CN107383949B - Wear-resistant self-cleaning photovoltaic glass anti-reflection hydrophobic coating liquid and preparation method thereof - Google Patents
Wear-resistant self-cleaning photovoltaic glass anti-reflection hydrophobic coating liquid and preparation method thereof Download PDFInfo
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- CN107383949B CN107383949B CN201710599884.0A CN201710599884A CN107383949B CN 107383949 B CN107383949 B CN 107383949B CN 201710599884 A CN201710599884 A CN 201710599884A CN 107383949 B CN107383949 B CN 107383949B
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- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D1/00—Coating compositions, e.g. paints, varnishes or lacquers, based on inorganic substances
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
- C09D5/16—Antifouling paints; Underwater paints
- C09D5/1687—Use of special additives
Abstract
The invention relates to a surface hydrophobing agent, in particular to an anti-reflection hydrophobic coating liquid for wear-resistant self-cleaning photovoltaic glass. According to the preparation method S1 of the wear-resistant self-cleaning photovoltaic glass antireflection hydrophobic coating liquid, perfluoroalkylsilane and tetraethyl orthosilicate are dissolved in an organic solvent, an acid catalyst is added for hydrolysis, and the acid catalyst is removed to obtain an acid catalytic reaction system; s2, dissolving perfluoroalkyl silane and tetraethyl orthosilicate in an organic solvent, adding an alkali catalyst for hydrolysis, removing the alkali catalyst, and aging to obtain an alkali catalytic reaction system; the organic solvent is the same as the organic solvent in step S1; s3, mixing the acid catalytic reaction system in the step S1 and the alkali catalytic reaction system in the step S2, and stirring uniformly to obtain the wear-resistant self-cleaning photovoltaic glass antireflection hydrophobic coating liquid. The wear-resistant self-cleaning photovoltaic glass antireflection hydrophobic coating liquid provided by the invention can obtain satisfactory light transmittance and wear resistance under the condition of good hydrophobicity.
Description
Technical Field
The invention relates to a surface hydrophobing agent, in particular to an anti-reflection hydrophobic coating liquid for wear-resistant self-cleaning photovoltaic glass.
Background
As the solar cell module is continuously improved by people, the photoelectric conversion rate of the silicon wafer in the solar cell module reaches the limit on the current process manufacturing level, and the problem that the photoelectric conversion rate of the solar cell is required to be improved is solved. Meanwhile, the working places of the solar cells are mostly arranged outdoors or in deserts with severe environments, so that the surfaces of the solar cell modules are easy to be dirty and difficult to clean after being dirty. The photovoltaic glass antireflection film is a coating material which is coated on the surface of the cover plate glass of the photovoltaic module to improve the solar light transmittance so as to increase the utilization efficiency of the photovoltaic module on light energy, so that the transmittance performance of the antireflection film has great influence on the generated energy in the power generation process of the photovoltaic module.
At present, the main methods for the hydrophobic photovoltaic antireflection film technology are as follows: the high-temperature sintering method is adopted, and the preparation process of the photovoltaic glass antireflection film prepared by the method has extremely high energy consumption; the sol-gel method normal temperature curing film has a surface looser than that of an acid-catalyzed film layer for an alkali-catalyzed film layer, so that the light transmittance is improved, but has the characteristic of poor fatality, and the service life of the sol-gel method normal temperature curing film is not as long as that of the acid-catalyzed film layer. The membrane layer cured at normal temperature by acid catalysis has improved compactness and prolonged service life, but the light transmittance is inferior to that of the alkali catalysis membrane layer, and the hydrophobic angle is far inferior to that of the alkali catalysis membrane layer, so that the self-cleaning property of the membrane layer is reduced. The acid-base catalysis method is used in combination, so that the film layer is firmly determined by the characteristic of acid-base catalysis hydrophobicity, the characteristics of higher hydrophobicity angle and extremely high light transmittance of the alkali catalysis coating are kept, and the weather resistance of the acid catalysis hydrophobic film is also realized.
Disclosure of Invention
The invention provides a wear-resistant self-cleaning photovoltaic glass anti-reflection hydrophobic coating liquid and a preparation method thereof, and the purpose of the invention can be realized by the following technical scheme:
the preparation method of the wear-resistant self-cleaning photovoltaic glass anti-reflection hydrophobic coating liquid provided by the invention comprises the following steps:
s1, dissolving perfluoroalkyl silane and tetraethyl orthosilicate in an organic solvent, adding an acid catalyst for hydrolysis, and removing the acid catalyst to obtain an acid catalytic reaction system; the molar ratio of the perfluoroalkylsilane to the tetraethyl orthosilicate is 1:0.01-10, and the total weight of the perfluoroalkylsilane and the tetraethyl orthosilicate is 1-6% of the weight of the organic solvent;
s2, dissolving perfluoroalkyl silane and tetraethyl orthosilicate in an organic solvent, adding an alkali catalyst for hydrolysis, removing the alkali catalyst, and aging to obtain an alkali catalytic reaction system; the molar ratio of the perfluoroalkylsilane to the tetraethyl orthosilicate is 1:0.01-10, and the total weight of the perfluoroalkylsilane and the tetraethyl orthosilicate is 1-6% of the solvent; the organic solvent is the same as the organic solvent in step S1; the aging may be closed aging at room temperature for 7 days.
S3, mixing the acid catalysis reaction system in the step S1 and the base catalysis reaction system in the step S2 according to the volume ratio of 1: 1-2, and uniformly stirring to obtain the wear-resistant self-cleaning photovoltaic glass anti-reflection hydrophobic coating liquid.
Wherein the perfluoroalkylsilane is heptadecafluorodecyltrimethoxysilane or tridecafluorooctyltrimethoxysilane in steps S1 and S2.
Wherein, the organic solvent in the step S1 is one or more of ethanol, methanol, isopropanol, n-butanol or acetone.
Wherein, the acid catalyst in the step S1 is one or more of hydrochloric acid, nitric acid and acetic acid.
Wherein the hydrolysis method in the step S1 is to adjust the pH to 2-4 by acid catalyst and heat at 45-55 ℃ for 2-4 hours.
Wherein the alkali catalyst in step S2 is ammonia water. The preferable mass percentage is 15-30%.
Wherein, the hydrolysis method in the step S2 is to adjust the PH to 9-11 and 20-30 ℃ by using an alkali catalyst and stir for 4-6 hours.
The wear-resistant self-cleaning photovoltaic glass anti-reflection hydrophobic coating liquid prepared by any one of the preparation methods.
The application method of the wear-resistant self-cleaning photovoltaic glass antireflection hydrophobic coating liquid provided by the invention can adopt coating methods such as spraying, wiping, rolling and the like, and preferably adopts the steps of spraying a mixed system on a substrate (such as photovoltaic glass) and curing for 24H at normal temperature.
Compared with the prior art, the invention has the beneficial effects that:
(1) the defect that photovoltaic glass is easy to stain is solved, dirt is difficult to accumulate on the surface of the glass due to low surface energy, the glass is easier to keep clean, and the light transmittance is prevented from being reduced.
(2) The light transmittance of the original ultra-white photovoltaic glass is improved to more than 96%.
(3) Can be cured at normal temperature, and can obtain an easy-to-clean and anti-reflection coating without a complex high-temperature sintering process.
(4) Adopts green environment-friendly solvent and does not contain benzene.
(5) The invention combines the advantages of the two coatings to ensure that the coating obtains more satisfactory light transmittance and wear resistance
(6) Simple reaction process and mild conditions
(7) The construction method is simple, and the coating methods such as spraying, wiping, rolling and the like can be adopted
Detailed Description
The invention will now be further illustrated by reference to the following examples:
example 1
A: acid-catalyzed gelling: dissolving 3 g of heptadecafluorodecyltrimethoxysilane and 1.5g of tetraethyl orthosilicate in 80 g of ethanol, adding 36% hydrochloric acid, adjusting the pH to 3, heating at 50 ℃ for 3 hours, stopping stirring, heating to 40 ℃, and vacuumizing to remove hydrochloric acid
B: base-catalyzed gel: dissolving 3 g of heptadecafluorodecyltrimethoxysilane and 1.5g of tetraethyl orthosilicate in 80 g of ethanol, slowly adding 25% ammonia water at 25 ℃, adjusting the pH to 10, stirring for 5 hours, heating to 40 ℃, vacuumizing to remove ammonia gas, sealing and aging at room temperature for 7 days
C: slowly adding 1 volume of the base catalysis gel into 1 volume of the acid catalysis gel while stirring, and continuously stirring for 3min after the addition is finished.
D: spraying the mixed system on ultra-white glass, naturally leveling, and curing at normal temperature for 24H test
Example 2
A: acid-catalyzed gelling: dissolving 3 g of tridecafluorooctyltrimethoxysilane and 1.5g of tetraethyl orthosilicate in 80 g of ethanol, adding 36% hydrochloric acid, adjusting the pH to 3, heating to 50 ℃ for 3 hours, stopping stirring, heating to 40 ℃, and vacuumizing to remove acetic acid
B: base-catalyzed gel: dissolving 3 g of heptadecafluorodecyltrimethoxysilane and 1.5g of tetraethyl orthosilicate in 80 g of ethanol, slowly adding 25% ammonia water at 25 ℃, adjusting the pH to 10, stirring for 5 hours, heating to 40 ℃, vacuumizing to remove ammonia gas, sealing and aging at room temperature for 7 days
C: slowly adding 1 volume of the base catalysis gel into 1 volume of the acid catalysis gel while stirring, and continuously stirring for 3min after the addition is finished.
D: spraying the mixed system on ultra-white glass, and testing by curing at normal temperature for 24H
Example 3
A: acid-catalyzed gelling: dissolving 3 g of heptadecafluorodecyltrimethoxysilane and 1.5g of tetraethyl orthosilicate in 80 g of ethanol, adding 36% nitric acid, adjusting the pH to 3, heating at 50 ℃ for 3 hours, stopping stirring, heating to 40 ℃, and vacuumizing to remove acetic acid
B: base-catalyzed gel: dissolving 3 g of tridecafluorooctyltrimethoxysilane and 1.5g of tetraethyl orthosilicate in 80 g of ethanol, slowly adding 25% ammonia water at 25 ℃, adjusting the pH to 10, stirring for 5 hours, heating to 40 ℃, vacuumizing to remove ammonia gas, sealing and aging at room temperature for 7 days
C: slowly adding 1 volume of the base catalysis gel into 1 volume of the acid catalysis gel while stirring, and continuously stirring for 3min after the addition is finished.
D: spraying the mixed system on ultra-white glass, and testing by curing at normal temperature for 24H
Example 4
A: acid-catalyzed gelling: dissolving 3 g of tridecafluorooctyltrimethoxysilane and 1.5g of tetraethyl orthosilicate in 80 g of ethanol, adding 36 percent nitric acid, adjusting the pH to 3, heating to 50 ℃ for 3 hours, stopping stirring, heating to 40 ℃, and vacuumizing to remove acetic acid
B: base-catalyzed gel: dissolving 3 g of tridecafluorooctyltrimethoxysilane and 1.5g of tetraethyl orthosilicate in 80 g of ethanol, slowly adding 25% ammonia water at 25 ℃, adjusting the pH to 10, stirring for 5 hours, heating to 40 ℃, vacuumizing to remove ammonia gas, sealing and aging at room temperature for 7 days
C: slowly adding 2 volumes of base catalysis gel into 1 volume of acid catalysis gel while stirring, and continuously stirring for 3min after the addition is finished.
D: spraying the mixed system on ultra-white glass, and testing by curing at normal temperature for 24H
Comparative example 1
Dissolving 3 g of tridecafluorooctyltrimethoxysilane and 1.5g of tetraethyl orthosilicate in 80 g of ethanol, adding 36 percent nitric acid, adjusting the pH to 3, heating to 50 ℃ for 3 hours, stopping stirring, heating to 40 ℃, and vacuumizing to remove acetic acid
Spraying the mixture on ultra-white glass, naturally leveling, and curing at normal temperature for 24H test
Comparative example 2
Dissolving 3 g of tridecafluorooctyltrimethoxysilane and 1.5g of tetraethyl orthosilicate in 80 g of ethanol, slowly adding 25% ammonia water at 25 ℃, adjusting the pH to 10, stirring for 5 hours, heating to 40 ℃, vacuumizing to remove ammonia gas, aging for 7 days for later use
Spraying the mixture on ultra-white glass, naturally leveling, and curing at normal temperature for 24H test
And (3) wear resistance test: under the condition that the sponge is completely wetted, the change rate of the hydrophobic angle of the coated glass after the load 1N rubs 40000 back and forth on the coated glass
It will be evident to those skilled in the art and having the benefit of the foregoing description that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in many different forms and that the above-described embodiments are therefore illustrative and not restrictive. Scope of the invention the appended claims are to be accorded the meaning and range of equivalents for the embodiment.
Claims (5)
1. A preparation method of a wear-resistant self-cleaning photovoltaic glass anti-reflection hydrophobic coating liquid is characterized by comprising the following steps:
s1, dissolving perfluoroalkyl silane and tetraethyl orthosilicate in an organic solvent, adding an acid catalyst for hydrolysis, and removing the acid catalyst to obtain an acid catalytic reaction system; the molar ratio of the perfluoroalkylsilane to the tetraethyl orthosilicate is 1:0.01, and the total weight of the perfluoroalkylsilane and the tetraethyl orthosilicate is 1-6% of the weight of the organic solvent; the hydrolysis method comprises adjusting pH to 2-4 with acid catalyst, and heating at 45-55 deg.C for 2-4 hr;
s2, dissolving perfluoroalkyl silane and tetraethyl orthosilicate in an organic solvent, adding an alkali catalyst for hydrolysis, removing the alkali catalyst, and aging to obtain an alkali catalytic reaction system; the molar ratio of the perfluoroalkylsilane to the tetraethyl orthosilicate is 1:0.01, and the total weight of the perfluoroalkylsilane and the tetraethyl orthosilicate is 1-6% of the weight of the organic solvent; the organic solvent is the same as the organic solvent in step S1; the hydrolysis method comprises the steps of adjusting the pH value to 9-11 by using an alkali catalyst, and stirring for 4-6 hours at the temperature of 20-30 ℃;
s3, mixing the acid catalysis reaction system in the step S1 and the base catalysis reaction system in the step S2 according to the volume ratio of 1: 1-2, mixing and uniformly stirring to obtain the wear-resistant self-cleaning photovoltaic glass anti-reflection hydrophobic coating liquid;
the application method of the wear-resistant self-cleaning photovoltaic glass anti-reflection hydrophobic coating liquid comprises the steps of spraying the mixed system on a substrate, and curing for 24 hours at normal temperature.
2. The method for preparing the wear-resistant self-cleaning photovoltaic glass antireflection hydrophobic coating liquid according to claim 1, wherein the perfluoroalkylsilane is heptadecafluorodecyltrimethoxysilane or tridecafluorooctyltrimethoxysilane in steps S1 and S2.
3. The preparation method of the wear-resistant self-cleaning photovoltaic glass antireflection hydrophobic coating liquid according to claim 1, wherein the organic solvent in step S1 is one or more of ethanol, methanol, isopropanol, n-butanol or acetone.
4. The preparation method of the wear-resistant self-cleaning photovoltaic glass antireflection hydrophobic coating liquid according to claim 1, wherein the acid catalyst in step S1 is one or more of hydrochloric acid, nitric acid and acetic acid.
5. The preparation method of the wear-resistant self-cleaning photovoltaic glass antireflection hydrophobic coating liquid according to claim 1, wherein the alkali catalyst in step S2 is ammonia water.
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CN108250859A (en) * | 2018-02-12 | 2018-07-06 | 揭阳市宏光镀膜玻璃有限公司 | A kind of hydrophobic self-cleaning glass film liquid and preparation method thereof |
CN108546429A (en) * | 2018-04-03 | 2018-09-18 | 广州保赐利化工有限公司 | A kind of double open coat liquid of grease for vehicle glass |
CN109181537B (en) * | 2018-07-16 | 2020-11-06 | 武汉疏能新材料有限公司 | Super-amphiphobic SiO2Preparation method and application of nano functional liquid |
CN110724256A (en) * | 2019-10-31 | 2020-01-24 | 中国科学院兰州化学物理研究所 | Hydrophobic treatment agent, preparation method and application thereof, wear-resistant self-cleaning glass and preparation method thereof |
CN112479598B (en) * | 2020-12-09 | 2022-05-17 | 中建材玻璃新材料研究院集团有限公司 | Photovoltaic glass processing device and processing method |
CN112608038B (en) * | 2020-12-23 | 2022-05-20 | 苏州中来光伏新材股份有限公司 | Antireflection and permeation-increasing liquid for repairing photovoltaic module glass and preparation method thereof |
CN112980321B (en) * | 2021-04-21 | 2021-08-10 | 广东威凯表面技术有限公司 | Preparation method of easy-to-clean nano sterilizing coating liquid |
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CN105440747B (en) * | 2016-01-26 | 2018-05-08 | 东南大学 | A kind of super-hydrophobic nano coating, production method and the coating of super-hydrophobic nano coating |
CN106283151B (en) * | 2016-08-30 | 2018-05-22 | 浙江大学 | A kind of preparation method of wear-resisting based superhydrophobic thin films |
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CN1712478A (en) * | 2004-06-14 | 2005-12-28 | 中国科学院过程工程研究所 | Nanometer multifunctional composite thin-membrane, its production and use |
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