Strontium titanate nanomaterial, preparation method therefor and use thereof

Abstract

A strontium titanate nanomaterial, a preparation method therefor and a use thereof. The raw materials for preparing the strontium titanate nanomaterial comprise a base material and a dispersant; the mass of the dispersant is 0.05-0.2% of the mass of the base material; in terms of mass fraction, the raw materials for preparing the base material comprise 50-90 parts of a powdered resin, 10-50 parts of a curing agent, 0-20 parts of an antioxidant, 0.05-0.2 parts of a catalyst, 0-10 parts of a surface conditioner, 0-20 parts of a light stabilizer, and 0.05-5 parts of a strontium titanate nano-additive, the strontium titanate nano-additive being a mixture of octadecahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate in a mass ratio of 3-4:4-6:1-2; the strontium titanate nanomaterial has excellent weathering resistance.

Description

A strontium titanate nanomaterial and its preparation method and application

[0001] This application claims priority to the Chinese patent application filed with the Patent Office of China on June 29, 2023, with application number CN202310776712.1 and invention name “A strontium titanate nanomaterial, its preparation method and application”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of functional materials, and in particular to a strontium titanate nanomaterial and a preparation method and application thereof. Background Art

[0003] Solar energy is a clean energy source. Solar photovoltaic power generation relies on solar cells to convert sunlight directly into electricity. Individual solar cells cannot be used directly as a power source; instead, they must be connected in series and parallel and tightly packaged into photovoltaic modules. Photovoltaic modules, also known as solar panels, are the core component of solar power generation systems. They operate based on the photovoltaic effect, converting solar energy into electricity.

[0004] Traditional photovoltaic applications are primarily centralized, primarily for ground-based applications. With the continuous advancement of photovoltaic technology and the expansion of its application scenarios, the proportion of distributed photovoltaic power generation is rapidly increasing. Distributed photovoltaic power generation refers to photovoltaic power generation facilities built near user sites, operating in a manner characterized by self-generation and self-consumption by users, with excess power being fed into the grid, and balancing regulation within the distribution system. Distributed photovoltaic power generation adheres to the principles of adapting to local conditions, being clean and efficient, decentralized, and utilizing resources locally. It can fully utilize local solar resources, replacing and reducing fossil energy consumption.

[0005] Traditional photovoltaic modules typically use tempered glass as the encapsulation material to encapsulate the cells, which presents challenges such as heavy weight, limited application scenarios, difficult installation, and lack of aesthetic appeal. To address these issues, lightweight photovoltaic modules have emerged to meet the demands of the distributed photovoltaic market. These encapsulation materials are typically based on acrylic powder coatings, which primarily consist of acrylic resin, a curing agent, and some conventional additives, but suffer from insufficient weather resistance.

[0006] Summary of the Invention

[0007] The purpose of the present invention is to provide a strontium titanate nanomaterial and a preparation method and application thereof. The strontium titanate nanomaterial provided by the present invention has excellent weather resistance.

[0008] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0009] The present invention provides a strontium titanate nanomaterial, the preparation raw materials include a base material and a dispersant, the mass of the dispersant is 0.05-0.2% of the mass of the base material;

[0010] The matrix material comprises the following raw materials by weight: 50-90 parts of powdered resin; 10-50 parts of curing agent; 0-20 parts of antioxidant; 0.05-0.2 parts of catalyst; 0-10 parts of surface conditioner; 0-20 parts of light stabilizer;

[0011] 0.05 to 5 parts of strontium titanate nano-additive, which is a mixture of octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate, and the mass ratio of the octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate is 3 to 4:4 to 6:1 to 2.

[0012] Preferably, the particle size of the strontium titanate nano-additive is 50 to 300 nm.

[0013] Preferably, the particle size of the octahedral strontium titanate is 100 to 200 nm; the particle size of the hexahedral strontium titanate is 100 to 200 nm; and the particle size of the irregular strontium titanate is 50 to 100 nm.

[0014] Preferably, the powder resin includes one or more of acrylic resin, polyurethane resin and polyester resin.

[0015] Preferably, the acrylic resin is an epoxy acrylic resin.

[0016] Preferably, the curing agent includes one or more of dodecanedicarboxylic acid, triglycidyl isocyanurate and isocyanate.

[0017] Preferably, the antioxidant auxiliary agent includes one or more of β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, benzofuranone derivatives and thioester antioxidants.

[0018] Preferably, the catalyst comprises tetrabutylammonium bromide, dibutyltin dilaurate or 2-propylimidazole.

[0019] Preferably, the surface conditioning agent comprises benzoin.

[0020] Preferably, the light stabilizer includes a triazine light stabilizer or a hindered amine light stabilizer.

[0021] Preferably, the particle size of the matrix material is 30 to 150 μm.

[0022] Preferably, the dispersant includes one or more of alumina, fumed silica and glass microspheres.

[0023] Preferably, the particle size of the dispersant is 2 to 8 μm.

[0024] The present invention provides a method for preparing the strontium titanate nanomaterial described in the above technical solution, comprising the following steps:

[0025] The raw materials for preparing the matrix material are mixed, and the mixture is subjected to melt extrusion, cooling, crushing and screening in sequence to obtain the matrix material; the matrix material is mixed with a dispersant to obtain the strontium titanate nanomaterial;

[0026] Alternatively, the raw materials for preparing the matrix material are mixed with a dispersant, and the mixture is melt-extruded, cooled, crushed and sieved in sequence to obtain the strontium titanate nanomaterial.

[0027] Preferably, the temperature of the melt extrusion is 90-130°C.

[0028] The present invention provides the use of the strontium titanate nanomaterial described in the above technical solution or the strontium titanate nanomaterial prepared by the preparation method described in the above technical solution in photovoltaic module packaging materials.

[0029] Beneficial Effects: The strontium titanate nanomaterial of the present invention comprises a strontium titanate nano-additive added to the base material, and the strontium titanate nano-additive is compounded with strontium titanate of a specific morphology. This imparts excellent weather resistance to the strontium titanate nanomaterial, while also improving its photoelectric conversion efficiency, making it suitable for use as a photovoltaic module packaging material. The results of the examples show that the strontium titanate nanomaterial provided by the present invention exhibits excellent resistance to ultraviolet aging, neutral salt spray, and moisture-heat, as well as high photoelectric conversion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] FIG1 is a SEM image of hexahedral strontium titanate;

[0031] FIG2 is a SEM image of a mixture of irregular strontium titanate and octahedral strontium titanate;

[0032] FIG3 is a diagram showing the moisture and heat resistance test of the material prepared in Example 1;

[0033] FIG4 is a diagram showing the moisture and heat resistance test of the material prepared in Comparative Example 1;

[0034] FIG5 is a graph showing the UV aging test of the material prepared in Example 1 in Test Example 3;

[0035] FIG6 is a graph showing the UV aging test of the material prepared in Comparative Example 1 in Test Example 3;

[0036] FIG7 is a graph showing UV aging test results of the materials prepared in Example 1, Comparative Example 2, and Comparative Example 3 in Test Example 4;

[0037] FIG8 is a graph showing the UV aging test of the materials prepared in Comparative Examples 4, 5, and 6 in Test Example 4;

[0038] FIG9 is a graph showing the UV aging test of the materials prepared in Comparative Examples 7, 8 and 9 in Test Example 4;

[0039] FIG10 is a graph showing neutral salt spray test results of the materials prepared in Example 1, Comparative Example 2, and Comparative Example 3;

[0040] FIG11 is a neutral salt spray test diagram of the materials prepared in Comparative Examples 4, 5, and 6;

[0041] FIG12 is a neutral salt spray test diagram of the materials prepared in Comparative Examples 7, 8, and 9. DETAILED DESCRIPTION

[0042] The present invention provides a strontium titanate nanomaterial, the preparation raw materials include a base material and a dispersant, the mass of the dispersant is 0.05-0.2% of the mass of the base material;

[0043] The matrix material comprises the following raw materials by weight: 50-90 parts of powdered resin; 10-50 parts of curing agent; 0-20 parts of antioxidant; 0.05-0.2 parts of catalyst; 0-10 parts of surface conditioner; 0-20 parts of light stabilizer;

[0044] 0.05 to 5 parts of strontium titanate nano-additive, which is a mixture of octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate, and the mass ratio of the octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate is 3 to 4:4 to 6:1 to 2.

[0045] The strontium titanate nanomaterial described in the present invention is a powder coating used for photovoltaic module packaging materials and has excellent weather resistance; the nanomaterial described in the present invention is based on material size, namely nanoscale materials and microscale materials, and is not based on the amount of strontium titanate nano-additive used.

[0046] In the present invention, unless otherwise specified, the raw materials used are commercially available products well known to those skilled in the art or are prepared using methods well known to those skilled in the art.

[0047] In the present invention, the raw materials for preparing the strontium titanate nanomaterials include a matrix material; in parts by mass, the raw materials for preparing the matrix material include 50 to 90 parts of powdered resin, preferably 55 to 80 parts, more preferably 60 to 78 parts, further preferably 65 to 75 parts, and even more preferably 70 to 72 parts. In the present invention, the powdered resin preferably includes one or more of acrylic resin, polyurethane resin and polyester resin, more preferably acrylic resin. The present invention preferably uses acrylic resin as the main material, which has the advantages of good weather resistance, high film-forming strength, excellent impact resistance and excellent flexibility. In the present invention, the acrylic resin is preferably an epoxy acrylic resin, more preferably the epoxy acrylic powder coating resin described in patent CN115651473A; specifically, the raw materials of the epoxy acrylic powder coating resin include 20 to 70 parts of a hard monomer, 10 to 60 parts of a soft monomer, 10 to 50 parts of a cross-linking monomer and 0.5 to 8 parts of an initiator; the cross-linking monomer includes an epoxy-containing monomer and / or a hydroxyl-containing monomer; the hard monomer includes at least one of methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobornyl methacrylate, dicyclopentadiene acrylate, dicyclopentadiene ethoxyacrylate, styrene, methyl styrene or acrylonitrile; the soft monomer includes an alkyl acrylate compound; the epoxy-containing monomer includes glycidyl methacrylate, glycidyl acrylate, hydroxybutyl glycidyl acrylate, or the like. or at least one of versatile carbonic acid glycidyl ether; the hydroxyl-containing monomer includes at least one of hydroxyethyl acrylate, hydroxyethyl methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, β-hydroxypropyl acrylate, β-hydroxypropyl methacrylate or N-hydroxymethyl acrylamide; the mass ratio of the epoxy-containing monomer to the hydroxyl-containing monomer in the cross-linking monomer is (2-15):1; the epoxy type acrylic powder coating resin is prepared by the following method, which comprises: dropwise adding a mixture of a hard monomer, a soft monomer, a cross-linking monomer, 40-50% of an initiator in a formula amount and an optional molecular weight regulator into a solvent, after a first reaction, dropwise adding the remaining initiator, and continuing the reaction to obtain the epoxy type acrylic powder coating resin; the temperature of the first reaction is 80-110° C., the time is 2-4 hours, and the time of the continued reaction is 2-4.5 hours.

[0048] Based on the mass fraction of the powdered resin, the raw materials for preparing the matrix material of the present invention include 10 to 50 parts of a curing agent, preferably 15 to 30 parts, more preferably 18 to 25 parts, and even more preferably 20 to 21 parts. In the present invention, the curing agent preferably includes one or more of dodecanoic acid (DDDA), triglycidyl isocyanurate (TGIC), and isocyanate, more preferably DDDA, TGIC, or isocyanate. The present invention preferably uses the above-mentioned types of curing agents, which are beneficial to improving film-forming efficiency while ensuring the basic physical properties of the film.

[0049] Based on the mass fraction of the powdered resin, the raw materials for preparing the matrix material of the present invention include 0 to 20 parts of an antioxidant, preferably 0.3 to 10 parts, more preferably 0.5 to 5 parts, and even more preferably 1 to 2 parts. In the present invention, the antioxidant preferably includes one or more of β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (Antioxidant 1076), benzofuranone derivatives, and thioesters, more preferably Antioxidant 1076. The present invention preferably uses the above-mentioned antioxidants to improve weather resistance.

[0050] Based on the mass fraction of the powdered resin, the raw materials for preparing the matrix material of the present invention include 0.05 to 0.2 parts of catalyst, preferably 0.06 to 0.15 parts, more preferably 0.07 to 0.1 parts, and even more preferably 0.075 to 0.085 parts. In the present invention, the catalyst preferably includes tetrabutylammonium bromide, dibutyltin dilaurate, or 2-propylimidazole, and more preferably tetrabutylammonium bromide. The present invention preferably uses the above-mentioned catalysts to improve film formation efficiency.

[0051] The raw materials used to prepare the matrix material of the present invention include 0 to 10 parts by weight of the powdered resin, preferably 0.3 to 5 parts, more preferably 0.5 to 2 parts, and even more preferably 0.8 to 1 part of a surface conditioner. In the present invention, the surface conditioner preferably includes benzoin. The preferred use of the above-mentioned surface conditioners in the present invention facilitates improved surface smoothness and light transmittance after film formation.

[0052] Based on the mass fraction of the powdered resin, the raw materials for preparing the matrix material of the present invention include 0 to 20 parts of a light stabilizer, preferably 0.5 to 15 parts, more preferably 0.8 to 10 parts, further preferably 1.2 to 7 parts, and even more preferably 1.66 to 3 parts. In the present invention, the light stabilizer preferably includes a triazine light stabilizer or a hindered amine light stabilizer, more preferably a triazine light stabilizer; the triazine light stabilizer is preferably 2-[2-hydroxy-4-[3-(2-ethylhexyloxy)-2-hydroxypropoxy]phenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine (light stabilizer UV-405); the hindered amine light stabilizer is preferably one or more of high molecular weight triazine-piperidine condensate (light stabilizer 119), Tinuvin 622, and Tinuvin 770. The present invention preferably uses the above-mentioned light stabilizers to improve weather resistance.

[0053] Based on the mass fraction of the powdered resin, the raw materials for preparing the matrix material in the present invention include 0.05 to 5 parts of strontium titanate nano-additive, preferably 0.1 to 4.8 parts, more preferably 0.5 to 4.5 parts, further preferably 1 to 4 parts, further preferably 1.5 to 3.5 parts, and even more preferably 2 to 3.45 parts. In the present invention, the strontium titanate nano-additive is a mixture of octahedral strontium titanate, hexahedral strontium titanate, and irregular strontium titanate, and the mass ratio of the octahedral strontium titanate, hexahedral strontium titanate, and irregular strontium titanate is 3 to 4:4 to 6:1 to 2, preferably 3 to 3.5:5 to 6:1 to 1.5, and more preferably 3:6:1. In the present invention, the particle size of the strontium titanate nano-additive is preferably 50 to 300 nm, more preferably 50 to 200 nm; in the present invention, the particle size of the octahedral strontium titanate is preferably 100 to 200 nm, the particle size (side length) of the hexahedral strontium titanate is preferably 100 to 200 nm, and the particle size of the irregular strontium titanate is preferably 50 to 100 nm. In the present invention, the strontium titanate nano-additive is obtained by compounding strontium titanate of a specific morphology, which can make the strontium titanate nano-material have excellent weather resistance; and the compounding of strontium titanate of different morphologies can provide different crystal planes, which is conducive to the efficient separation of photoinduced charges and holes, thereby improving the photoelectric conversion efficiency.

[0054] In the present invention, the raw materials for preparing the strontium titanate nanomaterial include a dispersant, which preferably includes one or more of alumina, fumed silica, and glass beads, with alumina being more preferred. In the present invention, the mass of the dispersant is 0.05-0.2% of the mass of the matrix material, preferably 0.1-0.15%. The preferred use of the above-mentioned dispersants helps prevent agglomeration and improves product processing performance.

[0055] In the present invention, the particle size of the matrix material is preferably 30 to 150 μm; the particle size of the dispersant is preferably 2 to 8 μm, more preferably 2 to 4 μm.

[0056] The present invention provides a method for preparing the strontium titanate nanomaterial described in the above technical solution, comprising the following steps:

[0057] The raw materials for preparing the matrix material are mixed, and the mixture is subjected to melt extrusion, cooling, crushing and screening in sequence to obtain the matrix material; the matrix material is mixed with a dispersant to obtain the strontium titanate nanomaterial;

[0058] Alternatively, the raw materials for preparing the matrix material are mixed with a dispersant, and the mixture is melt-extruded, cooled, crushed and sieved in sequence to obtain the strontium titanate nanomaterial.

[0059] In the present invention, different methods can be used to prepare the strontium titanate nanomaterials according to the timing of adding the dispersant, which will be described in detail below.

[0060] Method 1: The raw materials for preparing the matrix material are mixed and sequentially subjected to melt extrusion, cooling, pulverization, and screening to obtain the matrix material. The matrix material is then mixed with a dispersant to obtain the strontium titanate nanomaterial. In the present invention, the raw materials for preparing the matrix material are preferably mixed mechanically. The conditions for mechanical mixing are not particularly limited, as long as the raw materials are uniformly mixed. In the present invention, the temperature for melt extrusion is preferably 90-130°C, more preferably 110-120°C. The cooling method is not particularly limited, and any cooling method known to those skilled in the art can be employed. In the present invention, the pulverization preferably includes a first pulverization and a second pulverization. The first pulverization preferably pulverizes the material to a particle size of 0.2-1 cm, and the second pulverization preferably pulverizes the material to a particle size of 30-150 μm. The screening method is not particularly limited, as long as a matrix material of the desired particle size is obtained. In the present invention, the raw materials for preparing the matrix material are preferably mixed mechanically. The conditions for mechanical mixing are not particularly limited, as long as the matrix material and dispersant are uniformly mixed.

[0061] The second method: The present invention mixes the raw materials for preparing the matrix material with a dispersant, and sequentially melt-extrudes, cools, crushes and screens to obtain the strontium titanate nanomaterial. In the present invention, the raw materials for preparing the matrix material and the dispersant are preferably mixed mechanically. The present invention does not specifically limit the conditions for the mechanical mixing, as long as the raw materials are uniformly mixed. In the present invention, the specific operations of melt extrusion, cooling, crushing and screening involved in the second method are preferably consistent with the specific operations of melt extrusion, cooling, crushing and screening involved in the first method, and will not be repeated here.

[0062] The present invention provides the use of the strontium titanate nanomaterial described in the above technical solution or the strontium titanate nanomaterial prepared by the preparation method described in the above technical solution in the packaging material of a photovoltaic module. In the present invention, the photovoltaic module is preferably a lightweight photovoltaic module, and the packaging material is specifically a composite flexible material (Compound Flexible Material, CFM) prepared by using strontium titanate nanomaterial and fiber cloth. The composite flexible material prepared using the strontium titanate nanomaterial provided by the present invention has good weather resistance, excellent ductility (elongation at break ≥16%) and mechanical strength (tensile strength ≥150MPa), and high light transmittance (≥90%); and the surface of the composite flexible material has the characteristics of high anti-fouling and easy cleaning, and the main dirt can usually be removed by washing with rainwater.

[0063] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions of the present invention. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. 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.

[0064] The strontium titanate nano-additives used in the examples and comparative examples of the present invention are the products prepared in Preparation Examples 1 to 3.

[0065] Preparation Example 1

[0066] The steps for preparing hexahedral strontium titanate nanoparticles are as follows:

[0067] Palmitic acid, ethylene glycol, 1,2-butanediol, and water are mixed to obtain a composite morphology regulator, wherein the concentration of palmitic acid, the concentration of ethylene glycol, and the concentration of 1,2-butanediol are 0.2 wt %, and the concentration of 1,2-butanediol are 2 wt %; a titanium tetrachloride aqueous solution having a concentration of 0.003 g / mL is added dropwise to the composite morphology regulator, and the volume ratio of the composite morphology regulator to the titanium tetrachloride aqueous solution is 1:2, and the mixture is stirred for 30 minutes. During the stirring process, the mixture is cooled with ice water to obtain a mixed solution I;

[0068] The mixed solution I, a lithium hydroxide aqueous solution with a concentration of 0.033 g / mL, and a strontium hydroxide aqueous solution with a concentration of 0.01 g / mL were mixed in a volume ratio of 3:3:1, and stirred for 15 minutes to obtain a mixed solution II with a pH value of 13.8;

[0069] The mixed solution II was heated to 180°C at a heating rate of 4°C / min for a hydrothermal reaction for 48 hours, and then cooled at a cooling rate of 2°C / min. The material after the hydrothermal reaction was centrifuged, and the precipitate was washed alternately with water and ethanol 5 times, and finally dried at 90°C for 4 hours to obtain hexahedral strontium titanate nanoparticles.

[0070] Preparation Example 2

[0071] The steps for preparing octahedral strontium titanate nanoparticles are as follows:

[0072] Palmitic acid, ethylene glycol, 1,2-butanediol, and water are mixed to obtain a composite morphology regulator, wherein the concentration of palmitic acid in the composite morphology regulator is 0.2 wt %, the concentration of ethylene glycol is 1 wt %, and the concentration of 1,2-butanediol is 0.2 wt %; a titanium tetrachloride aqueous solution having a concentration of 0.003 g / mL is added dropwise to the composite morphology regulator, and the volume ratio of the composite morphology regulator to the titanium tetrachloride aqueous solution is 1:2, and the mixture is stirred for 30 minutes. During the stirring process, ice water is used for cooling to obtain a mixed solution I;

[0073] The mixed solution I, a sodium hydroxide aqueous solution with a concentration of 0.033 g / mL, and a strontium chloride hexahydrate aqueous solution with a concentration of 0.01 g / mL were mixed in a volume ratio of 3:3:1, and stirred for 30 minutes to obtain a mixed solution II with a pH value of 14.2;

[0074] The mixed solution II was heated to 190°C at a heating rate of 4°C / min for a hydrothermal reaction for 24 hours, and then cooled at a cooling rate of 2°C / min. The material after the hydrothermal reaction was centrifuged, and the precipitate was washed alternately with water and ethanol three times, and finally dried at 80°C for 6 hours to obtain octahedral strontium titanate nanoparticles.

[0075] Preparation Example 3

[0076] The steps for preparing irregular strontium titanate are as follows:

[0077] Palmitic acid, ethylene glycol, 1,2-butanediol, and water were mixed to obtain a composite morphology regulator, wherein the concentration of palmitic acid in the composite morphology regulator was 0.2 wt %, the concentration of ethylene glycol was 1.2 wt %, and the concentration of 1,2-butanediol was 1.6 wt %; a titanium tetrachloride aqueous solution with a concentration of 0.003 g / mL was added dropwise to the composite morphology regulator, and the volume ratio of the composite morphology regulator to the titanium tetrachloride aqueous solution was 1:2, and the mixture was stirred for 30 minutes. During the stirring process, ice water was used for cooling to obtain a mixed solution I;

[0078] The mixed solution I, a sodium hydroxide aqueous solution with a concentration of 0.033 g / mL, and a strontium chloride hexahydrate aqueous solution with a concentration of 0.01 g / mL were mixed in a volume ratio of 3:3:1, and stirred for 30 minutes to obtain a mixed solution II with a pH value of 14.2;

[0079] The mixed solution II was heated to 180°C at a heating rate of 4°C / min for a hydrothermal reaction for 72 hours, and then cooled at a cooling rate of 2°C / min. The material after the hydrothermal reaction was centrifuged, and the precipitate was washed alternately with water and ethanol 5 times, and finally dried at 80°C for 6 hours to obtain irregular strontium titanate nanoparticles.

[0080] FIG1 is a SEM image of hexahedral strontium titanate. As can be seen from FIG1 , the side length of the hexahedral strontium titanate is about 100 to 200 nm.

[0081] FIG2 is a SEM image of a mixture of irregular strontium titanate and octahedral strontium titanate. As shown in FIG2 , the particle size of the irregular strontium titanate is about 50 to 100 nm, and the particle size of the octahedral strontium titanate is about 100 to 200 nm.

[0082] Example 1

[0083] In this embodiment, the raw materials for preparing strontium titanate nanomaterials include a base material and a dispersant;

[0084] 72 parts by mass of an acrylic resin (specifically, the epoxy acrylic powder coating resin prepared in Example 7 of patent CN 115651473A), 21 parts of a curing agent (specifically, DDDA), 1 part of an antioxidant (specifically, antioxidant 1076), 0.085 parts of a catalyst (specifically, tetrabutylammonium bromide), 0.8 parts of a surface conditioner (specifically, benzoin), 1.66 parts of a light stabilizer (specifically, light stabilizer UV-405), and 3.45 parts of a strontium titanate nano-additive (specifically, a mixture of octahedral strontium titanate, hexahedral strontium titanate, and irregular strontium titanate in a mass ratio of 3:6:1) were mixed, melt-extruded at 120° C., and the resulting extrudate was cooled and crushed to a particle size of 0.2 to 1 cm. The extrudate was then further crushed and graded and sieved to obtain a matrix material with a particle size of 30 to 150 μm.

[0085] The dispersant is aluminum oxide, and the particle size of the dispersant is 2 to 4 μm; the mass of the dispersant is 0.1% of the mass of the base material;

[0086] The matrix material is mixed with a dispersant to obtain strontium titanate nanomaterials.

[0087] Comparative Example 1

[0088] Photovoltaic competitor powder sample, specifically the acrylic powder coating of Example 2 in Chinese patent CN201810420474.X.

[0089] Test Example 1

[0090] The materials prepared in the examples and comparative examples were subjected to a neutral salt spray (NSS) test, as follows:

[0091] 1. Test method: ISO 9227:2017.

[0092] 2. Test conditions:

[0093] Sedimentation salt solution concentration: (50+5)g / LNaCl;

[0094] Test chamber temperature: (35±2)℃;

[0095] Salt spray deposition rate: (1.5+0.5)mL / (80cm 2 h);

[0096] pH value of sedimentation salt solution (25±2)℃: 6.5~7.2.

[0097] 3. Test time: 1000h.

[0098] 4. Testing equipment: Programmable salt spray testing machine, model: CZ-120C.

[0099] 5. Test results: As shown in Table 1. As shown in Table 1, the strontium titanate nanomaterial prepared in Example 1 of the present invention and the photovoltaic competitor powder sample in Comparative Example 1 both passed the neutral salt spray test for 1000 h.

[0100] Table 1 Neutral salt spray test results

[0101] Test Example 2

[0102] The materials prepared in the examples and comparative examples were subjected to a moisture and heat resistance test, specifically as follows:

[0103] 1. Test method: Refer to standard IEC60068-2-67.

[0104] 2. Test conditions:

[0105] Test temperature: (85±2)℃;

[0106] Relative humidity: (85±5)%.

[0107] 3. Test time: 1480h.

[0108] 4. Testing equipment: Programmable constant temperature and humidity test chamber, model: ZH-TH-225D.

[0109] 5. Test results: As shown in Table 2 and Figures 3 to 4, Figure 3 is a moisture and heat resistance test diagram of the material prepared in Example 1, and Figure 4 is a moisture and heat resistance test diagram of the material prepared in Comparative Example 1. It can be seen from Table 2 and Figures 3 to 4 that the strontium titanate nanomaterial prepared in Example 1 of the present invention and the photovoltaic competitor powder sample in Comparative Example 1 both passed the moisture and heat resistance test for 1480 hours, meeting customer requirements.

[0110] Table 2 Humidity and heat resistance test results

[0111] Test Example 3

[0112] The materials prepared in the examples and comparative examples were subjected to UV aging test (QUV-B), as follows:

[0113] 1. Test method: GB / T 14522-2008.

[0114] 2. Test conditions: Exposure cycle type 7, as shown in Table 3.

[0115] Table 3 Test conditions for fluorescent UV lamp exposure test

[0116] 3. Test time: 3000h.

[0117] 4. Testing equipment: UV QUV / SPRAY, model: 20-36601-93-SPRAY.

[0118] 5. Test results: As shown in Table 4 and Figures 5 to 6, Figure 5 is a UV aging test diagram of the material prepared in Example 1, and Figure 6 is a UV aging test diagram of the material prepared in Comparative Example 1. It can be seen from Table 4 and Figures 5 to 6 that the strontium titanate nanomaterial prepared in Example 1 of the present invention and the photovoltaic competitor powder sample in Comparative Example 1 both passed the UV aging test (QUV-B) for 3000 hours, but the yellowing resistance of the strontium titanate nanomaterial prepared in Example 1 is better than that of the photovoltaic competitor powder sample in Comparative Example 1.

[0119] Table 4 UV aging test results

[0120] Note: △b means yellowing.

[0121] Comparative Example 2

[0122] Strontium titanate nanomaterials were prepared according to the method of Example 1, except that the strontium titanate nano-additive used in this comparative example was octahedral strontium titanate.

[0123] Comparative Example 3

[0124] Strontium titanate nanomaterials were prepared according to the method of Example 1, except that the strontium titanate nano-additive used in this comparative example was hexahedral strontium titanate.

[0125] Comparative Example 4

[0126] Strontium titanate nanomaterials were prepared according to the method of Example 1, except that the strontium titanate nano-additive used in this comparative example was irregular strontium titanate.

[0127] Comparative Example 5

[0128] Strontium titanate nanomaterials were prepared according to the method of Example 1, except that the strontium titanate nano-additive used in this comparative example was a mixture of octahedral strontium titanate and hexahedral strontium titanate in a mass ratio of 1:1.

[0129] Comparative Example 6

[0130] Strontium titanate nanomaterials were prepared according to the method of Example 1, except that the strontium titanate nano-additive used in this comparative example was a mixture of octahedral strontium titanate and irregular strontium titanate in a mass ratio of 1:1.

[0131] Comparative Example 7

[0132] Strontium titanate nanomaterials were prepared according to the method of Example 1, except that the strontium titanate nano-additive used in this comparative example was a mixture of hexahedral strontium titanate and irregular strontium titanate in a mass ratio of 1:1.

[0133] Comparative Example 8

[0134] Strontium titanate nanomaterials were prepared according to the method of Example 1, except that the strontium titanate nano-additive used in this comparative example was a mixture of octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate in a mass ratio of 1:1:1.

[0135] Comparative Example 9

[0136] Strontium titanate nanomaterials were prepared according to the method of Example 1, except that the strontium titanate nano-additive used in this comparative example was a mixture of octahedral strontium titanate and hexahedral strontium titanate in a mass ratio of 3:6.

[0137] Test Example 4

[0138] The materials prepared in the embodiments and comparative examples were subjected to UV aging tests according to the method of Test Example 3. The test time in this test example was 2000 h. The specific results are shown in Table 5 and Figures 7 to 9, wherein Figure 7 is a UV aging test diagram of the materials prepared in Example 1, Comparative Example 2, and Comparative Example 3 (from left to right, they are Example 1, Comparative Example 2, and Comparative Example 3), Figure 8 is a UV aging test diagram of the materials prepared in Comparative Example 4, Comparative Example 5, and Comparative Example 6 (from left to right, they are Comparative Example 4, Comparative Example 5, and Comparative Example 6), and Figure 9 is a UV aging test diagram of the materials prepared in Comparative Example 7, Comparative Example 8, and Comparative Example 9 (from left to right, they are Comparative Example 7, Comparative Example 8, and Comparative Example 9). It can be seen from Table 5 and Figures 7 to 9 that, compared with the comparative example, the strontium titanate nanomaterial prepared in Example 1 of the present invention using appropriately proportioned octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate as strontium titanate nano-additives has the best light retention rate and low yellowing value.

[0139] Table 5 UV aging test results

[0140] Note: △b means yellowing.

[0141] Test Example 5

[0142] The materials prepared in the embodiments and comparative examples were subjected to a neutral salt spray (NSS) test with reference to the method of Test Example 1. The test time in this test example was 1000 h. The specific results are shown in Table 6 and Figures 10 to 12, wherein Figure 10 is a neutral salt spray test diagram of the materials prepared in Example 1, Comparative Example 2, and Comparative Example 3 (from left to right, Example 1, Comparative Example 2, and Comparative Example 3), Figure 11 is a neutral salt spray test diagram of the materials prepared in Comparative Example 4, Comparative Example 5, and Comparative Example 6 (from left to right, Comparative Example 4, Comparative Example 5, and Comparative Example 6), and Figure 12 is a neutral salt spray test diagram of the materials prepared in Comparative Example 7, Comparative Example 8, and Comparative Example 9 (from left to right, Comparative Example 7, Comparative Example 8, and Comparative Example 9). As can be seen from Table 6 and Figures 10 to 12, the paint film of the nanomaterial in Comparative Example 4, which only uses irregular strontium titanate as a strontium titanate nano-additive, has a large area of ​​rust and poor neutral salt spray resistance.

[0143] Table 6 Neutral salt spray test results

[0144] Test Example 6

[0145] The materials prepared in the examples and comparative examples were subjected to a heat and humidity resistance test (temperature of 85°C and relative humidity of 85% RH) according to the method of Test Example 2. The test time in this test example was 1480 hours. The specific results are shown in Table 7. As can be seen from Table 7, compared with the comparative example, the strontium titanate nanomaterial prepared in Example 1 of the present invention using a suitable ratio of octahedral strontium titanate, hexahedral strontium titanate, and irregular strontium titanate as strontium titanate nano-additives has the best light retention rate and low color difference and yellowing values.

[0146] Table 7 Humidity and heat resistance test results

[0147] Note: △E is color difference, △b is yellowing.

[0148] Comparative Example 10

[0149] The coating was prepared according to the method of Example 1, except that no strontium titanate nano-additive was added in this comparative example.

[0150] Test Example 7

[0151] The strontium titanate nanomaterials prepared in Example 1 and Comparative Examples 2 to 4, and the coating prepared in Comparative Example 10, were subjected to transient photocurrent response tests using xenon lamp illumination and an electrochemical workstation, specifically the intensity of the photocurrent, and the results are shown in Table 8. As can be seen from Table 8, the coating samples without strontium titanate had no photocurrent, and the photocurrent intensities of the strontium titanate nanomaterials obtained by adding strontium titanate with different morphologies were different. Among them, the photocurrent of the strontium titanate nanomaterial prepared in Comparative Example 2 (adding octahedral strontium titanate) was the strongest, the photocurrent of the strontium titanate nanomaterial prepared in Comparative Example 4 (adding irregular strontium titanate) was the weakest, and the photocurrent of the strontium titanate nanomaterial prepared in Example 1 was 0.279 μA.

[0152] Table 8 Transient photocurrent response test results

[0153] It can be seen from the above test examples that the strontium titanate nanomaterial provided by the present invention has excellent resistance to ultraviolet aging, neutral salt spray resistance and moisture and heat resistance. At the same time, the addition of strontium titanate nano-additives is also beneficial to improving the photoelectric conversion efficiency of the strontium titanate nanomaterial, and is suitable for preparation into photovoltaic module packaging materials.

[0154] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A strontium titanate nanomaterial, wherein the raw materials for preparation include a base material and a dispersant, wherein the mass of the dispersant is 0.05 to 0.2% of the mass of the base material; The matrix material includes the following raw materials by weight: 50-90 parts of powdered resin; 10-50 parts of curing agent; 0-20 parts of antioxidant additives; Catalyst 0.05-0.2 parts; Surface conditioning agent 0-10 parts; Light stabilizer 0-20 parts; 0.05 to 5 parts of strontium titanate nano-additive, which is a mixture of octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate, and the mass ratio of the octahedral strontium titanate, hexahedral strontium titanate and irregular strontium titanate is 3 to 4:4 to 6:1 to 2.

2. The strontium titanate nanomaterial according to claim 1, characterized in that: The particle size of the strontium titanate nano-additive is 50-300nm.

3. The strontium titanate nanomaterial according to claim 2, characterized in that: The particle size of the octahedral strontium titanate is 100-200 nm; the particle size of the hexahedral strontium titanate is 100-200 nm; and the particle size of the irregular strontium titanate is 50-100 nm.

4. The strontium titanate nanomaterial according to claim 1, characterized in that: The powder resin includes one or more of acrylic resin, polyurethane resin and polyester resin.

5. The strontium titanate nanomaterial according to claim 4, characterized in that: The acrylic resin is an epoxy acrylic resin.

6. The strontium titanate nanomaterial according to claim 1, characterized in that: The curing agent includes one or more of dodecanedioic acid, triglycidyl isocyanurate and isocyanate.

7. The strontium titanate nanomaterial according to claim 1, characterized in that: The antioxidant auxiliary agent includes one or more of β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, benzofuranone derivatives and thioester antioxidants.

8. The strontium titanate nanomaterial according to claim 1, characterized in that: The catalyst includes tetrabutylammonium bromide, dibutyltin dilaurate or 2-propylimidazole.

9. The strontium titanate nanomaterial according to claim 1, characterized in that: The surface conditioning agent includes benzoin.

10. The strontium titanate nanomaterial according to claim 1, characterized in that: The light stabilizer includes a triazine light stabilizer or a hindered amine light stabilizer.

11. The strontium titanate nanomaterial according to any one of claims 1 to 10, characterized in that: The particle size of the matrix material is 30 to 150 μm.

12. The strontium titanate nanomaterial according to claim 1, characterized in that: The dispersant includes one or more of alumina, fumed silica and glass microspheres.

13. The strontium titanate nanomaterial according to claim 1 or 12, characterized in that: The particle size of the dispersant is 2 to 8 μm.

14. The method for preparing the strontium titanate nanomaterial according to any one of claims 1 to 13, comprising the following steps: The raw materials for preparing the matrix material are mixed, and the mixture is melt-extruded, cooled, crushed and sieved in sequence to obtain the matrix material; the matrix material is mixed with a dispersant to obtain the strontium titanate nano-micro material; Alternatively, the raw materials for preparing the matrix material are mixed with a dispersant, and then melt-extruded, cooled, crushed and sieved in sequence to obtain the strontium titanate nano-micro material.

15. The preparation method according to claim 14, characterized in that: The temperature of the melt extrusion is 90-130°C.

16. Use of the strontium titanate nanomaterial according to any one of claims 1 to 13 or the strontium titanate nanomaterial prepared by the preparation method according to claim 14 or 15 in photovoltaic module packaging materials.

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