A light-heat curtain wall glass and a preparation method thereof

Abstract

The application relates to the technical field of glass coating, and discloses a light-heat curtain wall glass and a preparation method thereof. The light-heat curtain wall glass prepared by the application comprises a curtain wall glass substrate and a functional coating coated on the surface of the glass; wherein the functional coating is prepared by taking water-based polyurethane modified acrylic emulsion as main raw material and adding hydrophobic polyacrylate oligomer, hydrophobic silicon dioxide, functional fillers and other functional additives; after the functional coating is coated, the light-heat curtain wall glass can self-adapt to the temperature of four seasons, and the light-heat curtain wall glass is endowed with dynamic, efficient and stable light-heat conversion and heat management capabilities.

Description

Technical Field

[0001] This invention relates to the field of glass coating technology, specifically to a photothermal curtain wall glass and its preparation method. Background Technology

[0002] As a key innovation in modern building envelopes, the development of solar thermal curtain wall glass is rooted in the urgent need for building energy conservation and green sustainability. Traditional curtain wall glass primarily pursues transparency and aesthetics, but generally suffers from problems such as high light transmittance accompanied by high heat gain and rapid heat dissipation in winter, resulting in huge energy consumption for building cooling and heating. To overcome this bottleneck, early technologies such as heat-reflective glass, Low-E (low-emissivity) glass, and insulated / vacuum glass emerged. These technologies selectively reflect infrared rays through metal or oxide films or utilize inert gas interlayers to reduce heat conduction, thus achieving initial passive energy conservation. However, these static solutions cannot dynamically adapt to complex and changing climatic conditions and solar radiation. Their performance is limited during seasonal transitions or diurnal temperature variations, making it difficult to balance year-round energy efficiency and visual comfort.

[0003] Therefore, developing a new type of curtain wall glass that can actively respond to environmental changes and intelligently regulate photothermal behavior has become an important direction for the evolution of building energy-saving materials. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention provides a photothermal curtain wall glass and its preparation method.

[0005] The objective of this invention can be achieved through the following technical solutions: A photothermal curtain wall glass includes a curtain wall glass substrate and a functional coating applied to the surface of the curtain wall glass substrate; the curtain wall glass substrate is obtained by sequentially subjecting it to soapy water, acid washing, water washing and drying. The functional coating comprises the following raw materials in parts by weight: 20-30 parts of waterborne polyurethane modified acrylic emulsion, 6-12 parts of hydrophobic polyacrylate oligomer, 1-3 parts of hydrophobic silica, 4-8 parts of functional filler, 0.5-1 part of coupling agent, 8-15 parts of polyglycidyl methacrylate, 5-10 parts of isopropanol, and 100-150 parts of deionized water.

[0006] The coupling agent is one of the silane coupling agents KH-550, KH560 or KH570.

[0007] Furthermore, the hydrophobic polyacrylate oligomer is specifically prepared by the following steps: Fluorinated acrylate monomers, glycidyl methacrylate, ethyl acrylate, butyl methacrylate, and benzoyl peroxide are mixed and stirred evenly to form a premix. The reactor containing toluene is heated to 105°C, and the premix is ​​slowly added dropwise over a period of 2 hours. Then, a benzoyl peroxide toluene solution is added and the reaction is maintained at this temperature for 3-6 hours. The solvent is removed by vacuum distillation to obtain the hydrophobic polyacrylate oligomer.

[0008] Furthermore, the ratio of the above-mentioned fluorinated acrylate monomer, glycidyl methacrylate, ethyl acrylate, butyl methacrylate, benzoyl peroxide, toluene, and benzoyl peroxide toluene solution is 2.5-4.5g:3-5g:6-10g:4.5-6.5g:0.8-1.2g:50mL:10mL.

[0009] Furthermore, the ratio of benzoyl peroxide to toluene in the benzoyl peroxide toluene solution is 0.1-0.2 g: 10 mL.

[0010] Furthermore, the fluorinated acrylate monomer is one of dodecafluoroheptyl methacrylate, 1H,1H-perfluorooctyl acrylate, 1H,1H,2H,2H-perfluorooctyl acrylate, or perfluorooctyl ethyl acrylate.

[0011] The functional filler is prepared by the following steps: Step A1: Ti3AlC2 powder was stirred in 40wt% hydrofluoric acid at room temperature for 72h. The precipitate was collected and washed until neutral. The dried product was dispersed in dimethyl sulfone and stirred at room temperature for 18h. Then it was washed with water and ultrasonically treated in deionized water for 2h. After centrifugation and drying, the pretreated MXene powder was collected. The pretreated MXene powder was then ultrasonically dispersed in methanol, 30wt% H2O2 was added and stirred at room temperature for 1h. After centrifugation and drying, MXene nanosheets were obtained. Further, in step A1, the ratio of Ti3AlC2 powder, hydrofluoric acid, dimethyl sulfone, and deionized water used in the pretreatment of MXene powder is 1g:20mL:20mL:200mL. Furthermore, in step A1, the ratio of pretreated MXene powder, methanol, and H2O2 in the MXene nanosheets is 1g:100mL:13-16mL; Step A2: Mix oxalic acid in deionized water and stir until homogeneous. Then add vanadium pentoxide and mix thoroughly. Next, add MXene nanosheets and stir for 2 hours. Then transfer to a reaction vessel and hydrothermally react at 160-180℃ for 12-16 hours. Filter, wash, and dry to obtain VO2@MXene nanomaterials. Furthermore, in step A2, the ratio of oxalic acid, deionized water, vanadium pentoxide, and MXene nanosheets is 1.8-2.2 g: 50 mL: 1.2 g: 0.5 g; Step A3: Adjust the pH of the ethanol-water solution to 4.2-4.5, add KH-570 and stir for 2 hours to hydrolyze, then add VO2@MXene nanomaterials and stir evenly. Then heat to 60℃ and stir for 5 hours. Wash and dry to obtain grafted modified VO2@MXene nanomaterials. Then disperse the grafted modified VO2@MXene nanomaterials in deionized water, add isobutanol, adjust the pH of the system to 9.5, sonicate for 1 hour, add emulsifier OP-10 and stir for 12 hours. Then purge with nitrogen for 15 minutes, add sodium bicarbonate and potassium persulfate and stir evenly, then add methyl methacrylate and heat to 75℃ for 5-7 hours. Filter, wash and dry to obtain functional filler. Furthermore, in step A3, the ratio of ethanol aqueous solution, KH-570, and VO2@MXene nanomaterial in the grafted modified VO2@MXene nanomaterial is 100mL:0.05-0.1g:1g; Furthermore, in step A3, the volume ratio of ethanol to water in the ethanol aqueous solution of the grafted modified VO2@MXene nanomaterial is 9:1. Furthermore, in step A3, the ratio of grafted modified VO2@MXene nanomaterials, deionized water, isobutanol, emulsifier, sodium bicarbonate, potassium persulfate, and methyl methacrylate in the functional filler is 0.5g:100mL:4-8mL:0.2-0.5g:0.25-0.35g:0.03-0.04g:1.5-2.0g.

[0012] A method for preparing a photothermal curtain wall glass includes the following steps: Step S1: Clean the surface of the curtain wall glass substrate with soapy water, then soak it in a 10wt% hydrochloric acid solution for 30-60 minutes, then rinse the substrate surface with deionized water, rinse with distilled water, and dry to obtain the pretreated glass. Step S2: Weigh the raw materials according to the weight parts, mix the water-based polyurethane modified acrylic emulsion, hydrophobic polyacrylate oligomer, hydrophobic silica, functional filler, coupling agent, polyglycidyl methacrylate, isopropanol and deionized water evenly, and then spray it evenly on the pretreated glass surface and dry it to obtain the photothermal curtain wall glass.

[0013] The beneficial effects of this invention are: The photothermal curtain wall glass prepared by this invention includes a curtain wall glass substrate and a functional coating applied to the glass surface. The functional coating is made by using waterborne polyurethane modified acrylic emulsion as the main raw material, and adding hydrophobic polyacrylate oligomers, hydrophobic silica, functional fillers and other functional additives. After being coated with the functional coating, the photothermal curtain wall glass can adapt to the temperature of all four seasons, giving it dynamic, efficient and stable photothermal conversion and thermal management capabilities.

[0014] The functional filler introduced into the functional coating cleverly integrates the high conductivity and broad-spectrum absorption of MXene, the thermally induced intelligent phase transition of VO2, and the compatibility between the surface polyacrylate polymer and the base emulsion. MXene, acting as a highly efficient "light collector," possesses intrinsic broad-spectrum strong absorption capabilities in the visible and near-infrared portions of the solar spectrum due to its metallic conductivity and plasmon resonance effect. After absorbing photons, it efficiently converts energy into heat. Meanwhile, the loaded VO2 is in an insulating phase at low temperatures and is transparent to the mid- and far-infrared regions. At this time, the coating primarily contributes to the photothermal conversion through MXene, efficiently absorbing solar heat and conducting it into the room while reducing heat loss from the room, effectively increasing indoor temperature and reducing heating load. In high-temperature environments, when the coating absorbs solar radiation to near the VO2 phase transition point, VO2 transforms into a metallic phase, strongly absorbing and reflecting mid- and far-infrared rays. This not only further increases the capture of heat in the infrared portion of the sun but, more importantly, prevents indoor heat from escaping through the glass again in the form of infrared radiation, thus enhancing the thermal insulation effect. In addition, the polymer on the surface of the functional filler not only has good compatibility with the matrix, but also greatly reduces the interfacial thermal resistance between the functional filler and the polymer matrix by utilizing the covalent bonds formed by the surface polymer. This allows the heat generated by the nanoparticles to be efficiently and quickly transferred to the entire polymer coating, avoiding efficiency loss and material aging caused by heat accumulation at the interface.

[0015] In this invention, hydrophobic polyacrylate oligomers and hydrophobic silica are used as film-forming substances in the functional coating. This enables the coating to form a superhydrophobic surface and ensures that rainwater can automatically clean the surface dust, maintaining a high light absorption rate over a long period. At the same time, the dense coating and the filled silica work together to prevent external environmental erosion, ensuring the long lifespan of the coating under harsh outdoor conditions. Detailed Implementation

[0016] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] Example 1: Hydrophobic polyacrylate oligomer, specifically prepared by the following steps: 2.5g dodecafluoroheptyl methacrylate, 3g glycidyl methacrylate, 6g ethyl acrylate, 4.5g butyl methacrylate, and 0.8g benzoyl peroxide were mixed and stirred until homogeneous, and this mixture was recorded as a premix. A reactor containing 50mL of toluene was heated to 105℃, and the premix was slowly added dropwise over a period of 2 hours. Then, 10mL of benzoyl peroxide toluene solution was added and the reaction was maintained at this temperature for 3 hours. The solvent was removed by vacuum distillation to obtain the hydrophobic polyacrylate oligomer. The ratio of benzoyl peroxide to toluene in the benzoyl peroxide toluene solution was 0.1g:10mL.

[0018] The functional filler is prepared by the following steps: Step A1: 1g of Ti3AlC2 powder was stirred in 20mL of 40wt% hydrofluoric acid at room temperature for 72h. The precipitate was collected and washed until neutral. The dried product was dispersed in 20mL of dimethyl sulfone and stirred at room temperature for 18h. Then it was washed with water and ultrasonically treated in 200mL of deionized water for 2h. After centrifugation and drying, the pretreated MXene powder was collected. 1g of the pretreated MXene powder was then ultrasonically dispersed in 100mL of methanol. 13mL of 30wt% H2O2 was added and stirred at room temperature for 1h. After centrifugation and drying, MXene nanosheets were obtained. Step A2: Mix 1.8g of oxalic acid in 50mL of deionized water and stir until homogeneous. Then add 1.2g of vanadium pentoxide and mix thoroughly. Next, add 0.5g of MXene nanosheets and stir for 2 hours. Then transfer to a reaction vessel and hydrothermally react at 160℃ for 12 hours. Filter, wash and dry to obtain VO2@MXene nanomaterials. Step A3: Adjust the pH of 100 mL of ethanol-water solution (ethanol to water volume ratio of 9:1) to 4.2, add 0.05 g of KH-570 and stir for 2 h to hydrolyze, then add 1 g of VO2@MXene nanomaterial and stir evenly. Then heat to 60 °C and stir for 5 h. Wash and dry to obtain grafted modified VO2@MXene nanomaterial. Next, disperse 0.5 g of grafted modified VO2@MXene nanomaterial in 100 mL of deionized water, add 4 mL of isobutanol, adjust the pH of the system to 9.5, sonicate for 1 h, then add 0.2 g of emulsifier OP-10 and stir for 12 h. Then purge with nitrogen for 15 min, add 0.25 g of sodium bicarbonate and 0.03 g of potassium persulfate and stir evenly, then add 1.5 g of methyl methacrylate and heat to 75 °C for 5 h. Filter, wash and dry to obtain functional filler.

[0019] Example 2: Hydrophobic polyacrylate oligomers, specifically prepared by the following steps: 3.5g of dodecafluoroheptyl methacrylate, 4g of glycidyl methacrylate, 8g of ethyl acrylate, 5.5g of butyl methacrylate, and 1g of benzoyl peroxide were mixed and stirred until homogeneous, and this mixture was recorded as a premix. A reactor containing 50mL of toluene was heated to 105℃, and the premix was slowly added dropwise over a period of 2 hours. Then, 10mL of benzoyl peroxide toluene solution was added and the reaction was maintained at this temperature for 4.5 hours. The solvent was removed by vacuum distillation to obtain the hydrophobic polyacrylate oligomer. The ratio of benzoyl peroxide to toluene in the benzoyl peroxide toluene solution was 0.15g:10mL.

[0020] The functional filler is prepared by the following steps: Step A1: 1g of Ti3AlC2 powder was stirred in 20mL of 40wt% hydrofluoric acid at room temperature for 72h. The precipitate was collected and washed until neutral. The dried product was dispersed in 20mL of dimethyl sulfone and stirred at room temperature for 18h. Then it was washed with water and ultrasonically treated in 200mL of deionized water for 2h. After centrifugation and drying, the pretreated MXene powder was collected. 1g of the pretreated MXene powder was then ultrasonically dispersed in 100mL of methanol. 15mL of 30wt% H2O2 was added and stirred at room temperature for 1h. After centrifugation and drying, MXene nanosheets were obtained. Step A2: Mix 2g of oxalic acid in 50mL of deionized water and stir well. Then add 1.2g of vanadium pentoxide and mix thoroughly. Next, add 0.5g of MXene nanosheets and stir for 2h. Then transfer to a reaction vessel and hydrothermally react at 170℃ for 14h. Filter, wash and dry to obtain VO2@MXene nanomaterials. Step A3: Adjust the pH of 100 mL of ethanol-water solution (ethanol to water volume ratio of 9:1) to 4.3, add 0.075 g of KH-570 and stir for 2 h to hydrolyze, then add 1 g of VO2@MXene nanomaterial and stir evenly. Then heat to 60 °C and stir for 5 h. Wash and dry to obtain grafted modified VO2@MXene nanomaterial. Next, disperse 0.5 g of grafted modified VO2@MXene nanomaterial in 100 mL of deionized water, add 6 mL of isobutanol, adjust the pH of the system to 9.5, sonicate for 1 h, then add 0.35 g of emulsifier OP-10 and stir for 12 h. Then purge with nitrogen for 15 min, add 0.3 g of sodium bicarbonate and 0.035 g of potassium persulfate and stir evenly, then add 1.75 g of methyl methacrylate and heat to 75 °C for 6 h. Filter, wash and dry to obtain functional filler.

[0021] Example 3: Hydrophobic polyacrylate oligomers, specifically prepared by the following steps: 4.5g dodecafluoroheptyl methacrylate, 5g glycidyl methacrylate, 10g ethyl acrylate, 6.5g butyl methacrylate, and 1.2g benzoyl peroxide were mixed and stirred until homogeneous, and this mixture was recorded as a premix. A reactor containing 50mL of toluene was heated to 105℃, and the premix was slowly added dropwise over a period of 2 hours. Then, 10mL of benzoyl peroxide toluene solution was added and the reaction was maintained at this temperature for 6 hours. The solvent was removed by vacuum distillation to obtain the hydrophobic polyacrylate oligomer. The ratio of benzoyl peroxide to toluene in the benzoyl peroxide toluene solution was 0.2g:10mL.

[0022] The functional filler is prepared by the following steps: Step A1: 1g of Ti3AlC2 powder was stirred in 20mL of 40wt% hydrofluoric acid at room temperature for 72h. The precipitate was collected and washed until neutral. The dried product was dispersed in 20mL of dimethyl sulfone and stirred at room temperature for 18h. Then it was washed with water and ultrasonically treated in 200mL of deionized water for 2h. After centrifugation and drying, the pretreated MXene powder was collected. 1g of the pretreated MXene powder was then ultrasonically dispersed in 100mL of methanol. 16mL of 30wt% H2O2 was added and stirred at room temperature for 1h. After centrifugation and drying, MXene nanosheets were obtained. Step A2: Mix 2.2g of oxalic acid in 50mL of deionized water and stir until homogeneous. Then add 1.2g of vanadium pentoxide and mix thoroughly. Next, add 0.5g of MXene nanosheets and stir for 2 hours. Then transfer to a reaction vessel and hydrothermally react at 180℃ for 16 hours. Filter, wash and dry to obtain VO2@MXene nanomaterials. Step A3: Adjust the pH of 100 mL of ethanol-water solution (ethanol to water volume ratio of 9:1) to 4.5, add 0.1 g of KH-570 and stir for 2 h to hydrolyze, then add 1 g of VO2@MXene nanomaterial and stir evenly. Then heat to 60 °C and stir for 5 h. Wash and dry to obtain grafted modified VO2@MXene nanomaterial. Next, disperse 0.5 g of grafted modified VO2@MXene nanomaterial in 100 mL of deionized water, add 8 mL of isobutanol, and adjust the pH of the system to 9.5. Ultrasonically treat for 1 h, then add 0.5 g of emulsifier OP-10 and stir for 12 h. Then purge with nitrogen for 15 min, add 0.35 g of sodium bicarbonate and 0.04 g of potassium persulfate and stir evenly, then add 2.0 g of methyl methacrylate and heat to 75 °C for 7 h. Filter, wash and dry to obtain functional filler.

[0023] Example 4: A method for preparing a photothermal curtain wall glass includes the following steps: 20 parts of waterborne polyurethane modified acrylic emulsion, 6 parts of hydrophobic polyacrylate oligomer prepared in Example 1, 1 part of hydrophobic silica, 4 parts of functional filler prepared in Example 1, 0.5 parts of coupling agent KH-550, 8 parts of polyglycidyl methacrylate, 5 parts of isopropanol, and 100 parts of deionized water.

[0024] Step S1: Clean the surface of the curtain wall glass substrate with soapy water, then soak it in a 10wt% hydrochloric acid solution for 30 minutes, then rinse the substrate surface with deionized water, rinse with distilled water and dry to obtain the pretreated glass. Step S2: Weigh the raw materials according to the weight parts, mix and stir the waterborne polyurethane modified acrylic emulsion, the hydrophobic polyacrylate oligomer prepared in Example 1, the hydrophobic silica, the functional filler prepared in Example 1, the coupling agent KH-550, the polyglycidyl methacrylate, the isopropanol and deionized water evenly, and then spray it evenly on the pretreated glass surface and dry it to obtain the photothermal curtain wall glass.

[0025] Example 5: A method for preparing a photothermal curtain wall glass includes the following steps: 25 parts of waterborne polyurethane modified acrylic emulsion, 9 parts of hydrophobic polyacrylate oligomer prepared in Example 2, 2 parts of hydrophobic silica, 6 parts of functional filler prepared in Example 2, 0.75 parts of coupling agent KH560, 11 parts of polyglycidyl methacrylate, 7.5 parts of isopropanol, and 125 parts of deionized water.

[0026] Step S1: Clean the surface of the curtain wall glass substrate with soapy water, then soak it in a 10wt% hydrochloric acid solution for 45 minutes, then rinse the substrate surface with deionized water, rinse with distilled water and dry to obtain the pretreated glass. Step S2: Weigh the raw materials according to the weight parts, mix the waterborne polyurethane modified acrylic emulsion, the hydrophobic polyacrylate oligomer prepared in Example 2, the hydrophobic silica, the functional filler prepared in Example 2, the coupling agent KH560, the polyglycidyl methacrylate, the isopropanol and deionized water evenly, and then spray it evenly on the pretreated glass surface and dry it to obtain the photothermal curtain wall glass.

[0027] Example 6: A method for preparing a photothermal curtain wall glass includes the following steps: 30 parts of waterborne polyurethane modified acrylic emulsion, 12 parts of hydrophobic polyacrylate oligomer prepared in Example 3, 3 parts of hydrophobic silica, 8 parts of functional filler prepared in Example 3, 1 part of coupling agent KH570, 15 parts of polyglycidyl methacrylate, 10 parts of isopropanol, and 150 parts of deionized water.

[0028] Step S1: Clean the surface of the curtain wall glass substrate with soapy water, then soak it in a 10wt% hydrochloric acid solution for 60 minutes, then rinse the substrate surface with deionized water, rinse with distilled water, and dry to obtain the pretreated glass. Step S2: Weigh the raw materials according to the weight parts, mix and stir the water-based polyurethane modified acrylic emulsion, the hydrophobic polyacrylate oligomer prepared in Example 3, the hydrophobic silica, the functional filler prepared in Example 3, the coupling agent KH570, the polyglycidyl methacrylate, the isopropanol and deionized water evenly, and then spray it evenly on the pretreated glass surface and dry it to obtain the photothermal curtain wall glass.

[0029] Comparative Example 1: This comparative example is a photothermal curtain wall glass. The difference between this example and Example 6 is that the hydrophobic polyacrylate oligomer prepared in Example 3 was not added. All other aspects are the same.

[0030] Comparative Example 2: This comparative example is a photothermal curtain wall glass. The difference from Example 6 is that MXene nanosheets are used instead of the functional filler prepared in Example 3. All other aspects are the same.

[0031] Comparative Example 3: This comparative example is a photothermal curtain wall glass. The difference between this example and Example 6 is that vanadium dioxide is used instead of the functional filler prepared in Example 3.

[0032] The performance of the photothermal curtain wall glass prepared in Examples 4-6 and Comparative Examples 1-3 was tested, with a coating thickness of 5 μm. Adhesion test: According to GB / T 9286-2021 "Cross-cut test for paint and varnish film", the cross-cut test method is used to determine the adhesion grade of the paint film. Contact angle test: The water contact angle of the coating surface is tested using a contact angle meter; Photothermal performance testing: Using a UV-Vis-NIR spectrophotometer equipped with a temperature control device, the visible light transmittance T of the glass coating was tested at 20℃ and 90℃ respectively. lum Sunlight transmittance T sol ,in, T(λ) represents the transmittance at wavelength λ, and is the distribution curve of solar radiation wavelengths sensitive to human eye (380–780 nm). It represents the solar irradiance when the atmospheric mass (Air Mass, AM) is 1.5 and the sun is 37° above the horizon. The solar modulation capability (ΔT) is also relevant. sol ) by ΔT sol =T sol,20℃- T sol,90℃ The calculated values ​​are typically used to describe the performance of thermochromic smart glass.

[0033] The test results are shown in Table 1: Table 1: Performance Test Results As can be seen from Table 1, the functional coating on the surface of the photothermal curtain wall glass prepared by the present invention not only has high adhesion to the glass surface, but also endows the glass with excellent hydrophobic properties and good photothermal effect.

[0034] The above content is merely an example and illustration of the concept of the present invention. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the scope defined by the inventive concept, they should all fall within the protection scope of the present invention.

Claims

1. A photothermal curtain wall glass, characterized in that, It includes a curtain wall glass substrate and a functional coating applied to the surface of the curtain wall glass substrate; the curtain wall glass substrate is obtained by sequentially undergoing soaping, acid washing, water washing and drying. The functional coating comprises the following raw materials in parts by weight: 20-30 parts of waterborne polyurethane modified acrylic emulsion, 6-12 parts of hydrophobic polyacrylate oligomer, 1-3 parts of hydrophobic silica, 4-8 parts of functional filler, 0.5-1 part of coupling agent, 8-15 parts of polyglycidyl methacrylate, 5-10 parts of isopropanol, and 100-150 parts of deionized water. The functional filler is prepared by the polymerization reaction of KH-570 grafted VO2@MXene nanomaterial and methyl methacrylate. The VO2@MXene nanomaterial is prepared by loading VO2 after vanadium pentoxide reduction onto the surface of MXene nanosheets. The hydrophobic polyacrylate oligomer is prepared by the following steps: Fluorinated acrylate monomers, glycidyl methacrylate, ethyl acrylate, butyl methacrylate and benzoyl peroxide are mixed and stirred evenly, and this mixture is called the premix. The reactor containing toluene is heated to 105°C, and the premix is ​​slowly added dropwise, and the addition is completed within 2 hours. Then, benzoyl peroxide toluene solution is added and the reaction is kept at the temperature for 3-6 hours. The solvent is removed by vacuum distillation to obtain the hydrophobic polyacrylate oligomer. The functional filler is prepared by the following steps: Step A1: Ti3AlC2 powder was stirred in 40wt% hydrofluoric acid at room temperature for 72h, the precipitate was collected and washed until neutral, and the dried product was dispersed in dimethyl sulfone and stirred at room temperature for 18h, then washed with water, and then dispersed in deionized water and ultrasonically treated for 2h, centrifuged and dried to collect the pretreated MXene powder; the pretreated MXene powder was then ultrasonically dispersed in methanol, 30wt% H2O2 was added and stirred at room temperature for 1h, centrifuged and dried to obtain MXene nanosheets; Step A2: Mix oxalic acid in deionized water and stir until homogeneous. Then add vanadium pentoxide and mix thoroughly. Next, add MXene nanosheets and stir for 2 hours. Then transfer to a reaction vessel and hydrothermally react at 160-180℃ for 12-16 hours. Filter, wash, and dry to obtain VO2@MXene nanomaterials. Step A3: Adjust the pH of the ethanol-water solution to 4.2-4.5, add KH-570 and stir for 2 hours for hydrolysis, then add VO2@MXene nanomaterials and stir evenly. Subsequently, heat to 60℃ and stir for 5 hours. Wash and dry to obtain grafted modified VO2@MXene nanomaterials. Then disperse the grafted modified VO2@MXene nanomaterials in deionized water, add isobutanol, adjust the pH of the system to 9.5, sonicate for 1 hour, add emulsifier OP-10 and stir for 12 hours, then purge with nitrogen for 15 minutes, add sodium bicarbonate and potassium persulfate and stir evenly, then add methyl methacrylate and heat to 75℃ for 5-7 hours. Filter, wash and dry to obtain the functional filler.

2. A photothermal curtain wall glass according to claim 1, characterized in that, The ratio of the amount of the fluorinated acrylate monomer, glycidyl methacrylate, ethyl acrylate, butyl methacrylate, benzoyl peroxide, toluene, and benzoyl peroxide toluene solution is 2.5-4.5g:3-5g:6-10g:4.5-6.5g:0.8-1.2g:50mL:10mL.

3. The photothermal curtain wall glass according to claim 1, characterized in that, The ratio of benzoyl peroxide to toluene in the benzoyl peroxide to toluene solution is 0.1-0.2 g: 10 mL, and the fluorinated acrylate monomer is one of dodecafluoroheptyl methacrylate, 1H,1H-perfluorooctyl acrylate, 1H,1H,2H,2H-perfluorooctyl acrylate or perfluorooctyl ethyl acrylate.

4. The photothermal curtain wall glass according to claim 1, characterized in that, In step A1, the ratio of Ti3AlC2 powder, hydrofluoric acid, dimethyl sulfone, and deionized water in the pretreated MXene powder is 1g:20mL:20mL:200mL. The ratio of MXene powder, methanol, and H2O2 in the pretreated MXene nanosheets is 1g:100mL:13-16mL.

5. The photothermal curtain wall glass according to claim 1, characterized in that, In step A2, the ratio of oxalic acid, deionized water, vanadium pentoxide, and MXene nanosheets is 1.8-2.2g:50mL:1.2g:0.5g.

6. The photothermal curtain wall glass according to claim 1, characterized in that, In step A3, the ratio of ethanol aqueous solution, KH-570 and VO2@MXene nanomaterial in the grafted modified VO2@MXene nanomaterial is 100mL:0.05-0.1g:1g, and the volume ratio of ethanol to water in the ethanol aqueous solution is 9:

1.

7. The photothermal curtain wall glass according to claim 1, characterized in that, In step A3, the ratio of grafted modified VO2@MXene nanomaterials, deionized water, isobutanol, emulsifier, sodium bicarbonate, potassium persulfate, and methyl methacrylate in the functional filler is 0.5g:100mL:4-8mL:0.2-0.5g:0.25-0.35g:0.03-0.04g:1.5-2.0g.

8. A method for preparing the photothermal curtain wall glass according to any one of claims 1-7, characterized in that, Includes the following steps: Step S1: Clean the surface of the curtain wall glass substrate with soapy water, then soak it in a 10wt% hydrochloric acid solution for 30-60 minutes, then rinse the substrate surface with deionized water, rinse with distilled water, and dry to obtain the pretreated glass. Step S2: Weigh the raw materials according to the weight parts, mix the water-based polyurethane modified acrylic emulsion, hydrophobic polyacrylate oligomer, hydrophobic silica, functional filler, coupling agent, polyglycidyl methacrylate, isopropanol and deionized water evenly, and then spray it evenly on the pretreated glass surface and dry it to obtain the photothermal curtain wall glass.

Images