Intelligent dimming glass and preparation method thereof

Abstract

The application relates to the technical field of glass, and particularly provides a kind of intelligent light-adjusting glass and a preparation method thereof.The intelligent light-adjusting glass comprises glass and a film layer covering the surface of the glass.The film layer comprises the following raw materials by weight: ammonia plasma modified samarium-doped VO2 0.15-0.25 parts, silane coupling agent modified glass beads 0.5-0.7 parts, film-forming high molecular polymer 4.5-6 parts, and solvent 20-25 parts.The application can reduce the phase transition temperature, and the obtained intelligent light-adjusting glass has high sunlight modulation capacity and high visible light transmittance.

Description

Technical Field

[0001] This invention relates to the field of glass technology, specifically to a smart dimming glass and its preparation method. Background Technology

[0002] Smart dimming glass can intelligently adjust the absorption of solar energy according to the ambient temperature. Specifically, it has high transmittance of sunlight (mainly in the near-infrared region) at low temperatures and low transmittance at high temperatures, thereby achieving the purpose of smart dimming.

[0003] At low temperatures (M phase), VO2 allows for good transmission of both near-infrared and visible light from sunlight, while at high temperatures (R phase), it effectively blocks near-infrared light but still maintains high transmittance for visible light. This phase transition characteristic gives VO2 excellent sunlight modulation capabilities, making it an ideal material for manufacturing smart dimming glass. Therefore, preparing VO2 as a coating and forming a VO2 smart coating on glass can easily transform existing ordinary glass into smart glass. However, the phase transition stability of VO2 (M phase) is currently relatively poor, and its ability to modulate sunlight is not high enough. Therefore, further research is needed on materials for VO2 smart coatings to obtain smart dimming glass with even better dimming performance. Summary of the Invention

[0004] The purpose of this invention is to provide a smart dimming glass and its preparation method, which, while reducing the phase transition temperature, produces a smart dimming glass with both high solar light modulation capability and high visible light transmittance.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A smart dimming glass includes glass and a thin film layer coated on the surface of the glass;

[0007] The thin film layer comprises the following raw materials in parts by weight: 0.15-0.25 parts of ammonia plasma-modified samarium-doped VO2, 0.5-0.7 parts of silane coupling agent-modified glass microspheres, 4.5-6 parts of film-forming polymer, and 20-25 parts of solvent.

[0008] Preferably, the method for preparing ammonia plasma-modified samarium-doped VO2 includes the following steps:

[0009] (1) A hydrothermal reaction was carried out using a mixed system containing vanadium oxalate, urea, samarium nitrate and water. The intermediate solid product obtained after the treatment was then annealed under an argon atmosphere to obtain samarium-doped VO2.

[0010] (2) Samarium-doped VO2 was placed in a low-temperature plasma reactor and modified with ammonia.

[0011] Preferably, step (1) specifically includes the following steps: adding 1.5-2 parts of vanadium pentoxide and oxalic acid dihydrate to 100 parts of water, wherein the molar ratio of vanadium pentoxide to oxalic acid dihydrate is 1:2.99-3.01; then heating to 70-75℃ and stirring for 3-5 hours to obtain a vanadium oxalate precursor solution; then adding 0.7-1.1 parts of urea and 0.1-0.12 parts of samarium nitrate to the vanadium oxalate precursor solution, stirring and mixing, and then placing it at 180-190℃ for hydrothermal reaction for 56-72 hours; then annealing the intermediate solid product obtained after treatment under an argon atmosphere at a temperature of 750-780℃ for 7-8 hours to obtain samarium-doped VO2.

[0012] Preferably, in step (1), the specific processing includes the following steps: allowing the reaction mixture after hydrothermal reaction to stand, then removing the supernatant, centrifuging, washing with water and anhydrous ethanol in sequence, and drying to obtain an intermediate solid product.

[0013] Preferably, in step (2), when ammonia is used for modification treatment, the treatment time is 10-30 min, the treatment voltage is 1-3 KV, and the treatment current is 0.5-1.5 A.

[0014] Preferably, the film-forming polymer is one or more of polyvinyl alcohol formaldehyde, polyvinyl alcohol acetal, and polyvinyl alcohol butyral; the molecular weight of the film-forming polymer is 80,000-100,000.

[0015] Preferably, the solvent is N,N-dimethylformamide or N,N-dimethylacetamide.

[0016] Preferably, the preparation method of the silane coupling agent modified glass microspheres includes the following steps: mixing glass microspheres with 0.8-1.1% of its mass of silane coupling agent for 60-90 min to obtain the glass microspheres; the particle size of the glass microspheres is 10-50 μm; and the silane coupling agent is KH560 or KH570.

[0017] Preferably, the glass microspheres have a particle size of 25-30 μm.

[0018] As a general inventive concept, this invention provides a method for preparing smart dimming glass, comprising the following steps:

[0019] S1: Clean and dry the glass;

[0020] S2: Weigh each raw material for preparing the thin film layer; add the film-forming polymer to the solvent, stir and mix to dissolve, then add other raw materials for mixing, and prepare the coating mixture after vacuum degassing; uniformly coat the coating mixture onto the glass surface treated in step S1, and prepare the smart dimming glass after drying and curing.

[0021] Preferably, step S1 specifically includes the following steps: first, ultrasonically clean the glass with a cleaning solution for 8-10 minutes, then ultrasonically clean it with acetone and ethanol solutions for 8-10 minutes in sequence, then ultrasonically clean it with deionized water for 8-10 minutes, and finally dry the glass surface with nitrogen gas for later use.

[0022] The beneficial effects of this invention are:

[0023] In this invention, a suitable amount of samarium is doped into the VO2 used to prepare the thin film layer. Studies have shown that samarium doping does not damage the structure of VO2; instead, it refines the grain size and lowers the phase transition temperature. Specifically, the phase transition temperature of the samarium-doped VO2 can be reduced from nearly 68°C to approximately 62°C, exhibiting good optical properties and phase transition stability. Furthermore, after ammonia plasma modification, the phase transition temperature of the samarium-doped VO2 is further significantly reduced, reaching approximately 53°C. Using this invention to prepare the thin film layer with ammonia plasma-modified samarium-doped VO2 results in a lower overall phase transition temperature for smart dimming glass, and a significantly improved solar light modulation capability.

[0024] The ammonia plasma-modified samarium-doped VO2 preparation not only has a lower phase transition temperature, but also significantly improved dispersibility compared to unmodified VO2. When combined with glass microspheres of suitable particle size, it can enable smart dimming glass to maintain a high visible light transmittance.

[0025] The thin film layer of this invention, applied to the glass surface, uses suitable raw materials to reduce the phase transition temperature, thereby enabling the final smart dimming glass to possess both high solar light modulation capability and high visible light transmittance. Detailed Implementation

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, 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.

[0027] Example 1:

[0028] A smart dimming glass includes glass and a thin film layer coated on the surface of the glass; the thin film layer includes the following raw materials in parts by weight: 0.2 parts of ammonia plasma modified samarium doped VO2, 0.55 parts of silane coupling agent modified glass microspheres, 5 parts of polyvinyl acetal (molecular weight of 100,000), and 25 parts of N,N-dimethylformamide.

[0029] The preparation method of ammonia plasma-modified samarium-doped VO2 includes the following steps:

[0030] (1) Add 1.5 parts of vanadium pentoxide and oxalic acid dihydrate to 100 parts of water, with a molar ratio of vanadium pentoxide to oxalic acid dihydrate of 1:3; then heat to 75℃ and stir for 3 hours to obtain a vanadium oxalate precursor solution; then add 1 part of urea and 0.12 parts of samarium nitrate to the vanadium oxalate precursor solution, stir and mix, and then place at 185℃ for hydrothermal reaction for 72 hours;

[0031] After hydrothermal reaction, the reaction mixture was allowed to stand, then the supernatant was removed, centrifuged, and washed with water and anhydrous ethanol in sequence. After drying, the intermediate solid product was obtained.

[0032] The intermediate solid product was then annealed in an argon atmosphere at a temperature of 750°C for 8 hours to obtain samarium-doped VO2.

[0033] (2) Samarium-doped VO2 was placed in a low-temperature plasma reactor and modified with ammonia gas for 20 min, 2 kV, and 1 A.

[0034] The preparation method of silane coupling agent modified glass microspheres includes the following steps: mixing glass microspheres with a particle size of 25-30μm with 0.8% by mass of silane coupling agent KH570 for 90min to obtain the product.

[0035] The preparation method of the above-mentioned smart dimming glass includes the following steps:

[0036] S1: First, ultrasonically clean the glass with a cleaning solution for 10 minutes, then ultrasonically clean it with acetone and ethanol solutions for 8 minutes in sequence, then ultrasonically clean it with deionized water for 10 minutes, and finally dry the glass surface with nitrogen gas for later use.

[0037] S2: Weigh the raw materials for preparing the thin film layer; add polyvinyl alcohol acetal to N,N-dimethylformamide, stir and mix to dissolve, then add other raw materials and mix, and prepare the coating mixture after vacuum degassing; coat the coating mixture evenly on the glass surface treated in step S1, and prepare the smart dimming glass after drying and curing.

[0038] Example 2:

[0039] A smart dimming glass includes glass and a thin film layer coated on the surface of the glass; the thin film layer includes the following raw materials in parts by weight: 0.15 parts of ammonia plasma modified samarium doped VO2, 0.7 parts of silane coupling agent modified glass microspheres, 6 parts of polyvinyl formal (molecular weight of 80,000), and 23 parts of N,N-dimethylformamide.

[0040] The preparation method of ammonia plasma-modified samarium-doped VO2 includes the following steps:

[0041] (1) Add 1.8 parts of vanadium pentoxide and oxalic acid dihydrate to 100 parts of water, with a molar ratio of vanadium pentoxide to oxalic acid dihydrate of 1:2.99; then heat to 70℃ and stir for 5h to obtain a vanadium oxalate precursor solution; then add 0.7 parts of urea and 0.1 parts of samarium nitrate to the vanadium oxalate precursor solution, stir and mix, and then place at 180℃ for hydrothermal reaction for 56h.

[0042] After hydrothermal reaction, the reaction mixture was allowed to stand, then the supernatant was removed, centrifuged, and washed with water and anhydrous ethanol in sequence. After drying, the intermediate solid product was obtained.

[0043] The intermediate solid product was then annealed in an argon atmosphere at a temperature of 780°C for 7.5 hours to obtain samarium-doped VO2.

[0044] (2) Samarium-doped VO2 was placed in a low-temperature plasma reactor and modified with ammonia gas for 30 min, 1 kV, and 1.5 A.

[0045] The preparation method of silane coupling agent modified glass microspheres includes the following steps: mixing glass microspheres with a particle size of 25-30μm with 1% by mass of silane coupling agent KH560 for 60min to obtain the product.

[0046] The preparation method of the above-mentioned smart dimming glass includes the following steps:

[0047] S1: First, ultrasonically clean the glass with a cleaning solution for 8 minutes, then ultrasonically clean it with acetone and ethanol solutions for 10 minutes in sequence, then ultrasonically clean it with deionized water for 8 minutes, and finally dry the glass surface with nitrogen gas for later use.

[0048] S2: Weigh the raw materials for preparing the thin film layer; add polyvinyl alcohol formaldehyde to N,N-dimethylformamide, stir and mix to dissolve, then add other raw materials and mix, and prepare the coating mixture after vacuum degassing; coat the coating mixture evenly on the glass surface treated in step S1, and prepare the smart dimming glass after drying and curing.

[0049] Example 3:

[0050] A smart dimming glass includes glass and a thin film layer coated on the surface of the glass; the thin film layer includes the following raw materials in parts by weight: 0.25 parts of ammonia plasma modified samarium doped VO2, 0.5 parts of silane coupling agent modified glass microspheres, 4.5 parts of polyvinyl butyral (molecular weight of 100,000), and 20 parts of N,N-dimethylacetamide.

[0051] The preparation method of ammonia plasma-modified samarium-doped VO2 includes the following steps:

[0052] (1) Add 2 parts of vanadium pentoxide and oxalic acid dihydrate to 100 parts of water, with a molar ratio of vanadium pentoxide to oxalic acid dihydrate of 1:3.01; then heat to 72℃ and stir for 4 hours to obtain a vanadium oxalate precursor solution; then add 1.1 parts of urea and 0.12 parts of samarium nitrate to the vanadium oxalate precursor solution, stir and mix, and then place at 190℃ for hydrothermal reaction for 64 hours;

[0053] After hydrothermal reaction, the reaction mixture was allowed to stand, then the supernatant was removed, centrifuged, and washed with water and anhydrous ethanol in sequence. After drying, the intermediate solid product was obtained.

[0054] The intermediate solid product was then annealed in an argon atmosphere at a temperature of 760°C for 7 hours to obtain samarium-doped VO2.

[0055] (2) Samarium-doped VO2 was placed in a low-temperature plasma reactor and modified with ammonia gas for 10-30 min, 3 kV, and 1.5 A.

[0056] The preparation method of silane coupling agent modified glass microspheres includes the following steps: mixing glass microspheres with a particle size of 25-30μm with 1.1% by mass of silane coupling agent KH570 for 70min to obtain the product.

[0057] The preparation method of the above-mentioned smart dimming glass includes the following steps:

[0058] S1: First, ultrasonically clean the glass with a cleaning solution for 10 minutes, then ultrasonically clean it with acetone and ethanol solutions for 10 minutes in sequence, then ultrasonically clean it with deionized water for 10 minutes, and finally dry the glass surface with nitrogen gas for later use.

[0059] S2: Weigh the raw materials for preparing the thin film layer; add polyvinyl butyral to N,N-dimethylacetamide, stir and mix to dissolve, then add other raw materials and mix, and prepare the coating mixture after vacuum degassing; coat the coating mixture evenly on the glass surface treated in step S1, and prepare the smart dimming glass after drying and curing.

[0060] Example 4:

[0061] A smart dimming glass includes glass and a thin film layer coated on the surface of the glass; the thin film layer includes the following raw materials in parts by weight: 0.18 parts of ammonia plasma modified samarium doped VO2, 0.55 parts of silane coupling agent modified glass microspheres, 5.5 parts of polyvinyl acetal (molecular weight of 100,000), and 25 parts of N,N-dimethylformamide.

[0062] The preparation method of ammonia plasma-modified samarium-doped VO2 is the same as in Example 1. The preparation method of silane coupling agent-modified glass microspheres is the same as in Example 1.

[0063] The preparation method of the smart dimming glass is the same as in Example 1.

[0064] Example 5:

[0065] Unlike Example 1, the glass microspheres in the silane coupling agent modified glass microspheres have a particle size of 10-15 μm.

[0066] Example 6:

[0067] Unlike Example 1, the glass microspheres in the silane coupling agent modified glass microspheres have a particle size of 45-50 μm.

[0068] Comparative Example 1:

[0069] Unlike Example 1, ammonia plasma-modified samarium-doped VO2 was replaced with VO2. The preparation method of VO2 included the following steps: adding 1.5 parts of vanadium pentoxide and oxalic acid dihydrate to 100 parts of water, with a molar ratio of vanadium pentoxide to oxalic acid dihydrate of 1:3; then heating to 75°C and stirring for 3 hours to obtain a vanadium oxalate precursor solution; then adding 1 part of urea to the vanadium oxalate precursor solution, stirring and mixing, and then placing it at 185°C for hydrothermal reaction for 72 hours.

[0070] After hydrothermal reaction, the reaction mixture was allowed to stand, then the supernatant was removed, centrifuged, and washed with water and anhydrous ethanol in sequence. After drying, the intermediate solid product was obtained.

[0071] The intermediate solid product was then annealed in an argon atmosphere at a temperature of 750°C for 8 hours to obtain samarium-doped VO2.

[0072] The visible light transmittance and solar energy regulation capability of the smart dimming glass prepared in Examples 1-6 and Comparative Example 1 are shown in Table 1, wherein the thickness of the thin film layer is 0.2±1mm.

[0073] Table 1. Visible light transmittance and solar energy regulation capability of smart dimming glass.

[0074] Example 1 45.3 13.2 Example 2 46.1 12.7 Example 3 43.2 14.3 Example 4 45.7 12.9 Example 5 44.2 12.6 Example 6 44.5 12.4 Comparative Example 1 42.9 10.6

[0075] As shown in Table 1, the smart dimming glass prepared in the embodiments of the present invention possesses both high solar light modulation capability and high visible light transmittance. A comparison between Examples 1 and Examples 5-6 shows that when the particle size of the glass microspheres is 25-30 μm, its combination with ammonia plasma-modified samarium-doped VO2 further enhances the visible light transmittance and solar light modulation capability of the smart dimming glass. A comparison between Example 1 and Comparative Example 1 shows that samarium doping and ammonia plasma modification of VO2 significantly improve both solar light modulation capability and visible light transmittance.

[0076] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A smart dimming glass, characterized in that, Including glass and the thin film layer covering the glass surface; The thin film layer comprises the following raw materials in parts by weight: 0.15-0.25 parts of ammonia plasma-modified samarium-doped VO2, 0.5-0.7 parts of silane coupling agent-modified glass microspheres, 4.5-6 parts of film-forming polymer, and 20-25 parts of solvent.

2. The smart dimming glass according to claim 1, characterized in that, The method for preparing ammonia plasma-modified samarium-doped VO2 includes the following steps: (1) A hydrothermal reaction was carried out using a mixed system containing vanadium oxalate, urea, samarium nitrate and water. The intermediate solid product obtained after the treatment was then annealed under an argon atmosphere to obtain samarium-doped VO2. (2) Samarium-doped VO2 was placed in a low-temperature plasma reactor and modified with ammonia.

3. The smart dimming glass according to claim 2, characterized in that, Step (1) specifically includes the following steps: adding 1.5-2 parts of vanadium pentoxide and oxalic acid dihydrate to 100 parts of water, with a molar ratio of vanadium pentoxide to oxalic acid dihydrate of 1:2.99-3.01; then heating to 70-75℃ and stirring for 3-5 hours to obtain a vanadium oxalate precursor solution; then adding 0.7-1.1 parts of urea and 0.1-0.12 parts of samarium nitrate to the vanadium oxalate precursor solution, stirring and mixing, and then placing it at 180-190℃ for hydrothermal reaction for 56-72 hours; then annealing the intermediate solid product obtained after treatment under an argon atmosphere at a temperature of 750-780℃ for 7-8 hours to obtain samarium-doped VO2.

4. The smart dimming glass according to claim 2, characterized in that, In step (1), the treatment specifically includes the following steps: the reaction mixture after hydrothermal reaction is allowed to stand, then the supernatant is removed, centrifuged, and washed with water and anhydrous ethanol in sequence, and then dried to obtain the intermediate solid product.

5. The smart dimming glass according to claim 2, characterized in that, In step (2), when ammonia is used for modification treatment, the treatment time is 10-30 min, the treatment voltage is 1-3 KV, and the treatment current is 0.5-1.5 A.

6. The smart dimming glass according to claim 1, characterized in that, The film-forming polymer is one or more of polyvinyl alcohol formaldehyde, polyvinyl alcohol acetal, and polyvinyl alcohol butyral; the molecular weight of the film-forming polymer is 80,000-100,000; and the solvent is N,N-dimethylformamide or N,N-dimethylacetamide.

7. The smart dimming glass according to claim 1, characterized in that, The preparation method of the silane coupling agent modified glass microspheres includes the following steps: mixing glass microspheres with 0.8-1.1% of the mass of the silane coupling agent for 60-90 min to obtain the glass microspheres; the particle size of the glass microspheres is 10-50 μm; the silane coupling agent is KH560 or KH570.

8. The smart dimming glass according to claim 7, characterized in that, The glass microspheres have a particle size of 25-30 μm.

9. A method for preparing smart dimming glass as described in any one of claims 1-8, characterized in that, Includes the following steps: S1: Clean and dry the glass; S2: Weigh each raw material for preparing the thin film layer; add the film-forming polymer to the solvent, stir and mix to dissolve, then add other raw materials for mixing, and prepare the coating mixture after vacuum degassing; uniformly coat the coating mixture onto the glass surface treated in step S1, and prepare the smart dimming glass after drying and curing.

10. The preparation method according to claim 9, characterized in that, Step S1 specifically includes the following steps: first, ultrasonically clean the glass with a cleaning solution for 8-10 minutes, then ultrasonically clean it with acetone and ethanol solutions for 8-10 minutes in sequence, then ultrasonically clean it with deionized water for 8-10 minutes, and finally dry the glass surface with nitrogen gas for later use.