Corrosion-resistant photovoltaic module material and preparation method thereof

Abstract

The invention discloses a corrosion-resistant photovoltaic module material and a preparation method thereof, and belongs to the technical field of photovoltaic modules, zinc oxide nanoneedles grow on the surface of modified mica powder in an oriented manner to obtain zinc oxide / mica powder, and the zinc oxide / mica powder is treated by 3-aminopropyltriethoxysilane to be grafted with 2-hydroxyaniline to obtain the corrosion-resistant photovoltaic module material. Zinc oxide can cooperate with aniline to be adsorbed on the metal surface to form a compact hydrophobic protection layer, and contact between a corrosion medium and metal is blocked through a physical shielding effect, so that an electrochemical corrosion reaction is inhibited; the growth of the zinc oxide nanoneedles can improve the specific surface area and the surface roughness of the modified mica, meanwhile, the zinc oxide nanoneedles are endowed with photocatalytic activity, active oxygen is generated under illumination, organic pollutants are decomposed, microorganism breeding is inhibited, and therefore biological corrosion is relieved; the aging of the anti-corrosion emulsion coating is reduced, and the adhesion of the coating to a photovoltaic cell can be increased through a mechanical interlocking effect by virtue of the nano needle-shaped structure.

Description

Technical Field

[0001] The present invention belongs to the technical field of photovoltaic modules, and specifically relates to a corrosion-resistant photovoltaic module material and a preparation method thereof. Background Art

[0002] When photovoltaic modules are used under conditions of high temperature, high humidity, and high light intensity, moisture or water gradually penetrates the module interior. Under the influence of light and heat, the EVA undergoes a deacetylation reaction, producing acetic acid. In the presence of acetic acid, a potential difference is formed between the two metals of the tin-copper solder strip, and the metal with the lower potential will be corroded. Furthermore, the acetic acid in the EVA film reacts with residual peroxide to form hydroperoxides, which can oxidize and blacken the silver grid lines on the surface of the crystalline silicon cell.

[0003] When photovoltaic modules are used outdoors, exposure to high temperatures, high humidity, and strong sunlight can cause residual peroxide crosslinkers in the photovoltaic encapsulation film system to decompose. The decomposed substances further form hydroperoxides, which are highly reactive and can easily corrode the soldering ribbons on the surface of crystalline silicon photovoltaic cells into black silver oxide. For ethylene vinyl acetate photovoltaic encapsulation films, high temperatures and high humidity can also cause the ethylene vinyl acetate to decompose and produce acetic acid, which corrodes the soldering ribbons and busbars, reducing the output power and durability of the photovoltaic modules.

[0004] The common solution currently is to add corrosion-resistant metal oxides and hydroxides, but the amount added is large and the processing cost is high. Although it can reduce corrosion, it will affect the transmittance of the film and cannot meet the demand for high-transmittance film.

[0005] Chinese patent application CN117153919A discloses a corrosion-resistant photovoltaic module and a method for preparing the same. In this solution, an anti-corrosion coating is applied to the busbars and solder strips of photovoltaic cells. The raw materials for the anti-corrosion coating include inorganic fillers and vinyl acetate-ethylene copolymer (VAE) emulsion. However, when the photovoltaic module is used under conditions of high temperature, high humidity, and light, moisture or water gradually penetrates the interior of the module. Under the action of light and heat, the acetic acid groups contained in the vinyl acetate-ethylene copolymer molecular chain break off from the main chain, generating acetic acid and olefin structures. This process is called deacetylation. In the presence of acetic acid, an electric potential difference is formed between the two metals of the tin-copper solder strip, and the metal with the lower potential will be corroded. Summary of the Invention

[0006] The present invention aims to provide a corrosion-resistant photovoltaic module material and a preparation method thereof. Zinc oxide nanoneedles are directionally grown on the surface of modified mica powder to obtain zinc oxide / mica powder, which is then treated with 3-aminopropyltriethoxysilane and grafted with 2-hydroxyaniline. Zinc oxide can be synergistically adsorbed on the metal surface with aniline to form a dense hydrophobic protective layer, which blocks the contact between the corrosive medium and the metal through a physical shielding effect, thereby inhibiting the electrochemical corrosion reaction.

[0007] The purpose of the present invention can be achieved through the following technical solutions: A method for preparing a corrosion-resistant photovoltaic module material comprises the following steps: Step 1: Zinc oxide nanoneedles are directionally grown on the surface of modified mica powder to obtain zinc oxide / mica powder, which is then treated with 3-aminopropyltriethoxysilane and grafted with 2-hydroxyaniline to obtain anti-corrosion modified mica powder. The mica powder is then carboxylated to obtain carboxylated modified nano mica powder, which is finally dispersed in polyvinyl alcohol-vinyl acetate copolymer to obtain a modified anti-corrosion emulsion.

[0008] Step 2: coating the modified anti-corrosion emulsion on the busbars and soldering strips of the photovoltaic cell to obtain a corrosion-resistant photovoltaic module material.

[0009] Furthermore, the preparation steps of the modified mica powder are as follows: Add crude mica powder, citric acid and deionized water into a reactor, stir at 80-90° C. and 400-500 r / min for 3-4 hours, filter, wash the filter cake with deionized water until the last washing liquid is neutral, and vacuum dry at 60-70° C. for 2-3 hours to obtain modified mica powder.

[0010] Furthermore, the usage ratio of the crude mica powder, citric acid and deionized water is 20-30 g:40-50 g:800-900 mL.

[0011] Furthermore, the preparation steps of zinc oxide / mica powder are as follows: Zinc acetate dihydrate powder and anhydrous ethanol are added to a reaction kettle, stirred at 20-25°C and 500-600 r / min for 1-2 hours, and then modified nano-mica powder, hexamethylenetetramine and deionized water are added. The mixture is heated to 80-90°C and stirred for 15-17 hours. The mixture is filtered, and the filter cake is washed with deionized water for 2-4 times and vacuum-dried at 60-70°C for 1-2 hours to obtain zinc oxide / mica powder.

[0012] Furthermore, the usage ratio of zinc acetate dihydrate powder, anhydrous ethanol, modified nano-mica powder, hexamethylenetetramine and deionized water is 50-60 g: 800-900 mL: 40-45 g: 12-14 g: 700-900 mL.

[0013] Furthermore, the preparation steps of the anti-corrosion modified mica powder are as follows: 2-Hydroxyaniline, 3-aminopropyltriethoxysilane, anhydrous ethanol and deionized water were added to a reaction kettle, stirred at 80-90°C and 400-500 r / min for 1-2 hours, and then zinc oxide / mica powder was added. The reaction was continued for 1-2 hours, filtered, and the filter cake was washed with deionized water 2-4 times and vacuum dried at 60-70°C for 1-2 hours to obtain anti-corrosion modified mica powder.

[0014] Furthermore, the usage ratio of 2-hydroxyaniline, 3-aminopropyltriethoxysilane, anhydrous ethanol, deionized water and zinc oxide / mica powder is 40-50 g: 20-30 mL: 180-200 mL: 200-220 mL: 50-60 g.

[0015] Furthermore, the preparation steps of carboxyl modified nano mica powder are as follows: Tetrahydrofuran and butanetetracarboxylic acid are added to a reaction kettle under nitrogen protection, and then N,N'-carbonyldiimidazole is added. The mixture is stirred at 20-25°C and 500-600 r / min for 5-6 hours, and then the anti-corrosion modified mica powder is added. The reaction is continued for 6-7 hours, and the mixture is centrifuged at 8000-9000 r / min for 2-3 minutes. The mixture is filtered, and the precipitate is washed with deionized water for 2-4 times and vacuum dried at 60-80°C for 1-2 hours to obtain carboxylated modified nano mica powder.

[0016] Furthermore, the usage ratio of tetrahydrofuran, butanetetracarboxylic acid, N,N'-carbonyldiimidazole and anti-corrosion modified mica powder is 200-220 mL: 5-6 g: 14-16 g: 20-30 g.

[0017] Furthermore, the preparation steps of the modified anti-corrosion emulsion are as follows: Add carboxylated modified nano mica powder and deionized water into a reactor, stir at 20-25°C and 500-600 r / min for 40-60 minutes, then add polyvinyl alcohol, heat to 90-100°C, stir until the material is completely dissolved, then cool to 40-45°C, add octylphenol polyoxyethylene ether, continue stirring and react for 30-40 minutes, then add vinyl acetate and potassium persulfate, heat to 65-70°C, keep warm for 1-2 hours, cool to 45-50°C, add sodium bicarbonate to adjust the pH value to 6-7, then add dibutyl phthalate, continue stirring for 40-60 minutes, cool naturally, and discharge to obtain a modified anti-corrosion emulsion.

[0018] Furthermore, the usage ratio of carboxylated modified nano mica powder, deionized water, polyvinyl alcohol, octylphenol polyoxyethylene ether, vinyl acetate, potassium persulfate and dibutyl phthalate is 200-220 g: 10-12 L: 1-2 L: 100-200 g: 2-3 L: 100-120 g: 100-130 g.

[0019] Beneficial effects of the present invention: 1. The corrosion-resistant photovoltaic module material prepared by the present invention is prepared by directionally growing zinc oxide nanoneedles on the surface of modified mica powder, then grafting 2-hydroxyaniline through 3-aminopropyltriethoxysilane treatment, and then carboxylation modification. Finally, the modified anti-corrosion emulsion is dispersed in a polyvinyl alcohol-vinyl acetate copolymer solution. The obtained modified anti-corrosion emulsion is coated on the photovoltaic cell sheet and has excellent corrosion resistance and light transmittance. It is not easy to age and the anti-corrosion emulsion coated on the surface is not easy to peel off.

[0020] 2. The zinc oxide / mica powder of the present invention uses modified mica powder as nucleation sites. In an alkaline environment, zinc oxide crystals preferentially grow along specific crystal planes to form nano-needle structures. The growth of zinc oxide nano-needles can increase the specific surface area and surface roughness of the modified mica. Zinc oxide can increase the corrosion resistance of photovoltaic module materials. Zinc oxide has certain photocatalytic activity, which causes it to produce active oxygen under light, decompose organic pollutants and inhibit the growth of microorganisms, thereby reducing biological corrosion. The high refractive index can absorb ultraviolet rays and reduce the aging of anti-corrosion emulsion coatings. In addition, the nano-needle structure of zinc oxide can increase the adhesion to the coating through a mechanical interlocking effect.

[0021] 3. The corrosion-resistant modified mica powder of the present invention is modified by grafting 3-aminopropyltriethoxysilane to graft 2-hydroxyaniline onto the surface of the zinc oxide / mica powder. The nitrogen atom in the amino group of the aniline carries a lone pair of electrons, which can form a coordination bond with the empty d orbital on the metal surface, allowing the aniline molecules to adsorb on the metal surface to form a dense hydrophobic protective layer. This process blocks the contact between the corrosive medium and the metal through a physical shielding effect, thereby inhibiting the electrochemical corrosion reaction.

[0022] 4. The surface of the carboxylated modified nano-mica powder of the present invention contains a large number of carboxyl groups that can form hydrogen bonds with the hydroxyl groups in the polyvinyl alcohol-vinyl acetate copolymer, thereby enhancing the compatibility between the filler and the polymer and reducing the intrusion of corrosive media caused by interface defects. DETAILED DESCRIPTION

[0023] 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 embodiments described 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 making creative efforts are within the scope of protection of the present invention.

[0024] Example 1: A method for preparing a corrosion-resistant photovoltaic module material, comprising the following steps: S1: Add 20 g of crude mica powder, 40 g of citric acid and 800 mL of deionized water into a reactor, stir at 80°C and 400 rpm for 3 h, filter, wash the filter cake with deionized water until the last washing liquid is neutral, and dry under vacuum at 60°C for 2 h to obtain modified mica powder.

[0025] S2: Add 50 g of zinc acetate dihydrate powder and 800 mL of anhydrous ethanol into a reactor, stir at 20°C and 500 r / min for 1 h, then add 40 g of modified mica powder, 12 g of hexamethylenetetramine and 700 mL of deionized water, heat to 80°C, continue stirring for 15 h, filter, wash the filter cake twice with deionized water, and vacuum dry at 60°C for 1 h to obtain zinc oxide / mica powder.

[0026] In an alkaline environment, zinc oxide crystals preferentially grow along specific crystal planes to form a nano-needle structure. The surface of the modified mica powder provides nucleation sites, promoting the directional growth of zinc oxide nanoneedles, constructing a micro / nano rough structure, and obtaining zinc oxide / mica powder. The zinc oxide nanoneedles directionally grown on the surface of the modified mica form a physical barrier and bind to the mica sheets.

[0027] S3: Add 40 g of 2-hydroxyaniline, 20 mL of 3-aminopropyltriethoxysilane, 180 mL of anhydrous ethanol and 200 mL of deionized water into a reactor, stir at 80°C and 400 r / min for 1 h, then add 50 g of zinc oxide / mica powder, continue the reaction for 1 h, filter, wash the filter cake twice with deionized water, and vacuum dry at 60°C for 1 h to obtain anti-corrosion modified mica powder.

[0028] S4: Add 200 mL of tetrahydrofuran and 5 g of butanetetracarboxylic acid into the reactor, under nitrogen protection, then add 14 g of N,N'-carbonyldiimidazole, stir at 20°C and 500 r / min for 5 hours, then add 20 g of anti-corrosion modified mica powder, continue the reaction for 6 hours, centrifuge at 8000 r / min for 2 minutes, filter, wash the precipitate twice with deionized water, and vacuum dry at 60°C for 1 hour to obtain carboxylated modified nano mica powder.

[0029] A butanetetracarboxylic acid with a carboxyl group activated is added, and the activated carboxyl group reacts with the amino group on the surface of the anti-corrosion modified nanomica, thereby introducing multiple carboxyl groups into the surface of the anti-corrosion modified nanomica to prepare the carboxylated modified nanomica.

[0030] S5: Add 200g of carboxylated modified nano-mica powder and 10L of deionized water into the reactor, stir for 40min at 20℃ and 500r / min, then add 1L of polyvinyl alcohol, heat to 90℃, stir until the material is completely dissolved, then cool to 40℃, add 100g of emulsifier octylphenol polyoxyethylene ether, continue stirring and react for 30min, then add 2L of vinyl acetate and 100g of initiator potassium persulfate, heat to 65℃, keep warm for 1h, cool to 45℃, add sodium bicarbonate to adjust the pH to 6, then add 100g of plasticizer dibutyl phthalate, continue stirring for 40min, cool naturally, and discharge to obtain a modified anti-corrosion emulsion.

[0031] S6: coating the modified anti-corrosion emulsion on the busbars and solder strip surfaces of the photovoltaic cell to obtain a corrosion-resistant photovoltaic module material.

[0032] Example 2: A method for preparing a corrosion-resistant photovoltaic module material, comprising the following steps: S1: Add 25 g of crude mica powder, 45 g of citric acid and 850 mL of deionized water into a reactor, stir at 85°C and 450 r / min for 3.5 h, filter, wash the filter cake with deionized water until the last washing liquid is neutral, and vacuum dry at 65°C for 2.5 h to obtain modified mica powder.

[0033] S2: Add 55 g of zinc acetate dihydrate powder and 850 mL of anhydrous ethanol into a reactor, stir at 22.5°C and 550 r / min for 1.5 h, then add 42.5 g of modified mica powder, 13 g of hexamethylenetetramine and 800 mL of deionized water, heat to 85°C, continue stirring for 16 h, filter, wash the filter cake with deionized water three times, and vacuum dry at 65°C for 1.5 h to obtain zinc oxide / mica powder.

[0034] S3: Add 45 g of 2-hydroxyaniline, 25 mL of 3-aminopropyltriethoxysilane, 190 mL of anhydrous ethanol and 210 mL of deionized water into a reactor, stir at 85°C and 450 r / min for 1.5 h, then add 55 g of zinc oxide / mica powder, continue the reaction for 1.5 h, filter, wash the filter cake with deionized water three times, and vacuum dry at 65°C for 1.5 h to obtain anti-corrosion modified mica powder.

[0035] S4: Add 210 mL of tetrahydrofuran and 5.5 g of butanetetracarboxylic acid into the reactor under nitrogen protection, then add 15 g of N,N'-carbonyldiimidazole, stir at 22.5 ° C and 550 r / min for 5.5 hours, then add 25 g of anti-corrosion modified mica powder, continue to react for 6.5 hours, centrifuge at 8500 r / min for 2.5 minutes, filter, wash the precipitate with deionized water three times, and vacuum dry at 70 ° C for 1.5 hours to obtain carboxylated modified nano mica powder.

[0036] S5: Add 210g of carboxylated modified nano mica powder and 11L of deionized water into the reactor, stir for 50min at 22.5℃ and 550r / min, then add 1.5L of polyvinyl alcohol, heat to 95℃, stir until the material is completely dissolved, then cool to 42.5℃, add 150g of emulsifier octylphenol polyoxyethylene ether, continue stirring and react for 35min, then add 2.5L of vinyl acetate and 110g of initiator potassium persulfate, heat to 67.5℃, keep warm for 1.5h, cool to 47.5℃, add sodium bicarbonate to adjust the pH to 6.5, then add 115g of plasticizer dibutyl phthalate, continue stirring for 50min, cool naturally, and discharge to obtain a modified anti-corrosion emulsion.

[0037] S6: coating the modified anti-corrosion emulsion on the busbars and solder strip surfaces of the photovoltaic cell to obtain a corrosion-resistant photovoltaic module material.

[0038] Example 3: A method for preparing a corrosion-resistant photovoltaic module material, comprising the following steps: S1: Add 30 g of crude mica powder, 50 g of citric acid and 900 mL of deionized water into a reactor, stir at 90°C and 500 rpm for 4 h, filter, wash the filter cake with deionized water until the last washing liquid is neutral, and vacuum dry at 70°C for 3 h to obtain modified mica powder.

[0039] S2: Add 60 g of zinc acetate dihydrate powder and 900 mL of anhydrous ethanol into a reactor, stir at 25°C and 600 r / min for 2 h, then add 45 g of modified mica powder, 14 g of hexamethylenetetramine and 900 mL of deionized water, heat to 90°C, continue stirring for 17 h, filter, wash the filter cake with deionized water 4 times, and vacuum dry at 70°C for 2 h to obtain zinc oxide / mica powder.

[0040] S3: Add 50 g of 2-hydroxyaniline, 30 mL of 3-aminopropyltriethoxysilane, 200 mL of anhydrous ethanol and 220 mL of deionized water into a reactor, stir at 90°C and 500 r / min for 2 h, then add 60 g of zinc oxide / mica powder, continue the reaction for 2 h, filter, wash the filter cake with deionized water 4 times, and vacuum dry at 70°C for 2 h to obtain anti-corrosion modified mica powder.

[0041] S4: Add 220 mL of tetrahydrofuran and 6 g of butanetetracarboxylic acid into the reactor, and under nitrogen protection, then add 16 g of N,N'-carbonyldiimidazole, stir at 25 ° C and 600 r / min for 6 hours, then add 30 g of anti-corrosion modified mica powder, continue to react for 7 hours, centrifuge at 9000 r / min for 3 minutes, filter, wash the precipitate with deionized water 4 times, and vacuum dry at 80 ° C for 2 hours to obtain carboxylated modified nano mica powder.

[0042] S5: Add 220g of carboxylated modified nano-mica powder and 12L of deionized water into the reactor, stir for 60min at 25℃ and 600r / min, then add 2L of polyvinyl alcohol, heat to 100℃, stir until the material is completely dissolved, then cool to 45℃, add 200g of emulsifier octylphenol polyoxyethylene ether, continue stirring and react for 40min, then add 3L of vinyl acetate and 120g of initiator potassium persulfate, heat to 70℃, keep warm for 2h, cool to 50℃, add sodium bicarbonate to adjust the pH to 7, then add 130g of plasticizer dibutyl phthalate, continue stirring for 60min, cool naturally, and discharge to obtain a modified anti-corrosion emulsion.

[0043] S6: coating the modified anti-corrosion emulsion on the busbars and solder strip surfaces of the photovoltaic cell to obtain a corrosion-resistant photovoltaic module material.

[0044] Comparative Example 1: Based on Example 3, without step S2, the zinc oxide / mica powder in step S3 is replaced by the modified mica powder in step S1, and the other steps remain unchanged to obtain a corrosion-resistant photovoltaic module material.

[0045] Comparative Example 2: Based on Example 3, the anti-corrosion modified mica powder in step S4 is replaced by the zinc oxide / mica powder in step S2, and the other steps remain unchanged to obtain a corrosion-resistant photovoltaic module material.

[0046] Comparative Example 3: Based on Example 3, the carboxyl modified nano mica powder in step S5 is replaced by the anti-corrosion modified mica powder in step S3, and the other steps remain unchanged to obtain a corrosion-resistant photovoltaic module material.

[0047] The corrosion-resistant photovoltaic module materials obtained in Examples 1-3 and Comparative Examples 1-3 were prepared into corrosion-resistant photovoltaic modules and their performance was tested. A low melt index EVA resin material layer and a high melt index EVA resin material layer were co-extruded into a double-layer or multi-layer encapsulation film to obtain an EVA photovoltaic encapsulation film. The modified corrosion-resistant emulsion was applied to the busbars and welding ribbon surfaces of the photovoltaic cell to obtain a corrosion-resistant photovoltaic module material. The photovoltaic front panel, the EVA photovoltaic encapsulation film, the corrosion-resistant photovoltaic module material, and the photovoltaic back panel were stacked in sequence and heated and laminated to obtain a corrosion-resistant photovoltaic module. The results are shown in Table 1: 1. Appearance corrosion test: Electroluminescence tracking is used to observe the diffusion of fillers in the anti-corrosion coating of the anti-corrosion photovoltaic module and the appearance corrosion of the welding ribbons and bus bars of the anti-corrosion photovoltaic module after 2000 hours of high temperature and high humidity aging (85℃, 85%RH).

[0048] 2. Transmittance test: The anti-corrosion photovoltaic modules of Examples 1-3 and Comparative Examples 1-3 were subjected to a transmittance test after lamination. The transmittance was measured in accordance with GB / T24102008. The transmittance of the EVA photovoltaic encapsulation film at 700-400nm was measured using a UV-visible spectrophotometer. The transmittance after aging refers to the transmittance of the anti-corrosion photovoltaic module after 2000 hours of high-temperature and high-humidity aging (85°C, 85% RH).

[0049] 3. Salt spray test: Test according to the method of ASTM B117.

[0050] 4. Impact test: Test according to ISO6272-80.

[0051] Table 1 Corrosion-resistant photovoltaic module materials project Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Appearance corrosion No corrosion No corrosion No corrosion corrosion corrosion No corrosion Light transmittance (%) 92.85 92.99 93.21 93.32 93.36 91.26 Transmittance after aging (%) 92.68 92.86 93.01 78.25 79.15 85.43 Salt spray test No blistering, no red rust, no cracking No blistering, no red rust, no cracking No blistering, no red rust, no cracking Blistering, red embroidery, cracking Blistering, red embroidery, cracking No blistering, no red rust, no cracking Impact resistance (kg·cm) 118 123 129 66 87 71 Adhesion (MPa) 10.6 11.2 11.9 6.8 9.8 6.3 As can be seen from Table 1, the photovoltaic module materials prepared in Examples 1-3 are significantly better than those in the comparative example in terms of appearance corrosion, light transmittance, light transmittance after aging, salt spray test, adhesion and impact resistance. The decrease in light transmittance after aging of Examples 1-3 is smaller than that of the comparative example. The treatment of Comparative Example 1 and Comparative Example 2 causes a significant decrease in performance in the aging experiment, indicating that the photovoltaic module material prepared in the present invention has excellent anti-corrosion performance, excellent light transmittance, is not easy to age, and the anti-corrosion emulsion coated on the surface is not easy to peel off.

[0052] In Comparative Example 1, the zinc oxide / mica powder is replaced with modified mica powder, and zinc oxide nanoneedles are directionally grown on the surface of the modified mica powder. The growth of zinc oxide nanoneedles can increase the specific surface area and surface roughness of the modified mica. Zinc oxide can increase the corrosion resistance of photovoltaic module materials. Zinc oxide has certain photocatalytic activity, which enables it to produce active oxygen under light, decompose organic pollutants and inhibit the growth of microorganisms, thereby reducing biological corrosion. The high refractive index can absorb ultraviolet rays and reduce the aging of the anti-corrosion emulsion coating. The nanoneedle structure of zinc oxide can increase the adhesion to the coating through a mechanical interlocking effect.

[0053] In Comparative Example 2, the anti-corrosion modified mica powder was replaced with zinc oxide / mica powder, and 2-hydroxyaniline was grafted onto the surface of the zinc oxide / mica powder through 3-aminopropyltriethoxysilane grafting modification. The nitrogen atom in the aniline amino group carries a lone pair of electrons, which can form a coordination bond with the empty d orbital on the metal surface, causing the aniline molecules to adsorb on the metal surface to form a dense hydrophobic protective layer. This process blocks the contact between the corrosive medium and the metal through physical shielding, thereby inhibiting the electrochemical corrosion reaction.

[0054] In Comparative Example 3, the carboxylated modified nano mica powder is replaced with anti-corrosion modified mica powder. The surface of the carboxylated modified nano mica powder contains a large number of carboxyl groups that can form hydrogen bonds with the hydroxyl groups in the polyvinyl alcohol-vinyl acetate copolymer, thereby enhancing the compatibility between the filler and the polymer and reducing the intrusion of corrosive media caused by interface defects.

[0055] While the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations can be made to the embodiments without departing from the principles and spirit of the invention.

Claims

1. A method for preparing a corrosion-resistant photovoltaic module material, characterized in that: The steps include: Step 1: zinc oxide nanoneedles are directionally grown on the surface of modified mica powder to obtain zinc oxide / mica powder, which is then treated with 3-aminopropyltriethoxysilane and grafted with 2-hydroxyaniline to obtain anti-corrosion modified mica powder, which is then carboxylated to obtain carboxylated modified nano mica powder, which is finally dispersed in a polyvinyl alcohol-vinyl acetate copolymer solution to obtain a modified anti-corrosion emulsion; Step 2: coating the modified anti-corrosion emulsion on the busbars and soldering strips of the photovoltaic cell to obtain a corrosion-resistant photovoltaic module material.

2. The method for preparing a corrosion-resistant photovoltaic module material according to claim 1, characterized in that: The preparation steps of the modified mica powder are as follows: Add crude mica powder, citric acid and deionized water into a reactor, stir at 80-90°C and 400-500 r / min for 3-4 hours, filter, wash until neutral, and vacuum dry to obtain modified mica powder; The usage ratio of the crude mica powder, citric acid and deionized water is 20-30 g: 40-50 g: 800-900 mL.

3. The method for preparing a corrosion-resistant photovoltaic module material according to claim 1, characterized in that: The preparation steps of the zinc oxide / mica powder are as follows: Add zinc acetate dihydrate powder and anhydrous ethanol to a reaction kettle, stir at 20-25°C and 500-600 r / min for 1-2 hours, then add modified nano-mica powder, hexamethylenetetramine and deionized water, heat to 80-90°C, continue stirring for 15-17 hours, filter, wash, and vacuum dry to obtain zinc oxide / mica powder; The usage ratio of the zinc acetate dihydrate powder, anhydrous ethanol, modified nano-mica powder, hexamethylenetetramine and deionized water is 50-60 g: 800-900 mL: 40-45 g: 12-14 g: 700-900 mL.

4. The method for preparing a corrosion-resistant photovoltaic module material according to claim 1, characterized in that: The preparation steps of the anti-corrosion modified mica powder are as follows: 2-Hydroxyaniline, 3-aminopropyltriethoxysilane, anhydrous ethanol and deionized water were added to a reaction kettle, stirred at 80-90°C and 400-500 r / min for 1-2 hours, and then zinc oxide / mica powder was added, and the reaction was continued for 1-2 hours. The mixture was filtered, washed and vacuum dried to obtain anti-corrosion modified mica powder.

5. The method for preparing a corrosion-resistant photovoltaic module material according to claim 4, characterized in that: The usage ratio of the 2-hydroxyaniline, 3-aminopropyltriethoxysilane, anhydrous ethanol, deionized water and zinc oxide / mica powder is 40-50 g: 20-30 mL: 180-200 mL: 200-220 mL: 50-60 g.

6. The method for preparing a corrosion-resistant photovoltaic module material according to claim 1, characterized in that: The preparation steps of the carboxyl modified nano mica powder are as follows: Tetrahydrofuran and butanetetracarboxylic acid are added to a reaction kettle under nitrogen protection, and then N,N'-carbonyldiimidazole is added. The mixture is stirred at 20-25°C and 500-600 r / min for 5-6 hours, and then the anti-corrosion modified mica powder is added. The reaction is continued for 6-7 hours, and the mixture is centrifuged at 8000-9000 r / min for 2-3 minutes. The mixture is filtered, washed, and vacuum dried to obtain carboxylated modified nano mica powder.

7. The method for preparing a corrosion-resistant photovoltaic module material according to claim 6, characterized in that: The usage ratio of tetrahydrofuran, butanetetracarboxylic acid, N,N'-carbonyldiimidazole and anti-corrosion modified mica powder is 200-220 mL: 5-6 g: 14-16 g: 20-30 g.

8. The method for preparing a corrosion-resistant photovoltaic module material according to claim 1, characterized in that: The preparation steps of the modified anti-corrosion emulsion are as follows: Add carboxylated modified nano mica powder and deionized water into a reactor, stir at 20-25°C and 500-600 r / min for 40-60 minutes, then add polyvinyl alcohol, heat to 90-100°C, stir until the material is completely dissolved, then cool to 40-45°C, add octylphenol polyoxyethylene ether, continue stirring and react for 30-40 minutes, then add vinyl acetate and potassium persulfate, heat to 65-70°C, keep warm for 1-2 hours, cool to 45-50°C, add sodium bicarbonate to adjust the pH value to 6-7, then add dibutyl phthalate, continue stirring for 40-60 minutes, cool naturally, and discharge to obtain a modified anti-corrosion emulsion.

9. The method for preparing a corrosion-resistant photovoltaic module material according to claim 8, characterized in that: The usage ratio of the carboxylated modified nano mica powder, deionized water, polyvinyl alcohol, octylphenol polyoxyethylene ether, vinyl acetate, potassium persulfate and dibutyl phthalate is 200-220g:10-12L:1-2L:100-200g:2-3L:100-120g:100-130g.

10. A corrosion-resistant photovoltaic module material, characterized in that: Prepared by the preparation method according to any one of claims 1 to 9.