Antioxidant light conversion microsphere, packaging adhesive film and photovoltaic module

Abstract

The invention relates to the technical field of photoelectricity, in particular to an antioxidant light conversion microsphere, a packaging adhesive film and a photovoltaic module. The antioxidant light conversion microsphere comprises an inner core and a shell layer coating the surface of the inner core, the inner core comprises first resin, first light conversion powder, an antioxidant and a first light stabilizer; the shell layer includes a second resin, an oxygen barrier, and an oxygen absorbent. By designing a special core-shell structure and adding a special functional component into the core-shell structure to achieve a synergistic effect with the first light conversion powder, the antioxidant light conversion microsphere disclosed by the invention can have an excellent light conversion function and antioxidant performance, and when the antioxidant light conversion microsphere is added into a packaging adhesive film, the overall antioxidant performance of the adhesive film can be improved.

Description

Technical Field

[0001] The present invention relates to the field of optoelectronic technologies, and particularly to an antioxidant light conversion microsphere, a packaging adhesive film, and a photovoltaic module. Background Art

[0002] A light conversion adhesive film is a special packaging adhesive film with a light conversion function, mainly used in the field of solar cells. As the core component in the light conversion adhesive film, the light conversion powder can effectively absorb ultraviolet light in sunlight, avoiding damage to the service life of photovoltaic devices; at the same time, it can convert ultraviolet light into available visible light, thereby improving the photoelectric conversion efficiency of photovoltaic devices.

[0003] However, the light conversion powder in the existing light conversion adhesive film has poor stability, mainly manifested as obvious attenuation when exposed to oxygen and ultraviolet light UV aging, which will cause damage to the battery chips in the solar modules using the light conversion adhesive film, further resulting in power loss of the modules. Summary of the Invention

[0004] The present invention provides an antioxidant light conversion microsphere and its preparation method, a packaging adhesive film, and a photovoltaic module to solve the problem of poor stability of the light conversion powder used in the existing light conversion adhesive film.

[0005] The present invention provides an antioxidant light conversion microsphere, including a core and a shell layer coated on the surface of the core; the core includes a first resin, a first light conversion powder, an antioxidant, and a first light stabilizer; the shell layer includes a second resin, an oxygen barrier agent, and an oxygen absorber.

[0006] Further, by weight, the core includes: 92.0 - 98.4 parts of the first resin, 0.1 - 2.0 parts of the first light conversion powder, 1.0 - 3.0 parts of the antioxidant, and 0.5 - 3.0 parts of the first light stabilizer.

[0007] Preferably, the weight ratio of the antioxidant to the first light stabilizer is 1:3 - 5:1.

[0008] Further, by weight, the shell layer includes 85.0 - 93.0 parts of the second resin, 2.0 - 4.0 parts of the oxygen barrier agent, and 5.0 - 11.0 parts of the oxygen absorber.

[0009] Preferably, the particle size of the oxygen barrier agent is 20 - 50 nm; the particle size of the oxygen absorber is 20 - 50 nm.

[0010] Further, the shell layer further includes a second light conversion powder, and the addition amount of the second light conversion powder is 0.01 - 2% of the mass of the second resin.

[0011] Preferably, the second light conversion powder is an organic light conversion powder; more preferably, the second light conversion powder is selected from one or more of rare earth organic complexes, triazine-based organic light conversion agents, and benzotriazole-based organic light conversion agents.

[0012] Further, the first resin and the second resin are each independently selected from one or more of PMMA resin, EVA resin, acrylic resin, or epoxy resin.

[0013] Further, the first light conversion powder is an organic light conversion powder.

[0014] Preferably, the first light conversion powder is selected from one or more of benzotriazole-based organic light conversion agents, triazine-based organic light conversion agents, and thiophene-based organic light conversion agents.

[0015] Further, the antioxidant is selected from one or more of pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,6-di-tert-butyl-4-methylphenol, C13-15 branched and linear alkyl esters of 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid, tris(2,4-di-tert-butylphenyl) phosphite, or bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite.

[0016] Further, the first light stabilizer is selected from one or more of 2-(2-hydroxyphenyl)-benzotriazole, polymer of succinic acid and (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol), N,N-bis(2,2,6,6-tetramethyl-4-piperidyl)-1,3-benzenedicarboxamide, 2,2,6,6-tetramethylpiperidineamine, 1,3-diphenylisobenzofuran, or 9,10-anthracenediyl-bis(methylenedipropanedioic acid).

[0017] Further, the oxygen absorber is selected from one or more of magnesium silicide, iron powder, sodium dithionite, and sodium sulfite.

[0018] Further, the oxygen barrier agent is selected from one or more of montmorillonite, hydrotalcite, alumina, and silica.

[0019] Further, the particle size of the core is 150 - 300 μm, preferably 200 - 300 μm; the thickness of the shell layer is 0.5 - 6 μm.

[0020] According to the second aspect of the present invention, the present invention also provides an encapsulating adhesive film, comprising the above-mentioned antioxidant light conversion microspheres.

[0021] Further, by weight parts, the encapsulation film comprises 95 - 99.68 parts of a third resin, 0.1 - 1 part of a crosslinking agent, 0.1 - 1 part of a co - crosslinking agent, 0.1 - 1 part of a silane coupling agent, 0.1 - 1 part of a second light stabilizer, and 0.01 - 2 parts of antioxidant and light - conversion microspheres.

[0022] Preferably, the third resin is at least one of ethylene - vinyl acetate copolymer, ethylene - propylene copolymer, ethylene - butene copolymer, ethylene - octene copolymer, and ethylene - methyl methacrylate copolymer.

[0023] According to the third aspect of the present invention, the present invention provides a photovoltaic module, comprising the above - mentioned encapsulation film.

[0024] The antioxidant and light - conversion microspheres provided by the present invention have a core - shell structure, including a core and a shell layer coated on the surface of the core. By designing a special core - shell structure and adding special functional components to the core - shell structure, and synergistically acting with the first light - conversion powder, the antioxidant and light - conversion microspheres of the present invention have excellent light - conversion function and antioxidant performance. Adding them to the encapsulation film can improve the overall antioxidant performance of the film. Description of the Drawings

[0025] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0026] Figure 1 is one of the structural schematic diagrams of the antioxidant and light - conversion microspheres provided by the embodiments of the present invention.

[0027] Figure 2 is the second of the structural schematic diagrams of the antioxidant and light - conversion microspheres provided by the embodiments of the present invention.

[0028] Reference numerals: 1: core; 2: shell layer. Detailed Embodiments

[0029] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will clearly and completely describe the technical solutions in the present invention in conjunction with the drawings in the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

[0030] In the first typical embodiment of the present invention, as Figure 1 and Figure 2As shown in the figure, the present invention provides an antioxidant and light conversion microsphere, which includes a core 1 and a shell layer 2 coated on the surface of the core; the core 1 includes a first resin, a first light conversion powder, an antioxidant, and a first light stabilizer; the shell layer 2 includes a second resin, an oxygen barrier agent, and an oxygen absorber.

[0031] It should be noted that the way the shell layer coats the core can be complete coating (as shown in Figure 1 the figure) or dot coating (as shown in Figure 2 the figure). For the core-shell microsphere with complete coating, its shell layer evenly covers the surface of the core, forming a continuous and dense shell layer. For the core-shell microsphere with dot coating, its shell layer is discontinuously distributed on the surface of the core, forming a dot-like or island-like structure.

[0032] The antioxidant and light conversion microsphere of the present invention has a core-shell structure, including a core and a shell layer coated on the surface of the core. The first light conversion powder, antioxidant, and first light stabilizer in the core are dispersed or dissolved in the first resin. The first resin can protect the first light conversion powder, protecting it from the influence of oxygen and moisture in the environment, thereby improving its aging resistance and reducing the reduction of light conversion efficiency after aging. The resin coating can also effectively solve the problem of agglomeration of ultrafine powders, improve the dispersibility of the first light conversion powder, and improve the application performance of the light conversion powder. The antioxidant can effectively delay the oxidation process, protect the first light conversion powder from oxidation damage, and improve the stability and service life of the first light conversion powder. The first light stabilizer protects the first light conversion powder through multiple mechanisms such as ultraviolet light absorption, energy conversion, free radical scavenging, and energy transfer, improving the light stability and photoelectric conversion efficiency of the first light conversion powder and extending its service life. The shell layer can protect the core. The shell layer includes a second resin, an oxygen barrier agent, and an oxygen absorber. The second resin further protects the first light conversion powder from the influence of oxygen and moisture in the environment. The oxygen barrier agent can block oxygen, and the oxygen absorber can absorb the oxygen entering the shell layer to prevent oxygen from entering the core. The second resin can also play a role in carrying and dispersing the oxygen barrier agent and the oxygen absorber, enabling the oxygen barrier agent and the oxygen absorber to more effectively exert their functions. By designing a special core-shell structure and adding special functional components in the core-shell structure, and synergistically acting with the first light conversion powder, the antioxidant and light conversion microsphere of the present invention can have excellent light conversion function and antioxidant performance. Adding it to EVA or POE films can improve the overall antioxidant performance of the films.

[0033] According to some specific embodiments of the present invention, by weight, the core includes: 92.0 - 98.4 parts of the first resin, 0.1 - 2.0 parts of the first light conversion powder, 1.0 - 3.0 parts of the antioxidant, and 0.5 - 3.0 parts of the first light stabilizer.

[0034] By limiting the amounts of the first resin, the first light conversion powder, the antioxidant, and the first light stabilizer in the core within reasonable range values, the components can play better roles, the synergistic effect among the components can be improved, and the stability of the first light conversion powder can be better enhanced.

[0035] Preferably, the weight ratio of the antioxidant to the first light stabilizer is 1:3 - 5:1. Selecting the antioxidant and the first light stabilizer with the above weight ratio helps to fully exert their synergistic effect, thereby improving the stability of the first light conversion powder. More preferably, the weight ratio of the antioxidant to the first light stabilizer is 1:(1 - 2.5).

[0036] According to some specific embodiments of the present invention, by weight, the shell layer comprises 85.0 - 93.0 parts of a second resin, 2.0 - 4.0 parts of an oxygen barrier agent, and 5.0 - 11.0 parts of an oxygen scavenger.

[0037] By limiting the amounts of the second resin, the oxygen barrier agent, and the oxygen scavenger in the shell layer within reasonable range values, the components can play better roles, the synergistic effect among the components can be improved, the shell layer can better protect the core, and better oxygen barrier and oxygen scavenging effects can be achieved.

[0038] Preferably, the particle size of the oxygen barrier agent is 20 - 50 nm; the particle size of the oxygen scavenger is 20 - 50 nm. The oxygen barrier agent and the oxygen scavenger within the above particle size range can be better dispersed in the second resin, improving the compatibility between the oxygen barrier agent and the oxygen scavenger and the second resin, better realizing the oxygen barrier and oxygen scavenging functions, and at the same time not affecting the light conversion performance of the first light conversion powder in the core.

[0039] According to some specific embodiments of the present invention, the shell layer further comprises a second light conversion powder, and the addition amount of the second light conversion powder is 0.01 - 2% of the mass of the second resin; adding the second light conversion powder in the shell layer can further improve the light conversion performance of the antioxidant light conversion microspheres. The addition amount of the second light conversion powder needs to be limited within a reasonable range. When the addition amount of the second light conversion powder exceeds 2% of the mass of the second resin, agglomeration may occur, reducing the dispersibility of the second light conversion powder and affecting its conversion efficiency and the overall performance of the antioxidant light conversion microspheres.

[0040] Preferably, the second light conversion powder is an organic light conversion powder. More preferably, the second light conversion powder is selected from one or more of rare earth organic complexes, triazine - type organic light conversion agents, and benzotriazole - type organic light conversion agents.

[0041] Preferably, the general formula of the rare earth organic complex is: RE x M 1-x (TTA) m Q n, where RE is a rare earth element, which can be one of Sm, Eu, and Ce; M is at least one of La, Gd, or Y, and 0 < x < 1; TTA is α-thiophenecarbonyltrifluoroacetone, m = 2 - 3; Q is at least one of o-phenanthroline, 2,2'-bipyridine, tri-n-octylphosphine oxide, or triphenylphosphine oxide, and n = 1 - 3.

[0042] Preferably, the structure of the triazine-based organic light conversion agent is as follows: ; Among them, R1, R2, and R3 are each independently selected from H, halogen, amino, carboxyl, aldehyde, hydroxyl, nitro, cyano, trifluoromethyl, trifluoromethoxy, substituted or unsubstituted C1-C20 straight-chain alkyl, substituted or unsubstituted C3-C20 branched-chain alkyl, substituted or unsubstituted C2-C20 heteroalkyl, substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C2-C20 alkenyl, substituted or unsubstituted C6-C40 aryl, substituted or unsubstituted C4-C40 heteroaryl, substituted or unsubstituted C2-C20 ester group, substituted or unsubstituted C1-C20 amino group, substituted or unsubstituted C1-C20 acylamino group, substituted or unsubstituted C3-C20 cyclic acylamino group, substituted or unsubstituted C3-C20 cyclic imide group, substituted or unsubstituted C1-C20 acyl group.

[0043] Preferably, the light conversion agent is a benzotriazole derivative, and the general structural formula of the benzotriazole derivative is as follows: ; Among them, the R substituent is And at least one R substituent is present at the 4 and 7 positions of the benzotriazole derivative, and at least one R substituent is present at the 5 and 6 positions of the benzotriazole derivative; R1 and R2 are each independently selected from H, substituted or unsubstituted C1-C20 alkyl, C3-C20 alkyl in which at least one methylene group is replaced by -COO- or -O-, and substituted or unsubstituted C2-C20 alkenyl, where the substituents in R1 and R2 are each independently selected from any one or more of methyl, ethyl, propyl, butyl, trifluoromethyl, and nitro.

[0044] According to some specific embodiments of the present invention, the first resin and the second resin are each independently selected from one or more of PMMA resin, EVA resin, acrylic resin, or epoxy resin.

[0045] According to some specific embodiments of the present invention, the first light conversion powder is an organic light conversion powder. The organic light conversion powder may include benzotriazole derivatives, triazine organic compounds, thiophene organic light conversion agents, etc. Preferably, the first light conversion powder is selected from one or more of benzotriazole derivatives.

[0046] According to some specific embodiments of the present invention, the antioxidant is selected from one or more of pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,6-di-tert-butyl-4-methylphenol, C13-15 branched and linear alkyl esters of 3,5-bis(1,1-dimethylethyl)-4-hydroxybenzenepropanoic acid, tris(2,4-di-tert-butylphenyl) phosphite, or bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite.

[0047] According to some specific embodiments of the present invention, the first light stabilizer is selected from one or more of 2-(2-hydroxyphenyl)-benzotriazole, the polymer of succinic acid and (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol), N,N-bis(2,2,6,6-tetramethyl-4-piperidyl)-1,3-benzenedicarboxamide, 2,2,6,6-tetramethylpiperidineamine, 1,3-diphenylisobenzofuran, or 9,10-anthracenediyl-bis(methylene)dimalonic acid; According to some specific embodiments of the present invention, the oxygen scavenger is selected from one or more of magnesium silicide, iron powder, sodium dithionite, and sodium sulfite; According to some specific embodiments of the present invention, the oxygen barrier agent is selected from one or more of montmorillonite, hydrotalcite, alumina, and silica.

[0048] According to some specific embodiments of the present invention, the particle size of the core is 150 - 300 μm, preferably 200 - 300 μm; the thickness of the shell layer is 0.5 - 6 μm. Defining the core particle size and shell layer thickness of the antioxidant light conversion microspheres within a reasonable range can optimize the light conversion function, antioxidant performance, and mechanical properties of the antioxidant light conversion microspheres, and further improve the optical properties, mechanical properties, and stability of the film prepared therefrom.

[0049] The above antioxidant light conversion microspheres of the present invention can be prepared by methods commonly used by those skilled in the art for preparing core-shell microspheres. For example: seed polymerization method, emulsion polymerization method, self-assembly method, stepwise heterocoagulation method, template method, deposition method, and suspension method, etc.

[0050] According to some specific embodiments of the present invention, the preparation method of the above antioxidant light conversion microspheres of the present invention includes the following steps: Preparation of the first resin microspheres: Dissolve the first light stabilizer, the first light conversion powder, and the antioxidant in the first curing agent or the first initiator. After ultrasonic dispersion to uniformity, a first dispersion liquid is formed.

[0051] Add the emulsifier to water. After stirring evenly at 80 - 90 °C, add the first resin monomer and place it in a homogenizing emulsifier to form an oil-in-water emulsion. Then continue to stir in a water bath at 80 - 90 °C to form a first emulsion liquid.

[0052] Add the above-mentioned first dispersion liquid to the first emulsion liquid, and cure at 80 - 90 °C for 1 - 3 h to obtain the first resin microspheres containing the first light conversion powder. The average particle size of the prepared first resin microspheres is 150 - 300 μm. Place the first resin microspheres in an oven at 40 - 50 °C and dry for 12 - 36 h, then take them out for standby.

[0053] Preparation of the antioxidant light conversion microspheres: Dissolve the second curing agent or the second initiator, the oxygen absorber, the oxygen barrier agent, and the first resin microspheres by ultrasonic dispersion to uniformity to form a second dispersion liquid.

[0054] Add the emulsifier to water. After stirring evenly at 80 - 90 °C, add the second resin monomer and place it in a homogenizing emulsifier to form an oil-in-water emulsion. Then continue to stir in a water bath at 80 - 90 °C to form a second emulsion liquid.

[0055] Add the second dispersion liquid to the second emulsion liquid, and cure at 80 - 90 °C for 1 - 3 h to obtain the antioxidant light conversion microspheres. Place the antioxidant light conversion microspheres in an oven at 40 - 50 °C and dry for 12 - 36 h, then take them out for standby.

[0056] In the above preparation method, the first resin is formed by polymerization of the first resin monomer under the action of the first curing agent or the first initiator. When the first resin is PMMA resin or EVA resin, the first resin monomer is polymerized under the action of the first initiator, and the first initiator can be an azo initiator or a redox initiator; when the first resin is acrylic resin or epoxy resin, the first resin monomer is polymerized under the action of the first curing agent, and the first curing agent can be m-xylenediamine (MXDA), diethylenetriamine (DETA), or triethylenetetramine (TETA).

[0057] Similarly, the second resin is formed by polymerization of the second resin monomer under the action of the second curing agent or the second initiator. When the second resin is PMMA resin or EVA resin, the second resin monomer is polymerized under the action of the second initiator, and the second initiator can be an azo initiator or a redox initiator; when the second resin is acrylic resin or epoxy resin, the second resin monomer is polymerized under the action of the second curing agent, and the second curing agent can be m-xylenediamine (MXDA), diethylenetriamine (DETA), or triethylenetetramine (TETA).

[0058] In the above preparation method, the first emulsifier and the second emulsifier can each independently be: OP-10, EL-40 or Tween-80.

[0059] In the second typical embodiment of the present invention, the present invention also provides a packaging adhesive film, including the above-mentioned antioxidant and light conversion microspheres.

[0060] The light conversion adhesive film obtained by using the above-mentioned antioxidant and light conversion microspheres has excellent stability, antioxidant performance and light conversion performance, and can play a role effectively for a long time, thereby improving the service life of photovoltaic modules.

[0061] According to some specific embodiments of the present invention, by weight, the packaging adhesive film includes 95-99.68 parts of a third resin, 0.1-1 part of a crosslinking agent, 0.1-1 part of a co-crosslinking agent, 0.1-1 part of a silane coupling agent, 0.1-1 part of a second light stabilizer, and 0.01-2 parts of antioxidant and light conversion microspheres. By limiting the amounts of the components in the packaging adhesive film within reasonable range values, better synergistic effects can be achieved among the components, improving the overall performance of the packaging adhesive film.

[0062] Preferably, the third resin is at least one of ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-octene copolymer, and ethylene-methyl methacrylate copolymer. The above types of resins have good bonding properties, meet the packaging performance of the adhesive film, and also have better compatibility with the antioxidant and light conversion microspheres, enabling the antioxidant and light conversion microspheres to better exert their light conversion efficiency and enhancing the overall performance of the packaging adhesive film.

[0063] The crosslinking agent can be one or more of isopropyl percarbonate tert-butyl, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, tert-butyl percarbonate-2-ethylhexyl, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(tert-amylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(tert-amylperoxy)cyclohexane, 1,1-bis(tert-butylperoxy)cyclohexane, 2,2-bis(tert-butylperoxy)butane, tert-amyl percarbonate 2-ethylhexyl, 2,5-dimethyl 2,5-bis(benzoylperoxy)-hexane, tert-amyl percarbonate, tert-butyl percarbonate 3,3,5 trimethylhexanoate.

[0064] The co-crosslinking agent can be one or more of tris(2-hydroxyethyl)isocyanurate triacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetraacrylate, ethoxylated pentaerythritol tetraacrylate, trimethylolpropane tetraacrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, ethoxylated glycerol triacrylate, propoxylated glycerol triacrylate, bis-trimethylolpropane tetraacrylate, bis-trimethylolpropane tetramethacrylate, propoxylated pentaerythritol tetraacrylate, 2,4,6-tris(2-propenyloxy)-1,3,5-triazine, tricyclodecane dimethanol diacrylate, propoxylated neopentyl glycol diacrylate, ethoxylated bisphenol A diacrylate, ethoxylated bisphenol A dimethacrylate, 2-butyl-2-ethyl-1,3-propanediol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate.

[0065] The silane coupling agent can be one or more of γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, vinyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane.

[0066] The second light stabilizer can be one or more of bis(2,2,6,6-tetramethylpiperidinol) sebacate, 2,4-dichloro-6-(4-morpholinyl)-1,3,5-triazine, bis-1-decyloxy-2,2,6,6-tetramethylpiperidin-4-yl sebacate, the polymer of succinic acid and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol, the polymer of N,N’-bis(2,2,6,6-tetramethyl-4-piperidyl)-1,6-hexanediamine and 2,4-dichloro-6-(1,1,3,3-tetramethylbutyl)amino-1,3,5-triazine, the polymer of N,N’-bis(2,2,6,6-tetramethyl-4-piperidyl)-1,6-hexanediamine and 2,4-dichloro-6-(4-morpholinyl)-1,3,5-triazine, the polymer of N,N’-bis(1,2,2,6,6-pentamethyl-4-piperidyl)-1,6-hexanediamine and morpholine-2,4,6-trichloro-1,3,5-triazine, the complex of bis(1,2,2,6,6-pentamethyl-4-piperidyl) sebacate / methyl-1,2,2,6,6-pentamethyl-4-piperidyl sebacate or the polymer of succinic acid and (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol). Preferably, it is bis(2,2,6,6-tetramethylpiperidinol) sebacate or 2,4-dichloro-6-(4-morpholinyl)-1,3,5-triazine.

[0067] In the third typical embodiment of the present invention, the present invention further provides a photovoltaic module, including the above encapsulation adhesive film.

[0068] The photovoltaic module including the above encapsulation adhesive film of the present invention has excellent photoelectric conversion efficiency and antioxidant performance. Of course, there can be more choices according to different needs and application scenarios. The encapsulation adhesive film of the present invention is not limited to photovoltaic devices, agricultural films, building glass and other fields.

[0069] The beneficial effects of the present invention will be described below in conjunction with specific examples and comparative examples.

[0070] The raw materials used in the following examples and comparative examples are specifically as follows: First resin: bisphenol A diglycidyl ether; First light stabilizer: 2,2,6,6-tetramethylpiperidineamine; First light conversion powder: benzotriazole derivatives, specifically: ; First curing agent: m-xylylenediamine (MXDA); Antioxidant: pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]; Emulsifier: Tween-80; Second resin: bisphenol A diglycidyl ether; Second curing agent: m-xylylenediamine (MXDA); Oxygen absorber: magnesium silicide with a particle size of 20 - 50 nm; Oxygen barrier agent: montmorillonite with a particle size of 20 - 50 nm; Second light conversion powder: benzotriazole derivatives, specifically: .

[0071] Example 1 This example provides an antioxidant and light conversion microsphere, as Figure 1 shown. The antioxidant and light conversion microsphere includes a core 1 and a shell layer 2 coated on the surface of the core 1. Among them, the component compositions of the core and the shell layer are shown in Table 1 below.

[0072] The preparation method of the antioxidant and light conversion microsphere is as follows: (1) Preparation of the first resin microsphere: Dissolve the first light stabilizer, the first light conversion powder and the antioxidant in the first curing agent, and ultrasonically disperse them evenly to form a first dispersion liquid.

[0073] Add the emulsifier to water, stir evenly at 85 °C, then add the first resin monomer and place it in a homogenizing emulsifier to emulsify to form an oil-in-water emulsion, and continue to stir in a water bath at 85 °C to form a first emulsion.

[0074] Add the above first dispersion liquid into the first emulsion, and cure it at 85 °C for 2 h to obtain the first resin microspheres containing the first light conversion powder. Place the first resin microspheres in an oven at 40 - 50 °C and dry them for 24 h, then take them out for standby.

[0075] (2) Preparation of antioxidant light conversion microspheres: Add the second curing agent, oxygen absorber, oxygen barrier agent, and the first resin microspheres, and ultrasonically disperse them evenly to form a second dispersion liquid.

[0076] Add the emulsifier into water, stir evenly at 85 °C, then add the second resin monomer and place it in a homogenizing emulsifier to emulsify to form an oil-in-water emulsion, and continue to stir in a water bath at 85 °C to form a second emulsion.

[0077] Add the second dispersion liquid into the second emulsion, and cure it at 85 °C for 2 h to obtain the antioxidant light conversion microspheres. Place the antioxidant light conversion microspheres in an oven at 40 - 50 °C and dry them for 24 h, then take them out for standby.

[0078] Example 2 - 11 Examples 2 - 11 each independently provide an antioxidant light conversion microsphere, which is different from Example 1 only in that: the dosages of the antioxidant and the first light stabilizer in the core are different. The specific differences are shown in Table 1 below. The dosages of each raw material in Table 1 are in parts by weight.

[0079] Examples 12 - 13 Examples 12 - 13 each independently provide an antioxidant light conversion microsphere, which is different from Example 1 only in that: the dosage of the first resin in the core is different. The specific differences are shown in Table 1 below.

[0080] Examples 14 - 15 Examples 14 - 15 each independently provide an antioxidant light conversion microsphere, which is different from Example 1 only in that: the dosage of the first light conversion powder in the core is different. The specific differences are shown in Table 1 below.

[0081] Comparative Example 1 Comparative Example 1 provides an antioxidant light conversion microsphere, which is different from Example 1 only in that: the first light stabilizer is not added to the core.

[0082] Examples 16 - 19 Examples 16 - 19 each independently provide an antioxidant light conversion microsphere, which is different from Example 1 only in that: the dosage of the oxygen barrier agent in the shell is different. The specific differences are shown in Table 2 below. The dosages of each raw material in Table 2 are in parts by weight.

[0083] Examples 20 - 22 Examples 20 - 22 each independently provide an antioxidant light conversion microsphere, which is different from Example 1 only in that the dosage of the oxygen absorber in the shell layer is different. The specific differences are shown in Table 2 below.

[0084] Examples 23 - 24 Examples 23 - 24 each independently provide an antioxidant light conversion microsphere, which is different from Example 1 only in that the dosage of the second resin in the shell layer is different. The specific differences are shown in Table 2 below.

[0085] Examples 25 - 26 Examples 25 - 26 each independently provide an antioxidant light conversion microsphere, which is different from Example 1 only in that the shell layer further includes a second light conversion powder. The specific differences are shown in Table 2 below.

[0086] Comparative Example 2 Comparative Example 2 provides an antioxidant light conversion microsphere, which is different from Example 1 only in that no oxygen barrier agent is added to the shell layer.

[0087] The antioxidant light conversion microspheres of the examples and comparative examples were subjected to performance tests. The test method is as follows: Take antioxidant light conversion microspheres with the same mass fraction and prepare a packaging adhesive film through a casting machine according to the following formulation composition: By weight, the packaging adhesive film includes 99 parts of ethylene - octene copolymer as the third resin, 0.2 parts of cross - linker isopropyl peroxycarbonate tert - butyl, 0.2 parts of co - cross - linker trimethylolpropane triacrylate, 0.1 part of silane coupling agent γ - methacryloxypropyltrimethoxysilane, 0.1 part of the second light stabilizer bis(2,2,6,6 - tetramethylpiperidin - 4 - yl) sebacate, and 0.4 parts of the antioxidant light conversion microsphere.

[0088] The obtained packaging adhesive film was laminated, and the fluorescence spectrum of the adhesive film with the same thickness was measured. It was excited with 365 nm ultraviolet light, and the fluorescence intensity of the packaging adhesive film was measured and the fluorescence decay was calculated. The calculation formula for the fluorescence decay of the packaging adhesive film is as follows: ; In the above formula, I is the fluorescence decay rate of the packaging adhesive film; is the fluorescence intensity of the packaging adhesive film before aging; is the fluorescence intensity of the packaging adhesive film after aging, and x is the irradiation dose (for example, when the irradiated adhesive film receives an irradiation dose of UV1, x = 1).

[0089] The test results are shown in Table 1 and Table 2 respectively below.

[0090] Table 1

[0091] Table 2

[0092] It can be seen from the experimental data in Table 1 and Table 2 that by designing a special core-shell structure and adding special functional components to the core-shell structure, and through the synergistic effect with the first light conversion powder, the antioxidant light conversion microspheres of the present invention have excellent light conversion function and antioxidant performance. Adding them to the encapsulation film can improve the overall antioxidant performance of the film.

[0093] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some of the technical features. However, such modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An antioxidant light-converting microsphere, characterized in that: It comprises an inner core and a shell layer covering the inner core; the inner core comprises a first resin, a first light-converting powder, an antioxidant and a first light stabilizer; and the shell layer comprises a second resin, an oxygen barrier and an oxygen absorber.

2. The antioxidant light-converting microspheres according to claim 1, characterized in that: In terms of weight, the core includes: 92.0-98.4 parts of a first resin, 0.1-2.0 parts of a first light-converting powder, 1.0-3.0 parts of an antioxidant, and 0.5-3.0 parts of a first light stabilizer; Preferably, the weight ratio of the antioxidant to the first light stabilizer is 1:3-5:

1.

3. The antioxidant light-converting microspheres according to claim 1 or 2, characterized in that: In terms of weight, the shell layer includes 85.0-93.0 parts of the second resin, 2.0-4.0 parts of the oxygen barrier and 5.0-11.0 parts of the oxygen absorber; Preferably, the particle size of the oxygen inhibitor is 20-50 nm; the particle size of the oxygen absorber is 20-50 nm.

4. The antioxidant light-converting microspheres according to any one of claims 1 to 3, characterized in that: The shell layer further includes a second light-converting powder, and the added amount of the second light-converting powder is 0.01-2% of the mass of the second resin; Preferably, the second light conversion powder is an organic light conversion powder; more preferably, the second light conversion powder is selected from one or more of rare earth organic complexes, triazine organic light conversion agents, and benzotriazole organic light conversion agents.

5. The antioxidant light-converting microspheres according to claim 1, characterized in that: The first resin and the second resin are each independently selected from one or more of PMMA resin, EVA resin, acrylic resin or epoxy resin.

6. The antioxidant light-converting microspheres according to claim 1, characterized in that: The first light conversion powder is an organic light conversion powder; preferably, the first light conversion powder is selected from one or more of a benzotriazole organic light conversion agent, a triazine organic light conversion agent, and a thiophene organic light conversion agent; And / or, the antioxidant is selected from one or more of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester, β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate octadecyl alcohol ester, 2,6-di-tert-butyl-4-methylphenol, 3,5-bis(1,1-dimethylethyl)-4-hydroxyphenylpropionic acid C13-15 branched and linear alkyl ester, tris(2,4-di-tert-butylphenyl) phosphite or bis(2,4-di-tert-butylphenyl) pentaerythritol bis diphosphite; And / or, the first light stabilizer is selected from one or more of 2-(2-hydroxyphenyl)-benzotriazole, a polymer of succinic acid and (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol), N,N-bis(2,2,6,6-tetramethyl-4-piperidinyl)-1,3-benzenedicarbamide, 2,2,6,6-tetramethylpiperidinamine, 1,3-diphenylisobenzofuran or 9,10-anthracenediyl-bis(methylene)dimalonic acid; and / or, the oxygen absorbent is selected from one or more of magnesium silicide, iron powder, sodium dithionite and sodium sulfite; And / or, the oxygen barrier is selected from one or more of montmorillonite, hydrotalcite, alumina and silica.

7. The antioxidant light-converting microspheres according to any one of claims 1 to 6, characterized in that: The particle size of the core is 150-300 μm, preferably 200-300 μm; the thickness of the shell is 0.5-6 μm.

8. A packaging film, characterized in that: The invention comprises the antioxidant light-converting microspheres as described in any one of claims 1 to 7.

9. The packaging film according to claim 8, characterized in that: According to the weight parts, it includes 95-99.68 parts of the third resin, 0.1-1 parts of the cross-linking agent, 0.1-1 parts of the auxiliary cross-linking agent, 0.1-1 parts of the silane coupling agent, 0.1-1 parts of the second light stabilizer and 0.01-2 parts of the antioxidant light-converting microspheres; Preferably, the third resin is at least one of ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-octene copolymer and ethylene-methyl methacrylate copolymer.

10. A photovoltaic module, characterized in that: Comprising the encapsulation film according to claim 8 or 9.

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