A method for preparing graphene-modified coating for solar photovoltaic power generation

Abstract

The invention discloses a method for preparing a graphene-modified coating for solar photovoltaic power generation, and belongs to the technical field of solar photovoltaic coatings. The invention uses water as a solvent and prepares the coating by two-step emulsification. Compared with solvent-based coatings, the coating has less organic volatility, less environmental pollution, and is green and environmentally friendly; the introduction of organic silicon has good compatibility with the matrix, which can greatly improve the high temperature resistance of the coating; by modifying graphene oxide, the agglomeration phenomenon is significantly reduced compared with ordinary graphene, and the corrosion resistance of the coating is significantly enhanced; the prepared additive can significantly enhance the UV resistance and a certain degree of water resistance of the coating, and the performance is long-term and stable. Therefore, the prepared coating has stable and efficient corrosion resistance, high temperature resistance, UV resistance and a certain degree of water resistance, and is green and environmentally friendly, and has important application value in the field of solar photovoltaic coating technology.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar photovoltaic coatings, and in particular, relates to a method for preparing a graphene-modified coating for solar photovoltaic power generation. Background Art

[0002] With the increasing exhaustion of energy and the deterioration of the environment, governments around the world have increasingly higher requirements for energy conservation and emission reduction, resulting in more and more attention being paid to the field of new energy. In the field of new energy, solar energy is a green, pollution-free and inexhaustible energy source. Compared with other energy sources, solar energy is universal in most areas of the earth and can be used locally. The use of solar energy is mainly based on the principle of photovoltaic effect, also known as photovoltaic effect, using solar cells to directly convert sunlight energy into electrical energy. Photovoltaic equipment is used in the production of silicon materials, silicon wafer processing, solar cell wafers, and the production of components, as well as the construction of corresponding pure water preparation, environmental protection treatment, purification projects, and testing equipment and simulators corresponding to the photovoltaic industry chain. The development scale and development prospects are broad.

[0003] Commonly used photovoltaic equipment, especially the solar panel brackets and shells are mostly made of aluminum alloy. In order to protect the metal, it is usually necessary to apply coatings or paint. However, photovoltaic equipment is generally installed outdoors. Under long-term sunlight exposure and rain erosion, it is easy to fall off, causing corrosion of metal materials and affecting the service life of photovoltaic equipment.

[0004] Graphene is a two-dimensional honeycomb planar structure composed of tightly stacked single-layer carbon atoms. Due to its special structure, graphene has very high electrical and thermal conductivity. Paints made from graphene have excellent anti-corrosion and waterproof properties. Applying it to photovoltaic equipment can significantly enhance the anti-corrosion and anti-rust properties of photovoltaic equipment. However, graphene itself is an inorganic substance, and the paint matrix often uses organic resins. Graphene has poor compatibility with organic resins and is prone to agglomeration in the paint, which seriously affects the performance of the paint. In addition, since the paint is exposed to sunlight for a long time, it is prone to oxidation and shedding, which places more stringent requirements on the paint's anti-ultraviolet performance. Therefore, the above problems need to be solved to meet the higher demands in the field of solar photovoltaic paint technology. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the prior art and provide a method for preparing a graphene-modified coating for solar photovoltaic power generation.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A method for preparing a graphene-modified coating for solar photovoltaic power generation comprises the following steps:

[0008] A1, adding modified graphene into deionized water, and dispersing by ultrasonic to obtain a modified graphene suspension;

[0009] A2, adding acrylic acid, acrylic acid ester, methacrylate and part of emulsifier into deionized water, emulsifying to obtain a pre-emulsion;

[0010] A3. Add pre-emulsion, remaining emulsifier, modified graphene suspension, γ-methacryloxypropyltrimethoxysilane (KH-570 silane coupling agent) and azobisisopropylimidazoline (water-soluble initiator) into deionized water, keep the mixture at 80°C for 4 hours to initiate polymerization reaction. After the reaction is completed, a graphene-modified coating for solar photovoltaic power generation is obtained.

[0011] Furthermore, the raw materials in step A1 are calculated in parts by weight as follows: 6-10 parts of modified graphene and 80-100 parts of deionized water.

[0012] Furthermore, the raw materials in step A2 are calculated in parts by weight as follows: 20-24 parts of acrylic acid, 16-20 parts of acrylic acid ester, 18-22 parts of methacrylate, and 56-60 parts of deionized water.

[0013] Furthermore, the raw materials in step A3 are calculated in parts by weight as follows: 60-70 parts of deionized water, 40-50 parts of pre-emulsion, 10-20 parts of modified graphene suspension, 8-16 parts of γ-methacryloxypropyltrimethoxysilane, and 0.6-1 parts of azobisisopropylimidazoline.

[0014] Furthermore, the emulsifier is prepared by compounding alkylphenol polyoxyethylene ether and sodium dodecyl sulfate in a mass ratio of 2:1; and the usage ratio of the emulsifier in step A2 and step A3 is 1:2, and the total amount of the emulsifier is 6-12 mL.

[0015] The paint uses water as solvent and is made through two-step emulsification, which is more environmentally friendly than solvent-based paints. The emulsifier is an anionic and non-ionic compound emulsifier with better emulsification effect. Acrylic resin is used as the paint matrix, which has high oxygen resistance and weather resistance, and acrylate and methacrylate are selected as monomers to make the prepared paint have better weather resistance. KH-570 silane coupling agent, as a kind of silicone, can greatly enhance the heat resistance and certain water resistance of the matrix, and under the action of the initiator, it can be polymerized to the molecular chain of the matrix to improve the compatibility with the matrix.

[0016] Furthermore, the modified graphene is prepared by the following steps:

[0017] Add N,N-dimethylformamide (DMF), dicyclohexylcarbodiimide (DCC, dehydrating agent) and auxiliary agents into a flask, stir in a 50°C water bath until the solid is completely dissolved, then slowly add graphene oxide dispersion (DMF as the dispersion medium, concentration of 10 mg / mL) with magnetic stirring. After the addition, ultrasonically treat for 30 minutes, react at 65°C for 5 hours with continuous stirring. After the reaction is completed, distill under reduced pressure and freeze-dry to obtain modified graphene.

[0018] The use of graphene oxide has better conductivity and corrosion resistance than ordinary graphene; and through the chemical bonding action of grafting additives, it can greatly improve the interface compatibility between graphene oxide and the matrix, promote the dispersion of graphene oxide, reduce agglomeration, and enable the performance of graphene oxide to be fully utilized.

[0019] Furthermore, the usage ratio of DMF, DCC, additive and graphene oxide dispersion is 50 mL:25 g:10 g:100 mL.

[0020] Furthermore, the auxiliary agent is prepared by the following steps:

[0021] S1. In a three-necked flask equipped with a stirring device, 2,2,6,6-tetramethylpiperidinol, n-decane and molybdenum trioxide were mixed and stirred evenly, heated to 80°C, and tert-butyl hydroperoxide aqueous solution (mass fraction 68%) was added dropwise. After the addition was completed, reflux reaction was carried out for 6.5 hours, filtered, activated carbon was added to the filtrate and stirred for 2 hours, allowed to stand, filtered, the filtrate was taken, and n-octane was removed by vacuum distillation to obtain intermediate 1; the ratio of 2,2,6,6-tetramethylpiperidinol, n-decane, molybdenum trioxide and tert-butyl hydroperoxide aqueous solution was 15.7 g:18.4 g:0.3 g:15 mL;

[0022] Under the catalysis of molybdenum trioxide and the oxidation of tert-butyl hydroperoxide, 2,2,6,6-tetramethylpiperidinol and n-decane undergo a free radical coupling reaction; n-decane participates in the reaction process as a reactant and also acts as a reaction solvent, which can reduce the formation of by-products to obtain intermediate 1; the specific reaction process is shown below:

[0023]

[0024] S2. In a three-necked flask equipped with a stirring device, add cyanuric chloride, sodium hydroxide solution (mass fraction 12%), triethylamine and toluene in sequence, stir at room temperature for 10 minutes, slowly add intermediate 1, keep warm for 4 hours, and after the reaction is completed, filter, wash the filtrate with saturated brine three times, dry the organic phase with anhydrous magnesium sulfate, filter, and purify by column chromatography (the eluent is a mixed solvent of methanol / ethyl acetate, the volume ratio of the two is 1:8), and remove the eluent by rotary evaporation to obtain intermediate 2; the ratio of cyanuric chloride, sodium hydroxide solution, triethylamine, toluene, and intermediate 1 is 20.4g:10mL:15mL:100mL:62.8g;

[0025] Cyanuric chloride and intermediate 1 are substituted, and the molar ratio of the two is controlled to be close to 1:2 and cyanuric chloride is slightly excessive, so that only two chlorine groups on cyanuric chloride participate in the reaction, and triethylamine removes the hydrogen chloride generated by the reaction to obtain intermediate 2; the specific reaction process is as follows:

[0026]

[0027] S3. In a three-necked flask equipped with a stirring device, add intermediate 2, chlorobenzene and anhydrous aluminum chloride, stir in an ice-water bath for 30 minutes, add resorcinol, react at 85°C for 4 hours, and after the reaction is completed, slowly drop dilute hydrochloric acid (mass fraction 2%) into the flask, recover the chlorobenzene-water azeotrope by atmospheric distillation, raise the temperature to 100°C, filter while hot, wash with dilute hydrochloric acid and water, and vacuum dry to obtain intermediate 3; the ratio of intermediate 2, chlorobenzene, anhydrous aluminum chloride, resorcinol, and dilute hydrochloric acid is 73.6g:150mL:13.3g:12.5g:150mL;

[0028] The specific reaction process is as follows:

[0029]

[0030] S4. In a three-necked flask equipped with a stirring device, add DMF, sodium hydroxide solution (mass fraction 12%) and intermediate 3, stir until the solid is completely dissolved, heat to 80°C, and add 3-chloro-2-chloromethyl propylene dropwise while reacting. The addition is completed within 2 minutes, and the reaction is continued at a constant temperature for 6 hours. After the reaction is completed, filter, wash with water, and dry to obtain intermediate 4; the ratio of DMF, sodium hydroxide solution, intermediate 3, and 3-chloro-2-chloromethyl propylene used is 150mL:20mL:81.1g:15.6g;

[0031] Intermediate 3 is substituted with 3-chloro-2-chloromethyl propylene, and the molar ratio of the two is controlled to be close to 1:1 and 3-chloro-2-chloromethyl propylene is slightly excessive to obtain intermediate 4; the specific reaction process is as follows:

[0032]

[0033] S5. At room temperature, under nitrogen protection, in a three-necked flask equipped with a stirring reflux device, the intermediate 4, ethylenediamine, triethylamine and chlorobenzene were stirred and mixed uniformly, and the reaction temperature was controlled to be 75°C for 4 hours. After the reaction was completed, the mixture was filtered, and part of the solvent was removed by rotary evaporation. The mixture was then purified by column chromatography (the eluent was a mixed solvent of benzene / ethyl acetate in a volume ratio of 2:7), and the eluent was removed by rotary evaporation to obtain an auxiliary agent. The ratio of the intermediate 4, ethylenediamine, triethylamine and chlorobenzene was 89.8 g:7.2 g:15 mL:120 mL.

[0034] Intermediate 4 and ethylenediamine undergo nucleophilic substitution. By controlling the molar ratio of the two to be close to 1:1 and a slight excess of ethylenediamine, only one amino group on ethylenediamine participates in the reaction. Triethylamine removes the hydrogen chloride generated by the reaction to obtain an auxiliary agent. The specific reaction process is shown below:

[0035]

[0036] The prepared auxiliary agent triazine structure is the center, connected with o-hydroxyphenyl, hindered amine, long carbon chain and carbon-carbon double bond; the hydroxyl hydrogen on the o-hydroxyphenyl benzene ring can form an intramolecular hydrogen bond with the adjacent nitrogen atom in triazine, forming a chelate ring. After absorbing ultraviolet light, the chelate ring opens to form an unstable compound, which returns to a stable state by releasing energy, closing the chelate ring, and absorbing ultraviolet light repeatedly, thereby improving the anti-ultraviolet performance of the matrix and making the performance long-lasting; in addition, the hindered amine will decompose into two in light protection. Hydrogen peroxide produces stable nitroxide free radicals, which can very effectively capture the free radicals produced in photo-oxidative degradation, and act synergistically with triazine anti-UV agents to significantly enhance the anti-UV properties of the matrix; in addition, the long carbon chain belongs to the methylene chain segment, which has strong hydrophobicity and can improve the waterproof performance and flexibility of the matrix to a certain extent; finally, the carbon-carbon double bonds contained in the additive can produce chemical bonds with the matrix under the action of trace initiators, thereby improving the compatibility between the additive and the matrix and giving full play to the performance of the additive.

[0037] It should be noted that the end of the additive contains an amino group and is grafted onto graphene oxide through chemical bonding, which can effectively prevent the migration and seepage of the additive and ensure the durability of the additive's performance.

[0038] Beneficial effects of the present invention:

[0039] 1. The present invention uses water as solvent and prepares the coating through two-step emulsification. Compared with solvent-based coatings, the organic volatility is less, the environmental pollution is less, and it is green and environmentally friendly;

[0040] 2. The introduction of organic silicon has good compatibility with the substrate and can greatly improve the high temperature resistance of the coating;

[0041] 3. By modifying graphene oxide, the agglomeration phenomenon is significantly reduced compared with ordinary graphene, which significantly enhances the corrosion resistance of the coating;

[0042] 4. The prepared additive can significantly enhance the coating's UV resistance and a certain degree of waterproofness and flexibility, and the performance is long-lasting and stable.

[0043] Therefore, the prepared coating has stable and efficient corrosion resistance, high temperature resistance, UV resistance, a certain degree of waterproofness and flexibility, and is green and environmentally friendly, and has important application value in the field of solar photovoltaic coating technology. DETAILED DESCRIPTION

[0044] 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. Example 1

[0045] Preparation aids:

[0046] S1. In a three-necked flask equipped with a stirring device, 15.7 g of 2,2,6,6-tetramethylpiperidinol, 18.4 g of n-decane and 0.3 g of molybdenum trioxide were mixed and stirred evenly, heated to 80°C, and 15 mL of tert-butyl hydroperoxide aqueous solution (mass fraction 68%) was added dropwise. After the addition was completed, reflux reaction was performed for 6.5 h, filtered, activated carbon was added to the filtrate, stirred for 2 h, allowed to stand, filtered, the filtrate was taken, and n-octane was removed by vacuum distillation to obtain intermediate 1;

[0047] S2. In a three-necked flask equipped with a stirring device, 20.4 g of cyanuric chloride, 10 mL of sodium hydroxide solution (mass fraction 12%), 15 mL of triethylamine and 100 mL of toluene were added in sequence. After stirring at room temperature for 10 min, 62.8 g of intermediate 1 was slowly added. The reaction was kept warm for 4 h. After the reaction was completed, the mixture was filtered and the filtrate was washed 3 times with saturated brine. The organic phase was dried over anhydrous magnesium sulfate, filtered, and purified by column chromatography (the eluent was a mixed solvent of methanol / ethyl acetate in a volume ratio of 1:8). The eluent was removed by rotary evaporation to obtain intermediate 2.

[0048] S3. In a three-necked flask equipped with a stirring device, add 73.6 g of intermediate 2, 150 mL of chlorobenzene and 13.3 g of anhydrous aluminum chloride, stir in an ice-water bath for 30 min, add 12.5 g of resorcinol, react at 85°C for 4 hours, and after the reaction is complete, slowly drop 150 mL of dilute hydrochloric acid (mass fraction 2%) into the flask, recover the azeotrope of chlorobenzene and water by atmospheric distillation, raise the temperature to 100°C, filter while hot, wash with dilute hydrochloric acid and water, and dry in vacuo to obtain intermediate 3;

[0049] S4. In a three-necked flask equipped with a stirring device, add 150 mL of DMF, 20 mL of sodium hydroxide solution (mass fraction 12%) and 81.1 g of intermediate 3, stir until the solid is completely dissolved, heat to 80°C, and dropwise add 15.6 g of 3-chloro-2-chloromethyl propylene while reacting. The addition is completed within 2 min, and the reaction is continued at a constant temperature for 6 h. After the reaction is completed, filter with suction, wash with water, and dry to obtain intermediate 4;

[0050] S5. At room temperature, under nitrogen protection, 89.8 g of intermediate 4, 7.2 g of ethylenediamine, 15 mL of triethylamine and 120 mL of chlorobenzene were stirred and mixed evenly in a three-necked flask equipped with a stirring reflux device. The reaction temperature was controlled to 75°C and the reaction was carried out for 4 hours. After the reaction was completed, it was filtered, and part of the solvent was removed by rotary evaporation. Then, it was purified by column chromatography (the eluent was a mixed solvent of benzene / ethyl acetate, and the volume ratio of the two was 2:7), and the eluent was removed by rotary evaporation to obtain an auxiliary agent. Example 2

[0051] Preparation aids:

[0052] S1. In a three-necked flask equipped with a stirring device, 31.4 g of 2,2,6,6-tetramethylpiperidinol, 36.8 g of n-decane and 0.6 g of molybdenum trioxide were mixed and stirred evenly, heated to 80°C, and 30 mL of tert-butyl hydroperoxide aqueous solution (mass fraction 68%) was added dropwise. After the addition was completed, reflux reaction was performed for 6.5 h, filtered, activated carbon was added to the filtrate, stirred for 2 h, allowed to stand, filtered, the filtrate was taken, and n-octane was removed by vacuum distillation to obtain intermediate 1;

[0053] S2. In a three-necked flask equipped with a stirring device, 40.8 g of cyanuric chloride, 20 mL of sodium hydroxide solution (mass fraction 12%), 30 mL of triethylamine and 200 mL of toluene were added in sequence. After stirring at room temperature for 10 min, 125.6 g of intermediate 1 was slowly added. The reaction was kept warm for 4 h. After the reaction was completed, the filtrate was filtered and washed with saturated brine three times. The organic phase was dried over anhydrous magnesium sulfate, filtered, and purified by column chromatography (the eluent was a mixed solvent of methanol / ethyl acetate, and the volume ratio of the two was 1:8). The eluent was removed by rotary evaporation to obtain intermediate 2;

[0054] S3, in a three-necked flask equipped with a stirring device, add 147.2g of intermediate 2, 300mL of chlorobenzene and 26.6g of anhydrous aluminum chloride, stir in an ice-water bath for 30min, add 25g of resorcinol, react at 85°C for 4 hours, and after the reaction is complete, slowly drop 300mL of dilute hydrochloric acid (mass fraction 2%) into the flask, recover the chlorobenzene-water azeotrope by atmospheric distillation, raise the temperature to 100°C, filter while hot, wash with dilute hydrochloric acid and water, and vacuum dry to obtain intermediate 3;

[0055] S4. In a three-necked flask equipped with a stirring device, add 300 mL of DMF, 40 mL of sodium hydroxide solution (mass fraction 12%) and 162.2 g of intermediate 3, stir until the solid is completely dissolved, heat to 80°C, and dropwise add 31.2 g of 3-chloro-2-chloromethyl propylene while reacting. The addition should be completed within 2 min, and the reaction should be continued at a constant temperature for 6 h. After the reaction is completed, filter with suction, wash with water, and dry to obtain intermediate 4;

[0056] S5. At room temperature, under nitrogen protection, 179.6 g of intermediate 4, 14.4 g of ethylenediamine, 30 mL of triethylamine and 240 mL of chlorobenzene were stirred and mixed evenly in a three-necked flask equipped with a stirring reflux device. The reaction temperature was controlled to 75°C and the reaction was carried out for 4 hours. After the reaction was completed, the product was filtered, and part of the solvent was removed by rotary evaporation. The product was then purified by column chromatography (the eluent was a mixed solvent of benzene / ethyl acetate in a volume ratio of 2:7), and the eluent was removed by rotary evaporation to obtain an auxiliary agent. Example 3

[0057] Preparation of modified graphene:

[0058] 50 mL of DMF, 25 g of DCC and 10 g of the auxiliary agent prepared in Example 1 were added to a flask, and stirred in a 50° C. water bath until the solid was completely dissolved. Then, 100 mL of graphene oxide dispersion (DMF as the dispersion medium, with a concentration of 10 mg / mL) was slowly added while magnetic stirring was performed. After the addition was completed, ultrasonic treatment was performed for 30 min, and the mixture was reacted at 65° C. for 5 h with continuous stirring. After the reaction was completed, vacuum distillation was performed and freeze-dried to obtain modified graphene. Example 4

[0059] Preparation of modified graphene:

[0060] 100 mL of DMF, 50 g of DCC and 20 g of the auxiliary agent prepared in Example 2 were added to a flask, and stirred in a 50°C water bath until the solid was completely dissolved. Then, 200 mL of graphene oxide dispersion (DMF as the dispersion medium, concentration of 10 mg / mL) was slowly added while magnetic stirring was performed. After the addition, ultrasonic treatment was performed for 30 min, and the mixture was reacted at 65°C for 5 h with continuous stirring. After the reaction was completed, the mixture was distilled under reduced pressure and freeze-dried to obtain modified graphene. Example 5

[0061] A1. Add 6 g of the modified graphene prepared in Example 3 into 80 mL of deionized water and disperse by ultrasonic to obtain a modified graphene suspension;

[0062] A2, 20g acrylic acid, 16g acrylate, 18g methacrylate and 2mL emulsifier were added to 56mL deionized water, emulsified to obtain a pre-emulsion;

[0063] A3. Add 40 mL of pre-emulsion, 4 mL of emulsifier, 10 mL of modified graphene suspension, 8 g of KH-570 silane coupling agent and 0.6 g of azodiisopropylimidazoline to 60 mL of deionized water, and heat at 80°C for 4 hours to initiate polymerization. After the reaction is completed, a graphene-modified coating for solar photovoltaic power generation is obtained.

[0064] The emulsifier is prepared by compounding emulsifier OP-10 and sodium lauryl sulfate in a mass ratio of 2:1. Example 6

[0065] A1. Add 8 g of the modified graphene prepared in Example 3 into 90 mL of deionized water and disperse by ultrasonic to obtain a modified graphene suspension;

[0066] A2, add 22g acrylic acid, 18g acrylate, 20g methacrylate and 3mL emulsifier into 58mL deionized water, emulsify and obtain a pre-emulsion;

[0067] A3. Add 45 mL of pre-emulsion, 6 mL of emulsifier, 15 mL of modified graphene suspension, 12 g of KH-570 silane coupling agent and 0.8 g of azodiisopropylimidazoline to 65 mL of deionized water, and heat at 80°C for 4 hours to initiate polymerization. After the reaction is completed, a graphene-modified coating for solar photovoltaic power generation is obtained.

[0068] The emulsifier is prepared by compounding emulsifier OP-10 and sodium lauryl sulfate in a mass ratio of 2:1. Example 7

[0069] A1. Add 10 g of the modified graphene prepared in Example 3 into 100 mL of deionized water and disperse by ultrasonic to obtain a modified graphene suspension;

[0070] A2, add 24g acrylic acid, 20g acrylate, 22g methacrylate and 4mL emulsifier into 60mL deionized water, emulsify and obtain a pre-emulsion;

[0071] A3. Add 50 mL of pre-emulsion, 8 mL of emulsifier, 20 mL of modified graphene suspension, 16 g of KH-570 silane coupling agent and 1 g of azodiisopropylimidazoline to 70 mL of deionized water, and keep the reaction at 80°C for 4 hours to initiate polymerization. After the reaction is completed, a graphene-modified coating for solar photovoltaic power generation is obtained.

[0072] The emulsifier is prepared by compounding emulsifier OP-10 and sodium lauryl sulfate in a mass ratio of 2:1.

[0073] Comparative Example 1

[0074] Different from Example 7, ordinary graphene is used.

[0075] Comparative Example 2

[0076] The difference from Example 7 is that the KH-570 silane coupling agent is not used.

[0077] Comparative Example 3

[0078] A commercially available acrylic graphene anti-corrosion coating produced by Shandong Zixin Innovation Materials Technology Co., Ltd. was used.

[0079] The following performance tests were performed on Examples 5-7 and Comparative Examples 1-3:

[0080] Adopt national standard GB / T 1720-1989 to measure adhesion;

[0081] The flexibility was determined using the national standard GB / T 1731-1993;

[0082] The national standard GB / T 9274-1988 is used to determine the acid and alkali resistance;

[0083] The water resistance was determined using the national standard GB / T 1733-1993;

[0084] The national standard GB / T 1771-2007 is used to determine the salt spray resistance;

[0085] The anti-ultraviolet performance is measured according to the national standard GB / T 1865-2009 and rated according to the GB / T 1766 standard;

[0086] High temperature resistance test: Spread the sample evenly on a square sheet with a side length of 1 cm and a thickness of 0.5 mm, and bake it in a constant temperature oven at 300°C for 30 minutes. After taking it out, observe whether the coating has bubbles or slag. If not, it is judged to be heat resistant greater than 300°C.

[0087] The measurement results are shown in the following table:

[0088]

[0089] It can be seen from the above table that the coating prepared by the present invention has stable and efficient corrosion resistance, UV resistance, a certain degree of water resistance and flexibility due to the addition of modified graphene, and the addition of silicone can improve the high temperature resistance of the coating. Therefore, the present invention has important application value in the field of solar photovoltaic coating technology.

[0090] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0091] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A method for preparing a graphene-modified coating for solar photovoltaic power generation, characterized in that: The following steps are involved: A1, adding modified graphene into deionized water, and dispersing by ultrasonic to obtain a modified graphene suspension; A2, adding acrylic acid, acrylic acid ester, methacrylate and part of emulsifier into deionized water, emulsifying to obtain a pre-emulsion; A3, adding pre-emulsion, remaining emulsifier, modified graphene suspension, γ-methacryloxypropyltrimethoxysilane and azodiisopropylimidazoline into deionized water, keeping the reaction at 80° C. for 4 hours, and the reaction is completed to obtain a graphene modified coating for solar photovoltaic power generation; Wherein, the modified graphene is prepared by the following steps: DMF, DCC and an auxiliary agent were added to a flask, stirred in a water bath at 50°C until the solid dissolved, and graphene oxide dispersion was added, magnetic stirring was performed, ultrasonic treatment was performed for 30 minutes, and the reaction was performed at 65°C for 5 hours with continuous stirring. After the reaction was completed, vacuum distillation was performed, and freeze-drying was performed to obtain modified graphene; Wherein, the auxiliary agent is prepared by the following steps: S1. Mix 2,2,6,6-tetramethylpiperidinol, n-decane and molybdenum trioxide and stir evenly, heat to 80°C, add tert-butyl hydroperoxide aqueous solution dropwise, reflux for 6.5h, filter with suction, add activated carbon to the filtrate and stir for 2h, let stand, filter with suction, and distill under reduced pressure to obtain intermediate 1; the ratio of 2,2,6,6-tetramethylpiperidinol, n-decane, molybdenum trioxide and tert-butyl hydroperoxide aqueous solution is 15.7g:18.4g:0.3g:15mL; S2. In a three-necked flask, cyanuric chloride, sodium hydroxide solution, triethylamine and toluene were added in sequence. After stirring at room temperature for 10 min, intermediate 1 was added and the reaction was kept warm for 4 h. After the reaction was completed, the filtrate was filtered and washed 3 times with saturated brine, dried over anhydrous magnesium sulfate, filtered, and purified by column chromatography and rotary evaporation to obtain intermediate 2; the ratio of cyanuric chloride, sodium hydroxide solution, triethylamine, toluene and intermediate 1 was 20.4 g:10 mL:15 mL:100 mL:62.8 g; S3, intermediate 2, chlorobenzene and anhydrous aluminum chloride, stirred in an ice-water bath for 30 min, resorcinol was added, reacted at 85°C for 4 h, dilute hydrochloric acid was added dropwise, chlorobenzene and water azeotrope were recovered by atmospheric distillation, the temperature was raised to 100°C, filtered while hot, washed with dilute hydrochloric acid and water, and dried in vacuo to obtain intermediate 3; the ratio of intermediate 2, chlorobenzene, anhydrous aluminum chloride, resorcinol and dilute hydrochloric acid was 73.6 g:150 mL:13.3 g:12.5 g:150 mL; S4. In a three-necked flask, add DMF, sodium hydroxide solution and intermediate 3, stir, heat to 80°C, add 3-chloro-2-chloromethyl propylene dropwise while reacting, continue the reaction at constant temperature for 6 hours, and after the reaction is completed, filter, wash with water and dry to obtain intermediate 4; the ratio of DMF, sodium hydroxide solution, intermediate 3 and 3-chloro-2-chloromethyl propylene is 150mL:20mL:81.1g:15.6g; S5. At room temperature, under nitrogen protection, stir and mix intermediate 4, ethylenediamine, triethylamine and chlorobenzene evenly, react at 75°C for 4 hours, filter, rotary evaporate, purify by column chromatography, and rotary evaporate to obtain an auxiliary agent; the ratio of intermediate 4, ethylenediamine, triethylamine and chlorobenzene is 89.8g:7.2g:15mL:120mL.

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