Reflective heat-insulating and heat-preserving aerogel paint and preparation method thereof

Abstract

The application provides a reflective heat-insulating and heat-preserving aerogel thermal insulation finish paint, which comprises the following components: modified acrylic resin, organic silicon-coated titanium white powder, organic silicon-coated heavy calcium powder, near-infrared reflective heat-insulating titanium white powder, silica aerogel paste, additives and deionized water; wherein the modified acrylic resin is obtained by reaction of benzyl acrylate emulsion, light reflection polymer, organic silicon hydrophobic additive and ultraviolet absorber; and the light reflection polymer is titanium dioxide grafted acrylic acid. The application solves the problems of the lack of heat-preserving performance, the general weather resistance and the poor stain resistance of the existing products, and truly achieves the comprehensive protection function of reflective heat insulation, heat preservation, weather resistance and stain resistance, and has a good application prospect.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of paint technology, and mainly relates to an aerogel thermal insulation finish with the functions of heat reflection and heat preservation and a preparation method thereof. BACKGROUND

[0002] With the rapid development of the building industry in China and the increasingly prominent energy crisis, energy saving and consumption reduction of buildings are becoming more and more important. The energy consumption of heating and air conditioning accounts for 55% of the total building energy consumption in China, and is increasing at a rate of 1% per year. Therefore, research and development of building thermal insulation coatings, increasing the indoor and outdoor temperature difference, reducing cooling energy consumption in summer and reducing heating energy consumption in winter, have great economic, environmental and social benefits.

[0003] According to different thermal insulation mechanisms, the earliest thermal insulation coatings on the market are divided into three categories: barrier type thermal insulation coatings, reflective type thermal insulation coatings and radiant type thermal insulation coatings. Later, a variety of composite thermal insulation coatings with different thermal insulation mechanisms were developed. Although the thermal insulation effect of the composite thermal insulation coatings is better than that of single type thermal insulation coatings, the composite thermal insulation coatings still have the following problems: when the addition amount of thermal insulation aggregates with different thermal insulation mechanisms is small, the fillers are easy to form islands in the coatings, and heat will bypass these islands and transfer to the substrate, resulting in poor thermal insulation effect of the coatings; when the addition amount of thermal insulation aggregates with different thermal insulation mechanisms is large, the thermal insulation aggregates are unevenly distributed, affecting the thermal insulation effect, and also causing unstable paint film and short service life. In addition, the drying period of the coatings is long, the construction is easily affected by the weather environment, the overall thermal insulation and reflection performance of the coatings is not good, and in particular, the hollow ceramic microspheres have low closed porosity, high water absorption and are easy to break, which seriously affects the thermal insulation effect of the hollow ceramic microspheres and their products.

[0004] In existing products, reflective thermal insulation coatings have single function, only have the function of reflecting heat, and have no heat preservation effect, and cannot solve the problem of heat preservation in winter in hot summer and cold winter areas. At the same time, the durability of the coating film is poor, which greatly shortens the service life of the coating film, and the coating film needs to be renovated from time to time to ensure that its heat reflection and insulation performance is not affected, which undoubtedly increases the cost of investment. The outer wall coating film is easily contaminated, and the paint film has poor stain resistance. After contamination, the reflection of sunlight and near-infrared light is greatly reduced, affecting the heat reflection and insulation performance.

[0005] Therefore, it is urgent to develop a building thermal insulation and preservation coating using a building thermal insulation and preservation material different from existing thermal insulation and preservation materials to solve the problems of poor stain resistance and weather resistance of existing thermal insulation and preservation coatings, and only having the function of reflecting heat without the function of heat preservation. SUMMARY

[0006] The present application provides a kind of double effect of reflecting heat insulation and heat preservation of aerogel heat insulation finish and preparation method thereof, can well solve the problems of lacking heat preservation performance, general weather resistance and poor stain resistance of existing products, and truly reach the comprehensive protection function of reflecting heat insulation, heat preservation, weather resistance, stain resistance.

[0007] One purpose of the present application is to provide a kind of double effect of reflecting heat insulation and heat preservation of aerogel heat insulation finish, the double effect of reflecting heat insulation and heat preservation of aerogel heat insulation finish, including the following mass fraction components:

[0008]

[0009] Wherein, the modified acrylic resin is benzene propylene emulsion, light reflection polymer, organic silicon hydrophobic adjuvant, ultraviolet absorber reaction obtained;

[0010] The light reflection polymer is titanium dioxide grafted acrylic acid.

[0011] Further, the organic silicon hydrophobic adjuvant is selected from vinyl triethoxysilane.

[0012] Further, the ultraviolet absorber is selected from 2-cyano-3,3-diphenyl acrylate isooctyl ester.

[0013] Further, the adjuvant is selected from one or more of antifreeze, wetting agent, bactericide, film forming adjuvant, thickening agent, defoaming agent.

[0014] Further, the film forming adjuvant is organic silicon film forming adjuvant.

[0015] Further, the particle size of the near-infrared reflective heat insulation titanium dioxide is 600-800nm.

[0016] Further, the near-infrared reflective heat insulation titanium dioxide is selected from pan 550.

[0017] The structure of the near-infrared reflective heat insulation titanium dioxide of the present application comprises a core, a shell layer and an outer layer, wherein the core is a huge titanium dioxide treated by sulfuric acid method, has the optimal size of maximum sunlight and near-infrared reflection, can reflect sunlight to the maximum extent, and avoids the temperature rise caused by excessive heat concentration; the shell layer is dense silicon dioxide, can not only reduce the escape of free radicals, but also protect organic pigments and reduce the degradation of resin in the system by weakening ultraviolet light; and the outer layer is an alumina coating layer, so that the titanium dioxide has excellent dispersibility, is uniformly distributed in the system, and stably plays a role. When the addition amount in the formula system is 8-10%, the coating system has very high sunlight reflectivity (its lightening power is about 50% of that of traditional titanium dioxide) and excellent reflective heat insulation performance when used in medium color and light color (L>40), and the special structure of the coating system can also play a synergistic effect with the ultraviolet absorber in the modified acrylic resin, optimize the weather resistance of the system, and greatly improve the weather resistance of the coating system.

[0018] The paste-like body of the silica aerogel of the present application has the following effects: a, coated in the modified acrylic resin with high crosslinking density, interacts with the modified acrylic resin through intermolecular hydrogen bonds, forms a high hydrophobic surface, and improves the stain resistance of the paint film; b, the ordered pore structure forms nearly "infinite heat radiation reflection interfaces", effectively blocks heat radiation, and gives the system excellent heat preservation and insulation performance; c, the special mesoporous structure has high specific surface area, high porosity, small pore size and ordered pore structure, and its principle is that the pore size is smaller than the free path (70 nm) of gas molecule collision, so the gas molecules participating in heat transfer cannot pass through, thereby essentially cutting off the heat conduction of gas molecules; due to the existence of infinite mesopores, heat flow can only transfer along the pore walls when transferring in the solid, and the "infinite long path" effect formed by nearly infinite pore walls greatly reduces the heat conduction capacity of the solid; at the same time, the small pore size makes the air molecules lose the ability to flow freely and thus cannot participate in heat convection; the ordered pore structure forms nearly "infinite heat radiation reflection interfaces", effectively blocks heat radiation, gives the system excellent heat preservation and insulation performance, effectively maintains the stability of indoor wall temperature, and greatly saves energy consumption.

[0019] Another object of the present application is to provide a preparation method of the reflective heat insulation and heat preservation dual-effect aerogel thermal insulation finish paint, and the preparation method comprises the following steps:

[0020] S1, blending silicate and organosiloxane, adjusting pH, adding ammonia water dropwise and aging, adding organosilicon for hydrophobic modification, purifying to obtain hydrophobic silica aerogel, and adding a dispersing agent to obtain the paste-like body of the silica aerogel;

[0021] S2, titanium dioxide is added to an alkali solution, heated and reacted to obtain hydroxylated titanium dioxide, the hydroxylated titanium dioxide is put into acrylic acid, ultrasonic and heated to react to obtain titanium dioxide grafted acrylic acid, phenylpropyl emulsion, silicone hydrophobic aid, ultraviolet absorber are added, heated and stirred to react to obtain the modified acrylic resin;

[0022] S3, titanium dioxide, film forming aid, silicone surface treatment agent are blended, purified and ground to obtain the silicone coated titanium dioxide;

[0023] S4, barium powder, film forming aid, silicone surface treatment agent are blended, purified and ground to obtain the silicone coated barium powder;

[0024] S5, according to the above mass fraction, the silica aerogel paste, the modified acrylic resin, the silicone coated titanium dioxide, the silicone coated barium powder and other components are blended and stirred to obtain the aerogel thermal insulation paint with the functions of reflecting, heat insulation and thermal insulation.

[0025] Further, in step S1, the mass ratio of the silicate, organosiloxane and organosilicon is (1-2):(2-4):(0.6-3).

[0026] Further, in step S2, the mass ratio of the titanium dioxide grafted acrylic acid, phenylpropyl emulsion, silicone hydrophobic aid and ultraviolet absorber is (3-5):(25-35):(0.5-3):(0.5-2).

[0027] Further, in step S3, the mass ratio of the titanium dioxide, film forming aid and silicone surface treatment agent is (5-70):(1-8):(1-15).

[0028] Further, in step S4, the mass ratio of the barium powder, film forming aid and silicone surface treatment agent is (5-70):(1-8):(1-15).

[0029] The present application has the following advantages:

[0030] The modified acrylic resin of the present application is used as a base resin, which is polymerized from titanium dioxide grafted acrylic acid, phenylpropyl emulsion, silicone hydrophobic aid and ultraviolet absorber, and introduces groups such as silicone, reflective polymer and ultraviolet absorber, thereby increasing the affinity to the silicone coated titanium dioxide and barium powder, effectively adsorbing and combining the inorganic components, and the introduction of titanium dioxide grafted acrylic acid as a light reflecting polymer and ultraviolet absorber group enhances the reflection of sunlight by the coating, and the silicone hydrophobic aid endows the coating with excellent hydrophobicity, weather resistance and scrub resistance.

[0031] The present application also carries out organic silicon coating treatment on titanium dioxide and heavy calcium powder, thereby improving the compatibility between components in the coating with high inorganic filler content, avoiding the phenomenon of aggregation and uneven dispersion of reflective and heat insulation fillers, being able to further combine with the resin containing the organic silicon group, adsorbing and cross-linking through intermolecular forces, and simultaneously improving the hydrophobic effect of the product, enhancing the stability of the coating and other performances. In addition, the present application also uses the organic silicon film forming additive as a component, which can combine with the organic silicon coated titanium dioxide, the organic silicon coated heavy calcium powder and the modified acrylic resin to form a synergistic effect, thereby enhancing the film forming effect of the coating and various performances such as weather resistance, stability and strength of the product.

[0032] The reflective, heat insulation and thermal insulation double-effect aerogel heat insulation finish paint prepared by the present application has no abnormality in the xeon lamp aging test for 1500h, and the weather resistance performance is ΔE*≤0.5, which has excellent weather resistance performance; secondly, according to the GB / T 9755-2014 standard test, the stain resistance performance can reach within 10%, which is much higher than the standard requirement of 15%, and has good stain resistance performance; and compared with the reflective and heat insulation finish paint on the market, the present technical solution has the reflective and heat insulation performance and also has the thermal insulation function, which provides stronger'stability clothes' for the inside and outside of the building, effectively saves energy consumption and achieves the purpose of energy saving and emission reduction. DETAILED DESCRIPTION

[0033] In order to more clearly illustrate the technical solutions of the present application, the following examples are listed. The raw materials, reactions and post-treatment means appearing in the examples are all common raw materials on the market and technical means familiar to those skilled in the art, unless otherwise stated.

[0034] The words "preferred", "preferably", "more preferred" and the like in the present application mean the embodiments of the present application which can provide certain beneficial effects in certain cases. However, other embodiments can also be preferred in the same or other cases. In addition, the description of one or more preferred embodiments does not imply that other embodiments are not available, nor is it intended to exclude other embodiments from the scope of the present application.

[0035] It should be understood that, except in any operating examples, or otherwise indicated, expressions of amount or all numbers expressing quantities of ingredients, properties such as physical properties used in the specification and claims should be understood as being modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that can vary depending on the desired properties sought to be obtained in accordance with the present application.

[0036] The following raw materials are used in the embodiments of the present application:

[0037] 550, near-infrared reflective heat-insulating titanium white powder, purchased from Shanghai Aolun Chemical Co., Ltd.;

[0038] MBS5050, preservative, purchased from the Tol Chemical Group;

[0039] Propylene glycol, antifreeze agent, purchased from Shanghai Shengyue International Trade Co., Ltd.;

[0040] HTK-5040, sodium salt dispersant, purchased from Shanghai Hongtu Industry Co., Ltd.;

[0041] Cetyltrimethylammonium bromide, ammonium salt dispersant, purchased from Condies Chemical Industry (Hubei) Co., Ltd.;

[0042] RS-998A, styrene-acrylate emulsion, purchased from the Bafu Group Co., Ltd.;

[0043] PMX-200, silicone film-forming aid, purchased from the Dow Corning Co., Ltd.;

[0044] 2410AC, defoaming agent, purchased from the BASF Chemical Co., Ltd.;

[0045] Titanium white powder, particle size 0.2-0.3 μm;

[0046] Heavy calcium powder, particle size 10-20 μm;

[0047] RM-8W, thickening agent, purchased from the Dow Chemical Co.

[0048] Example 1

[0049] A reflective heat-insulating and heat-preserving aerogel thermal paint with double effects includes the following components in mass fraction:

[0050]

[0051] A preparation method of the reflective heat-insulating and heat-preserving aerogel thermal paint with double effects includes the following steps:

[0052] S1, 20.8 g of tetraethyl orthosilicate, 40.8 g of methyltrimethoxysilane, 23 g of anhydrous ethanol, 126 g of water were blended and stirred, 10 ml of hydrochloric acid was added and stirred for 1 h to adjust the pH, 20 ml of ammonia water, 2 ml of N,N-dimethylformamide was added, stirred for 10 min, and placed for 2 h to form a wet gel, and placed in a vacuum drying oven for aging, after aging, the wet gel was added to 100 g of an ethanol solution of hexamethyldisilazane (mass ratio of hexamethyldisilazane to ethanol was 1:4), soaked for 24 h for hydrophobic modification, and replaced with n-hexane for 24 h, the solution replacement was repeated 3 times, and the wet gel was placed in a 50℃ drying oven for normal pressure drying to obtain a hydrophobic silica aerogel, the hydrophobic silica aerogel, HTK-5040, cetyltrimethylammonium bromide, and deionized water were mixed and stirred at a mass ratio of 30:1:3:150 to obtain the silica aerogel paste.

[0053] S2, 5 g of titanium dioxide was added to 40 ml of potassium hydroxide aqueous solution with a pH value of 13 and stirred, heated to 200℃ and reacted for 30 h, filtered, washed, and dried at 60℃ to obtain hydroxylated titanium dioxide;

[0054] The hydroxylated titanium dioxide and acrylic acid were blended at a molar ratio of 1:5, a catalyst 4-dimethylaminopyridine (4-dimethylaminopyridine was used in an amount of 1% of the total mass of the hydroxylated titanium dioxide and acrylic acid) was added, ultrasonic and heated to 80℃ and reacted for 4 h, filtered and dried to obtain titanium dioxide grafted with acrylic acid;

[0055] The RS-998A, titanium dioxide grafted with acrylic acid, vinyltriethoxysilane, 2-cyano-3,3-diphenyl isooctyl acrylate, and BPO were blended with water as a solvent at a mass ratio of 29:3:3:0.5:0.3, heated to 80℃ and stirred under a nitrogen atmosphere for 3 h to obtain the modified acrylic resin.

[0056] S3, 3 g of vinyl carbonate and 100 g of deionized water were blended to obtain a solution, 30 g of titanium dioxide was added and stirred, 100 ml of 3 wt% sodium methylsilicate aqueous solution was added, stirred for 3 h, suction filtered, and placed in an oven for drying at 50℃ for 1 h and at 100℃ for 5 h, and ground and crushed to obtain the silicone-coated titanium dioxide.

[0057] S4, 3 g of vinyl carbonate and 100 g of deionized water were blended to obtain a solution, 30 g of heavy calcium carbonate was added and stirred, 100 ml of 3 wt% sodium methylsilicate aqueous solution was added, stirred for 3 h, suction filtered, and placed in an oven for drying at 50℃ for 1 h and at 100℃ for 5 h, and ground and crushed to obtain the silicone-coated heavy calcium carbonate.

[0058] S5, according to the above mass fraction, 19 parts of deionized water is added to the dispersion kettle, the rotation speed of the dispersion machine is adjusted to 1000 r / min, and then 0.5 parts of RM-8W and 5 parts of deionized water are added and stirred to obtain a reflective, heat-insulating and heat-preserving double-effect aerogel thermal insulation finish. 550, the silicone-coated titanium dioxide, the silicone-coated heavy calcium powder, and the silica aerogel paste are dispersed for 15 min, the rotation speed is reduced to 600 r / min, 0.1 parts of MBS5050, 0.3 parts of propylene glycol, modified acrylic resin, 1.2 parts of PMX-200 and 0.5 parts of 2410AC are sequentially added, and stirring is continued for 5 min; 0.5 parts of RM-8W and 5 parts of deionized water are added and stirred to obtain a reflective, heat-insulating and heat-preserving double-effect aerogel thermal insulation finish.

[0059] Example 2

[0060] A reflective, heat-insulating and heat-preserving double-effect aerogel thermal insulation finish, comprising the following components in mass fraction:

[0061]

[0062] The preparation method of the reflective, heat-insulating and heat-preserving double-effect aerogel thermal insulation finish, comprising the following steps:

[0063] S1, 20.8g of tetraethyl orthosilicate, 40.8g of methyltrimethoxysilane, 23g of anhydrous ethanol, 126g of water are blended and stirred, 10ml of hydrochloric acid is added and stirred for 1h to adjust the pH, 20ml of ammonia water and 2ml of N,N-dimethylformamide are added and stirred for 10min, and then the wet gel is formed after standing for 2h, and then the wet gel is placed in a vacuum drying oven for aging, after the aging is completed, the wet gel is added into 100g of an ethanol solution of hexamethyldisilazane (the mass ratio of hexamethyldisilazane to ethanol is 1:4), soaked for 24h for hydrophobic modification, and then solution replacement is performed with n-hexane for 24h, the solution replacement is repeated for 3 times, and then the wet gel is placed in a 50℃ drying oven for normal pressure drying to obtain a hydrophobic silica aerogel, and then the hydrophobic silica aerogel, HTK-5040, cetyltrimethylammonium bromide and deionized water are mixed and stirred at a mass ratio of 30:1:3:150 to obtain the silica aerogel paste.

[0064] S2, 5g of titanium dioxide is added into 40ml of potassium hydroxide aqueous solution with a pH value of 13 and stirred, heated to 200℃ and reacted for 30h, filtered, washed and dried at 60℃ to obtain hydroxylated titanium dioxide;

[0065] The hydroxylated titanium dioxide and acrylic acid are blended at a molar ratio of 1:5, a catalyst 4-dimethylaminopyridine (the amount of 4-dimethylaminopyridine is 1% of the total mass of the hydroxylated titanium dioxide and acrylic acid) is added, ultrasonic and heated to 80℃ and reacted for 4h, filtered and dried to obtain titanium dioxide grafted with acrylic acid;

[0066] RS-998A, titanium dioxide grafted acrylic acid, vinyl triethoxysilane, 2-cyano-3,3-diphenyl acrylate isooctyl ester, BPO were blended in water as solvent in a mass ratio of 29:3:3:0.5:0.3, heated to 80℃ under nitrogen atmosphere and stirred for 3h to obtain the modified acrylic resin.

[0067] S3, 3g of ethylene carbonate, 100g of deionized water were blended to obtain a solution, 30g of titanium dioxide was added and stirred, 100ml of 3wt% sodium methylsilicate aqueous solution was added, stirred for 3h, suction filtered, placed in an oven and dried at 50℃ for 1h and at 100℃ for 5h, ground and crushed to obtain the silicone coated titanium dioxide.

[0068] S4, 3g of ethylene carbonate, 100g of deionized water were blended to obtain a solution, 30g of heavy calcium carbonate powder was added and stirred, 100ml of 3wt% sodium methylsilicate aqueous solution was added, stirred for 3h, suction filtered, placed in an oven and dried at 50℃ for 1h and at 100℃ for 5h, ground and crushed to obtain the silicone coated heavy calcium carbonate powder.

[0069] S5, according to the above mass fraction, 20 parts of deionized water was added to a dispersion kettle, the rotation speed of the dispersion machine was adjusted to 1200r / min, 0.2 parts of MBS5050, 0.4 parts of propylene glycol, modified acrylic resin, 1.3 parts of PMX-200 and 0.6 parts of 2410AC were added in sequence, and the stirring was continued for 6min. 550, the silicone coated titanium dioxide, the silicone coated heavy calcium carbonate powder, and the silica aerogel paste were dispersed for 17min, the rotation speed was reduced to 700r / min, 0.2 parts of MBS5050, 0.4 parts of propylene glycol, modified acrylic resin, 1.3 parts of PMX-200 and 0.6 parts of 2410AC were added in sequence, and the stirring was continued for 6min; 0.6 parts of RM-8W and 8 parts of deionized water were added, and the reflective and thermal insulation dual-effect aerogel thermal insulation finish was obtained by stirring.

[0070] Example 3

[0071] A reflective and thermal insulation dual-effect aerogel thermal insulation finish, comprising the following components in mass fraction:

[0072]

[0073] The preparation method of the reflective and thermal insulation dual-effect aerogel thermal insulation finish, comprising the following steps:

[0074] S1, 20.8 g of tetraethyl orthosilicate, 40.8 g of methyltrimethoxysilane, 23 g of anhydrous ethanol, 126 g of water were blended and stirred, 10 ml of hydrochloric acid was added and stirred for 1 h to adjust the pH, 20 ml of ammonia water and 2 ml of N,N-dimethylformamide were added and stirred for 10 min, and then left to stand for 2 h to form a wet gel. The wet gel was placed in a vacuum drying oven for aging. After the aging was completed, the wet gel was added to 100 g of an ethanol solution of hexamethyldisilazane (mass ratio of hexamethyldisilazane to ethanol was 1:4), soaked for 24 h for hydrophobic modification, and then subjected to solution replacement with n-hexane for 24 h. The solution replacement was repeated three times. The wet gel was placed in a 50℃ drying oven for drying under normal pressure to obtain a hydrophobic silica aerogel. The hydrophobic silica aerogel, HTK-5040, cetyltrimethylammonium bromide and deionized water were mixed and stirred at a mass ratio of 30:1:3:150 to obtain the silica aerogel paste.

[0075] S2, 5 g of titanium dioxide was added to 40 ml of a potassium hydroxide aqueous solution with a pH value of 13 and stirred, heated to 200℃ and reacted for 30 h, filtered, washed and dried at 60℃ to obtain hydroxylated titanium dioxide;

[0076] The hydroxylated titanium dioxide and acrylic acid were blended at a molar ratio of 1:5, a catalyst 4-dimethylaminopyridine (4-dimethylaminopyridine was used in an amount of 1% of the total mass of the hydroxylated titanium dioxide and acrylic acid) was added, and then ultrasonic treatment and heating to 80℃ were performed for 4 h to obtain titanium dioxide grafted with acrylic acid.

[0077] The RS-998A, titanium dioxide grafted with acrylic acid, vinyltriethoxysilane, 2-cyano-3,3-diphenyl isooctyl acrylate and BPO were blended in water as a solvent at a mass ratio of 29:3:3:0.5:0.3, heated to 80℃ under a nitrogen atmosphere and stirred for 3 h to obtain the modified acrylic resin.

[0078] S3, 3 g of vinyl carbonate and 100 g of deionized water were blended to obtain a solution, 30 g of titanium dioxide was added and stirred, 100 ml of a 3 wt% sodium methylsilicate aqueous solution was added and stirred for 3 h, suction filtration was performed, and then the obtained product was placed in an oven and dried at 50℃ for 1 h and at 100℃ for 5 h to obtain the organosilicon-coated titanium dioxide.

[0079] S4, 3 g of vinyl carbonate and 100 g of deionized water were blended to obtain a solution, 30 g of heavy calcium carbonate was added and stirred, 100 ml of a 3 wt% sodium methylsilicate aqueous solution was added and stirred for 3 h, suction filtration was performed, and then the obtained product was placed in an oven and dried at 50℃ for 1 h and at 100℃ for 5 h to obtain the organosilicon-coated heavy calcium carbonate.

[0080] S5. According to the above-mentioned mass proportions, add 21 parts of deionized water to the dispersion vessel, adjust the disperser speed to 1500 r / min, and add... 550, silicone-coated titanium dioxide, silicone-coated heavy calcium carbonate powder, and silica aerogel paste were dispersed for 20 minutes. The rotation speed was reduced to 800 r / min. 0.3 parts MBS5050, 0.5 parts propylene glycol, modified acrylic resin, 1.4 parts PMX-200, and 0.7 parts 2410AC were added sequentially, and the mixture was stirred continuously for 7 minutes. 0.7 parts RM-8W and 10 parts deionized water were added, and the mixture was stirred to obtain an aerogel thermal insulation topcoat that combines reflective heat insulation and thermal insulation.

[0081] Comparative Example 1

[0082] The difference between Comparative Example 1 and Example 1 is that step S2 is replaced by blending RS-998A, titanium dioxide-grafted acrylic acid, and 2-cyano-3,3-diphenylacrylate isooctyl ester in a mass ratio of 29:3:0.5 to obtain the modified acrylic resin.

[0083] Comparative Example 2

[0084] The difference between Comparative Example 2 and Example 1 is that the mass of organosilicon-coated titanium dioxide and organosilicon-coated heavy calcium carbonate powder is replaced with unmodified titanium dioxide and unmodified heavy calcium carbonate powder.

[0085] Comparative Example 3

[0086] The difference between Comparative Example 3 and Example 1 is that the organosilicon film-forming aid was replaced by an equal mass of alcohol ester twelve.

[0087] Test case

[0088] Test Examples 1-3 and Comparative Examples 1-3: water permeability, scrub resistance, stain resistance, solar reflectance, near-infrared reflectance, hemispherical emissivity, aging resistance, and reflective heat insulation performance of the paint film.

[0089] Test methods

[0090] The water permeability of the paint film is tested according to Appendix B in the national standard GB / T 9755-2014 Synthetic resin exterior wall emulsion, the washability of the paint film is tested according to Appendix C in the national standard GB / T 9755-2014 Synthetic resin exterior wall emulsion, the stain resistance of the paint film is tested according to 5.17 in the national standard GB / T 9755-2014 Synthetic resin exterior wall emulsion, the solar reflectance of the paint film is tested according to Appendix A in the standard JG / T 235-2014 Architectural reflective thermal insulation coatings, the near-infrared reflectance of the paint film is tested according to Appendix B in the standard JG / T 235-2014 Architectural reflective thermal insulation coatings, the hemispherical emissivity of the paint film is tested according to Appendix C in the standard JG / T 235-2014 Architectural reflective thermal insulation coatings, the aging resistance of the paint film is tested according to 5.16 in the national standard GB / T 9755-2014 Synthetic resin exterior wall emulsion, and the reflective thermal insulation performance of the paint film is tested by detecting the temperature difference between the blank sample and the surface of the test sample away from the heat source according to the national standard JGT 235-2008 Architectural reflective thermal insulation coatings.

[0091] wherein the smaller the water permeability value, the better the waterproof performance of the paint film; the more the times of washability, the better the washability of the paint film; the smaller the stain resistance value, the better the stain resistance of the paint film; the higher the solar reflectance, the near-infrared reflectance and the hemispherical emissivity, the better the reflective thermal insulation performance of the paint film; and the larger the ΔE*, the more serious the discoloration in the aging resistance.

[0092] Table 1 shows the test results.

[0093] Table 1 shows the test results.

[0094]

[0095]

[0096] As can be seen from Table 1, the performances of Examples 1-3 are all better than those of Comparative Examples 1-3 and market products.

[0097] The performances of Examples 1-3 are better than those of Comparative Example 1 because the titanium dioxide, the acrylic emulsion and the ultraviolet absorber in Comparative Example 1 are merely physically blended, and no organic silicon hydrophobic additive is added, so that the compatibility of the modified acrylic resin with the remaining inorganic components is poor, and the modified acrylic resin is difficult to be uniformly dispersed, thereby reducing the performances.

[0098] The performances of Examples 1-3 are better than those of Comparative Example 2 because Comparative Example 2 does not modify titanium dioxide and heavy calcium carbonate, which reduces the compatibility of high content inorganic components with the remaining components, cannot crosslink with organic components, and is more likely to agglomerate, which reduces performance.

[0099] The performances of Examples 1-3 are slightly better than those of Comparative Example 3 because Comparative Example 3 replaces silicone film-forming additives with alcohol ester twelve, which is less compatible with the high content of silicone groups in the components than silicone film-forming additives, so alcohol ester twelve is not easily uniformly dispersed, the film-forming effect is poor, and finally adversely affects the performance of the product.

[0100] It is apparent for those skilled in the art that the present application is not limited to the details of the foregoing exemplary embodiments, and thus can be implemented in other particular forms without departing from the spirit or essential characteristics of the present application. The foregoing embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the present application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

[0101] Furthermore, it should be understood that although the present specification is described in terms of embodiments, not every embodiment exhibits every characteristic or exhibits the described implementation to the same extent. The description is therefore to be seen as a whole with the understanding that each embodiment and every detail thereof can refer to one or more of the other embodiments and / or details.

Claims

1. An aerogel thermal insulation topcoat that combines reflective heat insulation and thermal insulation effects, characterized in that, The aerogel thermal insulation topcoat, which combines reflective heat insulation and thermal insulation, comprises the following components in parts by weight: 25-35 parts modified acrylic resin 12-14 parts of silicone-coated titanium dioxide 13-15 parts of silicone-coated heavy calcium carbonate powder 8-10 parts of near-infrared reflective heat-insulating titanium dioxide 4-6 parts of silica aerogel paste 2.6-4 parts of additives 14-16 parts deionized water; The modified acrylic resin is obtained by reacting styrene-acrylic emulsion, light-reflecting polymer, organosilicon hydrophobic additive, and ultraviolet absorber. The light-reflecting polymer is titanium dioxide grafted with acrylic acid; The organosilicon hydrophobic additive is selected from vinyltriethoxysilane; The ultraviolet absorber is selected from 2-cyano-3,3-diphenylacrylate isooctyl ester.

2. The aerogel thermal insulation topcoat with both reflective and heat-insulating effects as described in claim 1, characterized in that, The additives are selected from one or more of the following: antifreeze, wetting agent, bactericide, film-forming aid, thickener, and defoamer.

3. The aerogel thermal insulation topcoat with both reflective and heat-insulating effects as described in claim 2, characterized in that, The film-forming aid is an organosilicon film-forming aid.

4. The preparation method of the aerogel thermal insulation topcoat with both reflective heat insulation and thermal insulation effects as described in any one of claims 1-3, characterized in that, The preparation method of the aerogel heat-insulating topcoat that combines reflective heat insulation and thermal insulation includes the following steps: S1. Blend silicate ester and organosiloxane, adjust pH, add ammonia and age, add organosilicon for hydrophobic modification, purify to obtain hydrophobic silica aerogel, add dispersant to obtain silica aerogel paste; S2. Add titanium dioxide to an alkaline solution and heat to react, to obtain hydroxylated titanium dioxide. Place the hydroxylated titanium dioxide into acrylic acid, sonicate and heat to react, to obtain titanium dioxide grafted with acrylic acid. Add styrene-acrylic emulsion, organosilicon hydrophobic additive, and ultraviolet absorber, heat and stir, and react to obtain the modified acrylic resin. S3. Titanium dioxide, film-forming aid, and organosilicon surface treatment agent are mixed, purified, and ground to obtain the organosilicon-coated titanium dioxide. S4. Mix the heavy calcium carbonate powder, film-forming aid, and organosilicon surface treatment agent, purify, and grind to obtain the organosilicon-coated heavy calcium carbonate powder. S5. According to the above-mentioned mass proportions, the silica aerogel paste, modified acrylic resin, organosilicon-coated titanium dioxide, organosilicon-coated heavy calcium carbonate powder and other components are mixed and stirred to obtain an aerogel heat insulation topcoat that combines reflective heat insulation and thermal insulation.

5. The preparation method of the aerogel thermal insulation topcoat with both reflective heat insulation and thermal insulation effects according to claim 4, characterized in that, In step S1, the mass ratio of the silicate ester, organosiloxane, and organosilicon is (1-2):(2-4):(0.6-3).

6. The preparation method of the aerogel heat-insulating topcoat with both reflective heat insulation and thermal insulation effects according to claim 4, characterized in that, In step S2, the mass ratio of the titanium dioxide grafted with acrylic acid, styrene-acrylic emulsion, organosilicon hydrophobic additive, and ultraviolet absorber is (3-5):(25-35):(0.5-3):(0.5-2).

7. The preparation method of the aerogel thermal insulation topcoat with both reflective heat insulation and thermal insulation effects according to claim 4, characterized in that, In step S3, the mass ratio of titanium dioxide, film-forming aid, and organosilicon surface treatment agent is (5-70):(1-8):(1-15).

8. The preparation method of the aerogel thermal insulation topcoat with both reflective heat insulation and thermal insulation effects according to claim 4, characterized in that, In step S4, the mass ratio of the heavy calcium carbonate powder, film-forming aid, and organosilicon surface treatment agent is (5-70):(1-8):(1-15).

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