflectivity decreased, but it had virtually no effect on the coating's hemispherical emissivity, acid / alkali resistance, and water resistance. Comparative Example 6 showed that when the content of the added modified carbon nanotubes increased to 4 parts, the coating's hemispherical emissivity was not at its maximum, indicating that excessive carbon nanotube content would not increase the hemispherical emissivity of the coating; instead, it would decrease it. As shown in Comparative Example 7, when only dispersant 1 is used, the reflectivity, hemispherical emissivity, acid and alkali resistance, and water resistance of the coating are all reduced. As shown in Comparative Example 8, when only thickener 1 is used, the reflectivity, hemispherical emissivity, acid and alkali resistance, and water resistance of the coating are all reduced compared with the examples. As shown in Comparative Example 9, when the Triathon modified carbon nanotubes are replaced with ordinary aminated modified carbon nanotubes, the hemispherical emissivity of the coating is significantly reduced, and the acid and alkali resistance and water resistance are also reduced.

[0126] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. For those skilled in the art, several improvements can be made without departing from the principle of the present invention, and these improvements should also be considered within the scope of protection of the present invention.

Claims

1. A water-based thermal barrier coating, characterized by, Comprise the following components by weight: Hollow glass microbeads I, 5-10 parts; Hollow glass microbeads II, 15-20 parts; Titanium white, 10-20 parts; Emulsion, 30-45 parts; Modified carbon nanotubes, 0.1-2.5 parts; Auxiliary agent, 1-8 parts; Water, 10-25 parts; The particle size of the hollow glass microbeads I is 60-120 μm; the particle size of the hollow glass microbeads II is 1-50 μm; The auxiliary agent comprises a dispersing agent, a defoaming agent, a neutralizing agent, a multifunctional auxiliary agent, and a thickening agent; The dispersing agent comprises a dispersing agent 1 and a dispersing agent 2, the acid value of the dispersing agent 1 is more than 8 mg KOH / g, and the acid value of the dispersing agent 2 is less than 7 mg KOH / g; The thickening agent comprises a thickening agent 1 and a thickening agent 2; the viscosity of the thickening agent 1 at 25℃ is less than 16000 mPa·s, and the viscosity of the thickening agent 2 at 25℃ is more than 20000 mPa·s; The modified carbon nanotubes are carbon nanotubes modified by Triton surfactant.

2. The water-based thermal barrier coating according to claim 1, characterized in that, The particle size of the hollow glass microbeads I is 70-100 μm; the particle size of the hollow glass microbeads II is 10-40 μm.

3. The water-based thermal barrier coating according to claim 1, characterized in that, The titanium white is of rutile type, and the average particle size is 0.3-20 μm.

4. The water-based thermal barrier coating according to claim 1, characterized in that, The emulsion is one or more of benzene propyl emulsion, pure propyl emulsion, polyurethane emulsion, or fluorocarbon emulsion.

5. The water-based thermal barrier coating according to claim 1, characterized in that, The mass ratio of the dispersing agent and the thickening agent is 3-5:

1.

6. The water-based thermal barrier coating according to claim 1, characterized in that, The mass ratio of the dispersing agent 1 and the dispersing agent 2 is 7-10:

1.

7. The water-based thermal barrier coating according to claim 1, characterized in that, The mass ratio of the thickening agent 1 and the thickening agent 2 is 1.5-5.5:

1.

8. The water-based thermal barrier coating according to claim 1, characterized in that, The preparation method of the modified carbon nanotubes comprises the following steps: (1) carbon nanotubes are added into a ball mill tank for ball milling; (2) the carbon nanotubes ball-milled in step (1) are dispersed in a Triton-containing aqueous solution to obtain a carbon nanotube suspension; (3) the carbon nanotube suspension obtained in step (2) is subjected to ultrasonic dispersion; (4) the suspension obtained in step (3) is separated, washed, and dried to obtain Triton-modified carbon nanotube powder.

9. The water-based thermal barrier coating according to claim 8, characterized in that, The mass fraction of the Triton-containing aqueous solution in step (2) is 1-3 wt%; the concentration of the suspension obtained in step (2) is 0.3-0.5 g / L.

10. Aqueous thermal barrier coating according to any one of claims 1 to 9, characterized in that The water-based thermal insulation coating further comprises a curing agent, and the weight of the curing agent is 1 / 10-1 / 8 of the total amount of the coating.

11. A process for the preparation of the water-based thermal barrier coating according to any one of claims 1 to 9, characterized in that, Comprise the following steps: (1) under stirring, a designed amount of dispersing agent 1, defoaming agent, and neutralizing agent are sequentially added into water, stirred for a period of time, then a designed amount of titanium white is added, and uniformly dispersed; (2) the material obtained in step (1) is ground to prepare a titanium white color paste; (3) a part of the designed amount of neutralizing agent is added into the titanium white color paste, then emulsion is added, and defoaming agent and multifunctional auxiliary agent are added, stirred for a period of time; Under stirring, a designed amount of hollow glass microbeads I is slowly added, then a designed amount of hollow glass microbeads II is slowly added, and stirring is continued; (4) water is added to prepare a modified carbon nanotube slurry, fully dispersed, to obtain a uniformly dispersed surface-modified carbon nanotube dispersion; the modified carbon nanotube dispersion is added into the material in step (3), and stirring is continued for a period of time; (5) Then continue to add dispersant 2, multifunctional additive, thickening agent 1 and thickening agent 2, and after stirring evenly, the water-based thermal insulation coating is obtained.

12. The preparation method according to claim 11, characterized in that, The material obtained in step (1) is ground to a fineness of less than 60 μm in step (2).

13. The preparation method according to claim 11, characterized in that, The stirring time in step (3) is 10-30 min before the hollow glass microsphere I is added, and the stirring time is 10-20 min after the hollow glass microsphere II is added.

14. The preparation method according to claim 11, characterized in that, The concentration of the modified carbon nanotube slurry in step (4) is 0.5-8 g / L.

15. The preparation method according to claim 11, characterized in that, The dispersion in step (4) is ultrasonic dispersion, and the ultrasonic dispersion time is 0.5-2 h.