Lightweight high-efficiency thermal insulation coating and preparation method and application thereof

Abstract

The application belongs to the technical field of building coating and specifically discloses a light-feeling high-efficiency thermal insulation coating which comprises a middle layer coating and a surface layer coating, wherein the surface layer coating comprises the following components in mass fraction: pure acrylic emulsion, acrylic ester monomer, modified silicon dioxide, titanium white, auxiliary agent, initiator and water; the modified silicon dioxide is introduced into the surface layer coating, on one hand, the saturated alkyl chains are grafted on the silicon dioxide, the hydrophobicity of the modified silicon dioxide is improved, the compatibility between the modified silicon dioxide and other components in the surface layer coating is improved, the modified silicon dioxide is more stably and uniformly suspended in the system, the stability of the product is improved, and the appearance of the product is ensured; on the other hand, the unsaturated alkyl chains are partially grafted on the modified silicon dioxide, and the compatibility between the modified silicon dioxide and other components is further improved.

Description

Technical Field

[0001] This invention belongs to the field of architectural coatings technology, specifically relating to a lightweight, textured, high-efficiency thermal insulation coating, its preparation method, and its application. Background Technology

[0002] With the increasing emphasis placed on energy conservation and environmental protection by the nation, the requirements for building energy efficiency are also becoming more stringent, leading to the emergence of energy-saving solutions for building exterior walls. Affected by the greenhouse effect and continuous urbanization, most parts of my country have experienced sustained high temperatures in summer in recent years, resulting in a sharp increase in air conditioning energy consumption.

[0003] Existing thermal insulation coatings primarily achieve their insulation effect by increasing thickness and using a passive, barrier-like approach. However, this method often reduces the coating's safety, leading to drawbacks such as excessive thickness, easy peeling and difficulty in repair, poor appearance, and susceptibility to cracking. Meanwhile, among the many thermal insulation coatings available, textured coatings are favored by the market due to their rich artistic expression, allowing for the creation of various three-dimensional and fashionable artistic effects using different application tools and techniques. However, the unique three-dimensional texture and rough, uneven surface of textured thermal insulation coatings make them prone to dust accumulation and contamination; they also fail to effectively reflect sunlight for reflective insulation, and their insulation performance is affected by atmospheric conditions and dust. Based on these numerous technical problems, traditional thermal insulation coatings struggle to meet the increasingly stringent thermal insulation requirements of buildings. Therefore, developing a new type of lightweight, textured thermal insulation coating has become a top priority for the development of green and energy-efficient buildings.

[0004] This invention addresses the existing technical problems by providing a lightweight, textured, high-efficiency thermal insulation coating and its preparation method. It effectively solves the problems of excessively thick coatings and easy peeling, resulting in a lightweight, flexible, crack-resistant coating with excellent appearance and stain resistance. It is particularly important to emphasize that this lightweight, textured thermal insulation coating exhibits superior thermal insulation performance, effectively reducing heat conduction and lowering the heat exchange efficiency between the coating and surrounding environments. This breaks through the traditional "thicker, better insulation" model, providing a more efficient and safer energy-saving method for green buildings and ultra-low energy consumption buildings. Summary of the Invention

[0005] This invention aims to address the aforementioned deficiencies. The topcoat provided by this technical solution is a blend of pure acrylic emulsion and modified silica, giving the coating high hardness, excellent adhesion, and superior long-lasting hydrophobicity. This results in a coating with low water absorption, preventing rainwater from easily penetrating the coating for protection, and also excellent stain resistance, effectively improving sunlight reflection for reflective heat insulation. Secondly, infrared reflective heat-insulating titanium dioxide, nuclear titanium dioxide, and aerogel dispersion are used as the main materials for light reflection and heat insulation, giving the coating excellent light and heat reflection effects. Furthermore, the added adhesion promoter synergistically interacts with the pure acrylic emulsion, promoting bonding between the topcoat and intermediate coating layers, allowing the two layers to better penetrate and fuse together, forming a unified coating that effectively increases light reflection performance and improves heat insulation performance.

[0006] The specific plan is as follows:

[0007] One object of the present invention is to provide a lightweight, high-efficiency thermal insulation coating, wherein the lightweight, high-efficiency thermal insulation coating comprises a middle layer coating and a top layer coating, wherein:

[0008] The topcoat coating comprises the following components by mass fraction:

[0009]

[0010] The modified silica is obtained by grafting silica with a mixture of unsaturated fatty acids; the content of the unsaturated fatty acids is 10-15 wt% of the total fatty acids.

[0011] Furthermore, the acrylate monomer is selected from one or more of butyl acrylate, propyl acrylate, and ethyl acrylate.

[0012] Furthermore, the additives are selected from one or more of the following: defoamers, adhesion promoters, thickeners, leveling agents, bactericides, dispersants, wetting agents, film-forming aids, aerogel dispersions, hollow glass microspheres, cellulose, and defoamers.

[0013] Furthermore, the intermediate coating comprises the following components by mass fraction:

[0014]

[0015]

[0016] Specifically, the aerogel dispersion used in the intermediate coating of this invention has a low density, which reduces the weight of the coating, and a low thermal conductivity, which reduces heat radiation, heat conduction, and air convection, thus improving the thermal insulation effect. Furthermore, the combined use of the aerogel dispersion and hollow glass microspheres effectively enhances the thermal insulation performance of the intermediate coating. Additionally, the addition of bentonite improves the thixotropy of the coating, enhancing its workability. Finally, through rational optimization of the technical formulation, the intermediate coating not only produces a lightweight coating with a good appearance and a dense, smooth film after application, but also possesses excellent workability, adhesion, and thermal insulation performance.

[0017] Furthermore, the titanium dioxide is selected from one or more of nuclear titanium dioxide and infrared reflective titanium dioxide.

[0018] Specifically, the infrared-reflecting titanium dioxide is a rutile titanium dioxide with the ability to reflect solar energy, and it also has excellent weather resistance.

[0019] Specifically, the nuclear titanium dioxide is a novel multi-component polymeric powder material with excellent dispersibility, wettability, and hiding power.

[0020] Furthermore, the pure acrylic emulsion is an emulsion based on acrylic polymer, which has high hardness and excellent adhesion and mechanical stability.

[0021] Furthermore, the aerogel dispersion is a paste-like substance with the characteristics of light weight and good thermal insulation performance.

[0022] Furthermore, the dispersant is selected from sodium or potassium polycarboxylate dispersants with hydrophobic modified structures, which have excellent water resistance and extremely high dispersion efficiency.

[0023] Furthermore, the wetting agent is selected from one or both of anionic surfactants and nonionic surfactants.

[0024] Furthermore, the defoamer is one or both of mineral oil defoamers and organosilicon defoamers.

[0025] Furthermore, the bactericide is selected from one or two of isothiazolinones, benzisothiazoline pyridines, or triazines.

[0026] Furthermore, the polyurethane thickener is a water-based nonionic associative hydrophobic modified polyurethane, which has excellent compatibility, thickening and leveling properties, and water and alkali resistance.

[0027] Furthermore, the adhesion promoter is a nonionic compound that does not contain polysiloxane, and has high adhesion and bonding strength, which can greatly improve the adhesion between coatings.

[0028] Furthermore, the leveling agent is a substance that can effectively reduce the surface tension of the coating film and improve its leveling and uniformity.

[0029] Furthermore, the hollow glass microspheres are white, spherical, glassy, ​​lightweight powder materials with low density and heat resistance and insulation properties.

[0030] Furthermore, the bentonite shown is a high-purity synthetic bentonite with excellent thickening, anti-settling, and anti-sagging properties.

[0031] The present invention also provides a method for preparing the lightweight, high-efficiency thermal insulation coating, the method comprising the following steps:

[0032] S1. Hydroxylated silica is immersed in a solution of unsaturated fatty acids and saturated fatty acids, ultrasonically heated, and dried to obtain the modified silica.

[0033] S2. The modified silica is blended with other components to obtain the topcoat coating.

[0034] Furthermore, the unsaturated fatty acid is selected from one or more of oleic acid, linoleic acid, or linolenic acid.

[0035] Furthermore, the saturated fatty acid is selected from one or more of lauric acid, stearic acid, and palmitic acid.

[0036] Furthermore, in step S1, the heating temperature is 70-80°C.

[0037] The present invention also provides an application of a lightweight, high-efficiency thermal insulation coating, comprising applying the topcoat coating onto the intermediate coating and then photocuring it.

[0038] The lightweight, textured thermal insulation coating provided by this invention has excellent thermal insulation performance, effectively reducing heat conduction and lowering the heat exchange efficiency of the environment on both sides of the coating. It breaks through the traditional "the thicker the coating, the better the insulation" model, providing a more efficient and safer energy-saving method for green buildings and ultra-low energy consumption buildings.

[0039] The present invention has the following beneficial effects: By introducing modified silica into the topcoat, the present invention, on the one hand, grafts saturated alkyl chains onto the silica, which can improve the hydrophobicity of the modified silica, thereby improving its compatibility with other components in the topcoat. This facilitates a more stable and uniform suspension of the modified silica in the system, thus improving the stability of the product and ensuring its appearance. On the other hand, by partially grafting unsaturated alkyl chains onto the modified silica, its compatibility with other components can be further improved. At the same time, silica can be introduced into the random copolymer formed by acrylate monomers through covalent bonds, which also greatly improves the dispersibility of silica in the coating and prevents the surface migration of modified silica that would lead to a decline in coating performance. This effectively changes the compatibility between the components of the coating, further improving the adhesion between the topcoat and the intermediate coating, thereby improving the durability of the coating. Detailed Implementation

[0040] The present invention will now be described in detail with reference to embodiments to facilitate understanding of the invention by those skilled in the art. It is particularly important to note that the embodiments are merely illustrative of the invention and should not be construed as limiting the scope of protection of the invention. Non-essential improvements and adjustments made to the invention by those skilled in the art based on the above description should still fall within the scope of protection of the invention. Furthermore, all raw materials mentioned below, unless otherwise specified, are commercially available products; and all process steps or preparation methods not mentioned in detail are process steps or preparation methods known to those skilled in the art.

[0041] In this embodiment of the invention,

[0042] The pure acrylic emulsion was selected from Badifu RS706T;

[0043] Infrared reflective titanium dioxide is selected from Huntsman Altiriris 550;

[0044] The nuclear titanium dioxide is selected from RTR202 of Foshan Jianfa Ruitong Technology Co., Ltd.;

[0045] Hydroxyethyl cellulose was selected from Lotte Samsung B30K;

[0046] The dispersant was selected from Gaotai P30;

[0047] The wetting agent is Clariant LCN070;

[0048] Alcohol ester twelve is selected from Eastman TEXANOL;

[0049] The aerogel dispersion was selected from KNF-G of Anhui Keang Nanotechnology Co., Ltd.

[0050] The defoamer was selected from Puwei DF-8606;

[0051] The adhesion promoter is Momentive A-187;

[0052] The polyurethane thickener was selected from Rohm and Haas RM-8W;

[0053] The leveling agent is selected from Rohm and Haas RM-2020;

[0054] The bactericide was selected from Tor Specialty Chemicals (Zhenjiang) Co., Ltd. EG-CLF;

[0055] Hollow glass microspheres were selected from 20P1000Q from Suzhou Junda New Materials Co., Ltd.

[0056] The wood fiber is selected from PWC500 by Guangdong Longhu Technology Co., Ltd.;

[0057] The bentonite was selected from Shanghai Grid International Trade MZ;

[0058] The initiator is photoinitiator 1173, selected from Jiuri New Materials.

[0059] The composition of the intermediate coating is shown in Table 1:

[0060] Table 1. Composition and mass fraction of intermediate layer coating

[0061]

[0062]

[0063] The preparation method of the intermediate coating material is as follows:

[0064] A1. Add hydroxyethyl cellulose to deionized water according to the above mass fraction, stir and disperse evenly, then slowly add pure acrylic emulsion in sequence, stir and disperse evenly, then slowly add dispersant, wetting agent, alcohol ester dodecyl, propylene glycol, defoamer and 2-amino-2-methyl-1-propanol in sequence, and stir and disperse evenly at 500 r / min.

[0065] A2. Then add the aerogel dispersion paste, bentonite, and wood fiber in sequence, and stir at 700 r / min to disperse evenly;

[0066] A3. Add hollow glass microspheres sequentially and stir at 800 r / min until evenly dispersed;

[0067] A4. Add the remaining ingredients and stir at 600 r / min until evenly dispersed to obtain the intermediate coating.

[0068] Example 1

[0069] A lightweight, high-efficiency thermal insulation coating, comprising a middle layer coating and a top layer coating, wherein:

[0070] The topcoat coating comprises the following components by mass fraction:

[0071]

[0072]

[0073] The modified silica is obtained by grafting a mixture of unsaturated fatty acids onto silica.

[0074] The preparation method of the lightweight, high-efficiency thermal insulation coating includes the following steps:

[0075] S1-1. Add 6g of silicon dioxide to a mixture of 70wt% concentrated sulfuric acid and 30wt% hydrogen peroxide, soak for 12h, then wash 5 times with distilled water and dry at 60℃ for 24h to obtain hydroxylated silicon dioxide.

[0076] S1-2. The hydroxylated silica is immersed in a sufficient amount of ethanol containing a mixture of oleic acid and stearic acid (1:5, m / m) (ensuring the solute content is 30wt%), ultrasonically heated at 75°C for 1 hour, centrifuged, washed, and dried to obtain the modified silica.

[0077] S2. The modified silica is blended with other components according to the above mass fraction to obtain the topcoat coating.

[0078] Specifically,

[0079] S2-1. Add hydroxyethyl cellulose to deionized water and stir to disperse evenly. Then slowly add dispersant, wetting agent, defoamer, alcohol ester dodecyl, propylene glycol, and 2-amino-2-methyl-1-propanol in sequence and stir to disperse evenly.

[0080] S2-2, then slowly add infrared reflective titanium dioxide, nuclear titanium dioxide, aerogel dispersion paste, and modified silica in sequence, and stir to disperse evenly;

[0081] S2-3. Slowly add pure acrylic emulsion and butyl acrylate, stir and disperse evenly, then add the remaining ingredients and replenish the remaining deionized water in sequence, stir evenly, and then heat to 80℃ for 5 hours under nitrogen atmosphere to obtain the topcoat coating.

[0082] Example 2

[0083] A lightweight, high-efficiency thermal insulation coating, comprising a middle layer coating and a top layer coating, wherein:

[0084] The topcoat coating comprises the following components by mass fraction:

[0085]

[0086]

[0087] The modified silica is obtained by grafting a mixture of unsaturated fatty acids onto silica.

[0088] The preparation method of the lightweight, high-efficiency thermal insulation coating includes the following steps:

[0089] S1-1. Add 6g of silicon dioxide to a mixture of 70wt% concentrated sulfuric acid and 30wt% hydrogen peroxide, soak for 12h, then wash 5 times with distilled water and dry at 60℃ for 24h to obtain hydroxylated silicon dioxide.

[0090] S1-2. The hydroxylated silica is immersed in a sufficient amount of ethanol containing a mixture of oleic acid and stearic acid (1:5, m / m) (ensuring the solute content is 30wt%), ultrasonically heated at 75°C for 1 hour, centrifuged, washed, and dried to obtain the modified silica.

[0091] S2. The modified silica is blended with other components according to the above mass fraction to obtain the topcoat coating.

[0092] For the specific steps of S2, please refer to Example 1.

[0093] Example 3

[0094] A lightweight, high-efficiency thermal insulation coating, comprising a middle layer coating and a top layer coating, wherein:

[0095] The topcoat coating comprises the following components by mass fraction:

[0096]

[0097]

[0098] The modified silica is obtained by grafting a mixture of unsaturated fatty acids onto silica.

[0099] The preparation method of the lightweight, high-efficiency thermal insulation coating includes the following steps:

[0100] S1-1. Add 6g of silicon dioxide to a mixture of 70wt% concentrated sulfuric acid and 30wt% hydrogen peroxide, soak for 12h, then wash 5 times with distilled water and dry at 60℃ for 24h to obtain hydroxylated silicon dioxide.

[0101] S1-2. The hydroxylated silica is immersed in a sufficient amount of ethanol containing a mixture of oleic acid and stearic acid (1:5, m / m) (ensuring the solute content is 30wt%), ultrasonically heated at 75°C for 1 hour, centrifuged, washed, and dried to obtain the modified silica.

[0102] S2. The modified silica is blended with other components according to the above mass fraction to obtain the topcoat coating.

[0103] For the specific steps of S2, please refer to Example 1.

[0104] Comparative Example 1

[0105] The difference between Comparative Example 1 and Example 1 is that the raw materials for preparing the lightweight high-efficiency thermal insulation coating of Comparative Example 1 did not use modified silica, but instead used silica of equal mass instead of modified silica. All other components were the same as those in Example 1.

[0106] Comparative Example 2

[0107] The difference between Comparative Example 2 and Example 1 is that stearic acid of equal mass is used instead of oleic acid in steps S1-2, while the other components are the same as in Example 1.

[0108] Performance testing

[0109] Test method:

[0110] The intermediate coating was applied to a 20*30cm cement board. After drying, it was sanded smooth with 600-grit sandpaper. The topcoat coatings prepared in Examples 1-3 and Comparative Examples 1-2 were then rolled onto the intermediate coating using a roller. The coating was then irradiated for 10 seconds under a 1000W high-pressure UV mercury lamp to obtain a heat-insulating coating.

[0111] Among them, the weight of cement board m1 and the weight of cement board coated with paint m2 were weighed using an electronic scale, and the weight of the coating was...

[0112] Δm = m2 - m1;

[0113] According to the technical requirements of JG / T 24-2018 for synthetic resin sand-textured architectural coatings, the workability, coating appearance, bond strength, water absorption and stain resistance of the products in Examples 1-3 and Comparative Examples 1-2 were tested.

[0114] According to the technical requirements of JC / T 1040-2020 for heat-reflective insulating coatings for building exterior surfaces (textured type), the brightness value, solar reflectance, near-infrared reflectance, solar reflectance retention rate after pollution, and thermal insulation temperature difference with the reference blackboard of the products of Examples 1-3 and Comparative Examples 1-2 were tested. The results are shown in Table 2.

[0115] Table 2 Comparison of coating performance and application performance test results between Examples 1-3 and Comparative Examples 1-2

[0116]

[0117]

[0118] As shown in Table 2, compared with Comparative Examples 1-2, the test results of Examples 1-3 all meet the requirements. The coating is very lightweight, the film is dense and smooth, and the water absorption rate is low. It not only has excellent workability, excellent bonding strength and excellent stain resistance, but also has very good thermal insulation and weather resistance.

[0119] The technical content disclosed in this invention can be extensively extended. Other similar products, such as intermediate coatings and joint sealant, can be generated through simple substitutions and deductions, but these do not depart from the concept of this invention and do not constitute creative labor. Therefore, simple improvements and variations made to this invention by those skilled in the art based on its disclosure should be within the scope of protection of this invention. The above embodiments are preferred embodiments of this invention. All processes similar to this invention and equivalent changes should fall within the scope of protection of this invention.

Claims

1. A lightweight, high-efficiency thermal insulation coating, characterized in that, The lightweight, high-efficiency thermal insulation coating comprises a middle layer coating and a top layer coating, wherein: The topcoat coating comprises the following components by mass fraction: Pure acrylic emulsion 30-38% 8-12% acrylate monomers Modified silica 2-4% Titanium dioxide 20-25% Additives Initiator Water, remaining amount; The modified silica is obtained by grafting a mixture of unsaturated fatty acids onto silica; the content of the unsaturated fatty acids is 10-15 wt% of the total fatty acids. The preparation method of the lightweight, high-efficiency thermal insulation coating includes the following steps: S1. Hydroxylated silica is immersed in a solution of unsaturated fatty acids and saturated fatty acids, ultrasonically heated, and dried to obtain the modified silica. S2. The modified silica is blended with other components to obtain the topcoat coating; The pure acrylic emulsion is an emulsion based on acrylic polymer; The unsaturated fatty acid is selected from one or more of oleic acid, linoleic acid, or linolenic acid; The saturated fatty acid is selected from one or more of lauric acid, stearic acid, and palmitic acid.

2. The lightweight, high-efficiency thermal insulation coating according to claim 1, characterized in that, The acrylate monomer is selected from one or more of butyl acrylate, propyl acrylate, and ethyl acrylate.

3. The lightweight, high-efficiency thermal insulation coating according to claim 1, characterized in that, The additives are selected from one or more of the following: defoamers, adhesion promoters, thickeners, leveling agents, bactericides, dispersants, wetting agents, film-forming aids, aerogel dispersions, hollow glass microspheres, and cellulose.

4. The lightweight, high-efficiency thermal insulation coating according to claim 1, characterized in that, The titanium dioxide is selected from one or more of nuclear titanium dioxide and infrared reflective titanium dioxide.

5. The lightweight, high-efficiency thermal insulation coating according to claim 1, characterized in that, In step S1, the heating temperature is 70-80℃.

6. The application of a lightweight, high-efficiency thermal insulation coating, comprising applying the topcoat of any one of claims 1-5 onto the intermediate coating, and then photocuring.

Images