Chemical bond connection-based thermal insulation inorganic coating, preparation method and application

Abstract

The application relates to the technical field of inorganic coating, and discloses a heat-preservation inorganic coating based on chemical bond connection, a preparation method and application, which comprises the following steps: dispersing 100-500 parts of raw material aerogel-filler bond connection material, 100-400 parts of silicate, 20-50 parts of sol tackifier and solvent in accordance with the weight ratio to obtain a dispersed dispersion liquid; adding 10-50 parts of raw material cellulose, 5-20 parts of rare earth zirconate, 4-13 parts of an additive and solvent in accordance with the weight ratio to the dispersion liquid, and continuing to sufficiently disperse to obtain the required coating; wherein the solvent is 200-500 parts in accordance with the weight ratio; the aerogel-filler bond connection material is obtained by bond connection of amino-modified aerogel and aldehyde-modified filler; the coating obtained by the application has strong adhesion to the base material, low thermal conductivity, the lowest thermal conductivity can reach 0.038 W / m*K, and good environmental protection.

Description

Technical Field

[0001] This invention relates to the field of inorganic coating technology, specifically to a thermal insulation inorganic coating based on chemical bonding, its preparation method, and its application. Background Technology

[0002] Most existing coatings are organic-inorganic composites, containing 5-12% organic synthetic resin emulsions, with organic synthetic resin emulsions making up a significant portion of water-based coatings. Organic synthetic resin emulsions themselves have poor fire resistance, poor air permeability, and high VOC content. As people's environmental awareness gradually increases, their demand for healthy and green living is growing stronger, going beyond just material needs. Because commercially available water-based inorganic coatings contain some organic synthetic resin emulsions, their VOC content cannot be completely eliminated.

[0003] Currently, there is some research on environmentally friendly inorganic coatings, but existing inorganic coatings suffer from high thermal conductivity and low bonding strength. For example, CN115851010A discloses an inorganic coating, its preparation method, and its application, comprising: 50-90 parts of alkali metal silicate, 100-180 parts of inorganic oxide nanosol, 80-150 parts of emulsion, 150-250 parts of aerogel aqueous slurry, and 3-5 parts of short fibers; the mass ratio of the alkali metal silicate to the inorganic oxide nanosol is (0.3-0.6):1; the short fibers are wood fibers. Although thermal conductivity and bonding strength are improved to some extent, they are not ideal. Therefore, preparing an inorganic coating with better bonding strength, lower thermal conductivity, and environmental friendliness is an important research direction in this field. Summary of the Invention

[0004] This invention addresses the problems existing in the prior art by providing a thermal insulation inorganic coating based on chemical bonding, its preparation method, and its application.

[0005] The technical solution adopted in this invention is:

[0006] A method for preparing a thermally insulating inorganic coating based on chemical bonding includes the following steps:

[0007] The raw material aerogel-filler bonding material, silicate, sol thickener, and solvent are fully dispersed according to the following weight percentages to obtain a dispersion.

[0008] Add 10-50 parts by weight of raw material cellulose, 5-20 parts by weight of rare earth zirconate, 4-13 parts by weight of additives and solvent to the dispersion and continue to disperse thoroughly to obtain the desired coating.

[0009] The solvent is 200 to 500 parts by weight;

[0010] The aerogel-filler bonding material is obtained by linking amino-modified aerogel and aldehyde-modified filler through bonds.

[0011] Furthermore, the preparation process of the aerogel-filler bonded material is as follows:

[0012] Amino-modified aerogels and aldehyde-modified fillers were added to a solvent and refluxed for 6–24 h.

[0013] Add sodium borohydride and react for 4–10 hours. After filtering, washing and drying the product, the aerogel-filler bonded material can be obtained.

[0014] The molar ratio of amino-modified aerogel to aldehyde-modified filler is 1:1; the mass ratio of amino-modified aerogel to sodium borohydride is 1:3.

[0015] Furthermore, the preparation process of the amino-modified aerogel is as follows:

[0016] Aerogel and aminosilane coupling agent were added to the solvent and reacted at 60°C for 3–12 h.

[0017] After the reaction is complete, the product is filtered and dried to obtain an amino-modified aerogel.

[0018] Furthermore, the preparation process of the aldehyde-modified filler is as follows:

[0019] The filler and aminosilane coupling agent were added to the solvent and reacted at 60°C for 3–12 h.

[0020] Add flexible long-chain dialdehyde, react at room temperature for 2-8 hours, and the product can be filtered and dried to obtain aldehyde-modified filler.

[0021] Furthermore, the aerogel is composed of one or more of silica aerogel, zirconium dioxide aerogel, and aluminum oxide aerogel in any proportion.

[0022] The aminosilane coupling agent is composed of one or more of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, and 3-aminopropylmethyldiethoxysilane in any proportion.

[0023] Furthermore, the filler is composed of two or more of titanium dioxide, heavy calcium carbonate, attapulgite, and silica powder mixed in any proportion;

[0024] The aminosilane coupling agent is composed of one or more of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, and 3-aminopropylmethyldiethoxysilane in any proportion.

[0025] Flexible long-chain diols are terminal dialiphatic aldehydes with 4 to 12 carbon atoms.

[0026] A thermally insulating inorganic coating based on chemical bonding, comprising, by weight parts:

[0027] Aerogel-filler bonding material 100-500 parts, silicate 100-400 parts, sol thickener 20-50 parts, cellulose 10-50 parts, rare earth zirconate 5-20 parts, additives 4-13 parts, solvent 200-500 parts;

[0028] The aerogel-filler bonding material is obtained by linking amino-modified aerogel and aldehyde-modified filler through bonds.

[0029] Furthermore, the silicate is composed of one or more of potassium silicate, sodium silicate, and lithium silicate in any proportion.

[0030] Furthermore, the cellulose is composed of one or more of hydroxyethyl cellulose, hydroxypropyl cellulose, and methyl cellulose in any proportion; the rare earth zirconate is composed of one or more of lanthanum zirconate, yttrium zirconate, gadolinium zirconate, and lanthanum cerium zirconate in any proportion.

[0031] An application of a chemically bonded thermal insulation inorganic coating, wherein the chemically bonded thermal insulation inorganic coating is used to prepare a thermal insulation inorganic coating layer.

[0032] The beneficial effects of this invention are:

[0033] (1) In this invention, the aerogel component and the filler component form a stable CN covalent bond through a reduction Schiff base reaction, which realizes chemical bonding and enhances the interaction between inorganic components to form an aerogel-filler bonded material.

[0034] (2) In this invention, the flexible long chains between the aerogel component and the filler component in the aerogel-filler bonded material can be "woven" into the Si-O-Si network structure formed when the silicate film is formed, which further enhances the interaction between the components and achieves the purpose of not pulverizing, being difficult to fall off, and not requiring the addition of organic resin emulsion.

[0035] (3) In this invention, rare earth zirconate is used as a heat insulation effect regulator, which can effectively improve the high temperature resistance and corrosion resistance of the coating.

[0036] (4) The coating provided in this invention has the advantages of being VOC-free, having good thermal insulation effect, being flame-retardant and fire-resistant, and meeting the requirements of safety, environmental protection, energy saving and consumption reduction. Attached Figure Description

[0037] Figure 1 This is a schematic diagram of the aerogel-filler bonded connection material structure in this invention. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0039] A method for preparing a thermally insulating inorganic coating based on chemical bonding includes the following steps:

[0040] The raw material aerogel-filler bonding material, silicate, sol thickener, and solvent are fully dispersed according to the following weight percentages to obtain a dispersion.

[0041] Add 10-50 parts by weight of raw material cellulose, 5-20 parts by weight of rare earth zirconate, 4-13 parts by weight of additives and solvent to the dispersion and continue to disperse thoroughly to obtain the desired coating.

[0042] The solvent is 200 to 500 parts by weight, and the solvent is water.

[0043] like Figure 1 As shown, the aerogel-filler bonding material is obtained by linking amino-modified aerogel and aldehyde-modified filler through bonds.

[0044] The preparation process of aerogel-filler bonded materials is as follows:

[0045] Amino-modified aerogels and aldehyde-modified fillers were added to a solvent and refluxed for 6–24 h.

[0046] Add sodium borohydride and react for 4–10 hours. After filtering, washing and drying the product, the aerogel-filler bonded material can be obtained.

[0047] The molar ratio of amino-modified aerogel to aldehyde-modified filler is 1:1; the mass ratio of amino-modified aerogel to sodium borohydride is 1:3. The filler is composed of two or more of titanium dioxide, heavy calcium carbonate, attapulgite, and silica powder mixed in any proportion.

[0048] The preparation process of amino-modified aerogel is as follows:

[0049] Aerogel and aminosilane coupling agent were added to the solvent and reacted at 60°C for 3–12 h.

[0050] After the reaction is complete, the product is filtered and dried to obtain an amino-modified aerogel.

[0051] The preparation process of aldehyde-modified fillers is as follows:

[0052] The filler and aminosilane coupling agent were added to the solvent and reacted at 60°C for 3–12 h.

[0053] Add flexible long-chain dialdehyde, react at room temperature for 2-8 hours, and the product can be filtered and dried to obtain aldehyde-modified filler.

[0054] Aerogel is composed of one or more of silicon dioxide, zirconium dioxide, and aluminum oxide in any proportion;

[0055] The aminosilane coupling agent is composed of one or more of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, and 3-aminopropylmethyldiethoxysilane in any proportion.

[0056] The aminosilane coupling agent is composed of one or more of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, and 3-aminopropylmethyldiethoxysilane in any proportion.

[0057] Flexible long-chain diols are terminal dialiphatic aldehydes with 4 to 12 carbon atoms.

[0058] A thermally insulating inorganic coating based on chemical bonding, comprising, by weight parts:

[0059] The composition includes 100-500 parts of aerogel-filler bonding material, 100-400 parts of silicate, 20-50 parts of sol-gel thickener, 10-50 parts of cellulose, 5-20 parts of rare earth zirconate, 4-13 parts of additives, and 200-500 parts of solvent; the solvent is water.

[0060] For the sol-gel thickener, any existing product can be selected, such as Evonik Degussa. SIVO 112, Evonik Degussa SIVO 113, etc. The additives are dispersants and defoamers, with 3-10 parts by weight of dispersant and 1-3 parts by weight of defoamer. Existing products can be selected for dispersants, such as Nouryon Alcosperse 747 and Nouryon Alcosperse 797; existing products can be selected for defoamers, such as BASF FoamStar-SI 2293 and BASF FoamStar-SI 2299.

[0061] The aerogel-filler bonding material is obtained by linking amino-modified aerogel and aldehyde-modified filler through bonds.

[0062] Silicates are composed of one or more of potassium silicate, sodium silicate, and lithium silicate mixed in any proportion. Cellulose is composed of one or more of hydroxyethyl cellulose, hydroxypropyl cellulose, and methyl cellulose mixed in any proportion; rare earth zirconates are composed of one or more of lanthanum zirconate, yttrium zirconate, gadolinium zirconate, and lanthanum cerium zirconate mixed in any proportion.

[0063] Example 1

[0064] Prepare a chemically bonded thermal insulating inorganic coating according to the following steps:

[0065] First, amino-modified aerogels are prepared:

[0066] Five parts by mass of silica aerogel and one part by mass of 3-aminopropyltriethoxysilane were added to 30 parts by mass of 90% aqueous ethanol solution and reacted at 60°C for 6 hours.

[0067] After the reaction is complete, the product is filtered and dried to obtain amino-modified silica aerogel.

[0068] Then, aldehyde-modified fillers were prepared:

[0069] A filler consisting of 3 parts by weight of titanium dioxide and 2 parts by weight of heavy calcium carbonate was added to 30 parts by weight of a 90% aqueous ethanol solution containing 1 part by weight of 3-aminopropyltriethoxysilane. The reaction was carried out at 60°C for 6 hours.

[0070] Two parts by mass of glutaraldehyde were added, and the mixture was reacted at room temperature for 3 hours. The product was filtered and dried naturally to obtain the aldehyde-modified filler.

[0071] Preparation of aerogel-filler bonded materials:

[0072] Amino-modified silica aerogel and aldehyde-modified filler were added to anhydrous ethanol and stirred and refluxed for 12 hours.

[0073] After cooling to room temperature, sodium borohydride was added, and the reaction was carried out for 6 hours. The product was filtered, washed, and then vacuum dried at 80°C for 3 hours to obtain the aerogel-filler bonded material. The molar ratio of amino-modified silica aerogel to aldehyde-modified filler was 1:1, and the mass ratio of amino-modified silica aerogel to sodium borohydride was 1:3.

[0074] Weigh each raw material according to the following parts by weight:

[0075] 300 parts of aerogel-filler bonding material, 150 parts of silicate, and Evonik Degussa 35 parts of SIVO 112 sol thickener were added to 380 parts of water and dispersed at high speed for 20 minutes to obtain a dispersion.

[0076] Add 20 parts of hydroxyethyl cellulose, 12 parts of lanthanum zirconate, 6 parts of Noryon Alcosperse 747 dispersant, and 2 parts of BASF FoamStar-SI 2293 defoamer to the dispersion, continue high-speed dispersion for 30 minutes, and then grind to obtain a chemically bonded thermal insulation inorganic coating.

[0077] Example 2

[0078] Prepare a chemically bonded thermal insulating inorganic coating according to the following steps:

[0079] First, amino-modified aerogels are prepared:

[0080] Five parts by mass of zirconium dioxide aerogel and one part by mass of 3-aminopropylmethyldimethoxysilane were added to 30 parts by mass of 90% aqueous ethanol solution and reacted at 60°C for 6 hours.

[0081] After the reaction was complete, the product was filtered and dried to obtain amino-modified zirconium dioxide aerogel.

[0082] Then, aldehyde-modified fillers were prepared:

[0083] A filler consisting of 3 parts by weight of titanium dioxide and 2 parts by weight of heavy calcium carbonate was added to 30 parts by weight of a 90% aqueous ethanol solution containing 1 part by weight of 3-aminopropylmethyldimethoxysilane. The reaction was carried out at 60°C for 6 hours.

[0084] Two parts by mass of succinaldehyde were added, and the mixture was reacted at room temperature for 3 hours. The product was filtered and dried naturally to obtain the aldehyde-modified filler.

[0085] Preparation of aerogel-filler bonded materials:

[0086] Amino-modified zirconium dioxide aerogel and aldehyde-modified filler were added to anhydrous ethanol and stirred and refluxed for 12 hours.

[0087] After cooling to room temperature, sodium borohydride was added, and the reaction was carried out for 6 hours. The product was filtered, washed, and then vacuum dried at 80°C for 3 hours to obtain the aerogel-filler bonded material. The molar ratio of amino-modified silica aerogel to aldehyde-modified filler was 1:1, and the mass ratio of amino-modified silica aerogel to sodium borohydride was 1:3.

[0088] Weigh each raw material according to the following parts by weight:

[0089] 300 parts of aerogel-filler bonding material, 150 parts of silicate, and Evonik Degussa 35 parts of SIVO 112 sol thickener were added to 380 parts of water and dispersed at high speed for 20 minutes to obtain a dispersion.

[0090] Add 20 parts of hydroxypropyl cellulose, 12 parts of yttrium zirconate, 6 parts of Noryon Alcosperse 797 dispersant, and 2 parts of BASF FoamStar-SI 2299 defoamer to the dispersion, continue high-speed dispersion for 30 minutes, and grind to obtain a chemically bonded thermal insulation inorganic coating.

[0091] Example 3

[0092] Prepare a chemically bonded thermal insulating inorganic coating according to the following steps:

[0093] First, amino-modified aerogels are prepared:

[0094] Five parts by mass of silica aerogel and one part by mass of 3-aminopropyltriethoxysilane were added to 30 parts by mass of 90% ethanol aqueous solution and reacted at 60°C for 12 h.

[0095] After the reaction is complete, the product is filtered and dried to obtain amino-modified silica aerogel.

[0096] Then, aldehyde-modified fillers were prepared:

[0097] A filler consisting of 3 parts by mass of titanium dioxide and 2 parts by mass of attapulgite was added to 30 parts by mass of a 90% ethanol aqueous solution containing 1 part by mass of 3-aminopropyltriethoxysilane. The reaction was carried out at 60°C for 3 hours.

[0098] Two parts by mass of glutaraldehyde were added, and the mixture was reacted at room temperature for 8 hours. The product was filtered and dried naturally to obtain the aldehyde-modified filler.

[0099] Preparation of aerogel-filler bonded materials:

[0100] Amino-modified silica aerogel and aldehyde-modified filler were added to anhydrous ethanol and stirred and refluxed for 24 hours.

[0101] After cooling to room temperature, sodium borohydride was added, and the reaction was carried out for 4 hours. The product was filtered, washed, and then vacuum dried at 80°C for 3 hours to obtain the aerogel-filler bonded material. The molar ratio of amino-modified silica aerogel to aldehyde-modified filler was 1:1, and the mass ratio of amino-modified silica aerogel to sodium borohydride was 1:3.

[0102] Weigh each raw material according to the following parts by weight:

[0103] 300 parts of aerogel-filler bonding material, 150 parts of silicate, and Evonik Degussa 35 parts of SIVO 112 sol thickener were added to 380 parts of water and dispersed at high speed for 30 minutes to obtain a dispersion.

[0104] Add 20 parts of methylcellulose, 12 parts of gadolinium zirconate, 6 parts of Noryon Alcosperse 747 dispersant, and 2 parts of BASF FoamStar-SI 2293 defoamer to the dispersion, continue high-speed dispersion for 20 minutes, and grind to obtain a chemically bonded thermal insulation inorganic coating.

[0105] Example 4

[0106] Prepare a chemically bonded thermal insulating inorganic coating according to the following steps:

[0107] First, amino-modified aerogels are prepared:

[0108] Five parts by mass of silica aerogel and one part by mass of 3-aminopropylmethyldimethoxysilane were added to 30 parts by mass of 90% aqueous ethanol solution and reacted at 60°C for 3 hours.

[0109] After the reaction is complete, the product is filtered and dried to obtain amino-modified silica aerogel.

[0110] Then, aldehyde-modified fillers were prepared:

[0111] A filler consisting of 3 parts by weight of titanium dioxide and 2 parts by weight of heavy calcium carbonate was added to 30 parts by weight of a 90% aqueous ethanol solution containing 1 part by weight of 3-aminopropylmethyldimethoxysilane. The reaction was carried out at 60°C for 12 hours.

[0112] Two parts by mass of glutaraldehyde were added, and the mixture was reacted at room temperature for 2 hours. The product was filtered and dried naturally to obtain the aldehyde-modified filler.

[0113] Preparation of aerogel-filler bonded materials:

[0114] Amino-modified silica aerogel and aldehyde-modified filler were added to anhydrous ethanol and stirred and refluxed for 6 hours.

[0115] After cooling to room temperature, sodium borohydride was added, and the reaction was carried out for 10 hours. The product was filtered, washed, and then vacuum dried at 80°C for 3 hours to obtain the aerogel-filler bonded material. The molar ratio of amino-modified silica aerogel to aldehyde-modified filler was 1:1, and the mass ratio of amino-modified silica aerogel to sodium borohydride was 1:3.

[0116] Weigh each raw material according to the following parts by weight:

[0117] 300 parts of aerogel-filler bonding material, 150 parts of silicate, and Evonik Degussa 35 parts of SIVO 112 sol thickener were added to 380 parts of water and dispersed at high speed for 10 minutes to obtain a dispersion.

[0118] Add 20 parts of hydroxyethyl cellulose, 12 parts of lanthanum zirconate, 6 parts of Noryon Alcosperse 747 dispersant, and 2 parts of BASF FoamStar-SI 2293 defoamer to the dispersion, continue high-speed dispersion for 10 minutes, and grind to obtain a chemically bonded thermal insulation inorganic coating.

[0119] Example 5

[0120] Prepare a chemically bonded thermal insulating inorganic coating according to the following steps:

[0121] First, amino-modified aerogels are prepared:

[0122] Five parts by mass of silica aerogel and one part by mass of 3-aminopropyltriethoxysilane were added to 30 parts by mass of 90% aqueous ethanol solution and reacted at 60°C for 6 hours.

[0123] After the reaction is complete, the product is filtered and dried to obtain amino-modified silica aerogel.

[0124] Then, aldehyde-modified fillers were prepared:

[0125] A filler consisting of 3 parts by weight of titanium dioxide and 2 parts by weight of heavy calcium carbonate was added to 30 parts by weight of a 90% aqueous ethanol solution containing 1 part by weight of 3-aminopropyltriethoxysilane. The reaction was carried out at 60°C for 6 hours.

[0126] Two parts by mass of glutaraldehyde were added, and the mixture was reacted at room temperature for 3 hours. The product was filtered and dried naturally to obtain the aldehyde-modified filler.

[0127] Preparation of aerogel-filler bonded materials:

[0128] Amino-modified silica aerogel and aldehyde-modified filler were added to anhydrous ethanol and stirred and refluxed for 12 hours.

[0129] After cooling to room temperature, sodium borohydride was added, and the reaction was carried out for 6 hours. The product was filtered, washed, and then vacuum dried at 80°C for 3 hours to obtain the aerogel-filler bonded material. The molar ratio of amino-modified silica aerogel to aldehyde-modified filler was 1:1, and the mass ratio of amino-modified silica aerogel to sodium borohydride was 1:3.

[0130] Weigh each raw material according to the following parts by weight:

[0131] 500 parts of aerogel-filler bonding material, 100 parts of silicate, and Evonik Degussa. Add 20 parts of SIVO 112 sol thickener to 500 parts of water and disperse at high speed for 20 minutes to obtain a dispersion.

[0132] Add 50 parts of hydroxyethyl cellulose, 5 parts of lanthanum zirconate, 10 parts of Noryon Alcosperse 747 dispersant, and 3 parts of BASF FoamStar-SI 2293 defoamer to the dispersion, continue high-speed dispersion for 30 minutes, and then grind to obtain a chemically bonded thermal insulation inorganic coating.

[0133] Example 6

[0134] Prepare a chemically bonded thermal insulating inorganic coating according to the following steps:

[0135] First, amino-modified aerogels are prepared:

[0136] Five parts by mass of silica aerogel and one part by mass of 3-aminopropyltriethoxysilane were added to 30 parts by mass of 90% aqueous ethanol solution and reacted at 60°C for 6 hours.

[0137] After the reaction is complete, the product is filtered and dried to obtain amino-modified silica aerogel.

[0138] Then, aldehyde-modified fillers were prepared:

[0139] A filler consisting of 3 parts by weight of titanium dioxide and 2 parts by weight of heavy calcium carbonate was added to 30 parts by weight of a 90% aqueous ethanol solution containing 1 part by weight of 3-aminopropyltriethoxysilane. The reaction was carried out at 60°C for 6 hours.

[0140] Two parts by mass of glutaraldehyde were added, and the mixture was reacted at room temperature for 3 hours. The product was filtered and dried naturally to obtain the aldehyde-modified filler.

[0141] Preparation of aerogel-filler bonded materials:

[0142] Amino-modified silica aerogel and aldehyde-modified filler were added to anhydrous ethanol and stirred and refluxed for 12 hours.

[0143] After cooling to room temperature, sodium borohydride was added, and the reaction was carried out for 6 hours. The product was filtered, washed, and then vacuum dried at 80°C for 3 hours to obtain the aerogel-filler bonded material. The molar ratio of amino-modified silica aerogel to aldehyde-modified filler was 1:1, and the mass ratio of amino-modified silica aerogel to sodium borohydride was 1:3.

[0144] Weigh each raw material according to the following parts by weight:

[0145] 100 parts of aerogel-filler bonding material, 400 parts of silicate, and Evonik Degussa. Add 50 parts of SIVO 112 sol thickener to 200 parts of water and disperse at high speed for 20 minutes to obtain a dispersion.

[0146] Add 10 parts of hydroxyethyl cellulose, 20 parts of lanthanum zirconate, 3 parts of Noryon Alcosperse 747 dispersant, and 1 part of BASF FoamStar-SI 2293 defoamer to the dispersion, continue high-speed dispersion for 30 minutes, and grind to obtain a chemically bonded thermal insulation inorganic coating.

[0147] Comparative Example

[0148] Weigh each raw material according to the following parts by weight:

[0149] 150 parts silica aerogel, 90 parts titanium dioxide, 60 parts heavy calcium carbonate, 150 parts silicate, Evonik Degussa 35 parts of SIVO 112 sol thickener were added to 380 parts of water and dispersed at high speed for 20 minutes to obtain a dispersion.

[0150] Add 20 parts of hydroxyethyl cellulose, 12 parts of lanthanum zirconate, 6 parts of Noryon Alcosperse 747 dispersant, and 2 parts of BASF FoamStar-SI 2293 defoamer to the dispersion, continue high-speed dispersion for 30 minutes, and then grind to obtain the inorganic coating.

[0151] The coating prepared above was applied to the surface of the substrate and dried at room temperature for 3 days. Performance tests were then conducted, and the results are shown in Table 1. The method for testing thermal conductivity was GB / T10295-2008, and the method for water resistance (360h) was JG / T26-2002. The method for wash resistance (cycles) was GB / T9266-2009, and the methods for TVOC (g / L) and free formaldehyde (g / L) were GB18582-2020.

[0152] Table 1. Performance Test Results

[0153]

[0154] In this invention, the aerogel component and the filler component form stable CN covalent bonds through a reducing Schiff base reaction, achieving chemical bonding and enhancing the interaction between inorganic components to form an aerogel-filler bonded material. The flexible long chains between the aerogel and filler components in the aerogel-filler bonded material can be "woven" into the Si-O-Si network structure formed during silicate film formation, further enhancing the interaction between the components and achieving the goals of non-powdering, difficult detachment, and no need to add organic resin emulsions. Rare earth zirconate, as a heat insulation effect modifier, can effectively improve the high-temperature resistance and corrosion resistance of the coating. The provided coating has advantages such as being VOC-free, having good thermal insulation effect, and being flame-retardant and fire-resistant, meeting the requirements of safety, environmental protection, energy conservation, and consumption reduction.

Claims

1. A method for preparing a thermally insulating inorganic coating based on chemical bonding, characterized in that, Includes the following steps: The raw material aerogel-filler bonding material, silicate, sol thickener, and solvent are fully dispersed according to the following weight percentages to obtain a dispersion. Add 10-50 parts by weight of raw material cellulose, 5-20 parts by weight of rare earth zirconate, 4-13 parts by weight of additives and solvent to the dispersion and continue to disperse thoroughly to obtain the desired coating. The solvent is 200 to 500 parts by weight; The aerogel-filler bonding material is obtained by linking amino-modified aerogel and aldehyde-modified filler through bonds.

2. The method for preparing a thermally insulating inorganic coating based on chemical bonding according to claim 1, characterized in that, The preparation process of the aerogel-filler bonded material is as follows: Amino-modified aerogels and aldehyde-modified fillers were added to a solvent and refluxed for 6–24 h. Add sodium borohydride and react for 4–10 h. After filtering, washing and drying the product, the aerogel-filler bonded material can be obtained. The molar ratio of amino-modified aerogel to aldehyde-modified filler is 1:1; the mass ratio of amino-modified aerogel to sodium borohydride is 1:

3.

3. The method for preparing a thermally insulating inorganic coating based on chemical bonding according to claim 2, characterized in that, The preparation process of the amino-modified aerogel is as follows: Aerogel and aminosilane coupling agent were added to the solvent and reacted at 60 °C for 3–12 h. After the reaction is complete, the product is filtered and dried to obtain an amino-modified aerogel.

4. The method for preparing a thermally insulating inorganic coating based on chemical bonding according to claim 2, characterized in that, The preparation process of the aldehyde-modified filler is as follows: The filler and aminosilane coupling agent were added to the solvent and reacted at 60 °C for 3–12 h. Add flexible long-chain dialdehyde, react at room temperature for 2–8 h, and the product can be filtered and dried to obtain aldehyde-modified filler.

5. The method for preparing a thermally insulating inorganic coating based on chemical bonding according to claim 3, characterized in that, The aerogel is composed of one or more of silica aerogel, zirconium dioxide aerogel, and aluminum oxide aerogel in any proportion. The aminosilane coupling agent is composed of one or more of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, and 3-aminopropylmethyldiethoxysilane in any proportion.

6. The method for preparing a thermally insulating inorganic coating based on chemical bonding according to claim 4, characterized in that, The filler is composed of two or more of titanium dioxide, heavy calcium carbonate, attapulgite, and silica powder in any proportion. The aminosilane coupling agent is composed of one or more of 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropylmethyldimethoxysilane, and 3-aminopropylmethyldiethoxysilane in any proportion. Flexible long-chain dialdehydes are terminal dialiphatic aldehydes with 4 to 12 carbon atoms.

7. The thermal insulation inorganic coating based on chemical bonding obtained by any one of the preparation methods of claims 1 to 6, characterized in that, Including by weight parts: Aerogel-filler bonding material 100-500 parts, silicate 100-400 parts, sol thickener 20-50 parts, cellulose 10-50 parts, rare earth zirconate 5-20 parts, additives 4-13 parts, solvent 200-500 parts; The aerogel-filler bonding material is obtained by linking amino-modified aerogel and aldehyde-modified filler through bonds.

8. The thermal insulation inorganic coating based on chemical bonding according to claim 7, characterized in that, The silicate is composed of one or more of potassium silicate, sodium silicate, and lithium silicate in any proportion.

9. The thermal insulation inorganic coating based on chemical bonding according to claim 7, characterized in that, The cellulose is composed of one or more of hydroxyethyl cellulose, hydroxypropyl cellulose, and methyl cellulose in any proportion; the rare earth zirconate is composed of one or more of lanthanum zirconate, yttrium zirconate, gadolinium zirconate, and lanthanum cerium zirconate in any proportion.

10. The application of the thermal insulation inorganic coating based on chemical bonding as described in any one of claims 7 to 9, characterized in that, The thermally insulating inorganic coating based on chemical bonding is used to prepare a thermally insulating inorganic coating.

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