Anti-reflection liquid with self-repairing function, preparation method of anti-reflection liquid and organic-inorganic hybrid coating prepared from anti-reflection liquid

Abstract

The invention relates to the technical field of photovoltaic glass coatings, and discloses an anti-reflection liquid with a self-repairing function, a preparation method of the anti-reflection liquid and an organic-inorganic hybrid coating prepared from the anti-reflection liquid. The polyurethane-silicon dioxide composite resin with a disulfide bond structure is introduced, so that an automatic repairing function of the coating when the coating is damaged by slight scratches or cracks and the like is realized; by adopting an in-situ hybridization strategy, SiO2 particles are uniformly generated and stably dispersed in a polyurethane matrix to form a compact and synergistically enhanced composite network structure, so that excellent optical performance is maintained while functionality is achieved, and the power generation efficiency of a photovoltaic module is favorably improved; by adjusting the hydrophobicity of the surface of the coating, the super-hydrophobic effect is achieved; the preparation method is mild in process conditions.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic glass coating technology, specifically to a self-healing antireflective liquid, its preparation method, and an organic-inorganic hybrid coating prepared therefrom. Background Technology

[0002] With the development of the photovoltaic industry, photovoltaic glass, as an important component of modules, directly affects the conversion efficiency of photovoltaic modules due to its light transmittance and surface cleanliness. To improve the light transmittance of photovoltaic glass and achieve surface self-cleaning, researchers have developed a variety of anti-reflective and self-cleaning coatings, such as superhydrophobic coatings, superhydrophilic coatings, and liquid-lubricated superslip coatings.

[0003] However, existing coatings generally suffer from poor weather resistance, susceptibility to damage, and limited service life. Especially in outdoor environments, exposed to wind, sand, rain, and ultraviolet radiation, coatings are prone to scratches or degradation, leading to a significant decrease in their anti-reflective and self-cleaning functions. Therefore, developing an anti-reflective and self-cleaning coating with self-healing capabilities is crucial for improving the service life and performance stability of coatings. Summary of the Invention

[0004] The purpose of this invention is to overcome the problems existing in the prior art and provide a self-healing anti-reflective liquid, its preparation method, and an organic-inorganic hybrid coating prepared therefrom.

[0005] The specific objectives of this invention are as follows:

[0006] (1) Improve the environmental adaptability and lifespan of the coating: By introducing a self-healing system, the coating can spontaneously repair itself under specific external stimuli (such as heat, light or moisture) after being damaged by minor scratches, cracks or other damage, which significantly improves durability and ease of maintenance.

[0007] (2) It has both high light transmittance and self-cleaning properties: Through nanostructure design and hydrophilicity-hydrophobicity regulation, the coating surface has good anti-reflection effect (>96%) and self-cleaning ability;

[0008] (3) Provides an in-situ synthesized organic-inorganic hybrid coating system to achieve structural synergy and functional integration.

[0009] To achieve the above objectives, the first aspect of the present invention provides a method for preparing a self-healing, permeability-enhancing liquid, wherein the method includes the following steps:

[0010] (1) In the presence of a first organic solvent and a first catalyst, polytetrahydrofuran ether diol and isoflurone diisocyanate are mixed and a first reaction is carried out.

[0011] A second reaction occurs when a solution of a chain extender containing disulfide bonds is added dropwise to the product of the first reaction.

[0012] A silane coupling agent is added to the product of the second reaction to carry out a third reaction, yielding a polyurethane prepolymer;

[0013] (2) The second organic solvent, the first silicon source, water and acid catalyst are mixed to obtain a silica sol presol;

[0014] (3) The polyurethane prepolymer obtained in step (1) is mixed with the silica sol presol obtained in step (2) and then a fourth reaction is carried out. The reaction product is post-treated to obtain a hybrid self-healing polyurethane-silica composite resin.

[0015] (4) The third organic solvent, the second silicon source, the second catalyst and the perfluorosilane are subjected to a fifth reaction to obtain fluorinated superhydrophobic silica sol;

[0016] (5) The hybrid self-healing polyurethane-silica composite resin obtained in step (3) is mixed with the fluorinated superhydrophobic silica sol obtained in step (4) and the fourth organic solvent to obtain the self-healing functional permeation liquid.

[0017] The second aspect of the present invention provides a self-healing permeability-enhancing liquid prepared by the preparation method described in the first aspect.

[0018] The third aspect of the present invention provides an organic-inorganic hybrid coating prepared from the self-healing antireflective liquid described in the second aspect.

[0019] The fourth aspect of the present invention provides the application of the organic-inorganic hybrid coating according to the third aspect as a photovoltaic glass coating.

[0020] The beneficial technical effects achieved by the present invention through the above technical solution are as follows:

[0021] The organic-inorganic hybrid coating obtained by further preparing the self-healing antireflective liquid prepared by this invention has the following advantages:

[0022] (1) It has self-healing function and significantly improves coating durability: By introducing polyurethane-silica composite resin with disulfide bond structure, this invention realizes the automatic repair function of coating when it is damaged by minor scratches or cracks; under the action of heat and ultraviolet light, it exhibits good self-healing behavior through dynamic disulfide bond exchange reaction and can repeatedly repair the cracks in the coating, thereby effectively extending the service life of the coating and reducing the maintenance frequency and cost.

[0023] (2) High transmittance, improving photovoltaic conversion efficiency: The in-situ hybridization strategy is adopted to make SiO2 particles uniformly generated and stably dispersed in the polyurethane matrix, forming a dense and synergistically enhanced composite network structure (enhancing the hardness and wear resistance of the coating, improving the weather resistance of the coating, delaying aging and performance degradation). The average transmittance of the coating in the visible light band can reach more than 96%, maintaining excellent optical performance while possessing functionality, which helps to improve the power generation efficiency of photovoltaic modules.

[0024] (3) Excellent self-cleaning properties and strong anti-pollution ability: This invention can achieve superhydrophobic effect by adjusting the hydrophobicity of the coating surface, and has the ability to wash away dust by rain or water droplets rolling off, effectively preventing the adhesion of dust, oil and other pollutants, and reducing the need for manual cleaning.

[0025] (4) Simple preparation process: The coating preparation method of the present invention has mild process conditions, does not require high temperature and high pressure, and is suitable for a variety of conventional construction methods (such as spraying, dip coating, spin coating, etc.). Detailed Implementation

[0026] The endpoints and any values ​​of the ranges disclosed herein are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0027] The existing technology has the following problems:

[0028] (1) The coating is easily worn and has a short service life: In practical applications, the surface of photovoltaic glass needs to be exposed to the outdoor environment for a long time and is frequently subjected to physical or chemical stresses such as wind and sand, rain, bird droppings, and manual cleaning. Once the surface of the traditional coating is scratched or defective, its functionality (such as self-cleaning and light transmission) will decline rapidly and it will be difficult to maintain for a long time.

[0029] (2) Lack of effective self-repair mechanism: Once the existing coating is damaged at a micro level, it needs to be cleaned or recoated for repair. The process is complicated and costly. Especially on large-area photovoltaic modules, maintenance is difficult and there is a lack of active "self-recovery" capability.

[0030] (3) It is difficult to balance light transmittance and functionality: Some materials that enhance wear resistance or self-healing properties (such as resins or waxes) often sacrifice the optical transmittance of the coating, affecting the power generation efficiency of photovoltaic cells, making it difficult to balance "high light transmittance + functionality".

[0031] The first aspect of this invention provides a method for preparing a self-healing, permeability-enhancing liquid, wherein the method includes the following steps:

[0032] (1) In the presence of a first organic solvent and a first catalyst, polytetrahydrofuran ether diol and isoflurone diisocyanate are mixed and a first reaction is carried out.

[0033] A second reaction occurs when a solution of a chain extender containing disulfide bonds is added dropwise to the product of the first reaction.

[0034] A silane coupling agent is added to the product of the second reaction to carry out a third reaction, yielding a polyurethane prepolymer;

[0035] (2) The second organic solvent, the first silicon source, water and acid catalyst are mixed to obtain a silica sol presol;

[0036] (3) The polyurethane prepolymer obtained in step (1) is mixed with the silica sol presol obtained in step (2) and then a fourth reaction is carried out. The reaction product is post-treated to obtain a hybrid self-healing polyurethane-silica composite resin.

[0037] (4) The third organic solvent, the second silicon source, the second catalyst and the perfluorosilane are subjected to a fifth reaction to obtain fluorinated superhydrophobic silica sol;

[0038] (5) The hybrid self-healing polyurethane-silica composite resin obtained in step (3) is mixed with the fluorinated superhydrophobic silica sol obtained in step (4) and the fourth organic solvent to obtain the self-healing functional permeation liquid.

[0039] The key points of this invention are as follows:

[0040] (1) Introduction of self-healing polyurethane: Polyurethane is prepared by using a chain extender containing bis(2-hydroxyethyl) disulfide. Its thermal reversible properties are utilized to achieve controllable self-healing function under micro-damage conditions, which significantly extends the life of the coating (with reversible disulfide bonds).

[0041] (2) Construction of inorganic / organic hybrid structure: The synthesis reaction of silica sol (sol-gel) is embedded into the synthesis reaction system of polyurethane resin. Blending, polymerization and dispersion are completed in one reaction system to construct a flexible-rigid synergistic network structure, while taking into account the mechanical strength, adhesion and flexibility of the coating.

[0042] (3) Low surface energy modification of fluorinated SiO2: Introducing perfluorosilane-modified superhydrophobic nano-SiO2 to form a rough structure and low-energy interface on the surface, giving the coating excellent self-cleaning and anti-fouling properties without affecting transparency.

[0043] (4) Integrated composite coating design: The two components are uniformly proportioned through sol-gel and physical mixing to form a stable dispersion, achieving comprehensive performance of high light transmittance, self-cleaning, wear resistance, self-repair and room temperature film formation.

[0044] Furthermore, this invention introduces KH550 as an organic-inorganic bridging agent into the polyurethane chain segments, covalently grafting one end of it onto the polyurethane chain and covalently bonding the other end to the SiO2 network formed by in-situ hydrolysis of TEOS, achieving true fusion of organic and inorganic phases rather than physical mixing. A sol-gel system (TEOS + H2O + EtOH + HCl) is introduced in-situ during the later stages of a two-step synthesis and reacts directly with the polyurethane prepolymer, achieving in-situ generation and network connection of SiO2 under mild conditions. This forms a polyurethane composite material with a continuous nanoskeleton, avoiding inorganic particle agglomeration and improving the system's mechanical strength and thermal stability. A hybrid network structure with multiple cross-linking mechanisms is constructed, ensuring material strength while also considering flexibility, self-healing properties, and chemical stability. Additionally, without the synergistic effect of the in-situ SiO2 skeleton and KH550, sufficient contact between the two sides of the crack is difficult to maintain, limiting chain segment migration and reversible disulfide bond exchange, leading to a significant decrease in self-healing efficiency. Therefore, relying solely on HEDS cannot guarantee good self-healing performance of the system; it must be combined with inorganic-organic interpenetrating networks to work synergistically.

[0045] This invention constructs a photovoltaic glass antireflective coating that combines self-healing polyurethane-silica composite resin with fluorinated superhydrophobic silica sol through physical mixing. Structurally, this coating forms a layered synergistic system of an inner flexible self-healing substrate and an outer superhydrophobic functional layer, achieving both efficient damage repair and surface anti-fouling and self-cleaning functions. Optically, through the gradient refractive index design of the inner and outer layers, interface reflection is effectively reduced, significantly improving the coating's transmittance and antireflective effect, exhibiting a clear synergistic advantage. This overcomes the shortcomings of traditional physical mixing systems, such as interface separation and limited performance superposition, demonstrating excellent application value and innovation. In addition, the lack of perfluorosilane will lead to a significant reduction in hydrophobicity (decreased contact angle, easy contamination and failure); slightly affected transmittance (poor refractive index matching, easy particle agglomeration, limited or even slight increase in transmittance); reduced self-healing effect: decreased long-term and cyclic repair capabilities (easy water absorption on the surface, unstable interface, poor chain segment migration); and significantly reduced weather resistance (loss of CF shielding effect, easy moisture absorption, faster aging under UV / heat / water environments).

[0046] This invention achieves a multifunctional composite material system through the synergistic design of polyurethane elastomer segments and in-situ grown nano-silica networks. Compared to traditional physical hybrid materials, this invention not only inherits the flexibility and self-healing ability of polyurethane and the high strength and thermal stability of SiO2, but also achieves a deep fusion of structure and performance through chemical grafting and network intercalation. This significantly improves the material's comprehensive mechanical properties, dimensional stability, self-healing efficiency, and environmental durability, demonstrating a clear synergistic effect. The technical effect is far superior to the simple superposition of functional units.

[0047] In some embodiments of the present invention, in step (1), the first organic solvent is anhydrous tetrahydrofuran. In the present invention, the organic solvent is also used for the solution of bis(2-hydroxyethyl) disulfide (HEDS).

[0048] In some embodiments of the present invention, the first catalyst is selected from at least one of dibutyltin dilaurate (DBTDL) and bismuth neodecanoate (BiND).

[0049] In some embodiments of the present invention, the chain extender containing disulfide bonds is selected from at least one of bis(2-hydroxyethyl) disulfide and bis(3-hydroxypropyl) disulfide.

[0050] In some embodiments of the present invention, the silane coupling agent is selected from at least one of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane.

[0051] In this invention, step (1) is carried out in a protective atmosphere, preferably a nitrogen atmosphere.

[0052] In some embodiments of the present invention, in step (2), the second organic solvent is selected from at least one of anhydrous ethanol, isopropanol and methanol.

[0053] In some embodiments of the present invention, the first silicon source is selected from at least one of tetraethyl orthosilicate, methyl orthosilicate, methyltriethoxysilane, and trimethylethoxysilane.

[0054] In some embodiments of the present invention, the acid catalyst is hydrochloric acid. The concentration of hydrochloric acid is preferably 1 mol / L.

[0055] In some embodiments of the present invention, the hybrid self-healing polyurethane-silica composite resin comprises the following raw materials in weight percentages: polytetrahydrofuran ether diol 17-18.4%, first organic solvent 35.6-36.09%, isoflurone diisocyanate 5.6%, dibutyltin dilaurate 0.01%, bis(2-hydroxyethyl) disulfide 1.5-2.5%, γ-aminopropyltriethoxysilane 1.8-2.3%, second organic solvent 20.5-22%, tetraethyl orthosilicate 11.5%, water 2.9%, and acid catalyst 1.1%.

[0056] In some embodiments of the present invention, the hybrid self-healing polyurethane-silica composite resin comprises the following raw materials in weight percentages: 17.9% polytetrahydrofuran ether diol, 35.79% first organic solvent, 5.6% isoflurane diisocyanate, 0.01% dibutyltin dilaurate, 1.9% bis(2-hydroxyethyl) disulfide, 1.8% γ-aminopropyltriethoxysilane, 21.5% second organic solvent, 11.5% tetraethyl orthosilicate, 2.9% water, and 1.1% acid catalyst.

[0057] In this invention, 10% organic solvent is used to prepare the solution of bis(2-hydroxyethyl) disulfide.

[0058] In some embodiments of the present invention, in step (1), the temperature of the first reaction is 60-80°C, preferably 75°C.

[0059] In some embodiments of the present invention, the time for the first reaction is 1.5-3 hours, preferably 2-2.5 hours.

[0060] In some embodiments of the present invention, the temperature of the second reaction is 30-50°C, preferably 40-50°C.

[0061] In some embodiments of the present invention, the second reaction takes 1-4 hours, preferably 2-3 hours.

[0062] In some embodiments of the present invention, the temperature of the third reaction is 30-50°C, preferably 40°C.

[0063] In some embodiments of the present invention, the time for the third reaction is 1-3 hours, preferably 1-2 hours.

[0064] In some embodiments of the present invention, in step (3), the temperature of the fourth reaction is 30-50°C, preferably 40°C.

[0065] In some embodiments of the present invention, the fourth reaction takes 1-3 hours, preferably 2 hours.

[0066] In some embodiments of the present invention, the post-processing in step (3) includes: heating the product of the fourth reaction to 60°C and distilling it under reduced pressure at a vacuum of -0.095 MPa for 1 h; then drying the concentrate under vacuum at 40°C for 24 h to obtain a hybrid self-healing polyurethane-silica composite resin.

[0067] In some embodiments of the present invention, the fluorinated superhydrophobic silica sol comprises the following raw materials in weight percentages: 77-79% third organic solvent, 9.8% tetraethyl orthosilicate, 7.5-8.5% ammonia, 2.2-3% methyltriethoxysilane, and 1-1.7% perfluorosilane.

[0068] In some embodiments of the present invention, the fluorinated superhydrophobic silica sol comprises the following raw materials in weight percentages: 78.5% third organic solvent, 9.8% tetraethyl orthosilicate, 7.8% ammonia, 2.9% methyltriethoxysilane, and 1% perfluorosilane.

[0069] In some embodiments of the present invention, in step (4), the third organic solvent is selected from at least one of anhydrous ethanol, isopropanol and methanol.

[0070] In some embodiments of the present invention, the second silicon source is selected from at least one of tetraethyl orthosilicate, methyl orthosilicate, butyl orthosilicate, methyltriethoxysilane, methyltrimethoxysilane, ethyltriethoxysilane, and ethyltrimethoxysilane, preferably a combination of tetraethyl orthosilicate and methyltriethoxysilane.

[0071] In some embodiments of the present invention, the second catalyst is selected from at least one of ammonia, sodium hydroxide, and tetramethylammonium hydroxide.

[0072] In some embodiments of the present invention, the perfluorosilane is selected from at least one of perfluorooctyltriethoxysilane, trifluoropropyltrimethoxysilane, and trifluoropropyltriethoxysilane.

[0073] In some embodiments of the present invention, the temperature of the fifth reaction is 50-70°C, preferably 60°C.

[0074] In some embodiments of the present invention, the time for the fifth reaction is 2-6 hours, preferably 4 hours.

[0075] In some embodiments of the present invention, the third organic solvent, tetraethyl orthosilicate and ammonia are first mixed and stirred for 30 min, then methyltriethoxysilane is added and stirred for 2 h, and finally perfluorosilane is added to carry out the reaction.

[0076] In some embodiments of the present invention, in step (5), the fourth organic solvent is selected from at least one of anhydrous ethanol, isopropanol and methanol.

[0077] In some embodiments of the present invention, the mass percentage of the hybrid self-healing polyurethane-silica composite resin is 4.5-5.5%, the mass percentage of the fluorinated superhydrophobic silica sol is 0.25-1%, and the mass percentage of the fourth organic solvent is 94.25-94.5%.

[0078] In some embodiments of the present invention, the hybrid self-healing polyurethane-silica composite resin accounts for 5% by mass, the fluorinated superhydrophobic silica sol accounts for 0.5% by mass, and the fourth organic solvent accounts for 94.5% by mass.

[0079] According to a particularly preferred embodiment of the present invention, a method for preparing a self-healing, permeability-enhancing liquid is provided, wherein the method comprises the following steps:

[0080] 1. Synthesis of polyurethane-silica composite resin:

[0081] (1) Under nitrogen protection, polytetrahydrofuran ether diol (PTMG, Mn=2000) and anhydrous tetrahydrofuran (THF) were added to a three-necked flask and stirred at 60°C to dissolve.

[0082] (2) Slowly add a mixture of isoflurane diisocyanate (IPDI) and dibutyltin dilaurate (DBTDL), heat to 75°C and react for 2 hours, then cool to 40°C for later use.

[0083] (3) Dissolve the bis(2-hydroxyethyl) disulfide chain extender (HEDS) in anhydrous THF and slowly add it dropwise to the product of step (2). React at 40°C for 3 hours.

[0084] (4) Then slowly add γ-aminopropyltriethoxysilane (KH550), react at 40°C for 1 h to obtain polyurethane prepolymer;

[0085] (5) Pre-solution of silica sol: Anhydrous ethanol, tetraethyl orthosilicate (TEOS), deionized water and hydrochloric acid are mixed and stirred at room temperature for 2 hours to form in-situ SiO2 sol.

[0086] (6) Slowly add the silica sol presol to the polyurethane prepolymer and stir at 40°C for 2 hours;

[0087] (7) Heat to 60°C and distill under reduced pressure at a vacuum of -0.095 MPa for 1 h to remove THF solvent (recovery rate >95%).

[0088] (8) The concentrate was then dried under vacuum at 40°C for 24 hours to obtain a hybrid self-healing polyurethane-silica composite resin.

[0089] 2. Synthesis of fluorinated superhydrophobic silica sol:

[0090] Anhydrous ethanol, tetraethyl orthosilicate, and ammonia were added in sequence and stirred for 30 min. Methyltriethoxysilane was added and stirred at room temperature for 2 h. Finally, perfluorosilane was added, and the mixture was heated to 60 °C and stirred for 4 h to obtain fluorinated superhydrophobic silica sol.

[0091] 3. Preparation of self-healing permeability-enhancing fluid:

[0092] Take polyurethane-silica composite resin, fluorinated superhydrophobic silica sol, and anhydrous ethanol, and stir at room temperature for 15 minutes to obtain a self-healing anti-reflective liquid.

[0093] The second aspect of the present invention provides a self-healing permeability-enhancing liquid prepared by the preparation method described in the first aspect.

[0094] The third aspect of the present invention provides an organic-inorganic hybrid coating prepared from the self-healing antireflective liquid described in the second aspect.

[0095] The preparation method of the organic-inorganic hybrid coating can be described as follows:

[0096] 1) Surface cleaning: Clean the surface of the substrate (e.g., photovoltaic glass) to remove dust, oil, and other impurities. It can be rinsed with deionized water and dried with a lint-free cloth. If there are stubborn stains on the surface, you can first clean it with a small amount of ethanol or mild detergent, and then dry it thoroughly.

[0097] 2) Antireflective coating: Stir the self-healing antireflective liquid thoroughly before use. Coating methods include dip coating, brush coating, or roller coating, ensuring the liquid evenly covers the substrate surface.

[0098] 3) Natural drying: After coating, allow to air dry at room temperature for about 30-60 minutes until the surface solvent evaporates and a uniform, transparent coating is formed. If faster curing is required, it can be slightly heated at 40-50℃, but avoid high temperatures that may cause the coating to bubble or crack.

[0099] The fourth aspect of the present invention provides the application of the organic-inorganic hybrid coating according to the third aspect as a photovoltaic glass coating.

[0100] The present invention will be described in detail below through embodiments.

[0101] Unless otherwise specified in the following examples and comparative examples, all conditions were performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments used, unless otherwise specified, are all commercially available products.

[0102] Example 1

[0103] This example illustrates the preparation of a self-healing permeability-enhancing fluid.

[0104] 1. Synthesis of polyurethane-silica composite resin:

[0105] The allocation of each group is as follows (by mass percentage):

[0106] Material Percentage content (%) Polytetrahydrofuran ether diol (PTMG, Mn=2000) 17.9 Anhydrous tetrahydrofuran (THF) 35.79 Isoflurone diisocyanate (IPDI) 5.6 Dibutyltin dilaurate (DBTDL) 0.01 Bis(2-hydroxyethyl) disulfide (HEDS) 1.9 γ-aminopropyltriethoxysilane (KH550) 1.8 Anhydrous ethanol 21.5 Tetraethyl orthosilicate (TEOS) 11.5 Deionized water 2.9 Hydrochloric acid (1 mol / L) 1.1 total 100

[0107] (1) Under nitrogen protection, PTMG was dissolved in THF at 60°C and then IPDI and DBTDL were added. The temperature was raised to 75°C and reacted for 2 hours. The temperature was lowered to 40°C and HEDS dissolved in the reserved 10% THF was added dropwise and reacted for 3 hours. KH550 was then added and reacted for 1 hour to obtain polyurethane prepolymer.

[0108] (2) Anhydrous ethanol, tetraethyl orthosilicate (TEOS), deionized water and hydrochloric acid were stirred at room temperature for 2 hours to form an in-situ SiO2 sol; it was added to the polyurethane prepolymer and reacted at 40°C for 2 hours.

[0109] (3) The reaction product was heated to 60°C and distilled under reduced pressure at a vacuum of -0.095MPa for 1 hour to remove the THF solvent; finally, the concentrate was dried under vacuum at 40°C for 24 hours to obtain the hybrid self-healing polyurethane-silica composite resin.

[0110] 2. Preparation of fluorinated superhydrophobic silica sol:

[0111] Material Percentage content (%) Anhydrous ethanol 78.5 Tetraethyl orthosilicate (TEOS) 9.8 ammonia 7.8 Methyltriethoxysilane (MTES) 2.9 Perfluorosilane (FAS-17) 1 total 100

[0112] Add the components in sequence and stir. React at 60°C for 4 hours to obtain fluorinated superhydrophobic silica sol.

[0113] 3. Preparation of self-healing anti-reflective fluid:

[0114] Material Percentage content (%) Polyurethane-silica composite resin 5.00 Fluorinated superhydrophobic silica sol 0.50 Anhydrous ethanol 94.50 total 100

[0115] Stir at room temperature for 15 minutes to obtain the final self-healing permeability enhancement solution.

[0116] Example 2

[0117] This example illustrates the preparation of a self-healing permeability-enhancing fluid.

[0118] 1. Synthesis of polyurethane-silica composite resin:

[0119] The allocation of each group is as follows (by mass percentage):

[0120] Material Percentage content (%) Polytetrahydrofuran ether diol (PTMG, Mn=2000) 18.4 Anhydrous tetrahydrofuran (THF) 35.69 Isoflurone diisocyanate (IPDI) 5.6 Dibutyltin dilaurate (DBTDL) 0.01 Bis(2-hydroxyethyl) disulfide (HEDS) 2.5 γ-aminopropyltriethoxysilane (KH550) 1.8 Anhydrous ethanol 20.5 Tetraethyl orthosilicate (TEOS) 11.5 Deionized water 2.9 Hydrochloric acid (1 mol / L) 1.1 total 100

[0121] (1) Under nitrogen protection, PTMG was dissolved in THF at 60°C and then IPDI and DBTDL were added. The temperature was raised to 75°C and reacted for 2.5 h. The temperature was lowered to 40°C and HEDS dissolved in the reserved 10% THF was added dropwise and reacted for 2 h. KH550 was then added and reacted for 1 h to obtain polyurethane prepolymer.

[0122] (2) Anhydrous ethanol, tetraethyl orthosilicate (TEOS), deionized water and hydrochloric acid were stirred at room temperature for 2 hours to form an in-situ SiO2 sol; it was added to the polyurethane prepolymer and reacted at 40°C for 2 hours.

[0123] (3) The reaction product was heated to 60°C and distilled under reduced pressure at -0.095MPa for 1 hour to remove the THF solvent; finally, the concentrate was dried under vacuum at 40°C for 24 hours to obtain the hybrid self-healing polyurethane-silica composite resin.

[0124] 2. Preparation of fluorinated superhydrophobic silica sol:

[0125]

[0126]

[0127] Add the components in sequence and stir. React at 60°C for 4 hours to obtain fluorinated superhydrophobic silica sol.

[0128] 3. Preparation of self-healing anti-reflective fluid:

[0129] Material Percentage content (%) Polyurethane-silica composite resin 4.5 Fluorinated superhydrophobic silica sol 1 Anhydrous ethanol 94.50 total 100

[0130] Stir at room temperature for 15 minutes to obtain the final self-healing permeability enhancement solution.

[0131] Example 3

[0132] This example illustrates the preparation of a self-healing permeability-enhancing fluid.

[0133] 1. Synthesis of polyurethane-silica composite resin:

[0134] The allocation of each group is as follows (by mass percentage):

[0135]

[0136]

[0137] (1) Under nitrogen protection, PTMG was dissolved in THF at 60°C and then IPDI and DBTDL were added. The temperature was raised to 75°C and reacted for 2 hours. The temperature was lowered to 50°C and HEDS dissolved in the reserved 10% THF was added dropwise and reacted for 2 hours. KH550 was then added and reacted for 2 hours to obtain polyurethane prepolymer.

[0138] (2) Anhydrous ethanol, tetraethyl orthosilicate (TEOS), deionized water and hydrochloric acid were stirred at room temperature for 2 hours to form an in-situ SiO2 sol; it was added to the polyurethane prepolymer and reacted at 40°C for 2 hours.

[0139] (3) The reaction product was heated to 60°C and distilled under reduced pressure at -0.095MPa for 1 hour to remove the THF solvent; finally, the concentrate was dried under vacuum at 40°C for 24 hours to obtain the hybrid self-healing polyurethane-silica composite resin.

[0140] 2. Preparation of fluorinated superhydrophobic silica sol:

[0141]

[0142]

[0143] Add the components in sequence and stir. React at 60°C for 4 hours to obtain fluorinated superhydrophobic silica sol.

[0144] 3. Preparation of self-healing anti-reflective fluid:

[0145] Material Percentage content (%) Polyurethane-silica composite resin 5.5 Fluorinated superhydrophobic silica sol 0.25 Anhydrous ethanol 94.25 total 100

[0146] Stir at room temperature for 15 minutes to obtain the final self-healing permeability enhancement solution.

[0147] Comparative Example 1

[0148] 1. Synthesis of polyurethane resin:

[0149] The allocation of each group is as follows (by mass percentage):

[0150] Material Percentage content (%) Polytetrahydrofuran ether diol (PTMG, Mn=2000) 28.4 Anhydrous tetrahydrofuran (THF) 56.79 Isoflurone diisocyanate (IPDI) 8.9 Dibutyltin dilaurate (DBTDL) 0.01 Bis(2-hydroxyethyl) disulfide (HEDS) 3 γ-aminopropyltriethoxysilane (KH550) 2.9 total 100

[0151] (1) Under nitrogen protection, PTMG was dissolved in THF at 60°C and then IPDI and DBTDL were added. The temperature was raised to 75°C and reacted for 2 hours. The temperature was lowered to 50°C and HEDS dissolved in the reserved 10% THF was added dropwise and reacted for 2 hours. KH550 was then added and reacted for 2 hours to obtain polyurethane prepolymer.

[0152] (2) The polyurethane prepolymer was heated to 60°C and distilled under reduced pressure at a vacuum of -0.095MPa for 1 hour to remove the THF solvent; finally, the concentrate was dried under vacuum at 40°C for 24 hours to obtain the self-healing polyurethane resin.

[0153] 2. Preparation of fluorinated superhydrophobic silica sol:

[0154] Material Percentage content (%) Anhydrous ethanol 78.5 Tetraethyl orthosilicate (TEOS) 9.8 ammonia 7.8 Methyltriethoxysilane (MTES) 2.9 Perfluorosilane (FAS-17) 1 total 100

[0155] Add the components in sequence and stir. React at 60°C for 4 hours to obtain fluorinated superhydrophobic silica sol.

[0156] 3. Preparation of antireflective liquid for self-healing photovoltaic glass:

[0157] Material Percentage content (%) polyurethane resin 5.00 Fluorinated superhydrophobic silica sol 0.50 Anhydrous ethanol 94.50 total 100

[0158] Stir at room temperature for 15 minutes to obtain the final self-healing permeability enhancement solution.

[0159] Comparative Example 2

[0160] 1. Synthesis of polyurethane-silica composite resin:

[0161] The allocation of each group is as follows (by mass percentage):

[0162] Material Percentage content (%) Polytetrahydrofuran ether diol (PTMG, Mn=2000) 18.4 Anhydrous tetrahydrofuran (THF) 35.69 Isoflurone diisocyanate (IPDI) 5.6 Dibutyltin dilaurate (DBTDL) 0.01 Bis(2-hydroxyethyl) disulfide (HEDS) 2.5 γ-aminopropyltriethoxysilane (KH550) 1.8 Anhydrous ethanol 20.5 Tetraethyl orthosilicate (TEOS) 11.5 Deionized water 2.9 Hydrochloric acid (1 mol / L) 1.1 total 100

[0163] (1) Under nitrogen protection, PTMG was dissolved in THF at 60°C and then IPDI and DBTDL were added. The temperature was raised to 75°C and reacted for 2.5 h. The temperature was lowered to 40°C and HEDS dissolved in the reserved 10% THF was added dropwise and reacted for 2 h. KH550 was then added and reacted for 1 h to obtain polyurethane prepolymer.

[0164] (2) Anhydrous ethanol, tetraethyl orthosilicate (TEOS), deionized water and hydrochloric acid were stirred at room temperature for 2 hours to form an in-situ SiO2 sol; it was added to the polyurethane prepolymer and reacted at 40°C for 2 hours.

[0165] (3) The reaction product was heated to 60°C and distilled under reduced pressure at -0.095MPa for 1 hour to remove the THF solvent; finally, the concentrate was dried under vacuum at 40°C for 24 hours to obtain the hybrid self-healing polyurethane-silica composite resin.

[0166] 2. Preparation of hydrophobic silica sol:

[0167]

[0168] Add the components in sequence and stir. React at 60°C for 4 hours to obtain a hydrophobic sol. 3. Preparation of self-healing and anti-reflective solution:

[0169] Material Percentage content (%) Polyurethane-silica composite resin 4.5 Hydrophobic silica sol 1 Anhydrous ethanol 94.50 total 100

[0170] Stir at room temperature for 15 minutes to obtain the final self-healing permeability enhancement solution.

[0171] Comparative Example 3

[0172] 1. Synthesis of polyurethane-silica composite resin:

[0173] The allocation of each group is as follows (by mass percentage):

[0174]

[0175]

[0176] (1) Under nitrogen protection, PTMG was dissolved in THF at 60°C and then IPDI and DBTDL were added. The temperature was raised to 75°C and reacted for 2 hours. The temperature was lowered to 50°C and then KH550 was added and reacted for 2 hours to obtain polyurethane prepolymer.

[0177] (2) Anhydrous ethanol, tetraethyl orthosilicate (TEOS), deionized water and hydrochloric acid were stirred at room temperature for 2 hours to form an in-situ SiO2 sol; it was added to the polyurethane prepolymer and reacted at 40°C for 2 hours.

[0178] (3) The reaction product was heated to 60°C and distilled under vacuum of -0.095MPa for 1 hour to remove the THF solvent; finally, the concentrate was dried under vacuum at 40°C for 24 hours to obtain the hybrid polyurethane-silica composite resin.

[0179] 2. Preparation of fluorinated superhydrophobic silica sol:

[0180] Material Percentage content (%) Anhydrous ethanol 79 Tetraethyl orthosilicate (TEOS) 9.8 ammonia 7.5 Methyltriethoxysilane (MTES) 2.2 Perfluorosilane (FAS-17) 1.5 total 100

[0181] Add the components in sequence and stir. React at 60°C for 4 hours to obtain fluorinated superhydrophobic silica sol.

[0182] 3. Preparation of self-healing anti-reflective fluid:

[0183]

[0184]

[0185] Stir at room temperature for 15 minutes to obtain the final self-healing permeability enhancement solution.

[0186] Test Example 1

[0187] The self-healing antireflective liquids prepared in Examples 1-3 and Comparative Examples 1-3 were coated on the cleaned photovoltaic glass surface. After natural drying, a uniform and transparent coating (thickness of 150nm±10nm) was formed, and test samples were obtained.

[0188] (1) Transmittance test method:

[0189] Transmittance was tested using spectrophotometry (the standard method).

[0190] Principle: The light transmittance of a specific wavelength range (usually 380-1100nm, covering the solar spectrum) is measured using a spectrophotometer.

[0191] step:

[0192] Calibrate the instrument using a standard reference sample (blank glass).

[0193] Place the photovoltaic glass sample (after coating) in the optical path to avoid contamination or scratches.

[0194] Scan the wavelength range and record the transmission spectrum curve.

[0195] Calculate the weighted average transmittance (based on AM1.5 solar spectral weights).

[0196] The calculation is performed according to the photovoltaic transmittance formula in GB / T 30984.1-2015.

[0197]

[0198] In the formula:

[0199] T – Photovoltaic transmittance;

[0200] T(λ) — Spectral transmittance;

[0201] S λ —Relative spectral distribution of solar radiation when atmospheric mass AM = 1.5;

[0202] Δλ — wavelength interval, in nanometers (nm);

[0203] S λ Δλ—the product of the relative spectral distribution of solar radiation and the wavelength interval, see Appendix A;

[0204] λ — wavelength, measured in nanometers (nm).

[0205] (2) Self-healing performance test:

[0206] Micro-scratches (approximately tens of micrometers wide) were created on the coating surface using a standard scratch instrument. The sample was placed on a heating stage and heated to 60°C. The changes in scratch width were observed using an optical microscope at regular intervals (e.g., 0h, 6h, 12h, 24h, 48h). The disappearance of the scratches or a significant narrowing of their width indicated self-healing functionality.

[0207] (3) Superhydrophobic performance test:

[0208] Using a contact angle meter, 5 μL of distilled water was dropped onto the coating surface, and the static contact angle between the water droplet and the surface was measured.

[0209] (4) Weather resistance test:

[0210] The sample was irradiated under a 320nm ultraviolet lamp for 200 hours, and the transmittance of the sample was tested using the same method as the transmittance test described earlier. The less the transmittance decreased, the better the weather resistance.

[0211] (5) Adhesion test method:

[0212] The test was conducted according to the cross-cut test for paints and varnishes in GB / T 9286-2021.

[0213] Grid cutting tool: Multi-blade cutter (blade spacing 1mm). Use the tool to cut 6 parallel lines on the paint film surface, penetrating the coating to the substrate. Rotate 90° and cut another set of 6 parallel lines to form 25 squares (5×5).

[0214] Apply the tape firmly to the grid area and press it down with your fingers to remove air bubbles. After letting it sit for 60±30 seconds, quickly peel the tape off at a 60° angle (within 0.5-1 second). Set the grade from 0-5 according to the surface paint film peeling level (see Table 1 in GB / T 9286-2021). Grade 0 provides the best results.

[0215] (6) Pencil hardness test method:

[0216] Determination of paint film hardness according to GB / T 6739-2022 Paints and Varnishes Pencil Method.

[0217] Pencil Set: Standard drawing pencils with hardness ranging from soft to hard (6B→5B→4B→3B→2B→B→HB→F→H→2H→3H→4H→5H→6H→7H→8H→9H).

[0218] Make sure the pencil lead protrudes about 5-6mm, and use 400-grit sandpaper to smooth the tip (forming a cylindrical flat tip with no burrs on the edges).

[0219] The pencil was placed at a 45° angle to the paint film surface for testing.

[0220] The results are shown in Table 1.

[0221] Table 1

[0222]

[0223] The results in Table 1 show that:

[0224] Example 1: In this example, the PTMG / THF ratio is moderate, the HEDS content is reasonable, KH550 is used for modification, TEOS forms a stable SiO2 skeleton, and fluorinated superhydrophobic SiO2 (FAS-17) is added. The material has high transmittance (94%), excellent self-healing performance, good hydrophobicity (110°), excellent weather resistance, good adhesion (level 2, slightly lower than the ideal value of level 0), moderate hardness (H), and the best overall performance.

[0225] Example 2: This example has a higher HEDS content, slightly more fluorinated SiO2, a slightly higher PTMG / THF ratio, the strongest hydrophobicity (120°) and higher hardness (2H), slightly lower transmittance (90%), good self-healing ability, and average adhesion (Level 1, close to ideal). Overall, it is suitable for high hardness and hydrophobicity requirements, but its optical performance is slightly inferior to that of Example 1.

[0226] Example 3: In this example, KH550 is slightly higher, fluorinated SiO2 is less, HEDS is lower, PTMG is slightly less, hardness is the highest (3H), weather resistance is excellent, but self-healing effect is moderate, adhesion is the best (0 grade, best), and transmittance is 92%. It is suitable for occasions that emphasize rigidity and weather resistance, but functionality is reduced.

[0227] Comparative Example 1: Lacking a SiO2 framework, although the transmittance is close to that of Example 1 (93.7%), it has low hydrophobicity (95°), poor self-healing ability, average weather resistance, and the worst adhesion (level 3), resulting in significantly insufficient overall functionality.

[0228] Comparative Example 2: The SiO2 framework is retained but FAS-17 is not added. The HEDS is moderate, the PTMG / THF ratio is moderate, the transmittance is 91%, the hydrophobicity is poor (75°), the weather resistance is average, the self-healing ability is average, and the adhesion is close to ideal (Grade 1). It is suitable for emphasizing hardness but the surface is easily damaged.

[0229] Comparative Example 3: This example has a larger SiO2 skeleton, but less FAS-17 and no added HEDS. It has high hardness (3H), good weather resistance, 92% transmittance, moderate hydrophobicity (105°), no self-healing function, and the best adhesion (0 grade). It is suitable for applications that prioritize rigidity but do not emphasize functionality.

[0230] The preferred embodiments of the present invention have been described in detail above; however, the present invention is not limited thereto. Within the scope of the inventive concept, various simple modifications can be made to the technical solutions of the present invention, including combinations of various technical features in any other suitable manner. These simple modifications and combinations should also be considered as the content disclosed in the present invention and are all within the protection scope of the present invention.

Claims

1. A method for preparing a self-healing, permeability-enhancing liquid, characterized in that, The method includes the following steps: (1) In the presence of a first organic solvent and a first catalyst, polytetrahydrofuran ether diol and isoflurone diisocyanate are mixed and a first reaction is carried out. A second reaction occurs when a solution of a chain extender containing disulfide bonds is added dropwise to the product of the first reaction. A silane coupling agent is added to the product of the second reaction to carry out a third reaction, yielding a polyurethane prepolymer; (2) The second organic solvent, the first silicon source, water and acid catalyst are mixed to obtain a silica sol presol; (3) The polyurethane prepolymer obtained in step (1) is mixed with the silica sol presol obtained in step (2) and then a fourth reaction is carried out. The reaction product is post-treated to obtain a hybrid self-healing polyurethane-silica composite resin. (4) The third organic solvent, the second silicon source, the second catalyst and the perfluorosilane are subjected to a fifth reaction to obtain fluorinated superhydrophobic silica sol; (5) The hybrid self-healing polyurethane-silica composite resin obtained in step (3) is mixed with the fluorinated superhydrophobic silica sol obtained in step (4) and the fourth organic solvent to obtain the self-healing functional permeation liquid.

2. The preparation method according to claim 1, wherein, In step (1), the first organic solvent is anhydrous tetrahydrofuran; Preferably, the first catalyst is selected from at least one of dibutyltin dilaurate and bismuth neodecanoate; Preferably, the chain extender containing disulfide bonds is selected from at least one of bis(2-hydroxyethyl) disulfide and bis(3-hydroxypropyl) disulfide; Preferably, the silane coupling agent is selected from at least one of γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and N-(2-aminoethyl)-3-aminopropyltrimethoxysilane. Preferably, in step (2), the second organic solvent is selected from at least one of anhydrous ethanol, isopropanol, and methanol; Preferably, the first silicon source is selected from at least one of tetraethyl orthosilicate, methyl orthosilicate, methyltriethoxysilane, and trimethylethoxysilane; Preferably, the acid catalyst is hydrochloric acid; the concentration of the hydrochloric acid is preferably 1 mol / L. Preferably, the hybrid self-healing polyurethane-silica composite resin comprises the following raw materials in weight percentage: polytetrahydrofuran ether diol 17-18.4%, first organic solvent 35.6-36.09%, isoflurone diisocyanate 5.6%, dibutyltin dilaurate 0.01%, bis(2-hydroxyethyl) disulfide 1.5-2.5%, γ-aminopropyltriethoxysilane 1.8-2.3%, second organic solvent 20.5-22%, tetraethyl orthosilicate 11.5%, water 2.9%, and acid catalyst 1.1%. Preferably, the hybrid self-healing polyurethane-silica composite resin comprises the following raw materials in weight percentage: 17.9% polytetrahydrofuran ether diol, 35.79% first organic solvent, 5.6% isoflurane diisocyanate, 0.01% dibutyltin dilaurate, 1.9% bis(2-hydroxyethyl) disulfide, 1.8% γ-aminopropyltriethoxysilane, 21.5% second organic solvent, 11.5% tetraethyl orthosilicate, 2.9% water, and 1.1% acid catalyst.

3. The preparation method according to claim 1 or 2, wherein, In step (1), the temperature of the first reaction is 60-80℃, preferably 75℃; Preferably, the time for the first reaction is 1.5-3 hours, more preferably 2-2.5 hours; Preferably, the temperature of the second reaction is 30-50°C, more preferably 40-50°C; Preferably, the second reaction takes 1-4 hours, more preferably 2-3 hours; Preferably, the temperature of the third reaction is 30-50°C, and more preferably 40°C; Preferably, the third reaction takes 1-3 hours, more preferably 1-2 hours; Preferably, in step (3), the temperature of the fourth reaction is 30-50°C, more preferably 40°C; Preferably, the fourth reaction takes 1-3 hours, more preferably 2 hours.

4. The preparation method according to any one of claims 1-3, wherein, The post-processing in step (3) includes: heating the product of the fourth reaction to 60°C and distilling it under reduced pressure at a vacuum of -0.095 MPa for 1 hour; then drying the concentrate under vacuum at 40°C for 24 hours to obtain a hybrid self-healing polyurethane-silica composite resin.

5. The preparation method according to any one of claims 1-4, wherein, The fluorinated superhydrophobic silica sol comprises the following raw materials in weight percentage: 77-79% of a third organic solvent alcohol, 9.8% of tetraethyl orthosilicate, 7.5-8.5% of ammonia, 2.2-3% of methyltriethoxysilane, and 1-1.7% of perfluorosilane; Preferably, the fluorinated superhydrophobic silica sol comprises the following raw materials in weight percentage: 78.5% third organic solvent, 9.8% tetraethyl orthosilicate, 7.8% ammonia, 2.9% methyltriethoxysilane, and 1% perfluorosilane.

6. The preparation method according to any one of claims 1-5, wherein, In step (4), the third organic solvent is selected from at least one of anhydrous ethanol, isopropanol, and methanol; Preferably, the second silicon source is selected from at least one of tetraethyl orthosilicate, methyl orthosilicate, butyl orthosilicate, methyltriethoxysilane, methyltrimethoxysilane, ethyltriethoxysilane, and ethyltrimethoxysilane, and more preferably a combination of tetraethyl orthosilicate and methyltriethoxysilane; Preferably, the second catalyst is selected from at least one of ammonia, sodium hydroxide, and tetramethylammonium hydroxide; Preferably, the perfluorosilane is selected from at least one of perfluorooctyltriethoxysilane, trifluoropropyltrimethoxysilane, and trifluoropropyltriethoxysilane; Preferably, the temperature of the fifth reaction is 50-70°C, and more preferably 60°C; Preferably, the fifth reaction takes 2-6 hours, more preferably 4 hours; Preferably, the third organic solvent, tetraethyl orthosilicate and ammonia are first mixed and stirred for 30 min, then methyltriethoxysilane is added and stirred for 2 h, and finally perfluorosilane is added to carry out the reaction.

7. The preparation method according to any one of claims 1-6, wherein, In step (5), the fourth organic solvent is selected from at least one of anhydrous ethanol, isopropanol, and methanol; Preferably, the mass percentage of the hybrid self-healing polyurethane-silica composite resin is 4.5-5.5%, the mass percentage of the fluorinated superhydrophobic silica sol is 0.25-1%, and the mass percentage of the fourth organic solvent is 94.25-94.5%. Preferably, the hybrid self-healing polyurethane-silica composite resin comprises 5% by mass, the fluorinated superhydrophobic silica sol comprises 0.5% by mass, and the fourth organic solvent comprises 94.5% by mass.

8. A self-healing permeability-enhancing liquid prepared by any one of claims 1-7.

9. An organic-inorganic hybrid coating prepared from the self-healing antireflective liquid of claim 8.

10. The application of the organic-inorganic hybrid coating according to claim 9 as a photovoltaic glass coating.

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