Thermal insulation coating and preparation method thereof

Abstract

The invention discloses a thermal insulation coating and a preparation method thereof, and belongs to the technical field of coating preparation. The preparation method comprises the following steps: mixing the perforated hollow ceramic microbeads with the basic coating, and carrying out first stirring; adding the silk fibroin solution, the light stabilizer, the flatting agent, the coupling agent, the preservative and the water, and performing secondary stirring; adding the coalescing agent, stirring for the third time, and filtering to obtain the product. The obtained thermal insulation coating comprises the following components in parts by weight: 45-55 parts of perforated hollow ceramic microbeads, 45-55 parts of a basic coating, 3-6 parts of a silk fibroin solution, 3-6 parts of a light stabilizer, 1-3 parts of a flatting agent, 3-6 parts of a coupling agent, 0.5-1 part of a preservative, 25-35 parts of water, 1-4 parts of a coalescing agent and the like. By introducing the perforated hollow ceramic microbeads, the modification additive and the corresponding preparation process, the production cost of the prepared thermal insulation coating is remarkably reduced, and the thermal insulation coating has higher strength and scratch resistance.

Description

Technical Field

[0001] The invention belongs to the technical field of coating preparation, and in particular relates to a thermal insulation coating and a preparation method thereof. Background Art

[0002] With the strengthening of environmental protection concepts and the increasing prominence of energy shortages, energy conservation and emission reduction have become the current and future trends, and energy conservation and emission reduction are imperative. Thermal insulation coatings are widely used in energy conservation and emission reduction, with significant effects.

[0003] At present, there are two main mechanisms for thermal insulation coatings to achieve thermal insulation function. One is to add hollow microspheres to achieve low thermal conductivity. Depending on the purpose and scenario of the coating, hollow microspheres are used alone or in combination, such as floating beads, hollow glass microspheres or hollow ceramic microspheres. The other mechanism is that the coating reacts and foams during the later use process, thereby achieving low thermal conductivity.

[0004] Floating beads are low cost and widely available, but they have low strength and their operating temperature is below 500°C. Compared with floating beads, hollow glass beads have significantly improved strength, but the operating temperature has not changed, and the cost has increased ten to dozens of times. Hollow ceramic beads have excellent comprehensive properties such as strength and heat resistance, but their cost is slightly higher than hollow glass beads.

[0005] Reaction foaming generally needs to be achieved at a certain temperature, which limits its application in the room temperature range.

[0006] According to the above analysis, there is an urgent need for a thermal insulation coating with good thermal insulation performance, low cost, high strength, and good thermal insulation performance at room temperature. The price of open-pore ceramic microspheres is close to that of floating beads, and much lower than that of hollow glass microspheres and hollow ceramic microspheres, but the performance is similar to the latter two. Therefore, the thermal insulation coating based on open-pore ceramic microspheres proposed in the present invention has good cost performance and broad market prospects. Summary of the invention

[0007] The purpose of the present invention is to provide a thermal insulation coating and a preparation method thereof. By introducing open-pore hollow ceramic microspheres and a modified additive and a corresponding preparation process, the production cost of the thermal insulation coating is significantly reduced, and the thermal insulation coating has higher strength and scratch resistance.

[0008] To achieve the above objectives, the present invention adopts the following specific technical solutions:

[0009] A method for preparing a thermal insulation coating comprises the following steps: mixing open-pore hollow ceramic microbeads with a base coating and performing a first stirring; adding a silk fibroin solution, a light stabilizer, a leveling agent, a coupling agent, a preservative and water and performing a second stirring; adding a film-forming aid and performing a third stirring, and filtering to obtain the coating.

[0010] Furthermore, the light stabilizer includes epoxy soybean oil; the leveling agent includes polyether modified silicone leveling agent or BZ-333; the coupling agent includes KH550 or KH560; the preservative includes LD05; and the film-forming aid includes 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate.

[0011] Preferably, the open-pore hollow ceramic microspheres are subjected to surface modification treatment before being mixed with the base coating, so as to increase the compatibility with the base coating and improve the strength of the film layer after film formation.

[0012] Furthermore, the surface modification treatment includes: placing the open-pore hollow ceramic microspheres in a mixing device, spraying a modification aid by spraying while stirring, continuing to stir for 20-60 minutes after spraying, and baking at 80-120° C. for 60-90 minutes.

[0013] Preferably, the modification aid accounts for 0.1-0.3% of the mass of the open-pore hollow ceramic microspheres.

[0014] More preferably, the surface-modified open-pore hollow ceramic microspheres are placed in a mixing device again, and the surface modification process is repeated at least once to obtain open-pore hollow ceramic microspheres having at least two modified layers. It is understandable that limiting the number of repetitions of the surface modification process to 2-3 times is advantageous, but not more, otherwise it will affect the use of the coating and increase the cost.

[0015] Preferably, the modification aid is a mixture of BYK-C 8000 and alcohol in a mass ratio of 1:8-12.

[0016] Preferably, the open-pore hollow ceramic microspheres include hollow ceramic microspheres having a plurality of closed small cavities inside and / or hollow ceramic microspheres having a single large cavity inside, which have better thermal insulation performance.

[0017] Preferably, the particle size of the open-pore hollow ceramic microspheres is 10-200 μm, the surface porosity is ≥ 20%, and the bulk density is 0.4-0.8 g / cm 3 The overall porosity is 20-50%, and its open-pore structure is conducive to interaction with the modified additives, and the binding force is stronger.

[0018] Furthermore, the base coating comprises, by weight, 45-55 parts of styrene acrylic emulsion, 3-10 parts of nano functional filler and 5-15 parts of reinforcing ceramic fiber.

[0019] The nano-functional filler preferably includes one or more of fumed silica, zinc oxide, titanium oxide, etc. The reinforcing ceramic fiber preferably includes alumina fiber and / or aluminum silicate fiber.

[0020] Preferably, the preparation method of the base coating comprises: stirring and mixing the styrene acrylic emulsion, nano functional filler, reinforcing ceramic fiber and dispersant at a speed of 1000-1500 r / min, and after 10-15 minutes, stirring and mixing at a speed of 100-120 r / min to obtain the base coating.

[0021] Preferably, the stirring rates of the first stirring, the second stirring and the third stirring are all low-speed stirring of 100-300 r / min. In particular, the first stirring at a low speed can effectively prevent the open-pore hollow ceramic microspheres or modified open-pore hollow ceramic microspheres from being damaged, thereby affecting product performance.

[0022] The present invention also provides a thermal insulation coating obtained by the preparation method, which comprises, by weight, 45-55 parts of the open-pore hollow ceramic microbeads, 45-55 parts of the base coating, 3-6 parts of the silk fibroin solution, 3-6 parts of a light stabilizer, 1-3 parts of a leveling agent, 3-6 parts of a coupling agent, 0.5-1 parts of a preservative, 25-35 parts of water, 1-4 parts of a film-forming aid, and the like.

[0023] Compared with the prior art, the present invention introduces open-pore hollow ceramic microspheres and modification additives and their corresponding preparation processes, and utilizes the open-pore structure of the open-pore hollow ceramic microspheres and the modification additives to improve the compatibility with the base coating. The two interact with each other to obtain a thermal insulation coating with stronger bonding strength. Without lowering the operating temperature, the production cost is significantly reduced, and the coating has higher strength and scratch resistance. DETAILED DESCRIPTION

[0024] The embodiments of the present invention will be described in detail below in conjunction with specific examples, but it will be appreciated by those skilled in the art that the following examples are only used to illustrate the present invention and should not be considered to limit the scope of the present invention. If specific conditions are not specified in the examples, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0025] Example 1

[0026] A method for preparing a thermal insulation coating comprises the following steps:

[0027] (1) Place the open-pored hollow ceramic microbeads in a high-efficiency powder mixer, and spray a modified auxiliary agent prepared by mixing BYK-C 8000 and alcohol in a mass ratio of 1:10 through the spray head of the high-efficiency powder mixer, and stir at room temperature. After the spraying is completed, continue stirring for more than 30 minutes, and then discharge the material; the modified open-pored hollow ceramic microbeads are baked at 90°C for more than 60 minutes to remove the alcohol, and then cooled to obtain the modified open-pored hollow ceramic microbeads for use. The amount of the modified auxiliary agent sprayed in accounts for 0.2% of the mass of the open-pored hollow ceramic microbeads. The open-pored hollow ceramic microbeads include hollow ceramic microbeads with multiple closed small cavities inside and hollow ceramic microbeads with a single large cavity inside, with a particle size of 50-200μm, a surface porosity of ≥50%, and a bulk density of 0.53g / cm 3 , the overall porosity is 43%.

[0028] (2) 50 g of the styrene-acrylic emulsion, 3 g of fumed silica, 3 g of zinc oxide, 3 g of titanium oxide, 10 g of alumina fiber and 5 g of dispersant SK-5040 were stirred and mixed at a speed of 1500 r / min. After 10 minutes, the mixture was stirred and mixed at a speed of 100 r / min to obtain a base coating for use.

[0029] (3) 50 g of modified open-pore hollow ceramic microspheres are mixed with 50 g of base coating, and stirred at a speed of 110 r / min; during the stirring process, 5 g of silk fibroin solution, 4 g of light stabilizer epoxy soybean oil, 2 g of polyether modified silicone leveling agent, 4 g of coupling agent KH550, 0.5 g of preservative LD05 and 30 g of water are added, and the mixture is stirred at a speed of 110 r / min; finally, 3 g of film-forming aid 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate is added, the mixture is stirred at a speed of 110 r / min, and the thermal insulation coating is obtained after filtering.

[0030] Example 2

[0031] A method for preparing a thermal insulation coating comprises the following steps:

[0032] (1) Place the open-pored hollow ceramic microbeads in a high-efficiency powder mixer, and spray a modified auxiliary agent prepared by mixing BYK-C 8000 and alcohol in a mass ratio of 1:12 through the spray head of the high-efficiency powder mixer, and stir at room temperature. After the spraying is completed, continue stirring for more than 30 minutes, and then discharge the material; the modified open-pored hollow ceramic microbeads are baked at 80°C for more than 60 minutes to remove the alcohol, and then cooled to obtain the modified open-pored hollow ceramic microbeads for use. The amount of the modified auxiliary agent sprayed in accounts for 0.3% of the mass of the open-pored hollow ceramic microbeads. The open-pored hollow ceramic microbeads include hollow ceramic microbeads with multiple closed small cavities inside and hollow ceramic microbeads with a single large cavity inside, with a particle size of 50-200μm, a surface porosity of ≥50%, and a bulk density of 0.47g / cm 3 , the overall porosity is 50%.

[0033] (2) 45 g of the styrene-acrylic emulsion, 2 g of fumed silica, 3 g of zinc oxide, 3 g of titanium oxide, 12 g of aluminum silicate fiber and 5 g of dispersant SK-5040 were stirred and mixed at a speed of 1200 r / min. After 15 minutes, the mixture was stirred and mixed at a speed of 120 r / min to obtain a base coating for use.

[0034] (3) 55 g of modified open-pore hollow ceramic microspheres were mixed with 55 g of base coating, and the mixture was stirred at a speed of 110 r / min; during the stirring process, 4 g of silk fibroin solution, 4 g of light stabilizer epoxy soybean oil, 3 g of leveling agent BZ-333, 4 g of coupling agent KH560, 0.5 g of preservative LD05 and 35 g of water were added, and the mixture was stirred at a speed of 110 r / min; finally, 2 g of film-forming aid 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate was added, the mixture was stirred at a speed of 110 r / min, and the thermal insulation coating was obtained after filtering.

[0035] Example 3

[0036] A method for preparing a thermal insulation coating comprises the following steps:

[0037] (1) Place the open-pored hollow ceramic microbeads in a high-efficiency powder mixer, and spray a modified auxiliary agent prepared by mixing BYK-C 8000 and alcohol in a mass ratio of 1:8 through the spray head of the high-efficiency powder mixer, and stir at room temperature. After the spraying is completed, continue stirring for more than 20 minutes, and then discharge the material; the modified open-pored hollow ceramic microbeads are baked at 110°C for more than 60 minutes to remove the alcohol, and then cool to obtain the modified open-pored hollow ceramic microbeads for use. The amount of the modified auxiliary agent sprayed in accounts for 0.1% of the mass of the open-pored hollow ceramic microbeads. The open-pored hollow ceramic microbeads include hollow ceramic microbeads with multiple closed small cavities inside and hollow ceramic microbeads with a single large cavity inside, with a particle size of 50-200μm, a surface porosity of ≥50%, and a bulk density of 0.56g / cm 3 , the overall porosity is 35%.

[0038] (2) 55 g of the styrene-acrylic emulsion, 3 g of fumed silica, 2 g of zinc oxide, 2 g of titanium oxide, 15 g of alumina fiber and 3 g of dispersant SK-5040 were stirred and mixed at a speed of 1000 r / min. After 12 minutes, the mixture was stirred and mixed at a speed of 100 r / min to obtain a base coating for use.

[0039] (3) 45 g of modified open-pore hollow ceramic microbeads were mixed with 45 g of base coating, and the mixture was stirred at a speed of 100 r / min; during the stirring process, 3 g of silk fibroin solution, 5 g of light stabilizer epoxy soybean oil, 1 g of polyether modified silicone leveling agent, 3 g of coupling agent KH550, 0.3 g of preservative LD05 and 25 g of water were added, and the mixture was stirred at a speed of 100 r / min; finally, 1.5 g of film-forming aid 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate was added, the mixture was stirred at a speed of 100 r / min, and the thermal insulation coating was obtained after filtering.

[0040] Example 4

[0041] A method for preparing a thermal insulation coating comprises the following steps:

[0042] (1) preparing open-pore hollow ceramic microspheres for standby use, wherein the open-pore hollow ceramic microspheres include hollow ceramic microspheres with multiple closed small cavities inside and hollow ceramic microspheres with a single large cavity inside, with a particle size of 50-200 μm, a surface open porosity of ≥50%, and a bulk density of 0.53 g / cm 3 , the overall porosity is 43%.

[0043] (2) 50 g of the styrene-acrylic emulsion, 3 g of fumed silica, 3 g of zinc oxide, 3 g of titanium oxide, 10 g of alumina fiber and 5 g of dispersant SK-5040 were stirred and mixed at a speed of 1500 r / min. After 10 minutes, the mixture was stirred and mixed at a speed of 100 r / min to obtain a base coating for use.

[0044] (3) Mix 50 g of open-pore hollow ceramic microbeads with 50 g of base coating, and stir and mix at a speed of 110 r / min; during the stirring process, add 5 g of silk fibroin solution, 4 g of light stabilizer epoxy soybean oil, 2 g of polyether-modified silicone leveling agent, 4 g of coupling agent KH550, 0.5 g of preservative LD05 and 30 g of water, and stir and mix at a speed of 110 r / min; finally, add 3 g of film-forming aid 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, stir and mix at a speed of 110 r / min, and obtain the thermal insulation coating after filtering.

[0045] Example 5

[0046] A method for preparing a thermal insulation coating comprises the following steps:

[0047] (1) Place the open-pored hollow ceramic microbeads in a high-efficiency powder mixer, and spray a modified auxiliary agent prepared by mixing BYK-C 8000 and alcohol in a mass ratio of 1:10 through the spray head of the high-efficiency powder mixer, and stir at room temperature. After the spraying is completed, continue stirring for more than 30 minutes, and then discharge the material; the modified open-pored hollow ceramic microbeads are baked at 90°C for more than 60 minutes to remove the alcohol, and then cooled to obtain the modified open-pored hollow ceramic microbeads for use. The amount of the modified auxiliary agent sprayed in accounts for 0.2% of the mass of the open-pored hollow ceramic microbeads. The open-pored hollow ceramic microbeads include hollow ceramic microbeads with multiple closed small cavities inside and hollow ceramic microbeads with a single large cavity inside, with a particle size of 50-200μm, a surface porosity of ≥50%, and a bulk density of 0.53g / cm 3 , the overall porosity is 43%.

[0048] (2) Repeating the modification process of step (1) with the first modified open-pored hollow ceramic microbeads obtained in step (1), wherein the injection amount of the modification aid is the same as that in step (1), to obtain open-pored hollow ceramic microbeads having two modified layers.

[0049] (3) 50 g of the styrene-acrylic emulsion, 3 g of fumed silica, 3 g of zinc oxide, 3 g of titanium oxide, 10 g of alumina fiber and 5 g of dispersant SK-5040 were stirred and mixed at a speed of 1500 r / min. After 10 minutes, the mixture was stirred and mixed at a speed of 100 r / min to obtain a base coating for use.

[0050] (4) Mix 50 g of the open-pored hollow ceramic microbeads of the second modified layer obtained in step (2) with 50 g of the base coating, and stir and mix at a speed of 110 r / min; during the stirring process, add 5 g of silk fibroin solution, 4 g of light stabilizer epoxy soybean oil, 2 g of polyether modified silicone leveling agent, 4 g of coupling agent KH550, 0.5 g of preservative LD05 and 30 g of water, and stir and mix at a speed of 110 r / min; finally, add 3 g of film-forming aid 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, stir and mix at a speed of 110 r / min, and obtain the thermal insulation coating after filtering.

[0051] After testing, the performance comparison of the thermal insulation coatings obtained in Examples 1-5 is shown in Table 1.

[0052] Table 1 Comparison of thermal insulation coating properties obtained in Examples 1-5

[0053] Example Thermal conductivity (W / m·K) Emissivity (%) Solar reflectivity (%) Shear bond strength(KPa) 1 0.041 0.85 86 643 2 0.038 0.88 87 617 3 0.035 0.89 88 540 4 0.038 0.86 87 582 5 0.029 0.85 86 658

[0054] It can be seen that the thermal insulation material obtained by modifying the open-pored hollow ceramic microspheres in Examples 1-3 has significantly higher strength and improved scratch resistance than the thermal insulation material obtained by modifying the unmodified open-pored hollow ceramic microspheres in Example 4. After the open-pored hollow ceramic microspheres in Example 5 are modified twice, their strength is still significantly improved on the basis of Examples 1-3.

[0055] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention is described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the above embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention. In addition, those skilled in the art can understand that although some embodiments herein include certain features included in other embodiments instead of other features, the combination of features of different embodiments means being within the scope of the present invention and forming different embodiments. For example, in the above claims, any one of the embodiments claimed for protection can be used in any combination. The information disclosed in this background technology section is only intended to deepen the understanding of the overall background technology of the present invention, and should not be regarded as admitting or suggesting in any form that the information constitutes prior art known to those skilled in the art.

Claims

1. A method for preparing a thermal insulation coating, characterized in that: The open-pore hollow ceramic microbeads are mixed with the base coating and subjected to a first stirring; a silk fibroin solution, a light stabilizer, a leveling agent, a coupling agent, a preservative and water are added and subjected to a second stirring; a film-forming aid is added and subjected to a third stirring, and the mixture is filtered to obtain the product.

2. The preparation method according to claim 1, characterized in that: The open-pore hollow ceramic microspheres are first subjected to surface modification treatment before being mixed with the base coating, so as to increase the compatibility with the base coating and improve the strength of the film layer after film formation.

3. The preparation method according to claim 2, characterized in that: The surface modification treatment comprises: placing the open-pore hollow ceramic microspheres in a mixing device, spraying a modification additive by spraying while stirring, continuing to stir for 20-60 minutes after the spraying is completed, and baking at 80-120° C. for 60-90 minutes; Preferably, the modification aid accounts for 0.1-3% of the mass of the open-pore hollow ceramic microspheres.

4. The preparation method according to claim 3, characterized in that: The open-pore hollow ceramic microbeads after the surface modification treatment are placed in a mixing device again, and the surface modification treatment process is repeated at least once to obtain open-pore hollow ceramic microbeads with at least two modified layers.

5. The preparation method according to any one of claims 2 to 4, characterized in that: The modification auxiliary agent is obtained by mixing BYK-C 8000 and alcohol in a mass ratio of 1:8-12.

6. The preparation method according to claim 1, characterized in that: The open-pore hollow ceramic microbeads include hollow ceramic microbeads with a plurality of closed small cavities inside and / or hollow ceramic microbeads with a single large cavity inside.

7. The preparation method according to claim 1, characterized in that: The particle size of the open-pore hollow ceramic microspheres is 10-200 μm, the surface porosity is ≥20%, and the bulk density is 0.4-0.8 g / cm 3 , the overall porosity is 20-50%.

8. The preparation method according to claim 1, characterized in that: The base coating comprises, by weight, 45-55 parts of styrene acrylic emulsion, 3-10 parts of nano functional filler and 5-15 parts of reinforced ceramic fiber; Preferably, the nano-functional filler includes one or more of fumed silica, zinc oxide and titanium oxide; Preferably, the reinforced ceramic fibers include alumina fibers and / or aluminum silicate fibers; Preferably, the preparation method of the base coating comprises: stirring and mixing the styrene acrylic emulsion, nano functional filler and reinforced ceramic fiber at a rotation speed of 1000-1500 r / min, and after 10-15 minutes, stirring and mixing at a rotation speed of 100-120 r / min to obtain the base coating.

9. The preparation method according to claim 1, characterized in that: The stirring rates of the first stirring, the second stirring and the third stirring are all low-speed stirring of 100-300 r / min.

10. A thermal insulation coating obtained by the preparation method according to any one of claims 1 to 9, characterized in that: By weight, it comprises 45-55 parts of the open-pore hollow ceramic microbeads, 45-55 parts of the base coating, 3-6 parts of the silk fibroin solution, 3-6 parts of the light stabilizer, 1-3 parts of the leveling agent, 3-6 parts of the coupling agent, 0.5-1 parts of the preservative, and 25-35 parts of water.