Epe film, method for preparing the same, and photovoltaic module

Abstract

The present application relates to the field of photovoltaic technology, and especially to an EPE adhesive film, a preparation method thereof and a photovoltaic module. The EPE adhesive film comprises a first EVA layer, a POE layer and a second EVA layer arranged in sequence. The first EVA layer and the second EVA layer comprise EVA resin, crosslinking agent, co-crosslinking agent, antioxidant, light stabilizer, silane coupling agent and surfactant. The POE layer comprises POE resin, crosslinking agent, co-crosslinking agent, antioxidant, light stabilizer and silane coupling agent. The surfactant comprises at least one of alkyl glycoside surfactant, alkyl betaine surfactant and alkyl sodium sulfonate surfactant. The number of carbon atoms of alkyl in the surfactant is 6-24. In the adhesive film, the EVA layer and the POE layer have excellent bonding performance. In the case of low POE thickness, the corresponding module can meet the reliability test, and the cost of the adhesive film is reduced while the bonding performance of the adhesive film is ensured.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic technology, and in particular to an EPE film, its preparation method, and a photovoltaic module. Background Technology

[0002] EPE photovoltaic encapsulant film, combining the advantages of EVA and POE, is widely used in the encapsulation of photovoltaic modules. To meet module manufacturers' demands for cost reduction in photovoltaic encapsulant film, the thickness of the POE layer in EPE photovoltaic encapsulant film products on the market is gradually decreasing. With the reduction in the thickness of the POE layer in photovoltaic encapsulant film, the EVA layer and POE layer are prone to delamination during reliability testing of the corresponding modules, affecting the lifespan of the photovoltaic modules.

[0003] To address the current delamination problem, existing EPE photovoltaic films incorporate silane coupling agents in both the EVA and POE layers. The interaction between these silane coupling agents improves the bonding performance between the EVA and POE layers. However, due to the significant difference in resin polarity between the EVA and POE layers in the EPE film, the interaction between the silane coupling agents at the interface is difficult, resulting in poor adhesion.

[0004] In view of this, the present invention is hereby proposed. Summary of the Invention

[0005] One object of the present invention is to provide an EPE film with excellent adhesion between the EVA layer and the POE layer.

[0006] Another object of the present invention is to provide a method for preparing EPE film.

[0007] Another object of the present invention is to provide a photovoltaic module comprising the above-mentioned EPE film.

[0008] To achieve the above-mentioned objectives of the present invention, one aspect of the present invention provides an EPE film, comprising a first EVA layer, a POE layer, and a second EVA layer disposed sequentially.

[0009] The first EVA layer and the second EVA layer each independently comprise the following components by weight: 100 parts EVA resin, 0.5 to 1.5 parts crosslinking agent, 0.1 to 1 part co-crosslinking agent, 0.1 to 0.5 parts antioxidant, 0.1 to 1 part light stabilizer, 0.3 to 1.5 parts silane coupling agent, and 0.005 to 1 part surfactant;

[0010] The POE layer comprises the following components by weight: 100 parts POE resin, 0.5 to 1.5 parts crosslinking agent, 0.1 to 1 part co-crosslinking agent, 0.1 to 0.5 parts antioxidant, 0.1 to 1 part light stabilizer, and 0.3 to 1.5 parts silane coupling agent;

[0011] The surfactant includes at least one of alkyl glycoside surfactants, alkyl betaine surfactants, and sodium alkyl sulfonate surfactants; the alkyl group in the surfactant has 6 to 24 carbon atoms.

[0012] In a specific embodiment of the present invention, the alkyl glycoside surfactant is an alkyl glycoside with a carbon chain length of C6 to C18. Further, the alkyl glycoside includes at least one selected from hexyl glucoside, decyl glucoside, dodecyl glucoside, and octadecyl glucoside.

[0013] In a specific embodiment of the present invention, the alkyl betaine surfactant has the following general structural formula:

[0014]

[0015] Wherein, R1 is a straight-chain alkyl group with 6 to 22 carbon atoms, and R2 is an alkylene group with 1 to 5 carbon atoms. Further, the alkyl betaine surfactant includes hexyldimethyl betaine, dodecyldimethyl betaine, tetradecyldimethyl betaine, hexadecyldimethyl betaine, octadecyldimethyl betaine, and docosyldimethyl betaine.

[0016] In a specific embodiment of the present invention, the sodium alkyl sulfonate surfactant is a sodium alkyl sulfonate with a carbon chain length of C6 to C24. Further, the sodium alkyl sulfonate surfactant includes at least one selected from sodium hexyl sulfonate, sodium dodecyl sulfonate, sodium tetradecyl sulfonate, sodium hexadecyl sulfonate, and sodium tetracosyl sulfonate.

[0017] In a specific embodiment of the present invention, in the first EVA layer and the second EVA layer, the mass ratio of the silane coupling agent to the surfactant is 1:(0.05~0.6).

[0018] In a specific embodiment of the present invention, the thickness ratio of the first EVA layer, the POE layer, and the second EVA layer is (1-2):1:(1-2). Further, the thickness of the first EVA layer and the second EVA layer is 250-380 μm; the thickness of the POE layer is 80-140 μm.

[0019] In a specific embodiment of the present invention, the silane coupling agent includes at least one of γ-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, triacetoxyvinylsilane, vinyltri(2-methoxyethoxy)silane, and γ-(methacryloyloxy)propyltrimethoxysilane.

[0020] Another aspect of the present invention provides a method for preparing any of the above-described EPE films, comprising the following steps: co-extruding and casting according to the composition of the first EVA layer, the POE layer and the second EVA layer to obtain the EPE encapsulation film.

[0021] Another aspect of the present invention provides a photovoltaic module comprising any of the EPE films described above.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] (1) In the EPE film of the present invention, a surfactant with long-chain hydrophobic and hydrophilic structures is added to the EVA layer. The hydrophilic structure can promote the migration of the silane coupling agent in the EVA layer to the surface of the EVA layer in contact with the POE layer. The migration of the long-chain hydrophobic structure to the POE layer promotes the migration of the silane coupling agent in the POE layer to the surface of the POE layer. The silane coupling agent in the EVA layer and the POE layer interact at the interface, thereby improving the adhesion performance between the layers.

[0024] (2) In the EPE film of the present invention, the EVA layer and the POE layer have excellent bonding performance. When using a low POE thickness, the corresponding components can meet the reliability test, while reducing the cost of the film and ensuring the bonding performance of the film.

[0025] (3) The photovoltaic module using the EPE film of the present invention will not delaminate after PID-192h test, and the module power attenuation is <2%. Detailed Implementation

[0026] The technical solution of the present invention will be clearly and completely described below with reference to specific embodiments. However, those skilled in the art will understand that the embodiments described below are some embodiments of the present invention, but not all embodiments, and are only used to illustrate the present invention, and should not be regarded as limiting the scope of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall be followed. Where the manufacturers of reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0027] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientation or positional relationships, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] The present invention provides an EPE film comprising a first EVA layer, a POE layer and a second EVA layer arranged sequentially;

[0029] The first EVA layer and the second EVA layer each independently comprise the following components by weight: 100 parts EVA resin, 0.5 to 1.5 parts crosslinking agent, 0.1 to 1 part co-crosslinking agent, 0.1 to 0.5 parts antioxidant, 0.1 to 1 part light stabilizer, 0.3 to 1.5 parts silane coupling agent, and 0.005 to 1 part surfactant;

[0030] The POE layer comprises the following components by weight: 100 parts POE resin, 0.5 to 1.5 parts crosslinking agent, 0.1 to 1 part co-crosslinking agent, 0.1 to 0.5 parts antioxidant, 0.1 to 1 part light stabilizer, and 0.3 to 1.5 parts silane coupling agent;

[0031] Surfactants include at least one of alkyl glycoside surfactants, alkyl betaine surfactants, and sodium alkyl sulfonate surfactants; the alkyl group in the surfactant has 6 to 24 carbon atoms.

[0032] In the EPE film of the present invention, a surfactant with long-chain hydrophobic and hydrophilic structures is added to the EVA layer. The hydrophilic structure can promote the migration of silane coupling agent in the EVA layer to the surface of the EVA layer in contact with the POE layer. The migration of the long-chain hydrophobic structure to the POE layer promotes the migration of silane coupling agent in the POE layer to the surface of the POE layer. The silane coupling agent in the EVA layer and the POE layer interact at the interface, thereby improving the adhesion performance between the layers. Specifically, when the number of carbon atoms in the alkyl group of the surfactant is too small, the difference in hydrophilicity and hydrophobicity of the surfactant decreases, weakening its ability to promote the migration of silane coupling agent in the POE layer to the POE layer surface, resulting in a weak improvement in the interfacial interaction between the EVA layer and the POE layer. When the number of carbon atoms in the alkyl group of the surfactant is too large, although the difference in hydrophilicity and hydrophobicity of the surfactant increases, the interaction forces of the surfactant's own long-chain molecular structure limit its migration and diffusion to the POE layer, similarly weakening its ability to promote the migration of silane coupling agent in the POE layer to the POE layer surface, and failing to effectively improve the adhesion performance between the EVA layer and the POE layer.

[0033] In various embodiments, the number of carbon atoms in the alkyl group of the surfactant of the present invention may be 6, 8, 10, 12, 15, 18, 20, 24 or any combination thereof.

[0034] In different embodiments, the amounts of the remaining components in the first and second EVA layers, relative to 100 parts of EVA resin, can be as follows:

[0035] The amount of crosslinking agent can be 0.5 parts, 0.8 parts, 1 part, 1.2 parts, 1.5 parts, or any combination thereof;

[0036] The amount of the crosslinking agent can be 0.1 parts, 0.3 parts, 0.5 parts, 0.8 parts, 1 part, or any combination thereof;

[0037] The amount of antioxidant can be 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, or any combination thereof;

[0038] The amount of light stabilizer can be 0.1 parts, 0.3 parts, 0.5 parts, 0.8 parts, 1 part, or any combination thereof;

[0039] The amount of silane coupling agent can be 0.3 parts, 0.5 parts, 0.8 parts, 1 part, 1.2 parts, 1.5 parts, or any combination thereof;

[0040] The amount of surfactant can be 0.005 parts, 0.05 parts, 0.1 parts, 0.3 parts, 0.5 parts, 0.8 parts, 1 part, or any combination thereof.

[0041] It is understood that the compositions of the first EVA layer and the second EVA layer can be the same or different, as long as their compositions remain within the scope of this invention. To ensure low production costs and film stability, the compositions of the first EVA layer and the second EVA layer are the same. Furthermore, the EVA resin and POE resin used in this invention are the same EVA resin and POE resin used in conventional EPE films, and will not be described in detail here.

[0042] In different embodiments, the amounts of the remaining components in the POE layer, by weight, relative to 100 parts of POE resin, can be as follows:

[0043] The amount of crosslinking agent can be 0.5 parts, 0.8 parts, 1 part, 1.2 parts, 1.5 parts, or any combination thereof;

[0044] The amount of the crosslinking agent can be 0.1 parts, 0.3 parts, 0.5 parts, 0.8 parts, 1 part, or any combination thereof;

[0045] The amount of antioxidant can be 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, or any combination thereof;

[0046] The amount of light stabilizer can be 0.1 parts, 0.3 parts, 0.5 parts, 0.8 parts, 1 part, or any combination thereof;

[0047] The amount of silane coupling agent can be 0.3 parts, 0.5 parts, 0.8 parts, 1 part, 1.2 parts, 1.5 parts, or any combination thereof.

[0048] In a specific embodiment of the present invention, the alkyl glycoside surfactant is an alkyl glycoside with a carbon chain length of C6 to C18. Further, the alkyl glycoside includes at least one selected from hexyl glucoside, decyl glucoside, dodecyl glucoside, and octadecyl glucoside.

[0049] In different embodiments, the carbon chain length of the alkyl glycoside surfactant of the present invention can be a range of C6, C9, C10, C12, C15, C18 or any two thereof, preferably an alkyl glycoside of C6 to C12.

[0050] In a specific embodiment of the present invention, the alkyl betaine surfactant has the following general structural formula:

[0051]

[0052] Wherein, R1 is a straight-chain alkyl group with 6 to 22 carbon atoms, and R2 is an alkylene group with 1 to 5 carbon atoms. Further, the alkyl betaine surfactants include hexyl dimethyl betaine, dodecyl dimethyl betaine, tetradecyl dimethyl betaine, hexadecyl dimethyl betaine, octadecyl dimethyl betaine, and docosyl dimethyl betaine.

[0053] In different embodiments, in the alkyl betaine surfactant of the present invention, R1 can be a straight-chain alkyl group with a carbon number of 6, 8, 10, 12, 16, 18, 20, 22 or any combination thereof. For example, R1 is preferably a straight-chain alkyl group with a carbon number of 6 to 16, and more preferably a straight-chain alkyl group with a carbon number of 12 to 16. R2 can be an alkylene group with a carbon number of 1, 2, 3, 4, or 5, such as methylene.

[0054] In a specific embodiment of the present invention, the sodium alkyl sulfonate surfactant is a sodium alkyl sulfonate with a carbon chain length of C6 to C24. Further, the sodium alkyl sulfonate surfactant includes at least one selected from sodium hexyl sulfonate, sodium dodecyl sulfonate, sodium tetradecyl sulfonate, sodium hexadecyl sulfonate, and sodium tetracosyl sulfonate.

[0055] In different embodiments, the carbon chain length of the sodium alkyl sulfonate surfactant of the present invention can be a range of C6, C10, C12, C15, C18, C20, C24 or any two thereof, for example, the preferred carbon chain length is C12 to C16.

[0056] It is understood that the surfactants in this invention can be prepared in-house or can be conventional commercial products. For example, the alkyl betaine surfactant can be prepared by reacting R1N(CH3)2 with chloroacetic acid; the sodium alkyl sulfonate surfactant can be prepared by reacting brominated or chloroalkyl groups with sodium sulfite.

[0057] In a specific embodiment of the present invention, the mass ratio of silane coupling agent to surfactant in the first EVA layer and the second EVA layer is 1:(0.05~0.6).

[0058] Within a certain range, the ratio of silane coupling agent to surfactant can balance the promoting effect of surfactant on the bonding of the two silane coupling agents while avoiding changes in the internal structural properties of the film. For example, in different embodiments, the mass ratio of silane coupling agent to surfactant in the first and second EVA layers can be 1:0.05, 1:0.08, 1:0.1, 1:0.15, 1:0.2, 1:0.25, 1:0.3, 1:0.35, 1:0.4, 1:0.45, 1:0.5, 1:0.55, 1:0.6, or any combination thereof.

[0059] In a specific embodiment of the present invention, the thickness ratio of the first EVA layer, the POE layer, and the second EVA layer is (1-2):1:(1-2). Further, the thickness of the first EVA layer and the second EVA layer is 250-380 μm; the thickness of the POE layer is 80-140 μm.

[0060] In different embodiments, the thickness ratio of the first EVA layer and the second EVA layer to the POE layer can be 1:1, 1.2:1, 1.5:1, 1.8:1, 2:1, or any combination thereof. Specifically, the thickness of the first EVA layer and the second EVA layer can be 250μm, 260μm, 280μm, 300μm, 320μm, 350μm, 380μm, or any combination thereof, and the thickness of the POE layer can be 80μm, 90μm, 100μm, 120μm, 140μm, or any combination thereof. The EPE film of the present invention improves the adhesion performance between the EVA layer and the POE layer, meeting the reliability testing requirements of components with low POE layer thickness, reducing the cost of the film while ensuring no delamination.

[0061] In a specific embodiment of the present invention, the crosslinking agent includes at least one selected from 2-ethylhexyl carbonate tert-butyl peroxide, 3,5,5-trimethylhexanoate tert-butyl peroxide, benzoyl peroxide, 2,5-dimethyl-2,5-bis(benzoylperoxy)hexane and 1,1-di-tert-butylperoxide-3,3,5-trimethylcyclohexane.

[0062] In a specific embodiment of the present invention, the co-crosslinking agent includes at least one of ethylene glycol dimethacrylate, triallyl isocyanurate, diethylene glycol dimethacrylate, trimethylolpropane triacrylate, triallyl cyanurate, and ethoxylated trimethylolpropane triacrylate.

[0063] In specific embodiments of the present invention, the antioxidant includes at least one selected from the following: tri(nonylphenyl) phosphite, 2,6-di-tert-butyl-p-cresol, octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, tri(2,4-di-tert-butylphenyl) phosphite, 2,2'-methylenebis(4-methyl-6-tert-butylphenol), 2,2'-thiobis(4-methyl-6-tert-butylphenol), and 4,4'-thiobis(6-tert-butyl-3-methylphenol).

[0064] In a specific embodiment of the present invention, the light stabilizer includes at least one selected from 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, light stabilizer 944, bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate, polysuccinate (4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol) ester and 3,5-di-tert-butyl-4-hydroxybenzoate hexadecyl ester.

[0065] In a specific embodiment of the present invention, the silane coupling agent includes at least one of γ-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, triacetoxyvinylsilane, vinyltri(2-methoxyethoxy)silane, and γ-(methacryloyloxy)propyltrimethoxysilane.

[0066] Another aspect of the present invention provides a method for preparing any of the above-mentioned EPE films, comprising the following steps: co-extruding and casting according to the composition of the first EVA layer, the POE layer and the second EVA layer to obtain an EPE encapsulation film.

[0067] Another aspect of the present invention provides a photovoltaic module comprising any of the above-mentioned EPE films.

[0068] The material information used in the following specific embodiments of the present invention may be as follows, but is not limited thereto:

[0069] EVA resin: Sirbon V2825;

[0070] POE resin: Dow PV8669.

[0071] Example 1

[0072] This embodiment provides an EPE film, comprising a first EVA layer, a POE layer, and a second EVA layer arranged sequentially. The thickness of both the first and second EVA layers is 125 μm, and the thickness of the POE layer is 140 μm.

[0073] The first and second EVA layers comprise the following components by weight: 100 parts EVA resin, 1 part tert-butyl peroxide-2-ethylhexyl carbonate, 0.5 parts ethylene glycol dimethacrylate, 0.5 parts tri(nonylphenyl) phosphite, 0.6 parts 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1 part γ-glycidyl etheroxypropyltrimethoxysilane, and 0.2 parts decyl glucoside.

[0074] The POE layer comprises the following components by weight: 100 parts POE resin, 1 part tert-butyl peroxide-3,5,5-trimethylhexanoate, 0.6 parts trimethylolpropane triacrylate, 0.3 parts 2,6-di-tert-butyl-p-cresol, 0.6 parts light stabilizer 944, and 1 part vinyltriethoxysilane.

[0075] The method for preparing the EPE film in this embodiment includes the following steps: after premixing the ingredients according to the composition of the first EVA layer, the POE layer and the second EVA layer, the film is obtained by plasticizing extrusion, stretching, traction and winding at 80°C through a casting extruder.

[0076] Example 2

[0077] This embodiment refers to the EPE film and its preparation method in Example 1, the only difference being that the composition of the first EVA layer and the second EVA layer are different.

[0078] The first and second EVA layers of this embodiment comprise the following components by weight: 100 parts EVA resin, 1 part tert-butyl peroxide-2-ethylhexyl carbonate, 0.5 parts ethylene glycol dimethacrylate, 0.5 parts tri(nonylphenyl) phosphite, 0.6 parts 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1.5 parts γ-glycidyl etheroxypropyltrimethoxysilane, and 1 part decyl glucoside.

[0079] Example 3

[0080] This embodiment refers to the EPE film and its preparation method in Example 1, the only difference being that the composition of the first EVA layer and the second EVA layer are different.

[0081] The first and second EVA layers of this embodiment comprise the following components by weight: 100 parts EVA resin, 1 part tert-butyl peroxide-2-ethylhexyl carbonate, 0.5 parts ethylene glycol dimethacrylate, 0.5 parts tri(nonylphenyl) phosphite, 0.6 parts 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 0.3 parts γ-glycidyl etheroxypropyltrimethoxysilane, and 0.005 parts decyl glucoside.

[0082] Example 4

[0083] This embodiment refers to the EPE film and its preparation method in Example 1, the only difference being that the composition of the first EVA layer and the second EVA layer are different.

[0084] The first and second EVA layers of this embodiment comprise the following components by weight: 100 parts EVA resin, 1 part tert-butyl peroxide-2-ethylhexyl carbonate, 0.5 parts ethylene glycol dimethacrylate, 0.5 parts tri(nonylphenyl) phosphite, 0.6 parts 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1 part γ-glycidyl etheroxypropyltrimethoxysilane, and 0.05 parts decyl glucoside.

[0085] Example 5

[0086] This embodiment refers to the EPE film and its preparation method in Example 1, the only difference being that the composition of the first EVA layer and the second EVA layer are different.

[0087] The first and second EVA layers of this embodiment comprise the following components by weight: 100 parts EVA resin, 1 part tert-butyl peroxide-2-ethylhexyl carbonate, 0.5 parts ethylene glycol dimethacrylate, 0.5 parts tri(nonylphenyl) phosphite, 0.6 parts 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1 part γ-glycidyl etheroxypropyltrimethoxysilane, and 0.6 parts decyl glucoside.

[0088] Example 6

[0089] This embodiment refers to the EPE film and its preparation method in Example 1, the only difference being that the composition of the first EVA layer and the second EVA layer are different.

[0090] The first and second EVA layers of this embodiment comprise the following components by weight: 100 parts EVA resin, 1 part tert-butyl peroxide-2-ethylhexyl carbonate, 0.5 parts ethylene glycol dimethacrylate, 0.5 parts tri(nonylphenyl) phosphite, 0.6 parts 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1 part γ-glycidyl etheroxypropyltrimethoxysilane, and 1 part decyl glucoside.

[0091] Example 7 group

[0092] The examples in this group refer to the EPE film and its preparation method in Example 1, the only difference being that the types of surfactants in the first EVA layer and the second EVA layer are different.

[0093] In Example 7a, decyl glucoside was replaced with an equal weight of hexyl glucoside;

[0094] In Example 7b, decyl glucoside was replaced with an equal weight of dodecyl glucoside;

[0095] In Example 7c, decyl glucoside was replaced with an equal weight of octadecyl glucoside;

[0096] In Example 7d, decyl glucoside was replaced with an equal weight of hexyldimethyl betaine.

[0097] In Example 7e, decyl glucoside was replaced with an equal weight of dodecyl dimethyl betaine;

[0098] In Example 7f, decyl glucoside was replaced with an equal weight of hexadecyl dimethyl betaine;

[0099] In Example 7g, decyl glucoside was replaced by an equal weight of docosyldimethyl betaine.

[0100] In Example 7h, decyl glucoside was replaced with an equal weight of sodium hexyl sulfonate;

[0101] In Example 7i, sodium dodecyl sulfonate was used to replace decyl glucoside by an equal weight;

[0102] In Example 7j, sodium hexadecyl sulfonate of equal weight was used to replace decyl glucoside;

[0103] In Example 7k, sodium tetradecyl sulfonate of equal weight was used to replace decyl glucoside.

[0104] Hexyl dimethyl betaine can be prepared by reacting N,N-dimethylhexylamine with chloroacetic acid, but is not limited thereto; docosyl dimethyl betaine can be prepared by reacting dimethyl behenamine with chloroacetic acid, but is not limited thereto; sodium tetradecyl sulfonate can be prepared by reacting 1-bromotetradecane with sodium sulfite, but is not limited thereto.

[0105] Example 8

[0106] This embodiment refers to the EPE film and its preparation method in Example 1, the only difference being that the thicknesses of the first EVA layer, the POE layer and the second EVA layer are different.

[0107] In this embodiment, the thickness of both the first EVA layer and the second EVA layer is 190 μm, and the thickness of the POE layer is 80 μm.

[0108] Comparative Example 1

[0109] Comparative Example 1 refers to the EPE film and its preparation method in Example 1, the difference being that the types of surfactants in the first EVA layer and the second EVA layer are different.

[0110] In Comparative Example 1, decyl glucoside was replaced with an equal weight of butyl glucoside.

[0111] Comparative Example 2

[0112] Comparative Example 2 refers to the EPE film and its preparation method of Example 1, the difference being that the types of surfactants in the first EVA layer and the second EVA layer are different.

[0113] In Comparative Example 2, decyl glucoside was replaced with an equal weight of butyl dimethyl betaine.

[0114] Butyl dimethyl betaine can be prepared by reacting n-butyl dimethylamine with chloroacetic acid, but is not limited to this method.

[0115] Comparative Example 3

[0116] Comparative Example 3 refers to the EPE film and its preparation method of Example 1, the difference being that the types of surfactants in the first EVA layer and the second EVA layer are different.

[0117] In Comparative Example 3, sodium butane sulfonate was used to replace decyl glucoside by an equal weight.

[0118] Comparative Example 4

[0119] Comparative Example 4 refers to the EPE film and its preparation method of Example 1, the difference being that the composition of the first EVA layer and the second EVA layer are different.

[0120] The first and second EVA layers of Comparative Example 4 comprise the following components by weight: 100 parts EVA resin, 1 part tert-butyl peroxide-2-ethylhexyl carbonate, 0.5 parts ethylene glycol dimethacrylate, 0.5 parts tri(nonylphenyl) phosphite, 0.6 parts 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1 part γ-glycidoxypropyltrimethoxysilane, and 0.002 parts decyl glucoside.

[0121] Comparative Example 5

[0122] Comparative Example 5 refers to the EPE film and its preparation method of Example 1, the difference being that the composition of the first EVA layer and the second EVA layer are different.

[0123] The first and second EVA layers of Comparative Example 5 comprise the following components by weight: 100 parts EVA resin, 1 part tert-butyl peroxide-2-ethylhexyl carbonate, 0.5 parts ethylene glycol dimethacrylate, 0.5 parts tri(nonylphenyl) phosphite, 0.6 parts 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 1 part γ-glycidoxypropyltrimethoxysilane, and 1.2 parts decyl glucoside.

[0124] Comparative Example 6

[0125] Comparative Example 6 refers to the EPE film and its preparation method of Example 1, the difference being that the composition of the first EVA layer and the second EVA layer are different.

[0126] No surfactant was added to the first and second EVA layers in Comparative Example 6.

[0127] Experimental Example

[0128] To compare and illustrate the performance differences of different EPE films, the EPE films prepared in different examples and comparative examples were tested as follows. The test methods are as follows, and the test results are shown in Table 1.

[0129] Photovoltaic module samples were fabricated using EPE films from different embodiments and comparative examples. The initial module power and the power of the photovoltaic modules after PID-192h were tested according to IEC62804-1:2015, and the degradation rate was calculated based on these two data points. The appearance changes of the photovoltaic modules after PID-192h were also recorded. The fabrication of the photovoltaic modules included laminating double-glass modules in the following order: upper glass, upper EPE film, solar cells, lower EPE film, and lower glass. 210R size TOPCon solar cells were used, resulting in a 48mm module. The initial power of a conventional TOPCon module is 455W.

[0130] Table 1 Test results for different EPE films

[0131]

[0132]

[0133] The test results above show that by adding surfactants with long-chain hydrophobic and hydrophilic structures to the EVA layer, the present invention can reduce the cost of the film while ensuring its adhesive performance. It can prevent the corresponding photovoltaic module from delamination in the PID-192h test and reduce the module power attenuation by <2% even with a low POE layer thickness (≤140μm).

[0134] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An EPE adhesive film, characterized in that, The EPE adhesive film comprises a first EVA layer, a POE layer and a second EVA layer arranged in sequence. The first EVA layer and the second EVA layer each independently comprise the following components by weight fraction: EVA resin 100 parts, crosslinking agent 0.5-1.5 parts, auxiliary crosslinking agent 0.1-1 part, antioxidant 0.1-0.5 part, light stabilizer 0.1-1 part, silane coupling agent 0.3-1.5 parts and surfactant 0.005-1 part. The POE layer comprises the following components by weight fraction: POE resin 100 parts, crosslinking agent 0.5-1.5 parts, auxiliary crosslinking agent 0.1-1 part, antioxidant 0.1-0.5 part, light stabilizer 0.1-1 part and silane coupling agent 0.3-1.5 parts. The surfactant comprises at least one of alkyl glycoside surfactant, alkyl betaine surfactant and sodium alkyl sulfonate surfactant. The alkyl glycoside surfactant is an alkyl glycoside with a carbon chain length of C6-C18. The alkyl betaine surfactant has the following general structure: ； wherein R1 is a linear alkyl group with a carbon atom number of 6-22, and R2 is an alkylene group with a carbon atom number of 1-5. The sodium alkyl sulfonate surfactant is sodium alkyl sulfonate with a carbon chain length of C6-C24.

2. The EPE adhesive film according to claim 1, characterized in that, The alkyl glycoside comprises at least one of hexyl glucoside, decyl glucoside, dodecyl glucoside and octadecyl glucoside.

3. The EPE adhesive film according to claim 1, wherein The alkyl betaine surfactant comprises hexyldimethyl betaine, dodecyldimethyl betaine, tetradecyldimethyl betaine, hexadecyldimethyl betaine, octadecyldimethyl betaine and docosyl dimethyl betaine.

4. The EPE adhesive film of claim 1, wherein The sodium alkyl sulfonate surfactant comprises at least one of hexyl sodium sulfonate, dodecyl sodium sulfonate, tetradecyl sodium sulfonate, hexadecyl sodium sulfonate and tetradecyl sodium sulfonate.

5. The EPE adhesive film of claim 1, wherein In the first EVA layer and the second EVA layer, the mass ratio of the silane coupling agent to the surfactant is 1:(0.05-0.6).

6. The EPE adhesive film of claim 1, wherein The thickness ratio of the first EVA layer, the POE layer and the second EVA layer is (1-2):1:(1-2).

7. The EPE adhesive film of claim 1, wherein The thickness of the first EVA layer and the second EVA layer is 250-380 μm, and the thickness of the POE layer is 80-140 μm.

8. The EPE adhesive film of claim 1, wherein The silane coupling agent comprises at least one of γ-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, triacetoxyvinylsilane, vinyltris(2-methoxyethoxy)silane and γ-(methacryloyloxy)propyltrimethoxysilane.

9. A method for producing an EPE film, characterized by, The method comprises the following steps: preparing the component ingredients of the first EVA layer, the POE layer and the second EVA layer of the EPE adhesive film according to any one of claims 1-8, and performing co-extrusion casting to obtain the EPE adhesive film.

10. A photovoltaic module characterized by, The method comprises the EPE adhesive film according to any one of claims 1-8.

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