Preparation method of nano ceramic coating with infrared reflection and absorption functions

Abstract

The invention provides a preparation method of a nano ceramic coating with functions of reflecting and absorbing infrared rays. The preparation method comprises the following steps: firstly, preparing cesium tungsten bronze nano powder; then carrying out surface loading, washing and freeze drying on cesium tungsten bronze powder by adopting nano silver copper particles to prepare a composite heat insulation powder material, and grinding the composite heat insulation powder into semitransparent composite heat insulation slurry by using a dispersing agent, a wetting agent, ethanol and grinding resin; and finally, uniformly stirring and mixing the semitransparent composite heat insulation slurry, water-resistant silicon resin, an adhesion promoter, a wetting agent, a diluent and an ultraviolet absorbent to prepare the nano ceramic coating with infrared reflection and absorption functions. Clean glass is coated with the coating to prepare a coating, so that the glass has the characteristics of glare prevention, high heat dissipation, high heat insulation and the like, and has a wide application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of nano functional coating preparation, and in particular relates to a method for preparing a nano ceramic coating with both infrared reflection and absorption functions. Background Art

[0002] With global warming, the temperature difference between indoor and outdoor of heat-insulating glass can reach 5-15℃, which significantly improves human comfort. In summer, it can reduce the cooling capacity of air conditioners. Theoretically, the energy-saving efficiency can reach 20-35%. LOW-E glass is currently a commonly used building heat-insulating glass. LOW-E glass achieves heat insulation effect by coating on the surface of ordinary glass. The principle is to reduce the K value of glass. Although LOW-E glass has a good heat preservation and heat insulation effect on the building itself, it will reflect a large amount of sunlight and cause light pollution. If it is in a light-polluted environment for a long time, it will cause human vision to decline, and produce symptoms of dizziness, insomnia, palpitations, decreased appetite and depression. At the same time, LOW-E glass also has the problems of high cost, easy damage, and easy failure of offline LOW-E glass in 3-5 years. It is not suitable for all environments and difficult to maintain. In addition to LOW-E glass, transparent reflective coating products have also been developed, such as the silver-modified bismuth titanate light-reflective coating proposed in Chinese patent CN 113214740B, but it also has the problem of light pollution.

[0003] In recent years, glass thermal insulation coatings prepared with nano ATO or cesium tungsten bronze thermal insulation media have begun to receive widespread attention. For example, Chinese patent CN 102391778A proposes a colored transparent thermal insulation glass coating and its preparation method, which uses traditional ATO slurry as thermal insulation material to prepare thermal insulation glass coating; Chinese patent CN117625029A uses modified nano cesium tungsten bronze to prepare thermal insulation glass; however, using ATO or cesium tungsten bronze as thermal insulation medium mainly absorbs infrared sunlight to improve physical comfort, but the effect of reducing K value is not obvious, and the absorbed heat will accumulate on the glass surface. A large part of the heat will still be slowly transferred into the room, reducing energy saving efficiency. The traditional method is to use graphene and other materials with fast heat dissipation to assist heat dissipation, but the product formula requirements are extremely high. Graphene is very easy to precipitate, resulting in pitting on the coating surface, affecting the product experience.

[0004] Therefore, this patent provides a nano ceramic coating with both reflection and infrared absorption functions, combining the reflection effect of LOW-E glass with the heat absorption effect of cesium tungsten bronze, taking advantage of each other's strengths and making up for each other's weaknesses, and complementing each other's advantages. It not only solves the problems of high cost, easy damage, unsuitability for all environments, and difficult maintenance of LOW-E reflective glass, but also solves the problem of serious heat accumulation on the surface of infrared absorption coating, improves the K value, and greatly reduces light pollution compared to the total reflection coating. First, the present invention adopts a new material preparation process to solve the problem of stable loading of nano silver copper particles on cesium tungsten bronze powder. Synthesizing cesium tungsten bronze nanopowder is conducive to the loading of silver copper particles. At the same time, when synthesizing cesium tungsten bronze nanopowder, the complexing agent is directly combined with the powder, and then the silver copper ions are linked to the surface of cesium tungsten bronze through the complexing agent. Continue to reduce to obtain a stable silver-copper modified cesium tungsten bronze powder; the silver-copper modified cesium tungsten bronze powder is prepared into a dispersion and the preferred formula is made into a nano ceramic coating with both reflection and infrared absorption functions. Finally, the coating liquid is coated on the glass to prepare a coating with high heat insulation and high weather resistance. Compared with traditional glass heat insulation coatings that only have infrared absorption function, it has broad application prospects. Summary of the invention

[0005] The present invention provides a method for preparing a nano ceramic coating having both infrared reflection and absorption functions, and the specific steps are as follows:

[0006] 1. Preparation of cesium tungsten bronze nanopowder: First, weigh cesium iodide and ammonium metatungstate, add them to a certain mass of tetrasodium iminodisuccinate aqueous solution with a pH of 10, stir them ultrasonically for a certain time, add a reducing dispersant, continue to stir them ultrasonically for a certain time to obtain a precursor solution, transfer the precursor solution to a reactor, heat and keep it warm at a certain temperature for a certain time, cool it naturally, filter it, wash it clean, and obtain tungsten bronze insulation powder;

[0007] 2. Cesium tungsten bronze nanopowder loaded with nano silver-copper particles: In deionized water, cesium tungsten bronze powder is exfoliated and dispersed by ultrafine zirconium oxide beads at a low linear speed, and then soluble silver salt and soluble copper salt are added, stirred for a certain period of time, a reducing agent is added to react for a certain period of time, and freeze-dried to obtain silver-copper modified cesium tungsten bronze powder;

[0008] 3. Preparation of thermal insulation slurry: add dispersant, organic solvent and grinding resin to silver-copper modified cesium tungsten bronze nanopowder and grind it into translucent slurry;

[0009] 4. Finally, the heat-insulating slurry, water-resistant silicone resin, adhesion promoter, wetting agent, ultraviolet absorber, anti-glare slurry and diluent are stirred and mixed evenly, and sieved to make a nano-ceramic coating with both infrared reflection and absorption functions;

[0010] 5. Apply the prepared nano-ceramic coating with both infrared reflection and absorption functions to the clean glass surface under certain temperature and humidity requirements. After it is completely cured at room temperature, a high-efficiency heat-insulating glass coating can be obtained.

[0011] Preferably, the cesium tungsten bronze in the step is expressed as Cs X WO 3-δ , wherein 0.1<x≤0.3, δ represents oxygen vacancies; cesium iodide and ammonium metatungstate are used as main raw materials, wherein the molar ratio of Cs to W is (0.1-0.3):1; the total weight of cesium iodide and ammonium metatungstate, the tetrasodium iminodisuccinate aqueous solution with pH=10, and the mass ratio of the reducing dispersant is 1:3:0.1; the ultrasonic stirring time is 30-60 minutes; the reducing dispersant is polyvinyl pyrrolidone; the continued ultrasonic stirring time is 20-60 minutes; the heating temperature of the reactor is 160-280°C, and the heat preservation is 12-24 hours.

[0012] Preferably, in step 2), the soluble silver salt is silver nitrate, and the soluble copper salt is one of copper acetate, copper nitrate and copper sulfate; the reducing agent is ascorbic acid; the mass ratio of the cesium tungsten bronze powder, silver salt, copper salt and ascorbic acid is 100:(2-5):(2-5):5; the stirring time is 20-60 min; the zirconium beads are selected to have a diameter less than 0.1 mm, and the sanding linear speed is less than 10 m / s.

[0013] Preferably, in the step 3), the dispersant is one of Efka PX 5207 and Efka PX 4340; the grinding resin is one of aldehyde-ketone resin A81 and CT-120; the organic solvent is one of ethanol and propylene glycol methyl ether; the mass ratio of the silver-copper modified cesium tungsten bronze powder, the dispersant, the organic solvent and the grinding resin is 30:9:(50-80):3; the zirconium beads are selected to have a diameter of less than 0.1 mm, and the sanding linear speed is less than 12 m / s.

[0014] Preferably, the water-resistant silicone resin in step 4) is methyl-modified polynitrogen silane or fluorine-modified polynitrogen silane resin; the adhesion promoter is one of LT-1640 and Y-106; the wetting agent is one of Tego 245 and Tego 270; the ultraviolet absorber is one of UV-326 and UV-531; the diluent is one of PM and DPM or a combination thereof; the mass ratio of the thermal insulation slurry: water-resistant silicone resin: adhesion promoter: wetting agent: diluent and ultraviolet absorber = (10-30): 30: 0.5: 0.3: 30: (1-2).

[0015] Preferably, the construction temperature in step 5) is 18-40° C. and the humidity is less than 70%.

[0016] Compared with the prior art, the preparation method of the nano ceramic coating with both infrared reflection and absorption functions of the present invention has the following beneficial effects:

[0017] 1) Performance breakthrough: Through reflection-absorption synergy, wide-spectrum and efficient infrared blocking is achieved. Cesium tungsten bronze strongly absorbs in the near-infrared band of 900-1200nm, and nano-silver particles highly reflect in the mid-infrared band of 1200-2500nm. The two synergistic effects can expand the infrared blocking range from 780nm to 2500nm. The reflection function of silver reduces the heat accumulation absorbed by cesium tungsten bronze.

[0018] 2) Technological innovation: Complex anchoring technology solves the industry problem of easy aggregation and oxidation of nano silver. 6+ The reducing environment inhibits oxidation of silver.

[0019] 3) Application value: It has the characteristics of high light transmittance, low cost and easy maintenance, filling the market gap between Low-E glass and pure absorption coating. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0021] Figure 1 This is the SEM image of cesium tungsten bronze nanopowder in Example 1 of the present invention.

[0022] Figure 2 TEM image of silver-copper modified cesium tungsten bronze powder in Example 2 of the present invention

[0023] Figure 3 This is the particle size distribution diagram of the silver-copper modified cesium tungsten bronze dispersion of Example 4 of the present invention DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Embodiment 1

[0026] First, cesium tungsten bronze nanopowder is prepared: first, a mixture of cesium iodide and ammonium metatungstate with a total mass of 100g is weighed according to the molar ratio of cesium to tungsten in the molecular formula of 0.1:1, crushed and ground evenly, and then slowly added to 300g of tetrasodium iminodisuccinate aqueous solution with a pH of 10, ultrasonically stirred for 20min, and then 10g of polyvinyl pyrrolidone is added, and ultrasonic stirring is continued for 20min to obtain a precursor solution, and the precursor solution is transferred to a reactor and heated at 160°C for 12h, cooled naturally, filtered, and washed to obtain cesium tungsten bronze nanopowder;

[0027] Preparation of silver-copper modified cesium tungsten bronze powder: weigh 500g deionized water and 100g cesium tungsten bronze powder, use 0.05mm ultrafine zirconia beads and 8m / s low line speed to peel and disperse the tungsten bronze insulation powder, then add 2g silver nitrate and 2g copper acetate, stir for 20min, add ascorbic acid to react for 20min, and freeze-dry to obtain silver-copper modified cesium tungsten bronze powder.

[0028] Preparation of thermal insulation slurry: 30g of silver-copper modified cesium tungsten bronze powder was added with 9g of dispersant Efka PX 5207, 50g of ethanol, 3g of grinding resin A81, zirconium beads with a diameter of 0.05mm, and a sanding line speed of 11m / s to grind into a translucent slurry.

[0029] Finally, 10g of thermal insulation slurry, 30g of water-resistant methyl-modified polynitrogen silane, 0.5g of adhesion promoter LT-1640, 0.3g of wetting agent Tego 245, 1g of ultraviolet absorber UV-326, and 30g of diluent PM were stirred and mixed evenly, and sieved to make a nano-ceramic coating with both infrared reflection and absorption functions.

[0030] The nano ceramic coating with both infrared reflection and absorption functions is applied to a clean glass surface with a high-density sponge brush at 18° C. and 65% humidity to obtain a nano ceramic coating with both infrared reflection and absorption functions.

[0031] Embodiment 2

[0032] First, cesium tungsten bronze nanopowder is prepared: first, a mixture of cesium iodide and ammonium metatungstate with a total mass of 100g is weighed according to the molar ratio of cesium to tungsten in the molecular formula of 0.15:1, crushed and ground evenly, and then slowly added to 300g of tetrasodium iminodisuccinate aqueous solution with a pH of 10, ultrasonically stirred for 30min, and then 10g of polyvinyl pyrrolidone is added, and ultrasonic stirring is continued for 30min to obtain a precursor solution, and the precursor solution is transferred to a reactor and heated at 200°C for 16h, cooled naturally, filtered, and washed to obtain cesium tungsten bronze nanopowder;

[0033] Preparation of silver-copper modified cesium tungsten bronze powder: weigh 500g deionized water and 100g cesium tungsten bronze powder, use 0.03mm ultrafine zirconia beads at a low linear speed of 6m / s to peel and disperse the tungsten bronze insulation powder, then add 3g silver nitrate and 3g copper nitrate, stir for 30min, add ascorbic acid to react for 30min, and freeze-dry to obtain silver-copper modified cesium tungsten bronze powder.

[0034] Preparation of thermal insulation slurry: 30g of silver-copper modified cesium tungsten bronze powder, 9g of dispersant Efka PX 4340, 60g of propylene glycol methyl ether, 3g of grinding resin CT-120, zirconium beads with a diameter of 0.0.03mm, sanding line speed less than 10m / s, grind into a translucent slurry.

[0035] Finally, 15g of the thermal insulation slurry, 30g of the water-resistant fluorine-modified polynitrogen silane resin, 0.5g of the adhesion promoter Y-106, 0.3g of the wetting agent Tego 270, 1.2g of the ultraviolet absorber UV-531, and 30g of the diluent DPM were stirred and mixed evenly, and sieved to make a nano-ceramic coating with both infrared reflection and absorption functions.

[0036] The nano ceramic coating with both infrared reflection and absorption functions is applied to the clean glass surface with a high-density sponge brush at 25° C. and 60% humidity to obtain the nano ceramic coating with both infrared reflection and absorption functions.

[0037] Embodiment 3

[0038] First, cesium tungsten bronze nanopowder is prepared: first, a mixture of cesium iodide and ammonium metatungstate with a total mass of 100g is weighed according to the molar ratio of cesium to tungsten in the molecular formula of 0.3:1, crushed and ground evenly, and then slowly added to 300g of tetrasodium iminodisuccinate aqueous solution with a pH of 10, ultrasonically stirred for 50min, and then 10g of polyvinyl pyrrolidone is added, and ultrasonic stirring is continued for 50min to obtain a precursor solution, and the precursor solution is transferred to a reactor and heated at 250°C for 19h, cooled naturally, filtered, and washed to obtain cesium tungsten bronze nanopowder;

[0039] Preparation of silver-copper modified cesium tungsten bronze powder: weigh 500g deionized water and 100g cesium tungsten bronze powder, use 0.05mm ultrafine zirconia beads and 8m / s low line speed to peel and disperse the tungsten bronze insulation powder, then add 4g silver nitrate and 4g copper sulfate, stir for 50min, add ascorbic acid to react for 50min, and freeze-dry to obtain silver-copper modified cesium tungsten bronze powder.

[0040] Preparation of thermal insulation slurry: 30g of silver-copper modified cesium tungsten bronze powder was added with 9g of dispersant Efka PX 5207, 70g of ethanol, 3g of grinding resin A81, zirconium beads with a diameter of 0.03mm, and a sand milling line speed of 9m / s to grind into a translucent slurry.

[0041] Finally, 20g of thermal insulation slurry, 30g of water-resistant methyl-modified polynitrogen silane, 0.5g of adhesion promoter LT-1640, 0.3g of wetting agent Tego 245, 1.6g of ultraviolet absorber UV-326, and 30g of diluent PM were stirred and mixed evenly, and sieved to make a nano-ceramic coating with both infrared reflection and absorption functions.

[0042] The nano ceramic coating with both infrared reflection and absorption functions is applied to the clean glass surface with a high-density sponge brush at 30° C. and 40% humidity to obtain the nano ceramic coating with both infrared reflection and absorption functions.

[0043] Embodiment 4

[0044] First, cesium tungsten bronze nanopowder is prepared: first, a mixture of cesium iodide and ammonium metatungstate with a total mass of 100g is weighed according to the molar ratio of cesium to tungsten in the molecular formula of 0.3:1, crushed and ground evenly, and then slowly added to 300g of tetrasodium iminodisuccinate aqueous solution with a pH of 10, ultrasonically stirred for 60min, and then 10g of polyvinyl pyrrolidone is added, and ultrasonic stirring is continued for 60min to obtain a precursor solution, and the precursor solution is transferred to a reactor and heated at 280°C for 24h, cooled naturally, filtered, and washed to obtain cesium tungsten bronze nanopowder;

[0045] Preparation of silver-copper modified cesium tungsten bronze powder: weigh 500g deionized water and 100g cesium tungsten bronze powder, use ultrafine zirconium oxide beads less than 0.03mm and a low linear speed of 9m / s to peel and disperse the tungsten bronze insulation powder, then add 5g silver nitrate and 5g copper acetate, stir for 20-60min, add ascorbic acid to react for 60min, and freeze-dry to obtain silver-copper modified cesium tungsten bronze powder.

[0046] Preparation of thermal insulation slurry: 30g of silver-copper modified cesium tungsten bronze powder was added to 9g of dispersant Efka PX 4340, 80g of propylene glycol methyl ether, 3g of grinding resin CT-120, zirconium beads with a diameter of 0.03mm, and a sanding line speed of less than 6m / s to grind into a translucent slurry.

[0047] Finally, 30g of thermal insulation slurry, 30g of water-resistant fluorine-modified polynitrogen silane resin, 0.5g of adhesion promoter Y-106, 0.3g of wetting agent Tego 270, 2g of ultraviolet absorber UV-531, and 30g of diluent DPM were stirred and mixed evenly, and sieved to make a nano-ceramic coating with both infrared reflection and absorption functions.

[0048] The nano ceramic coating with both infrared reflection and absorption functions is applied to a clean glass surface with a high-density sponge brush at 40° C. and 10% humidity to obtain a nano ceramic coating with both infrared reflection and absorption functions.

[0049] Comparative Example 1

[0050] The difference from Example 1 is that commercially available cesium tungsten bronze powder (Shanghai Huben) is used to prepare a coating in the manner of Comparative Example 1, and the performance is tested.

[0051] Comparative Example 2

[0052] Commercially available cesium tungsten bronze powder, manufactured by Shanghai Huzheng, was used to prepare a coating in the manner of Comparative Example 1, and the performance was tested.

[0053] The performance of Examples 1-4 of the present application and Comparative Examples 1-2 were tested.

[0054] Infrared blocking rate: tested using LS182 solar film tester

[0055] UV absorption rate: tested using LS182 solar film tester

[0056] Total solar transmittance ratio: tested using LS182 solar film tester

[0057] Table 1 shows the coating performance parameters of Example 1, Example 2, Example 3, Example 4, Comparative Example 1 and Comparative Example 2

[0058] hardness Adhesion UV Absorption Infrared blocking rate Total solar transmittance Embodiment 1 5H Level 0 99.9％ 90％ 0.380 Embodiment 2 5H Level 0 99.9％ 92％ 0.375 Embodiment 3 5H Level 0 99.9％ 93％ 0.355 Embodiment 4 5H Level 0 99.9％ 95％ 0.344 Comparative Example 1 5H Level 0 99.9％ 82％ 0.46 Comparative Example 2 5H Level 0 99.9％ 85％ 0.44

[0059] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. The present invention provides a method for preparing a nano ceramic coating having both infrared reflection and absorption functions, characterized in that: The specific steps are as follows: 1) Preparation of cesium tungsten bronze nanopowder: First, weigh cesium iodide and ammonium metatungstate, add them to a certain mass of tetrasodium iminodisuccinate aqueous solution with a pH of 10, stir ultrasonically for a certain time, add a reducing dispersant, continue ultrasonic stirring for a certain time to obtain a precursor solution, transfer the precursor solution to a reactor, heat and keep it warm at a certain temperature for a certain time, cool naturally, filter, wash and clean to obtain tungsten bronze insulation powder; 2) Cesium tungsten bronze nanopowder loaded with nano silver-copper particles: In deionized water, cesium tungsten bronze nanopowder is exfoliated and dispersed by ultrafine zirconium oxide beads at a low linear speed, and then soluble silver salt and soluble copper salt are added, stirred for a certain period of time, a reducing agent is added to react for a certain period of time, and freeze-dried to obtain silver-copper modified cesium tungsten bronze powder; 3) Preparation of thermal insulation slurry: Add dispersant, organic solvent and grinding resin to silver-copper modified cesium tungsten bronze nanopowder and grind it into a translucent slurry; 4) Finally, the heat-insulating slurry, water-resistant silicone resin, adhesion promoter, wetting agent, ultraviolet absorber, anti-glare slurry and diluent are stirred and mixed evenly, and sieved to prepare a nano-ceramic coating with both infrared reflection and absorption functions; 5) The prepared nano-ceramic coating with both infrared reflection and absorption functions is applied to the clean glass surface under certain temperature and humidity requirements. After being completely cured at room temperature, a nano-ceramic coating with both infrared reflection and absorption functions can be obtained.

2. The method for preparing a nano ceramic coating having both infrared reflection and absorption functions according to claim 1, characterized in that: In step 1), the cesium tungsten bronze is expressed as Cs X WO 3-δ , wherein 0.1<x≤0.3, δ represents oxygen vacancies; cesium iodide and ammonium metatungstate are used as main raw materials, wherein the molar ratio of Cs to W is (0.1-0.3):1; the total weight of cesium iodide and ammonium metatungstate, the tetrasodium iminodisuccinate aqueous solution with pH=10, and the mass ratio of the reducing dispersant is 1:3:0.1; the ultrasonic stirring time is 30-60 minutes; the reducing dispersant is polyvinyl pyrrolidone; the continued ultrasonic stirring time is 20-60 minutes; the heating temperature of the reactor is 160-280°C, and the heat preservation is 12-24 hours.

3. The method for preparing a nano ceramic coating having both infrared reflection and absorption functions according to claim 1, characterized in that: In the step 2), the soluble silver salt is silver nitrate, and the soluble copper salt is one of copper acetate, copper nitrate and copper sulfate; the reducing agent is ascorbic acid; the mass ratio of the cesium tungsten bronze powder, silver salt, copper salt and ascorbic acid is 100: (2-5): (2-5): 5; the stirring time is 20 to 60 minutes; the zirconium beads are selected to have a diameter less than 0.1 mm, and the sanding line speed is less than 10 m / s.

4. The method for preparing a nano ceramic coating having both infrared reflection and absorption functions according to claim 1, characterized in that: In the step 3), the dispersant is one of EfkaPX 5207 and EfkaPX 4340; the grinding resin is one of aldehyde-ketone resin A81 and CT-120; the organic solvent is one of ethanol and propylene glycol methyl ether; the mass ratio of the silver-copper modified cesium tungsten bronze powder, the dispersant, the organic solvent and the grinding resin is 30:9:(50-80):3; the zirconium beads are selected to have a diameter less than 0.1 mm, and the sanding linear speed is less than 12 m / s.

5. The method for preparing a nano ceramic coating having both infrared reflection and absorption functions according to claim 1, characterized in that: In step 4), the water-resistant silicone resin is methyl-modified polynitrogen silane or fluorine-modified polynitrogen silane resin; the adhesion promoter is one of LT-1640 and Y-106; the wetting agent is one of Tego 245 and Tego 270; the ultraviolet absorber is one of UV-326 and UV-531; the diluent is one of PM and DPM or a combination thereof; the mass ratio of the thermal insulation slurry: water-resistant silicone resin: adhesion promoter: wetting agent: diluent and ultraviolet absorber is (10~30): 30: 0.5: 0.3: 30: (1~2).

6. The method for preparing a nano ceramic coating having both infrared reflection and absorption functions according to claim 1, characterized in that: The construction temperature of step 5) is 18-40° C. and the humidity is less than 70%.

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