Coated photovoltaic glass and preparation method thereof

Abstract

The invention relates to the technical field of photovoltaic glass, and discloses coated photovoltaic glass and a preparation method thereof.The preparation method comprises the steps that acrylic resin, modified nanometer titania, a fluorine-containing flame retardant, modified cellulose and shellac are added into mixing equipment and mixed, and coating liquid is obtained; and coating the surface of one side of a glass substrate with the prepared coating liquid by using a roller coating method, then carrying out low-temperature curing to form a composite protective layer, and after coating is completed, carrying out cleaning treatment to obtain the coated photovoltaic glass. The coated photovoltaic glass disclosed by the invention has relatively good flame retardance, impact resistance and weather resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic glass, in particular to a coated photovoltaic glass and a preparation method thereof. Background Art

[0002] Photovoltaic glass is an important component of solar cell modules, and its performance directly affects the efficiency and service life of solar cells. However, existing photovoltaic glass has certain deficiencies in terms of weather resistance and fire resistance. Especially in harsh environments such as high temperature and high humidity, it is prone to problems such as aging and cracking, which affects the overall performance and reliability of photovoltaic modules. In addition, traditional photovoltaic glass also has certain defects in flame retardant properties, making it difficult to meet the high requirements for material safety in modern construction and industrial applications. Therefore, how to avoid this phenomenon is the key to solving the problem. For example, patent CN1151409747B discloses a coated photovoltaic glass and its preparation method, which improves the hydrophobicity of the photovoltaic glass surface, but its flame retardant properties are not improved. Summary of the Invention

[0003] (1) Technical problems solved In view of the deficiencies in the prior art, the present invention provides a coated photovoltaic glass and a preparation method thereof, which has good flame retardancy, impact resistance and weather resistance.

[0004] (2) Technical solution To achieve the above-mentioned objectives, the present invention provides the following technical solution: a coated photovoltaic glass, comprising a glass substrate and a composite protective layer arranged on the glass substrate, wherein the raw materials of the composite protective layer include, by weight: 60-70 parts by weight of acrylic resin, 1-2 parts by weight of modified nano titanium dioxide, 0.1-0.3 parts by weight of a fluorine-containing flame retardant, 0.2-0.5 parts by weight of modified cellulose, and 2-4 parts by weight of shellac.

[0005] Furthermore, the preparation method of the modified nano-titanium dioxide is: 40 mL of isopropanol and 5 mL of deionized water are mixed, and then 1.4-1.8 g of γ-methacryloxypropyltrimethoxysilane coupling agent is added, stirred for 50-60 minutes, and then 12.6-13 g of nano-titanium dioxide is added thereto, reacted at 75-80° C. for 4-6 hours, and dried to obtain olefinated nano-titanium dioxide.

[0006] Furthermore, the preparation method of the fluorine-containing flame retardant is: S1. Under inert gas, 4,4'-diaminodiphenyl sulfone and triethylamine were added to a reactor containing acetonitrile solvent, the temperature was raised to 40-45°C and stirred for 0.4-0.5 h, and then phenylphosphoryl dichloride was added. The reaction was carried out at 70-75°C for 12-16 h. After the reaction was completed, the reaction was cooled to room temperature, the solvent was eluted with methyl tert-butyl ether, and the intermediate 1 was obtained by filtration. S2. Add perfluorooctanoyl chloride and intermediate 1 to N,N-dimethylformamide solvent, stir and mix, continue to add pyridine catalyst, react at 75-85°C for 6-8h, and then distill under reduced pressure and wash to obtain a fluorine-containing flame retardant.

[0007] Furthermore, the usage ratio of acetonitrile, 4,4'-diaminodiphenyl sulfone, triethylamine, and phenylphosphoryl dichloride in S1 is 50-60 mL: 6.21-6.34 g: 0.01-0.02 g: 7.51-7.54 g.

[0008] Furthermore, the usage ratio of N,N-dimethylformamide, perfluorooctanoyl chloride, intermediate 1, and pyridine catalyst in S2 is 45-55 mL: 8.12-8.54 g: 4.1-4.3 g: 0.012-0.015 g.

[0009] Furthermore, the preparation method of the modified cellulose is: Step 1: Mix 2-(dodecyltrithiocarbonate)-2-methylpropionic acid, oxalyl chloride and dichloromethane, stir at a rate of 140-160 rpm, add ethyl acetate, react for 6-9 hours, and rotary evaporate to obtain an intermediate; Step 2: Mix the nanocellulose and N,N-dimethylacetamide, stir for 2-3 hours at a stirring rate of 140-180 rpm and a temperature of 120-140°C, then add lithium chloride, stir for 10-12 hours at a temperature of 80-85°C, then add triethylamine and the intermediate, stir for 20-22 hours at room temperature, then add methanol, filter, wash, and dry to obtain modified cellulose.

[0010] In the above reaction process, under the action of oxalyl chloride, the carboxyl group in 2-(dodecyltrithiocarbonate)-2-methylpropionic acid is chlorinated to obtain an intermediate. Then, in an N,N-dimethylacetamide / lithium chloride system, the hydroxyl group in the nanocellulose reacts with the acyl chloride group in the intermediate, and triethylamine is used as an acid-binding agent to obtain modified cellulose.

[0011] Furthermore, in the step 1, the usage ratio of 2-(dodecyltrithiocarbonate)-2-methylpropionic acid, oxalyl chloride, dichloromethane and ethyl acetate is 4.2-4.4 g: 2.5-2.9 g: 30-40 mL: 1.2-1.6 mL.

[0012] Furthermore, in the step 2, the usage ratio of nanocellulose, N,N-dimethylacetamide, lithium chloride, triethylamine and intermediate is 0.96-1.02 g: 50-55 mL: 2.5-2.65 g: 1.35-1.42 g: 0.28-0.33 g.

[0013] Furthermore, the preparation method of the coated photovoltaic glass is: adding acrylic resin, modified nano titanium dioxide, fluorine-containing flame retardant, modified cellulose, and shellac into a mixing device, mixing at a speed of 400-450r / min at 35-40°C for 25-35min to obtain a coating liquid; using a roller coating method to apply the prepared coating liquid on the surface of one side of the glass substrate, and then curing it at low temperature to form a composite protective layer, and cleaning it after the coating is completed to obtain the coated photovoltaic glass.

[0014] (3) Beneficial technical effects The present invention comprises the following steps: adding acrylic resin, modified nano titanium dioxide, fluorine-containing flame retardant, modified cellulose and shellac into a mixing device, mixing and obtaining a coating liquid; coating the prepared coating liquid on the surface of one side of a glass substrate by a roller coating method, and then curing the coating liquid at a low temperature to form a composite protective layer; and performing a cleaning process after the coating is completed to obtain the coated photovoltaic glass.

[0015] The modified nano-titanium dioxide in the coated photovoltaic glass enhances the UV resistance of the composite layer, extending the service life of the glass. The phosphorus and sulfur contained in the fluorinated flame retardant and modified cellulose provide excellent flame retardancy. When heated, phosphorus produces acidic substances such as phosphate and metaphosphate, which promote the dehydration of the material into carbon. These acidic substances further polyphosphate, coating the surface of the material and providing a flame retardant effect. Sulfur, at high temperatures, promotes the formation of a char layer on the polymer surface. This char acts as a barrier to heat and oxygen, slowing combustion and providing a flame retardant effect. The acrylic resin, modified cellulose, and fluorinated flame retardant entangle with each other, creating a tighter connection and forming a molecular cross-linked network. This enhances its mechanical properties and helps disperse and dissipate more force when subjected to external impact. DETAILED DESCRIPTION

[0016] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0017] The raw materials used in the following examples and comparative examples are all chemically pure, wherein the molecular weight of the acrylic resin used is 10,000.

[0018] Example 1 A coated photovoltaic glass comprises a glass substrate and a composite protective layer arranged on the glass substrate, wherein the raw materials of the composite protective layer include, by weight, 60 parts by weight of acrylic resin, 1 part by weight of modified nano titanium dioxide, 0.1 part by weight of a fluorine-containing flame retardant, 0.2 part by weight of modified cellulose, and 2 parts by weight of shellac.

[0019] The modified nano-titanium dioxide is prepared by mixing 40 mL of isopropanol and 5 mL of deionized water, adding 1.4 g of γ-methacryloxypropyltrimethoxysilane, stirring for 50 minutes, adding 12.6 g of nano-titanium dioxide, reacting at 75° C. for 4 hours, and drying to obtain olefinated nano-titanium dioxide.

[0020] The preparation method of the fluorine-containing flame retardant is: S1. Under nitrogen, 6.21 g of 4,4'-diaminodiphenyl sulfone and 0.01 g of triethylamine were added to a reactor containing 50 mL of acetonitrile. The temperature was raised to 40°C and stirred for 0.4 h. Then, 7.51 g of phenylphosphoryl dichloride was added and the mixture was reacted at 70°C for 12 h. After the reaction, the mixture was cooled to room temperature, the solvent was eluted with methyl tert-butyl ether, and the mixture was filtered to obtain Intermediate 1. S2. Add 8.12 g of perfluorooctanoyl chloride and 4.1 g of intermediate 1 to 45 mL of N,N-dimethylformamide, stir and mix, then add 0.012 g of pyridine and react at 75°C for 6 h. After reaction, distill under reduced pressure and wash to obtain a fluorinated flame retardant.

[0021] The preparation method of the modified cellulose is: Step 1: Mix 4.2 g of 2-(dodecyltrithiocarbonate)-2-methylpropionic acid, 2.5 g of oxalyl chloride, and 30 mL of dichloromethane. Stir at 140 rpm at room temperature and add 1.2 mL of ethyl acetate. React for 6 h, and rotary evaporate to obtain an intermediate. Step 2: Mix 0.96 g of nanocellulose and 50 mL of N,N-dimethylacetamide, stir at a stirring rate of 140 rpm and a temperature of 120°C for 2 h, then add 2.5 g of lithium chloride, stir at a temperature of 80°C for 10 h, then add 1.35 g of triethylamine and 0.28 g of the intermediate, stir at room temperature for 20 h, then add methanol, filter, wash, and dry to obtain modified cellulose.

[0022] The method for preparing the coated photovoltaic glass comprises: adding acrylic resin, modified nano-titanium dioxide, a fluorine-containing flame retardant, modified cellulose, and shellac into a mixing device, mixing at a rotation speed of 400 r / min and at 35° C. for 25 minutes to obtain a coating solution; coating the prepared coating solution on the surface of one side of a glass substrate by a roller coating method, and then curing at a low temperature to form a composite protective layer; and cleaning the coating after completion to obtain the coated photovoltaic glass.

[0023] Example 2 A coated photovoltaic glass comprises a glass substrate and a composite protective layer arranged on the glass substrate. The raw materials of the composite protective layer include, by weight, 70 parts by weight of acrylic resin, 2 parts by weight of modified nano titanium dioxide, 0.3 parts by weight of a fluorine-containing flame retardant, 0.5 parts by weight of modified cellulose, and 4 parts by weight of shellac.

[0024] The modified nano-titanium dioxide is prepared by mixing 40 mL of isopropanol and 5 mL of deionized water, adding 1.8 g of γ-methacryloxypropyltrimethoxysilane, stirring for 60 minutes, adding 13 g of nano-titanium dioxide, reacting at 80° C. for 6 hours, and drying to obtain olefinated nano-titanium dioxide.

[0025] The preparation method of the fluorine-containing flame retardant is: S1. Under nitrogen, 6.34 g of 4,4'-diaminodiphenyl sulfone and 0.02 g of triethylamine were added to a reactor containing 60 mL of acetonitrile. The temperature was raised to 45°C and stirred for 0.5 h. Then, 7.54 g of phenylphosphoryl dichloride was added and the mixture was reacted at 75°C for 16 h. After the reaction, the mixture was cooled to room temperature, the solvent was eluted with methyl tert-butyl ether, and the mixture was filtered to obtain Intermediate 1. S2. Add 8.54 g of perfluorooctanoyl chloride and 4.3 g of intermediate 1 to 55 mL of N,N-dimethylformamide, stir and mix, then add 0.015 g of pyridine. React at 85°C for 8 h. After reaction, distill under reduced pressure and wash to obtain a fluorinated flame retardant.

[0026] The preparation method of the modified cellulose is: Step 1: Mix 4.4 g of 2-(dodecyltrithiocarbonate)-2-methylpropionic acid, 2.9 g of oxalyl chloride, and 40 mL of dichloromethane. Stir at 160 rpm at room temperature and add 1.6 mL of ethyl acetate. React for 9 h and rotary evaporate to obtain an intermediate. Step 2: Mix 1.02 g of nanocellulose and 55 mL of N,N-dimethylacetamide, stir at a stirring rate of 180 rpm and a temperature of 140°C for 3 h, then add 2.65 g of lithium chloride, stir at a temperature of 85°C for 12 h, then add 1.42 g of triethylamine and 0.33 g of the intermediate, stir at room temperature for 22 h, then add methanol, filter, wash, and dry to obtain modified cellulose.

[0027] The method for preparing the coated photovoltaic glass comprises: adding acrylic resin, modified nano-titanium dioxide, a fluorine-containing flame retardant, modified cellulose, and shellac into a mixing device, mixing at a rotation speed of 450 r / min and at 40° C. for 35 minutes to obtain a coating solution; coating the prepared coating solution on the surface of one side of a glass substrate by a roller coating method, and then curing at a low temperature to form a composite protective layer; and cleaning the coating after completion to obtain the coated photovoltaic glass.

[0028] Example 3 A coated photovoltaic glass comprises a glass substrate and a composite protective layer arranged on the glass substrate, wherein the raw materials of the composite protective layer include, by weight, 65 parts by weight of acrylic resin, 1.5 parts by weight of modified nano titanium dioxide, 0.2 parts by weight of a fluorine-containing flame retardant, 0.3 parts by weight of modified cellulose, and 3 parts by weight of shellac.

[0029] The modified nano-titanium dioxide is prepared by mixing 40 mL of isopropanol and 5 mL of deionized water, adding 1.6 g of γ-methacryloxypropyltrimethoxysilane coupling agent, stirring for 55 minutes, adding 12.8 g of nano-titanium dioxide, reacting at 76° C. for 5 hours, and drying to obtain olefinated nano-titanium dioxide.

[0030] The preparation method of the fluorine-containing flame retardant is: S1. Under nitrogen, 6.24 g of 4,4'-diaminodiphenyl sulfone and 0.015 g of triethylamine were added to a reactor containing 55 mL of acetonitrile. The temperature was raised to 43°C and stirred for 0.45 h. Then, 7.52 g of phenylphosphoryl dichloride was added and the mixture was reacted at 72°C for 14 h. After the reaction, the mixture was cooled to room temperature, the solvent was eluted with methyl tert-butyl ether, and the mixture was filtered to obtain Intermediate 1. S2. Add 8.37 g of perfluorooctanoyl chloride and 4.2 g of intermediate 1 to 50 mL of N,N-dimethylformamide, stir and mix, then add 0.014 g of pyridine and react at 80°C for 7 h. After reaction, distill under reduced pressure and wash to obtain a fluorine-containing flame retardant.

[0031] The preparation method of the modified cellulose is: Step 1: Mix 4.3 g of 2-(dodecyltrithiocarbonate)-2-methylpropionic acid, 2.8 g of oxalyl chloride, and 35 mL of dichloromethane. Stir at 150 rpm at room temperature and add 1.4 mL of ethyl acetate. React for 7 h and rotary evaporate to obtain an intermediate. Step 2: Mix 0.97 g of nanocellulose and 52 mL of N,N-dimethylacetamide, stir at a stirring rate of 160 rpm and a temperature of 130°C for 2.5 hours, then add 2.63 g of lithium chloride, stir at a temperature of 82°C for 11 hours, then add 1.38 g of triethylamine and 0.31 g of the intermediate, stir at room temperature for 21 hours, then add methanol, filter, wash, and dry to obtain modified cellulose.

[0032] The method for preparing the coated photovoltaic glass comprises: adding acrylic resin, modified nano-titanium dioxide, a fluorine-containing flame retardant, modified cellulose, and shellac into a mixing device, mixing at a rotation speed of 420 r / min and at 38° C. for 30 minutes to obtain a coating solution; coating the prepared coating solution on the surface of one side of a glass substrate by a roller coating method, and then curing at a low temperature to form a composite protective layer; and cleaning the coating after completion to obtain the coated photovoltaic glass.

[0033] Example 4 A coated photovoltaic glass comprises a glass substrate and a composite protective layer arranged on the glass substrate, wherein the raw materials of the composite protective layer include, by weight, 60 parts by weight of acrylic resin, 1 part by weight of modified nano titanium dioxide, 0.1 part by weight of a fluorine-containing flame retardant, 0.2 part by weight of modified cellulose, and 2 parts by weight of shellac.

[0034] The modified nano-titanium dioxide is prepared by mixing 40 mL of isopropanol and 5 mL of deionized water, adding 1.4 g of γ-methacryloxypropyltrimethoxysilane coupling agent, stirring for 50 minutes, adding 12.6 g of nano-titanium dioxide, reacting at 75° C. for 4 hours, and drying to obtain olefinated nano-titanium dioxide.

[0035] The preparation method of the fluorine-containing flame retardant is: S1. Under nitrogen, 6.34 g of 4,4'-diaminodiphenyl sulfone and 0.02 g of triethylamine were added to a reactor containing 60 mL of acetonitrile. The temperature was raised to 45°C and stirred for 0.5 h. Then, 7.54 g of phenylphosphoryl dichloride was added and the mixture was reacted at 75°C for 16 h. After the reaction, the mixture was cooled to room temperature, the solvent was eluted with methyl tert-butyl ether, and the mixture was filtered to obtain Intermediate 1. S2. Add 8.54 g of perfluorooctanoyl chloride and 4.3 g of intermediate 1 to 55 mL of N,N-dimethylformamide, stir and mix, then add 0.015 g of pyridine. React at 85°C for 8 h. After reaction, distill under reduced pressure and wash to obtain a fluorinated flame retardant.

[0036] The preparation method of the modified cellulose is: Step 1: Mix 4.3 g of 2-(dodecyltrithiocarbonate)-2-methylpropionic acid, 2.8 g of oxalyl chloride, and 35 mL of dichloromethane. Stir at 150 rpm at room temperature and add 1.4 mL of ethyl acetate. React for 7 h and rotary evaporate to obtain an intermediate. Step 2: Mix 0.97 g of nanocellulose and 52 mL of N,N-dimethylacetamide, stir at a stirring rate of 160 rpm and a temperature of 130°C for 2.5 hours, then add 2.63 g of lithium chloride, stir at a temperature of 82°C for 11 hours, then add 1.38 g of triethylamine and 0.31 g of the intermediate, stir at room temperature for 21 hours, then add methanol, filter, wash, and dry to obtain modified cellulose.

[0037] The method for preparing the coated photovoltaic glass comprises: adding acrylic resin, modified nano-titanium dioxide, a fluorine-containing flame retardant, modified cellulose, and shellac into a mixing device, mixing at a rotation speed of 420 r / min and at 38° C. for 30 minutes to obtain a coating solution; coating the prepared coating solution on the surface of one side of a glass substrate by a roller coating method, and then curing at a low temperature to form a composite protective layer; and cleaning the coating after completion to obtain the coated photovoltaic glass.

[0038] Comparative Example 1 A coated photovoltaic glass comprises a glass substrate and a composite protective layer arranged on the glass substrate. The raw materials of the composite protective layer include, by weight, 60 parts by weight of acrylic resin, 1 part by weight of modified nano-titanium dioxide, 0.1 part by weight of intermediate 1, 0.2 part by weight of modified cellulose, and 2 parts by weight of shellac.

[0039] The modified nano-titanium dioxide is prepared by mixing 40 mL of isopropanol and 5 mL of deionized water, adding 1.4 g of γ-methacryloxypropyltrimethoxysilane coupling agent, stirring for 50 minutes, adding 12.6 g of nano-titanium dioxide, reacting at 75° C. for 6 hours, and drying to obtain olefinated nano-titanium dioxide.

[0040] The preparation method of the intermediate 1 is: S1. Under nitrogen, 6.34 g of 4,4'-diaminodiphenyl sulfone and 0.02 g of triethylamine were added to a reactor containing 60 mL of acetonitrile. The temperature was raised to 45°C and stirred for 0.5 h. Then, 7.54 g of phenylphosphoryl dichloride was added and the mixture was reacted at 75°C for 16 h. After the reaction, the mixture was cooled to room temperature, the solvent was eluted with methyl tert-butyl ether, and the mixture was filtered to obtain Intermediate 1. The preparation method of the modified cellulose is: Step 1: Mix 4.3 g of 2-(dodecyltrithiocarbonate)-2-methylpropionic acid, 2.8 g of oxalyl chloride, and 35 mL of dichloromethane. Stir at 150 rpm at room temperature and add 1.4 mL of ethyl acetate. React for 7 h and rotary evaporate to obtain an intermediate. Step 2: Mix 0.97 g of nanocellulose and 52 mL of N,N-dimethylacetamide, stir at a stirring rate of 160 rpm and a temperature of 130°C for 2.5 hours, then add 2.63 g of lithium chloride, stir at a temperature of 82°C for 11 hours, then add 1.38 g of triethylamine and 0.31 g of the intermediate, stir at room temperature for 21 hours, then add methanol, filter, wash, and dry to obtain modified cellulose.

[0041] The method for preparing the coated photovoltaic glass comprises: adding acrylic resin, modified nano-titanium dioxide, intermediate 1, modified cellulose, and shellac into a mixing device, mixing at a rotation speed of 420 r / min and at 38° C. for 30 minutes to obtain a coating solution; coating the prepared coating solution on the surface of one side of a glass substrate by a roller coating method, and then curing at a low temperature to form a composite protective layer; and cleaning the coating after completion to obtain the coated photovoltaic glass.

[0042] Comparative Example 2 A coated photovoltaic glass comprises a glass substrate and a composite protective layer arranged on the glass substrate. The raw materials of the composite protective layer include, by weight, 60 parts by weight of acrylic resin, 1 part by weight of modified nano-titanium dioxide, 0.1 part by weight of a fluorine-containing flame retardant, 0.2 part by weight of nano-cellulose, and 2 parts by weight of shellac.

[0043] The modified nano-titanium dioxide is prepared by mixing 40 mL of isopropanol and 5 mL of deionized water, adding 1.4 g of γ-methacryloxypropyltrimethoxysilane coupling agent, stirring for 50 minutes, adding 12.6 g of nano-titanium dioxide, reacting at 75° C. for 5 hours, and drying to obtain olefinated nano-titanium dioxide.

[0044] The preparation method of the fluorine-containing flame retardant is: S1. Under nitrogen, 6.34 g of 4,4'-diaminodiphenyl sulfone and 0.02 g of triethylamine were added to a reactor containing 60 mL of acetonitrile. The temperature was raised to 45°C and stirred for 0.5 h. Then, 7.54 g of phenylphosphoryl dichloride was added and the mixture was reacted at 75°C for 16 h. After the reaction, the mixture was cooled to room temperature, the solvent was eluted with methyl tert-butyl ether, and the mixture was filtered to obtain Intermediate 1. S2. Add 8.54 g of perfluorooctanoyl chloride and 4.3 g of intermediate 1 to 55 mL of N,N-dimethylformamide, stir and mix, then add 0.015 g of pyridine. React at 85°C for 8 h. After reaction, distill under reduced pressure and wash to obtain a fluorinated flame retardant.

[0045] The method for preparing the coated photovoltaic glass comprises: adding acrylic resin, modified nano-titanium dioxide, a fluorine-containing flame retardant, cellulose, and shellac into a mixing device, mixing at a rotation speed of 420 r / min and at 38° C. for 30 minutes to obtain a coating solution; coating the prepared coating solution on the surface of one side of a glass substrate by a roller coating method, and then curing at a low temperature to form a composite protective layer; and cleaning the coating after completion to obtain the coated photovoltaic glass.

[0046] Oxygen index test is carried out in accordance with GB / T 2406.2-2009; Impact resistance test: Steel ball impact test (227g steel ball free fall from a height of 1m). Post-impact state: no cracks or damage (composite protective layer disperses stress). Weathering test: UV aging for 1000h in accordance with GB / T 1865-2009 (Paints and varnishes - Artificial weathering and artificial radiation exposure).

[0047] Table 1: Performance tests.

[0048] project Oxygen index (%) impact resistance Weather resistance Example 1 31.2 No cracks No yellowing, no peeling Example 2 32.6 No cracks No yellowing, no peeling Example 3 30.5 No cracks No yellowing, no peeling Example 4 31.6 No cracks No yellowing, no peeling Comparative Example 1 30.7 Slightly crack-free No yellowing, no peeling Comparative Example 2 25.9 Slightly crack-free No yellowing, no peeling As can be seen from Table 1, the coated photovoltaic glass embodiments 1-4 of the present invention have better flame retardancy, impact resistance and weather resistance than comparative examples 1-2.

[0049] It should be noted that, in this document, the terms "comprise," "include," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not preclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0050] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A coated photovoltaic glass comprising a glass substrate and a composite protective layer disposed on the glass substrate, characterized in that: The raw materials of the composite protective layer include, by weight, 60-70 parts of acrylic resin, 1-2 parts of modified nano titanium dioxide, 0.1-0.3 parts of fluorine-containing flame retardant, 0.2-0.5 parts of modified cellulose, and 2-4 parts of shellac.

2. The coated photovoltaic glass according to claim 1, characterized in that: The preparation method of the modified nano-titanium dioxide comprises the following steps: mixing isopropyl alcohol and deionized water, adding γ-methacryloxypropyltrimethoxysilane coupling agent, stirring for 50-60 minutes, adding nano-titanium dioxide, reacting at 75-80° C. for 4-6 hours, and drying to obtain olefinated nano-titanium dioxide.

3. The coated photovoltaic glass according to claim 1, characterized in that: The preparation method of the fluorine-containing flame retardant is: S1. Under inert gas, 4,4'-diaminodiphenyl sulfone and triethylamine were added to a reactor containing acetonitrile solvent, the temperature was raised to 40-45°C and stirred for 0.4-0.5 h, and then phenylphosphoryl dichloride was added. The reaction was carried out at 70-75°C for 12-16 h. After the reaction was completed, the reaction was cooled to room temperature, the solvent was eluted with methyl tert-butyl ether, and the intermediate 1 was obtained by filtration. S2. Add perfluorooctanoyl chloride and intermediate 1 to N,N-dimethylformamide solvent, stir and mix, continue to add pyridine catalyst, react at 75-85°C for 6-8h, and then distill under reduced pressure and wash to obtain a fluorine-containing flame retardant.

4. The coated photovoltaic glass according to claim 3, characterized in that: The usage ratio of acetonitrile, 4,4'-diaminodiphenyl sulfone, triethylamine, and phenylphosphoryl dichloride in S1 is 50-60 mL: 6.21-6.34 g: 0.01-0.02 g: 7.51-7.54 g.

5. The coated photovoltaic glass according to claim 3, characterized in that: The usage ratio of N,N-dimethylformamide, perfluorooctanoyl chloride, intermediate 1, and pyridine catalyst in S2 is 45-55 mL: 8.12-8.54 g: 4.1-4.3 g: 0.012-0.015 g.

6. The coated photovoltaic glass according to claim 1, characterized in that: The preparation method of the modified cellulose is: Step 1: Mix 2-(dodecyltrithiocarbonate)-2-methylpropionic acid, oxalyl chloride and dichloromethane, stir at a rate of 140-160 rpm, add ethyl acetate, react for 6-9 hours, and rotary evaporate to obtain an intermediate; Step 2: Mix the nanocellulose and N,N-dimethylacetamide, stir for 2-3 hours at a stirring rate of 140-180 rpm and a temperature of 120-140°C, then add lithium chloride, stir for 10-12 hours at a temperature of 80-85°C, then add triethylamine and the intermediate, stir for 20-22 hours at room temperature, then add methanol, filter, wash, and dry to obtain modified cellulose.

7. The coated photovoltaic glass according to claim 6, characterized in that: In the step 1, the usage ratio of 2-(dodecyltrithiocarbonate)-2-methylpropionic acid, oxalyl chloride, dichloromethane and ethyl acetate is 4.2-4.4 g: 2.5-2.9 g: 30-40 mL: 1.2-1.6 mL.

8. The coated photovoltaic glass according to claim 6, characterized in that: In the step 2, the usage ratio of nanocellulose, N,N-dimethylacetamide, lithium chloride, triethylamine and intermediate is 0.96-1.02 g: 50-55 mL: 2.5-2.65 g: 1.35-1.42 g: 0.28-0.33 g.

9. A method for preparing the coated photovoltaic glass according to any one of claims 1 to 8, characterized in that: The method for preparing the coated photovoltaic glass comprises: adding acrylic resin, modified nano-titanium dioxide, a fluorine-containing flame retardant, modified cellulose, and shellac into a mixing device, mixing at a rotation speed of 400-450 r / min and at 35-40° C. for 25-35 minutes to obtain a coating solution; coating the prepared coating solution on the surface of one side of a glass substrate by a roller coating method, and then curing at a low temperature to form a composite protective layer; and cleaning the coating after completion to obtain the coated photovoltaic glass.