Building exterior wall heat insulation coating and preparation method thereof

Abstract

The invention relates to the field of thermal insulation materials, in particular to a building exterior wall thermal insulation coating and a preparation method thereof, and aims to solve the problems that an existing building exterior wall thermal insulation coating is poor in thermal insulation performance and water resistance and cannot achieve a long-acting high thermal insulation effect. According to the preparation method, all the components are reasonably compounded, so that the coating can be well attached to the outer wall of a building, heat of the external environment transferred into the building can be effectively reduced, the comfortable temperature in the building is kept, energy consumption is reduced, the purposes of energy conservation and environmental protection are achieved, meanwhile, water permeation can be effectively prevented, and coating damage is avoided; the long-acting high heat insulation effect is achieved, water is prevented from permeating into the internal structure of a building, the building is protected against water damage, the service life of the building is remarkably prolonged, and meanwhile the overall attractiveness of the building is improved.

Description

Technical Field

[0001] This invention relates to the field of thermal insulation materials, specifically thermal insulation coatings for building exterior walls and their preparation methods. Background Technology

[0002] With the accelerating pace of urbanization, the number of buildings has increased dramatically, placing higher demands on building energy conservation and environmental protection. Especially during the hot summer months, building exterior walls absorb a large amount of solar radiation heat, leading to increased indoor temperatures and higher energy consumption for air conditioning, resulting in significant energy waste and environmental pollution. Furthermore, while existing insulation materials can reduce heat transfer to some extent, they easily lose their insulation effect when exposed to moisture, thus affecting the building's energy efficiency. Therefore, developing a building exterior wall insulation coating and its preparation method is of significant practical importance.

[0003] To address the aforementioned technical shortcomings, a solution is proposed. Summary of the Invention

[0004] In order to overcome the above-mentioned technical problems, the purpose of this invention is to provide a heat insulation coating for building exterior walls and its preparation method, which solves the problem that the existing heat insulation coatings for building exterior walls have poor heat insulation and water resistance properties and cannot achieve the purpose of long-term high heat insulation effect.

[0005] The objective of this invention can be achieved through the following technical solutions: In the first aspect, this application provides a building exterior wall thermal insulation coating, comprising the following components in parts by weight: The composition includes 25-30 parts of styrene-acrylic emulsion, 5-17 parts of modified composite heat insulation powder, 0.7-2.5 parts of hindered amine-grafted fluorescein compound, 10-12 parts of heavy calcium carbonate, 2-3 parts of antifreeze, 0.8-1 part of dispersant, 0.4-0.6 parts of defoamer, 0.3-0.5 parts of wetting agent, 0.2-0.3 parts of leveling agent, 0.7-1.1 parts of thickener, 1.8-2.6 parts of film-forming aid, and 30-35 parts of deionized water. The modified composite heat insulation powder is prepared by the following steps: Composite heat insulation powder, toluene, and silane coupling agent KH-560 were added to a three-necked flask equipped with a stirrer and thermometer. The mixture was stirred for 10-20 minutes at a temperature of 20-25℃ and a stirring rate of 200-300 r / min. The temperature was then raised to 60-65℃ and the stirring was continued for 2-3 hours. Deionized water and hydrochloric acid solution were then added and the mixture was stirred for another 4-6 hours. After the reaction was completed, the product was cooled to room temperature and centrifuged. The precipitate was washed 3-5 times with anhydrous ethanol and then placed in a vacuum drying oven and dried at 60-65℃ for 3-5 hours to obtain the modified composite heat insulation powder.

[0006] In a preferred embodiment of the present invention, the ratio of the composite heat insulation powder, toluene, silane coupling agent KH-560, deionized water and hydrochloric acid solution is 10g:90-100mL:1.5-7.5g:15-20mL:2-3mL.

[0007] In a preferred embodiment of the present invention, the composite heat insulation powder is a mixture of glass microspheres, nano titanium dioxide and nano zinc oxide in a mass ratio of 5:1-3:0.5-1.5; the hydrochloric acid solution has a mass fraction of 10-12%.

[0008] In a preferred embodiment of the present invention, the glass microspheres are 3M hollow glass microspheres K15; the nano titanium dioxide is anatase nano titanium dioxide with an average particle size of 5nm; and the nano zinc oxide is nano zinc oxide with an average particle size of 30nm.

[0009] In a preferred embodiment of the present invention, the hindered amine-grafted fluorescein compound is prepared by the following steps: Step A1: Add fluorescein, 3,5-bis(trifluoromethyl)aniline and anhydrous ethanol to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Purge with nitrogen for protection and stir the reaction at 20-25℃ and 200-300 r / min for 10-20 min. Then raise the temperature to 80-85℃ and continue stirring for 9-10 h. After the reaction is completed, cool the reaction product to room temperature, then remove the solvent by rotary evaporation, add it to distilled water, and then filter under vacuum. Place the filter cake in a vacuum drying oven and dry it at 60-65℃ for 2-3 h to obtain fluorescein fluorescein compound. Step A2: Add 2,2,6,6-tetramethylpiperidinamine, chloroacetyl chloride, triethylamine, and dichloromethane to a three-necked flask equipped with a stirrer and thermometer. Stir the reaction at 0-3℃ and 200-300 r / min for 10-20 min. Then raise the temperature to 20-25℃ and continue stirring for 2-3 h. Then raise the temperature to 50-55℃ and continue stirring for 3-4 h. After the reaction is complete, cool the reaction product to room temperature, wash it 3-5 times with distilled water, dry it with anhydrous magnesium sulfate, filter it under vacuum, and remove the solvent by rotary evaporation to obtain the hindered amine compound. Step A3: Add the fluorinated fluorescein compound, the hindered amine compound, anhydrous potassium carbonate, N,N-dimethylformamide, and toluene to a three-necked flask equipped with a stirrer, thermometer, and gas delivery tube. Purge with nitrogen for protection and stir the reaction at 20-25℃ and a stirring rate of 200-300 r / min for 30-60 min. Then, raise the temperature to 120-130℃ and continue stirring for 5-9 h. After the reaction is complete, cool the reaction product to room temperature and add it to distilled water. Adjust the pH to 6-6.5 with hydrochloric acid solution, then filter under vacuum. Place the filter cake in a vacuum drying oven and dry it at 60-65℃ for 3-5 h to obtain the hindered amine-grafted fluorescein compound.

[0010] In a preferred embodiment of the present invention, the ratio of fluorescein, 3,5-bis(trifluoromethyl)benzylamine and anhydrous ethanol in step A1 is 20 mmol: 25-30 mmol: 80-100 mL.

[0011] In a preferred embodiment of the present invention, the ratio of 2,2,6,6-tetramethylpiperidineamine, chloroacetyl chloride, triethylamine and dichloromethane in step A2 is 10 mmol: 10 mmol: 15-20 mmol: 60-80 mL.

[0012] In a preferred embodiment of the present invention, the ratio of the fluorinated fluorescein compound, hindered amine chloride compound, anhydrous potassium carbonate, N,N-dimethylformamide and toluene in step A3 is 10 mmol: 20 mmol: 30-40 mmol: 60-70 mL: 20-30 mL; and the mass fraction of the hydrochloric acid solution is 10-12%.

[0013] Secondly, this application provides a method for preparing thermal insulation coatings for building exterior walls, comprising the following steps: Step 1: Weigh out 25-30 parts by weight of styrene-acrylic emulsion, 5-17 parts by weight of modified composite heat insulation powder, 0.7-2.5 parts by weight of hindered amine-grafted fluorescein compound, 10-12 parts by weight of heavy calcium carbonate, 2-3 parts by weight of antifreeze, 0.8-1 parts by weight of dispersant, 0.4-0.6 parts by weight of defoamer, 0.3-0.5 parts by weight of wetting agent, 0.2-0.3 parts by weight of leveling agent, 0.7-1.1 parts by weight of thickener, 1.8-2.6 parts by weight of film-forming aid, and 30-35 parts by weight of deionized water, and set aside. Step 2: Add styrene-acrylic emulsion, modified composite heat insulation powder, hindered amine-grafted fluorescein compound, heavy calcium carbonate, antifreeze, dispersant, defoamer, wetting agent, leveling agent, thickener, film-forming aid, and deionized water to a mixer and mix for 30-60 minutes at a temperature of 20-25℃ and a stirring rate of 600-800 r / min to obtain the building exterior wall heat insulation coating.

[0014] In a preferred embodiment of the present invention, the styrene-acrylic emulsion is Dow Biomole DC-420 styrene-acrylic emulsion.

[0015] In a preferred embodiment of the present invention, the average particle size of the heavy calcium carbonate is 1000 mesh.

[0016] In a preferred embodiment of the present invention, the antifreeze is propylene glycol.

[0017] In a preferred embodiment of the present invention, the dispersant is BYK-190 dispersant.

[0018] In a preferred embodiment of the present invention, the defoamer is TEGO-810 defoamer.

[0019] In a preferred embodiment of the present invention, the wetting agent is CF-10 water-based wetting agent.

[0020] In a preferred embodiment of the present invention, the leveling agent is TEGO-450 leveling agent.

[0021] In a preferred embodiment of the present invention, the thickener is RM-8W thickener.

[0022] In a preferred embodiment of the present invention, the film-forming aid is an alcohol ester twelve film-forming aid.

[0023] Compared with the prior art, the beneficial effects of the present invention are: The present invention relates to a building exterior wall thermal insulation coating and its preparation method. The coating is prepared by mixing styrene-acrylic emulsion, modified composite thermal insulation powder, hindered amine-grafted fluorescein compound, heavy calcium carbonate, antifreeze, dispersant, defoamer, wetting agent, leveling agent, thickener, film-forming aid, and deionized water. This preparation method utilizes the rational compounding of the components to ensure good adhesion to the building exterior wall, effectively reducing heat transfer from the external environment to the building interior, thereby maintaining a comfortable internal temperature, reducing energy consumption, and achieving energy conservation and environmental protection. Simultaneously, it effectively prevents moisture penetration, avoiding coating damage and achieving long-lasting high thermal insulation performance. Furthermore, it prevents moisture penetration into the building's internal structure, protecting the building from water damage, significantly extending the building's service life, and enhancing the overall aesthetics of the building. In summary, this building exterior wall thermal insulation coating possesses excellent thermal insulation and water resistance properties. When applied to the building exterior wall, it effectively maintains the building's internal temperature comfort and prevents moisture penetration, ensuring the building's long-term safety and durability.

[0024] In the preparation of building exterior wall thermal insulation coatings, a modified composite thermal insulation powder was first prepared. The composite thermal insulation powder was modified using a silane coupling agent KH-560. The siloxane on the silane coupling agent KH-560 was hydrolyzed to form silanol, which was then grafted onto the surface of the composite thermal insulation powder, forming an organosilicon coating layer. Simultaneously, epoxy groups were introduced, resulting in the modified composite thermal insulation powder. After modification, the composite thermal insulation powder can be uniformly dispersed in the coating, and the introduced epoxy groups can enhance the adhesion of the composite thermal insulation powder in the coating, preventing it from falling off. Moreover, the hollow structure of the glass microspheres in the composite thermal insulation powder can effectively block heat conduction and scatter light. The nano-titanium dioxide and nano-zinc oxide in the composite thermal insulation powder have excellent light reflection and ultraviolet absorption properties. The combination of these three can combine the advantages of physical barrier and light regulation to form a continuous and rich thermal insulation network, achieving efficient heat blocking.

[0025] In the preparation of thermal insulation coatings for building exterior walls, a hindered amine-grafted fluorescein compound was first prepared. A spironolactone derivative of fluorescein was formed by reacting fluorescein with 3,5-bis(trifluoromethyl)benzylamine, introducing a large number of fluorescein atoms to obtain a fluorinated fluorescein compound. Then, the amino group on 2,2,6,6-tetramethylpiperidinamine reacted with the acyl chloride group on chloroacetyl chloride, simultaneously introducing chlorine atoms to obtain a chlorinated hindered amine compound. Finally, the hydroxyl group on the fluorinated fluorescein compound reacted with the chlorine atom on the chlorinated hindered amine compound to introduce hindered fluorescein atoms. A hindered amine structure was used to obtain a hindered amine-grafted fluorescein compound. The molecule of this hindered amine-grafted fluorescein compound contains both fluorescein and hindered amine structures, which endows it with excellent light absorption properties, thereby reducing heat conduction through the building's exterior walls and enhancing the thermal insulation effect. At the same time, the molecule of the hindered amine-grafted fluorescein compound contains a large number of fluorine atoms, which endows the coating with excellent chemical stability, effectively blocking the impact and erosion of rainwater, enabling the building's exterior wall thermal insulation coating to maintain a high thermal insulation effect for a long time, and ensuring the long-term safety and durability of the building. Detailed Implementation

[0026] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1: This embodiment describes a method for preparing a thermal insulation coating for building exterior walls, comprising the following steps: Step S1: Add 10g of composite heat insulation powder, 90mL of toluene, and 1.5g of silane coupling agent KH-560 to a three-necked flask equipped with a stirrer and thermometer. Stir the mixture at 20℃ and a stirring rate of 200r / min for 10min. Then, raise the temperature to 60℃ and continue stirring for 2h. After that, add 15mL of deionized water and 2mL of 10% hydrochloric acid solution and continue stirring for 4h. After the reaction is complete, cool the reaction product to room temperature. Centrifugation was performed, and the precipitate was washed three times with anhydrous ethanol. The precipitate was then placed in a vacuum drying oven and dried at 60°C for 3 hours to obtain the modified composite heat-insulating powder. The composite heat-insulating powder is a mixture of glass microspheres, nano-titanium dioxide, and nano-zinc oxide in a mass ratio of 5:1:0.5. The glass microspheres are 3M hollow glass microspheres K15; the nano-titanium dioxide is anatase nano-titanium dioxide with an average particle size of 5 nm; and the nano-zinc oxide is nano-zinc oxide with an average particle size of 30 nm. Step S2: 20 mmol of fluorescein, 25 mmol of 3,5-bis(trifluoromethyl)benzylamine and 80 mL of anhydrous ethanol were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 20 °C and 200 r / min for 10 min. Then the temperature was raised to 80 °C and the mixture was stirred for 9 h. After the reaction was completed, the reaction product was cooled to room temperature. The solvent was then removed by rotary evaporation. The product was then added to distilled water and vacuum filtered. The filter cake was placed in a vacuum drying oven and dried at 60 °C for 2 h to obtain the fluorinated fluorescein compound. Step S3: 10 mmol of 2,2,6,6-tetramethylpiperidinamine, 10 mmol of chloroacetyl chloride, 15 mmol of triethylamine and 60 mL of dichloromethane were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred at 0 °C and 200 r / min for 10 min. The temperature was then raised to 20 °C and the mixture was stirred for 2 h. The temperature was then raised to 50 °C and the mixture was stirred for 3 h. After the reaction was completed, the reaction product was cooled to room temperature, washed three times with distilled water, dried with anhydrous magnesium sulfate, and then filtered under vacuum. The solvent was removed by rotary evaporation of the filtrate to obtain the hindered amine chloride compound. Step S4: 10 mmol of fluorescein fluorescein compound, 20 mmol of hindered amine chloride compound, 30 mmol of anhydrous potassium carbonate, 60 mL of N,N-dimethylformamide and 20 mL of toluene were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 20 °C and 200 r / min for 30 min. Then the temperature was raised to 120 °C and the mixture was stirred for another 5 h. After the reaction was completed, the reaction product was cooled to room temperature and then added to distilled water. The pH was then adjusted to 6 with 10% hydrochloric acid solution. The mixture was then vacuum filtered and the filter cake was placed in a vacuum drying oven and dried at 60 °C for 3 h to obtain the hindered amine-grafted fluorescein compound. Step S5: Weigh out 25 parts by weight of styrene-acrylic emulsion, 5 parts by weight of modified composite heat insulation powder, 0.7 parts by weight of hindered amine-grafted fluorescein compound, 10 parts by weight of heavy calcium carbonate, 2 parts by weight of antifreeze, 0.8 parts by weight of dispersant, 0.4 parts by weight of defoamer, 0.3 parts by weight of wetting agent, 0.2 parts by weight of leveling agent, 0.7 parts by weight of thickener, 1.8 parts by weight of film-forming aid, and 30 parts by weight of deionized water, and set aside for later use; the styrene-acrylic emulsion is Dow Biotech DC-420 styrene-acrylic emulsion; the average particle size of the heavy calcium carbonate is 1000 mesh; the antifreeze is propylene glycol; the dispersant is BYK-190 dispersant; the defoamer is TEGO-810 defoamer; the wetting agent is CF-10 water-based wetting agent; the leveling agent is TEGO-450 leveling agent; the thickener is RM-8W thickener; and the film-forming aid is alcohol ester twelve film-forming aid. Step S6: Add styrene-acrylic emulsion, modified composite heat insulation powder, hindered amine-grafted fluorescein compound, heavy calcium carbonate, antifreeze, dispersant, defoamer, wetting agent, leveling agent, thickener, film-forming aid, and deionized water to a mixer and mix for 30 minutes at a temperature of 20°C and a stirring rate of 600 r / min to obtain the building exterior wall heat insulation coating.

[0028] Example 2: This embodiment describes a method for preparing a thermal insulation coating for building exterior walls, comprising the following steps: Step S1: Add 10g of composite heat insulation powder, 95mL of toluene, and 4g of silane coupling agent KH-560 to a three-necked flask equipped with a stirrer and thermometer. Stir the mixture at 22℃ and a stirring rate of 250r / min for 15min. Then, raise the temperature to 62℃ and continue stirring for 2.5h. After that, add 18mL of deionized water and 2.5mL of 11% hydrochloric acid solution and continue stirring for 5h. After the reaction is complete, cool the reaction product to room temperature. After centrifugation, the precipitate was washed four times with anhydrous ethanol and then placed in a vacuum drying oven and dried at 62°C for 4 hours to obtain modified composite heat insulation powder. The composite heat insulation powder is a mixture of glass microspheres, nano-titanium dioxide, and nano-zinc oxide in a mass ratio of 5:2:1. The glass microspheres are 3M hollow glass microspheres K15. The nano-titanium dioxide is anatase nano-titanium dioxide with an average particle size of 5 nm. The nano-zinc oxide is nano-zinc oxide with an average particle size of 30 nm. Step S2: 20 mmol of fluorescein, 28 mmol of 3,5-bis(trifluoromethyl)benzylamine and 90 mL of anhydrous ethanol were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 22 °C and 250 r / min for 15 min. Then the temperature was raised to 82 °C and the mixture was stirred for 9.5 h. After the reaction was completed, the reaction product was cooled to room temperature. The solvent was then removed by rotary evaporation. The product was then added to distilled water and vacuum filtered. The filter cake was placed in a vacuum drying oven and dried at 62 °C for 2.5 h to obtain the fluorinated fluorescein compound. Step S3: 10 mmol of 2,2,6,6-tetramethylpiperidinamine, 10 mmol of chloroacetyl chloride, 18 mmol of triethylamine and 70 mL of dichloromethane were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred at 2°C and 250 r / min for 15 min. The temperature was then raised to 22°C and the mixture was stirred for 2.5 h. The temperature was then raised to 52°C and the mixture was stirred for 3.5 h. After the reaction was completed, the reaction product was cooled to room temperature, washed four times with distilled water, dried with anhydrous magnesium sulfate, and then filtered under vacuum. The solvent was removed by rotary evaporation of the filtrate to obtain the hindered amine chloride compound. Step S4: 10 mmol of fluorescein fluorescein compound, 20 mmol of hindered amine compound, 35 mmol of anhydrous potassium carbonate, 65 mL of N,N-dimethylformamide and 25 mL of toluene were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 22 °C and 250 r / min for 45 min. The temperature was then raised to 125 °C and the mixture was stirred for 7 h. After the reaction was completed, the reaction product was cooled to room temperature and then added to distilled water. The pH was then adjusted to 6 with 11% hydrochloric acid solution. The mixture was then vacuum filtered and the filter cake was placed in a vacuum drying oven and dried at 62 °C for 4 h to obtain the hindered amine-grafted fluorescein compound. Step S5: Weigh out 28 parts by weight of styrene-acrylic emulsion, 11 parts by weight of modified composite heat insulation powder, 1.6 parts by weight of hindered amine-grafted fluorescein compound, 11 parts by weight of heavy calcium carbonate, 2.5 parts by weight of antifreeze, 0.9 parts by weight of dispersant, 0.5 parts by weight of defoamer, 0.4 parts by weight of wetting agent, 0.25 parts by weight of leveling agent, 0.9 parts by weight of thickener, 2.2 parts by weight of film-forming aid, and 32 parts by weight of deionized water, and set aside; the styrene-acrylic emulsion is Dow Polymer. DC-420 styrene-acrylic emulsion; the average particle size of the heavy calcium carbonate is 1000 mesh; the antifreeze is propylene glycol; the dispersant is BYK-190 dispersant; the defoamer is TEGO-810 defoamer; the wetting agent is CF-10 water-based wetting agent; the leveling agent is TEGO-450 leveling agent; the thickener is RM-8W thickener; the film-forming aid is alcohol ester twelve film-forming aid. Step S6: Add styrene-acrylic emulsion, modified composite heat insulation powder, hindered amine-grafted fluorescein compound, heavy calcium carbonate, antifreeze, dispersant, defoamer, wetting agent, leveling agent, thickener, film-forming aid, and deionized water to a mixer and mix for 45 minutes at a temperature of 22°C and a stirring rate of 700 r / min to obtain the building exterior wall heat insulation coating.

[0029] Example 3: This embodiment describes a method for preparing a thermal insulation coating for building exterior walls, comprising the following steps: Step S1: Add 10g of composite heat insulation powder, 100mL of toluene, and 7.5g of silane coupling agent KH-560 to a three-necked flask equipped with a stirrer and thermometer. Stir the mixture at 25℃ and a stirring rate of 300r / min for 20min. Then, raise the temperature to 65℃ and continue stirring for 3h. Next, add 20mL of deionized water and 3mL of 12% hydrochloric acid solution and continue stirring for 6h. After the reaction is complete, cool the reaction product to room temperature. After centrifugation, the precipitate was washed five times with anhydrous ethanol and then placed in a vacuum drying oven and dried at 65°C for 5 hours to obtain modified composite heat insulation powder. The composite heat insulation powder is a mixture of glass microspheres, nano-titanium dioxide, and nano-zinc oxide in a mass ratio of 5:3:1.5. The glass microspheres are 3M hollow glass microspheres K15. The nano-titanium dioxide is anatase nano-titanium dioxide with an average particle size of 5 nm. The nano-zinc oxide is nano-zinc oxide with an average particle size of 30 nm. Step S2: 20 mmol of fluorescein, 30 mmol of 3,5-bis(trifluoromethyl)benzylamine and 100 mL of anhydrous ethanol were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 25 °C and 300 r / min for 20 min. Then the temperature was raised to 85 °C and the mixture was stirred for 10 h. After the reaction was completed, the reaction product was cooled to room temperature. The solvent was then removed by rotary evaporation. The product was then added to distilled water and vacuum filtered. The filter cake was placed in a vacuum drying oven and dried at 65 °C for 3 h to obtain the fluorinated fluorescein compound. Step S3: 10 mmol of 2,2,6,6-tetramethylpiperidinamine, 10 mmol of chloroacetyl chloride, 20 mmol of triethylamine and 80 mL of dichloromethane were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred at 3°C ​​and 300 r / min for 20 min. The temperature was then raised to 25°C and the mixture was stirred for 3 h. The temperature was then raised to 55°C and the mixture was stirred for 4 h. After the reaction was completed, the product was cooled to room temperature, washed five times with distilled water, dried with anhydrous magnesium sulfate, and then filtered under vacuum. The solvent was removed by rotary evaporation of the filtrate to obtain the hindered amine chloride compound. Step S4: 10 mmol of fluorescein fluorescein compound, 20 mmol of hindered amine compound, 40 mmol of anhydrous potassium carbonate, 70 mL of N,N-dimethylformamide and 30 mL of toluene were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 25 °C and 300 r / min for 60 min. Then the temperature was raised to 130 °C and the mixture was stirred for 9 h. After the reaction was completed, the reaction product was cooled to room temperature and then added to distilled water. The pH was then adjusted to 6.5 with 12% hydrochloric acid solution. The mixture was then vacuum filtered and the filter cake was placed in a vacuum drying oven and dried at 65 °C for 5 h to obtain hindered amine grafted fluorescein compound. Step S5: Weigh out 30 parts by weight of styrene-acrylic emulsion, 17 parts by weight of modified composite heat insulation powder, 2.5 parts by weight of hindered amine-grafted fluorescein compound, 12 parts by weight of heavy calcium carbonate, 3 parts by weight of antifreeze, 1 part by weight of dispersant, 0.6 parts by weight of defoamer, 0.5 parts by weight of wetting agent, 0.3 parts by weight of leveling agent, 1.1 parts by weight of thickener, 2.6 parts by weight of film-forming aid, and 35 parts by weight of deionized water, and set aside for later use; the styrene-acrylic emulsion is Dow Biotech DC-420 styrene-acrylic emulsion; the average particle size of the heavy calcium carbonate is 1000 mesh; the antifreeze is propylene glycol; the dispersant is BYK-190 dispersant; the defoamer is TEGO-810 defoamer; the wetting agent is CF-10 water-based wetting agent; the leveling agent is TEGO-450 leveling agent; the thickener is RM-8W thickener; and the film-forming aid is alcohol ester twelve film-forming aid. Step S6: Add styrene-acrylic emulsion, modified composite heat insulation powder, hindered amine-grafted fluorescein compound, heavy calcium carbonate, antifreeze, dispersant, defoamer, wetting agent, leveling agent, thickener, film-forming aid, and deionized water to a mixer and mix for 60 minutes at a temperature of 25°C and a stirring rate of 800 r / min to obtain the building exterior wall heat insulation coating.

[0030] Comparative Example 1: This comparative example illustrates a method for preparing a thermal insulation coating for building exterior walls, comprising the following steps: Step S1: Weigh out 30 parts by weight of styrene-acrylic emulsion, 12 parts by weight of heavy calcium carbonate, 3 parts by weight of antifreeze, 1 part by weight of dispersant, 0.6 parts by weight of defoamer, 0.5 parts by weight of wetting agent, 0.3 parts by weight of leveling agent, 1.1 parts by weight of thickener, 2.6 parts by weight of film-forming aid, and 35 parts by weight of deionized water, and set aside for later use; the styrene-acrylic emulsion is Dow Biotech DC-420 styrene-acrylic emulsion; the average particle size of the heavy calcium carbonate is 1000 mesh; the antifreeze is propylene glycol; the dispersant is BYK-190 dispersant; the defoamer is TEGO-810 defoamer; the wetting agent is CF-10 water-based wetting agent; the leveling agent is TEGO-450 leveling agent; the thickener is RM-8W thickener; and the film-forming aid is alcohol ester twelve film-forming aid. Step S2: Add styrene-acrylic emulsion, heavy calcium carbonate, antifreeze, dispersant, defoamer, wetting agent, leveling agent, thickener, film-forming aid, and deionized water to a mixer and mix for 60 minutes at a temperature of 25°C and a stirring speed of 800 r / min to obtain the building exterior wall thermal insulation coating.

[0031] Comparative Example 2: This comparative example illustrates a method for preparing a thermal insulation coating for building exterior walls, comprising the following steps: Step S1: Add 10g of composite heat insulation powder, 100mL of toluene, and 7.5g of silane coupling agent KH-560 to a three-necked flask equipped with a stirrer and thermometer. Stir the mixture at 25℃ and a stirring rate of 300r / min for 20min. Then, raise the temperature to 65℃ and continue stirring for 3h. Next, add 20mL of deionized water and 3mL of 12% hydrochloric acid solution and continue stirring for 6h. After the reaction is complete, cool the reaction product to room temperature. After centrifugation, the precipitate was washed five times with anhydrous ethanol and then placed in a vacuum drying oven and dried at 65°C for 5 hours to obtain modified composite heat insulation powder. The composite heat insulation powder is a mixture of glass microspheres, nano-titanium dioxide, and nano-zinc oxide in a mass ratio of 5:3:1.5. The glass microspheres are 3M hollow glass microspheres K15. The nano-titanium dioxide is anatase nano-titanium dioxide with an average particle size of 5 nm. The nano-zinc oxide is nano-zinc oxide with an average particle size of 30 nm. Step S2: Weigh out 30 parts by weight of styrene-acrylic emulsion, 17 parts by weight of modified composite heat insulation powder, 12 parts by weight of heavy calcium carbonate, 3 parts by weight of antifreeze, 1 part by weight of dispersant, 0.6 parts by weight of defoamer, 0.5 parts by weight of wetting agent, 0.3 parts by weight of leveling agent, 1.1 parts by weight of thickener, 2.6 parts by weight of film-forming aid, and 35 parts by weight of deionized water for later use; the styrene-acrylic emulsion is Dow Biotech DC-420 styrene-acrylic emulsion; the average particle size of the heavy calcium carbonate is 1000 mesh; the antifreeze is propylene glycol; the dispersant is BYK-190 dispersant; the defoamer is TEGO-810 defoamer; the wetting agent is CF-10 water-based wetting agent; the leveling agent is TEGO-450 leveling agent; the thickener is RM-8W thickener; and the film-forming aid is alcohol ester twelve film-forming aid. Step S3: Add styrene-acrylic emulsion, modified composite heat insulation powder, heavy calcium carbonate, antifreeze, dispersant, defoamer, wetting agent, leveling agent, thickener, film-forming aid and deionized water into a mixer, and stir and mix for 60 minutes at a temperature of 25℃ and a stirring speed of 800r / min to obtain the building exterior wall heat insulation coating.

[0032] Comparative Example 3: This comparative example illustrates a method for preparing a thermal insulation coating for building exterior walls, comprising the following steps: Step S1: 20 mmol of fluorescein, 30 mmol of 3,5-bis(trifluoromethyl)benzylamine and 100 mL of anhydrous ethanol were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 25 °C and 300 r / min for 20 min. Then the temperature was raised to 85 °C and the mixture was stirred for 10 h. After the reaction was completed, the reaction product was cooled to room temperature. The solvent was then removed by rotary evaporation. The product was then added to distilled water and vacuum filtered. The filter cake was placed in a vacuum drying oven and dried at 65 °C for 3 h to obtain the fluorinated fluorescein compound. Step S2: 10 mmol of 2,2,6,6-tetramethylpiperidinamine, 10 mmol of chloroacetyl chloride, 20 mmol of triethylamine and 80 mL of dichloromethane were added to a three-necked flask equipped with a stirrer and a thermometer. The mixture was stirred at 3°C ​​and 300 r / min for 20 min. The temperature was then raised to 25°C and the mixture was stirred for 3 h. The temperature was then raised to 55°C and the mixture was stirred for 4 h. After the reaction was completed, the product was cooled to room temperature, washed five times with distilled water, dried with anhydrous magnesium sulfate, and then filtered under vacuum. The solvent was removed by rotary evaporation of the filtrate to obtain the hindered amine chloride compound. Step S3: 10 mmol of fluorescein fluorescein compound, 20 mmol of hindered amine compound, 40 mmol of anhydrous potassium carbonate, 70 mL of N,N-dimethylformamide and 30 mL of toluene were added to a three-necked flask equipped with a stirrer, thermometer and gas delivery tube. Nitrogen gas was introduced for protection. The mixture was stirred at 25 °C and 300 r / min for 60 min. The temperature was then raised to 130 °C and the mixture was stirred for another 9 h. After the reaction was completed, the reaction product was cooled to room temperature and then added to distilled water. The pH was then adjusted to 6.5 with 12% hydrochloric acid solution. The mixture was then vacuum filtered and the filter cake was placed in a vacuum drying oven and dried at 65 °C for 5 h to obtain the hindered amine-grafted fluorescein compound. Step S4: Weigh out 30 parts by weight of styrene-acrylic emulsion, 2.5 parts by weight of hindered amine-grafted fluorescein compound, 12 parts by weight of heavy calcium carbonate, 3 parts by weight of antifreeze, 1 part by weight of dispersant, 0.6 parts by weight of defoamer, 0.5 parts by weight of wetting agent, 0.3 parts by weight of leveling agent, 1.1 parts by weight of thickener, 2.6 parts by weight of film-forming aid, and 35 parts by weight of deionized water, and set aside. The styrene-acrylic emulsion is Dow Biotech DC-420 styrene-acrylic emulsion; the average particle size of the heavy calcium carbonate is 1000 mesh; the antifreeze is propylene glycol; the dispersant is BYK-190 dispersant; the defoamer is TEGO-810 defoamer; the wetting agent is CF-10 water-based wetting agent; the leveling agent is TEGO-450 leveling agent; the thickener is RM-8W thickener; and the film-forming aid is alcohol ester twelve film-forming aid. Step S5: Add styrene-acrylic emulsion, hindered amine-grafted fluorescein compound, heavy calcium carbonate, antifreeze, dispersant, defoamer, wetting agent, leveling agent, thickener, film-forming aid, and deionized water to a mixer and mix for 60 minutes at a temperature of 25°C and a stirring rate of 800 r / min to obtain the building exterior wall thermal insulation coating.

[0033] Comparative Example 4: This comparative example illustrates a method for preparing a thermal insulation coating for building exterior walls, comprising the following steps: Step S1: Weigh out 30 parts by weight of styrene-acrylic emulsion, 17 parts by weight of glass microspheres, 2.5 parts by weight of 3,5-bis(trifluoromethyl)aniline, 12 parts by weight of heavy calcium carbonate, 3 parts by weight of antifreeze, 1 part by weight of dispersant, 0.6 parts by weight of defoamer, 0.5 parts by weight of wetting agent, 0.3 parts by weight of leveling agent, 1.1 parts by weight of thickener, 2.6 parts by weight of film-forming aid, and 35 parts by weight of deionized water, and set aside; the styrene-acrylic emulsion is Dow Biotech DC-420 styrene-acrylic emulsion; the... The glass microspheres are 3M hollow glass microspheres K15; the average particle size of the heavy calcium carbonate is 1000 mesh; the antifreeze is propylene glycol; the dispersant is BYK-190 dispersant; the defoamer is TEGO-810 defoamer; the wetting agent is CF-10 water-based wetting agent; the leveling agent is TEGO-450 leveling agent; the thickener is RM-8W thickener; and the film-forming aid is alcohol ester twelve film-forming aid. Step S2: Add styrene-acrylic emulsion, glass microspheres, 3,5-bis(trifluoromethyl)aniline, heavy calcium carbonate, antifreeze, dispersant, defoamer, wetting agent, leveling agent, thickener, film-forming aid, and deionized water to a mixer and mix for 60 minutes at a temperature of 25°C and a stirring speed of 800 r / min to obtain the building exterior wall thermal insulation coating.

[0034] The thermal conductivity and thermal insulation temperature difference of the building exterior wall insulation coatings of Examples 1-3 and Comparative Examples 1-4 were tested according to GB / T 25261-2018 standard, and the water resistance of the coatings after immersion for 96 hours was tested according to GB / T 1733-1993 standard. The coating surface was observed for discoloration, blistering, peeling and other phenomena.

[0035]

[0036] Referring to the data in the table above, and based on the comparison between Examples 1-3 and Comparative Examples 1-4, it can be seen that the building exterior wall thermal insulation coating of this application has excellent thermal insulation performance and water resistance performance.

[0037] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0038] The above description is merely an example and illustration of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the invention or exceed the scope defined in this application, they should all fall within the protection scope of the present invention.

Claims

1. A heat-insulating coating for building exterior walls, characterized in that, Includes the following components by weight: The composition includes 25-30 parts of styrene-acrylic emulsion, 5-17 parts of modified composite heat insulation powder, 0.7-2.5 parts of hindered amine-grafted fluorescein compound, 10-12 parts of heavy calcium carbonate, 2-3 parts of antifreeze, 0.8-1 part of dispersant, 0.4-0.6 parts of defoamer, 0.3-0.5 parts of wetting agent, 0.2-0.3 parts of leveling agent, 0.7-1.1 parts of thickener, 1.8-2.6 parts of film-forming aid, and 30-35 parts of deionized water. The modified composite heat insulation powder is prepared by the following steps: The composite heat insulation powder, toluene, and silane coupling agent KH-560 were stirred and reacted. Then, deionized water and hydrochloric acid solution were added and the reaction was continued. After the reaction was completed, the reaction product was cooled, centrifuged, and the precipitate was washed and dried to obtain the modified composite heat insulation powder.

2. The building exterior wall thermal insulation coating according to claim 1, characterized in that, The ratio of the composite heat insulation powder, toluene, silane coupling agent KH-560, deionized water, and hydrochloric acid solution is 10g: 90-100mL: 1.5-7.5g: 15-20mL: 2-3mL.

3. The building exterior wall thermal insulation coating according to claim 1, characterized in that, The composite heat insulation powder is a mixture of glass microspheres, nano titanium dioxide, and nano zinc oxide in a mass ratio of 5:1-3:0.5-1.5; the hydrochloric acid solution has a mass fraction of 10-12%.

4. The building exterior wall thermal insulation coating according to claim 3, characterized in that, The glass microspheres are 3M hollow glass microspheres K15; the nano titanium dioxide is anatase nano titanium dioxide with an average particle size of 5nm; and the nano zinc oxide is nano zinc oxide with an average particle size of 30nm.

5. The building exterior wall thermal insulation coating according to claim 1, characterized in that, The hindered amine-grafted fluorescein compound was prepared by the following steps: Step A1: Fluorescein, 3,5-bis(trifluoromethyl)benzylamine and anhydrous ethanol were stirred and reacted. After the reaction was completed, the reaction product was cooled, then evaporated by rotary evaporation, then added to distilled water, then filtered under vacuum, and the filter cake was dried to obtain fluorinated fluororescein compound. Step A2: 2,2,6,6-Tetramethylpiperidinamine, chloroacetyl chloride, triethylamine and dichloromethane were stirred and reacted. After the reaction was completed, the reaction product was cooled, washed and dried, then vacuum filtered, and the filtrate was evaporated by rotary evaporation to obtain the hindered amine chloride compound. Step A3: Fluorinated fluorescein compound, hindered amine compound, anhydrous potassium carbonate, N,N-dimethylformamide and toluene are stirred and reacted. After the reaction is completed, the reaction product is cooled and then added to distilled water. The pH is then adjusted with hydrochloric acid solution, followed by vacuum filtration. The filter cake is dried to obtain hindered amine-grafted fluorescein compound.

6. The building exterior wall thermal insulation coating according to claim 5, characterized in that, The ratio of fluorescein, 3,5-bis(trifluoromethyl)benzylamine, and anhydrous ethanol in step A1 is 20 mmol: 25-30 mmol: 80-100 mL.

7. The building exterior wall thermal insulation coating according to claim 5, characterized in that, The ratio of 2,2,6,6-tetramethylpiperidine, chloroacetyl chloride, triethylamine, and dichloromethane in step A2 is 10 mmol: 10 mmol: 15-20 mmol: 60-80 mL.

8. The building exterior wall thermal insulation coating according to claim 5, characterized in that, In step A3, the ratio of the fluorinated fluorescein compound, the hindered amine compound, the anhydrous potassium carbonate, N,N-dimethylformamide, and toluene is 10 mmol: 20 mmol: 30-40 mmol: 60-70 mL: 20-30 mL; and the mass fraction of the hydrochloric acid solution is 10-12%.

9. The method for preparing the thermal insulation coating for building exterior walls according to any one of claims 1-8, characterized in that, Includes the following steps: Step 1: Weigh out 25-30 parts by weight of styrene-acrylic emulsion, 5-17 parts by weight of modified composite heat insulation powder, 0.7-2.5 parts by weight of hindered amine-grafted fluorescein compound, 10-12 parts by weight of heavy calcium carbonate, 2-3 parts by weight of antifreeze, 0.8-1 parts by weight of dispersant, 0.4-0.6 parts by weight of defoamer, 0.3-0.5 parts by weight of wetting agent, 0.2-0.3 parts by weight of leveling agent, 0.7-1.1 parts by weight of thickener, 1.8-2.6 parts by weight of film-forming aid, and 30-35 parts by weight of deionized water, and set aside. Step 2: Add styrene-acrylic emulsion, modified composite heat insulation powder, hindered amine-grafted fluorescein compound, heavy calcium carbonate, antifreeze, dispersant, defoamer, wetting agent, leveling agent, thickener, film-forming aid, and deionized water to a mixer and mix for 30-60 minutes at a temperature of 20-25℃ and a stirring rate of 600-800 r / min to obtain the building exterior wall heat insulation coating.

10. The method for preparing the thermal insulation coating for building exterior walls according to claim 9, characterized in that, The styrene-acrylic emulsion is Dow Biomole DC-420 styrene-acrylic emulsion; The average particle size of the heavy calcium carbonate is 1000 mesh. The antifreeze is propylene glycol; The dispersant is BYK-190 dispersant; The defoamer is TEGO-810 defoamer; The wetting agent is CF-10 water-based wetting agent; The leveling agent is TEGO-450 leveling agent; The thickener is RM-8W thickener; The film-forming aid is an alcohol ester twelve film-forming aid.

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