Composite integrated membrane as well as preparation method and application thereof

Abstract

The invention relates to the technical field of photovoltaic modules, in particular to a composite integrated film and a preparation method and application thereof. The composite integrated film comprises a first packaging adhesive film layer and an activated fluorine-containing film layer which are stacked. Wherein the water contact angle a1 of one side, close to the first packaging adhesive film layer, of the activated fluorine-containing film layer is 30-70 degrees. According to the invention, by controlling the water contact angle of the fluorine-containing film layer, the light transmittance of the adhesive film can be ensured, and the adhesive force between the packaging adhesive film layer and the fluorine-containing film layer is remarkably enhanced, so that the transparent fluorine-containing film and the packaging adhesive film are integrally compounded.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic modules, and in particular to a composite integrated film and a preparation method and application thereof. Background Art

[0002] Conventional photovoltaic modules generally use photovoltaic glass as the front layer, which allows sunlight to penetrate the cell surface and protects the modules. However, photovoltaic glass also has some obvious disadvantages as the front layer, such as heavy weight, high module transportation cost, and easy breakage.

[0003] At present, transparent fluorine-containing films such as ETFE, PTFE, TPT (PVF-PET-PVF composite film) are introduced in flexible components to replace photovoltaic glass as the front layer, ensuring the reliability of the components while achieving lightweight and portability. The above-mentioned fluorine-containing films have the advantages of high light transmittance, high anti-fouling, high flame retardancy and recyclability, and their application in the photovoltaic field has gradually developed. However, another characteristic of the above-mentioned fluorine-containing films is that they are extremely hydrophobic, have poor wettability, and can hardly bond to other interfaces. Therefore, at this stage, it is necessary to use an adhesive layer to bond the fluorine-containing film and the encapsulation film. However, in fact, due to the extreme hydrophobicity of the fluorine-containing film, even if adhesive is used for bonding, there is still room for further improvement in the bonding strength between the fluorine-containing film and the encapsulation film.

[0004] In view of this, in the prior art, CN112622381A discloses a fluorine-containing polymer composite film, including a fluorine-containing weather-resistant film layer, a glue layer and an adhesive film layer, wherein the adhesive layer includes a polyethylene adhesive film, a POE adhesive film, and an EVA adhesive film, and in order to improve the bonding force between the fluorine-containing weather-resistant film layer and the adhesive film layer, glue is used to bond the two. However, this will obviously reduce the refractive index and light transmittance of the composite film to a large extent, and the operation process is cumbersome and not conducive to industrial production.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] In view of the problems existing in the prior art, the purpose of the present invention is to provide a composite integrated film and a preparation method and application thereof, which can be used in lightweight components or thin film components. By realizing the integrated composite of a transparent fluorine-containing film and a packaging film, the component manufacturer's component preparation process can be reduced and production efficiency can be improved.

[0007] Based on this, the specific technical solutions of the present invention are as follows: In a first aspect, the present invention first provides a composite integrated film, which includes a stacked first packaging film layer and an activated fluorine-containing film layer; wherein the water contact angle a1 of the activated fluorine-containing film layer on the side close to the first packaging film layer is 30°~70°.

[0008] The present invention finds that by controlling the water contact angle a1 of the activated fluorine-containing film layer close to the first packaging film layer to be within the above range, the bonding force between the packaging film layer and the fluorine-containing film layer can be significantly enhanced, thereby facilitating the integrated composite of the transparent fluorine-containing film and the packaging film.

[0009] In the present invention, a1 can be any value among 30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, and 70°, or a numerical range in which any two of the above values ​​are endpoints.

[0010] Preferably, the water contact angle a2 of the first encapsulation film layer close to the activated fluorine-containing film layer is 45° to 80°.

[0011] In the present invention, a2 can be any value among 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, or a numerical range in which any two of the above values ​​are endpoints.

[0012] Preferably, the water contact angle |a1-a2| between the contact surface of the fluorine-containing thin film layer after the activation treatment and the first encapsulation film layer is controlled to be 0-50°.

[0013] The present invention finds that controlling the water contact angle between the contact surface of the activated fluorine-containing film layer and the first packaging film layer to be between 0 and 50 degrees can significantly improve the adhesion of the two interfaces by increasing the covalent bonds and intermolecular forces of the two interfaces, thereby facilitating the integrated composite of the transparent fluorine-containing film and the packaging film.

[0014] The water contact angles in the present invention are all water contact angles tested according to the testing method in the examples.

[0015] Preferably, the roughness Ra of the activated fluorine-containing film layer on the side close to the first packaging film layer is 0.01-0.05 μm, and the roughness Ra' of the first packaging film layer on the side close to the fluorine-containing film layer is 0.01-0.10 μm; Preferably, |Ra-Ra'|=0~0.10μm.

[0016] The present invention finds that by controlling the roughness difference between the two contact interfaces of the fluorine-containing film layer and the first encapsulation film layer after the activation treatment to 0-0.10 μm, the physical fit between the two interfaces can be improved, thereby further improving the adhesion of the two interfaces. If the roughness is too large, the light transmittance of the composite integrated film may be reduced or the haze may be increased, ultimately affecting the efficiency of the photovoltaic module.

[0017] Preferably, the activation treatment comprises plasma treatment.

[0018] More preferably, the plasma treatment includes air ionization or introducing external gas for ionization; the external gas includes one or more of argon, nitrogen and oxygen; the ionization condition is: voltage 10~5000V.

[0019] Further preferably, the voltage may be 20-3000V; specifically, it may be any value among 20V, 50V, 100V, 200V, 500V, 1000V, 1500V, 2000V, 2500V, 3000V, or a numerical range in which any two of the above values ​​are endpoints.

[0020] Preferably, the thickness of the composite integrated film is 0.15~4.00mm; specifically, it can be any value among 0.15mm, 0.20mm, 0.25mm, 0.30mm, 0.40mm, 0.50mm, 0.60mm, 0.70mm, 0.80mm, 0.90mm, 1.00mm, 1.50mm, 2.00mm, 2.50mm, 3.00mm, 3.50mm, 4.00mm, or a numerical range with any two of the above values ​​as endpoints.

[0021] Preferably, the thickness of the first packaging film layer is 0.10-0.95 mm; specifically, it can be any value among 0.10 mm, 0.20 mm, 0.30 mm, 0.40 mm, 0.50 mm, 0.60 mm, 0.70 mm, 0.80 mm, 0.90 mm and 0.95 mm, or a numerical range with any two of the above values ​​as endpoints.

[0022] Preferably, the thickness of the fluorine-containing film layer after activation treatment is 0.05~3.00mm; specifically, it can be any value among 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.10mm, 0.11mm, 0.12mm, 0.13mm, 0.14mm, 0.15mm, 0.16mm, 0.17mm, 0.18mm, 0.19mm, 0.20mm, 0.30mm, 0.40mm, 0.50mm, 0.60mm, 0.70mm, 0.80mm, 0.90mm, 1.00mm, 1.50mm, 2.00mm, 2.50mm, 3.00mm, or a numerical range with any two of the above values ​​as endpoints.

[0023] In the present invention, the number of layers of the first encapsulation film layer may be one layer or multiple layers, which is not specifically limited herein.

[0024] Preferably, the material of the first encapsulation film layer includes at least one of EVA (ethylene-vinyl acetate copolymer), POE (ethylene-alpha olefin copolymer), PE (polyethylene), PVB (polyvinyl butyral), PMMA (polymethyl methacrylate), PC (polycarbonate), POP (polymer polyol), EAA (ethylene-acrylic acid copolymer), EMA (ethylene-methacrylate copolymer), EBA (ethylene-butyl acrylate copolymer), EMH (ethylene-acrylate-maleic anhydride copolymer), ionomer, polysiloxane, EPDM rubber, ethylene-ethyl acrylate copolymer and TPU (thermoplastic polyurethane), more preferably at least one of EVA, POE and PVB.

[0025] Preferably, the fluorine-containing film layer material includes at least one of ETFE (ethylene-tetrafluoroethylene copolymer), PTFE (polytetrafluoroethylene), PVDF (polyvinylidene fluoride), and PVF (polyvinyl fluoride).

[0026] Preferably, another encapsulation film layer is stacked on a side of the first encapsulation film layer away from the fluorine-containing thin film layer; and the number of layers of the another encapsulation film layer is more than one.

[0027] In the specific implementation process, those skilled in the art may select the material of the first encapsulation film layer in the composite integrated film to be the same as or different from the material type of other encapsulation film layers according to actual conditions, which is not limited here.

[0028] Preferably, the material of the first encapsulation film layer is the same as or different from the material of the other encapsulation film layers and includes at least one of EVA, POE, PE, PVB, PMMA, PC, POP, EAA, EMA, EBA, EMH and TPU.

[0029] Further preferably, the material of the first encapsulation film layer and the material of the other encapsulation film layers include at least one of POE, EVA and PVB.

[0030] Preferably, an outer film is further provided on a side of the fluorine-containing thin film layer away from the first encapsulation film layer; and the number of layers of the outer film is more than one.

[0031] More preferably, the material of the outer film includes at least one of ETFE, PTFE, PVDF, PVF, PET (polyethylene terephthalate), and PI (polyimide).

[0032] Further preferably, the material of the outer film includes a composite film of at least one of ETFE, PTFE, PVDF, PVF and PET, and the PET is arranged close to the fluorine-containing film.

[0033] In the present invention, the composition of the encapsulation film includes 100 parts of polymer resin, 0.01-1.5 parts by weight of a crosslinking agent, 0.5-10 parts by weight of an auxiliary crosslinking agent, 0.1-5 parts by weight of a tackifier and 0.1-1.0 parts by weight of a light stabilizer.

[0034] Preferably, the polymer resin includes at least one of EVA, POE, PE, PVB, PMMA, PC, POP, EAA, EMA, EBA, EMH, ionomer, polysiloxane, EPDM rubber, ethylene-ethyl acrylate copolymer and TPU.

[0035] Preferably, the crosslinking agent is a peroxide crosslinking agent, including at least one of o-, o-tert-butyl-o-(2-ethylhexyl)-mono-peroxycarbonate, n-butyl 4,4-di(tert-butylperoxy)valerate, 2,5-dimethyl-2,5-bis(benzoylperoxy)-hexane, and 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane.

[0036] Preferably, the auxiliary crosslinking agent is a multifunctional acrylate or methacrylate auxiliary crosslinking agent, including at least one of triallyl isocyanurate, triallyl cyanurate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate and pentaerythritol triacrylate.

[0037] Preferably, the adhesion promoter includes at least one of γ-glycidyloxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltri(β-methoxyethoxy)silane, aminopropyltrimethoxysilane, aminopropyltriethoxysilane, aminopropyltriisopropoxysilane and γ-glycidyloxypropyltrimethoxysilane.

[0038] Preferably, the light stabilizer includes at least one of bis-2,2,6,6-tetramethylpiperidinol sebacate, bis(2,2,6,6-tetramethyl-4-piperidinyl) sebacate, 3,5-di-tert-butyl-4-hydroxy-benzoic acid hexadecyl ester, poly(4-hydroxy-2,2,6,6-tetramethyl-1-piperidinethanol) succinate, tris(1,2,2,6,6-pentamethylpiperidinyl) phosphite, and bis(1,2,2,6,6-pentamethyl-4-piperidinyl) sebacate.

[0039] As a preferred embodiment of the present invention, the material of the fluorine-containing film layer is ETFE, and the material of the first packaging film layer includes EVA.

[0040] In a second aspect, the present invention further provides a method for preparing the composite integrated membrane, comprising: S1: activating the surface of the fluorine-containing thin film layer close to the first packaging film to obtain an activated fluorine-containing thin film layer; S2: casting or laminating the melted material of the first packaging film onto the surface of the activated fluorine-containing film layer to obtain a composite film; S3: performing a composite treatment on the composite film to obtain the composite integrated film; wherein the surface hardness of the first packaging film is 45-80 HA (Shore hardness).

[0041] Alternatively, the method for preparing the composite integrated membrane comprises: S1': activating the surface of the fluorine-containing thin film layer close to the first packaging film to obtain an activated fluorine-containing thin film layer; S2': laminating and pressing the first packaging film and the fluorine-containing film layer by layer to obtain a composite film; S3': subjecting the composite film to composite treatment to obtain the composite integrated film; wherein the surface hardness of the first packaging film is 45-80HA.

[0042] More preferably, the surface hardness of the first packaging film is 45-80HA, for example, it can be any value among 45HA, 50HA, 55HA, 60HA, 65HA, 70HA, 75HA and 80HA, or a numerical range with any two of the above values ​​as endpoints.

[0043] Preferably, the composite treatment comprises baking treatment or electron beam treatment; more preferably, electron beam treatment.

[0044] Further preferably, the baking treatment comprises baking the composite film at 80° C. to 100° C.; preferably, the baking time is 3 to 10 minutes.

[0045] Further preferably, the electron beam treatment includes irradiating the composite film with an electron beam having an irradiation amount of 2 to 50 KGY.

[0046] Preferably, the fluorine-containing film layer can be obtained by at least one of extrusion, film blowing, molding, rolling, injection molding, casting, and stretching, or by coating and curing the coating to form a film.

[0047] Preferably, an outer film is further provided on the side of the fluorine-containing film layer away from the first encapsulation film layer, and the fluorine-containing film layer is obtained by coating a coating on the outer film and curing the coating to form a film.

[0048] Further preferably, the method for preparing the composite integrated film further comprises S4: casting, laminating and pressing at least one other encapsulating film layer on the surface of the first encapsulating film.

[0049] In a third aspect, the present invention provides a photovoltaic module comprising the composite integrated film.

[0050] Preferably, the structure of the photovoltaic module includes the composite integrated film, the battery cell, the back side packaging film and the back plate material laminated in sequence.

[0051] Preferably, the light transmittance of the composite integrated film is ≥85%.

[0052] Based on the above technical solution, the beneficial effects of the present invention are: The present invention controls the water contact angle of the side of the fluorine-containing film layer that is attached to the encapsulation corneal layer, thereby ensuring the light transmittance of the film and significantly enhancing the bonding force between the encapsulation film layer and the fluorine-containing film layer, thereby achieving the integrated composite of the transparent fluorine-containing film and the encapsulation film. At the same time, the introduction of the composite integrated film into the photovoltaic module can achieve lightweight modules, reduce module transportation costs, reduce the number of module preparation processes by module manufacturers, and improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0054] Figure 1 Schematic diagram of the multilayer structure of the cross section of the composite integrated membrane prepared in Example 1 provided by the present invention; Figure 2 is a schematic diagram of a method for preparing a composite integrated membrane prepared in Example 1 provided by the present invention; Figure 3 Schematic diagram of the multilayer structure of the cross section of the composite integrated membrane prepared in Example 2 provided by the present invention; Reference numerals: 1: ETFE film; 2: first packaging film; 3: second packaging film. DETAILED DESCRIPTION

[0055] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0056] Unless otherwise specified, the various raw materials used in the examples and comparative examples are commercially available conventional raw materials, and the technical means used are conventional means well known to those skilled in the art.

[0057] Example 1 This embodiment provides a composite integrated film, the schematic diagram of the multi-layer structure of which is shown in FIG. Figure 1 The schematic diagram of its preparation method is shown in Figure 2 , and its preparation method comprises the following steps: S1: Plasma treatment is performed on the surface of ETFE (manufacturer Shanghai Weitelang, thickness 100um) in contact with the first packaging film EVA, wherein the plasma treatment specifically includes: ionizing gas air, voltage 200V; the water contact angle of the activated ETFE close to the first packaging film is 45°.

[0058] S2: Casting the first encapsulating film EVA onto the activated ETFE surface to obtain a composite film.

[0059] S3: subjecting the composite film to composite treatment, wherein the composite treatment comprises baking at 90° C. for 5 minutes.

[0060] The first encapsulation adhesive film EVA includes: 100 parts of EVA polymer resin, 0.1 parts by mass of o-, o-tert-butyl-o-(2-ethylhexyl)-mono-peroxycarbonate crosslinking agent, 0.6 parts by mass of triallyl cyanurate crosslinking aid, 0.5 parts by mass of aminopropyl triisopropoxy silane adhesion promoter and 0.2 parts by mass of bis-2,2,6,6-tetramethylpiperidinol sebacate light stabilizer.

[0061] The surface hardness of the first packaging film EVA is 65HA.

[0062] The thickness of the composite integrated film is 0.35 mm, wherein the thickness of the activated fluorine-containing thin film layer is 0.10 mm, and the thickness of the first packaging film is 0.25 mm.

[0063] Example 2 This embodiment provides a composite integrated film, the schematic diagram of the multi-layer structure of which is shown in FIG. Figure 3 The difference between the preparation method and the embodiment 1 is that after low-temperature baking in S3, a second packaging film POE is further bonded to the surface of the first packaging film.

[0064] The second encapsulation film POE includes: 100 parts of POE polymer resin, 0.3 parts by mass of o-tert-butyl-o-(2-ethylhexyl)-mono-peroxycarbonate crosslinker, 0.5 parts by mass of triallyl cyanurate crosslinking aid, 0.6 parts by mass of vinyl triethoxysilane adhesion promoter and 0.1 parts by mass of bis-2,2,6,6-tetramethylpiperidinol sebacate light stabilizer.

[0065] The thickness of the composite integrated film is 0.50 mm, wherein the thickness of the activated fluorine-containing film layer is 0.10 mm, the thickness of the first packaging film is 0.25 mm, and the thickness of the laminated second packaging film is 0.15 mm.

[0066] Example 3 This embodiment provides a composite integrated membrane, and the preparation method thereof comprises the following steps: S1: Plasma treatment is performed on the surface of ETFE (manufacturer Shanghai Weitelang, thickness 100um) close to the first packaging film EVA, and the plasma treatment specifically includes: ionizing gas air, voltage 200V; the water contact angle of the activated ETFE close to the first packaging film is 45°.

[0067] S2: coating the first packaging film EVA on the surface of the activated ETFE, and then performing a composite treatment, wherein the composite treatment includes baking at 90° C. for 5 minutes.

[0068] S3: Casting the second packaging film POE onto the surface of the first packaging film EVA to obtain a composite integrated film; the surface hardness of the first packaging film is 65HA.

[0069] The formula of the first encapsulation film is the same as the formula of the first encapsulation film EVA in Example 1, and the formula of the second encapsulation film is the same as the formula of the second encapsulation film POE in Example 2.

[0070] The thickness of the composite integrated film is 0.50 mm, wherein the thickness of the activated fluorine-containing film layer is 0.10 mm, the thickness of the first packaging film is 0.25 mm, and the thickness of the second packaging film is 0.15 mm.

[0071] Example 4 This embodiment provides a composite integrated film, and the differences between its preparation method and that of Embodiment 1 include: in S3, the baking temperature is 80°C.

[0072] Example 5 This embodiment provides a composite integrated film, and the difference between its preparation method and that of embodiment 1 includes: in S3, the composite treatment is electron beam treatment, specifically including: irradiation amount of 10KGY.

[0073] Example 6 This embodiment provides a composite integrated film, and the difference between its preparation method and that of embodiment 1 includes: in S3, the composite treatment is electron beam treatment, specifically including: irradiation amount of 20KGY.

[0074] Example 7 This embodiment provides a composite integrated film, and the difference between its preparation method and that of embodiment 1 is that EVA is replaced by POE. The formula of the POE film is the same as the formula of the second encapsulation film in embodiment 2.

[0075] Example 8 This embodiment provides a composite integrated film, and the difference between its preparation method and that of embodiment 1 is that EVA is replaced by POE. The formula of the POE is 100 parts of POE polymer resin, 0.1 parts by mass of 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, 0.5 parts by mass of triallyl cyanurate crosslinking agent, 0.5 parts by mass of vinyl triethoxysilane tackifier, and 0.3 parts by mass of 3,5-di-tert-butyl-4-hydroxy-benzoic acid hexadecyl ester light stabilizer.

[0076] Example 9 This embodiment provides a composite integrated membrane, and the difference between its preparation method and that of embodiment 1 includes: replacing the ETFE layer with a PTFE layer (manufacturer Shenzhen Chenyonghong, thickness 100um), and the water contact angle of the activated PTFE close to the first packaging film is 45°.

[0077] Example 10 This embodiment provides a composite integrated film, and the difference between its preparation method and that of Embodiment 1 includes: replacing the ETFE layer with TPT (PVF layer + PET layer + PVF layer) (manufacturer DuPont, thickness 100um), and the water contact angle of the activated TPT close to the first packaging film side is 45°.

[0078] Embodiment 11 This embodiment provides a composite integrated film, and the difference between its preparation method and that of embodiment 1 is that: the plasma treatment specifically includes: voltage 60V, gas air; the water contact angle of the activated ETFE close to the first packaging film is 70°.

[0079] Example 12 This embodiment provides a composite integrated film, and the difference between its preparation method and that of embodiment 1 is as follows: the plasma treatment specifically includes: voltage 3000V, gas argon; the water contact angle of the activated ETFE close to the first packaging film is 30°.

[0080] Example 13 This embodiment provides a composite integrated film, and the difference between its preparation method and that of Embodiment 1 includes: the surface hardness of the first packaging film is 45HA.

[0081] Embodiment 14 This embodiment provides a composite integrated film, and the differences between its preparation method and that of embodiment 1 include: in S2, the first packaging film is cast and then bonded to the activated ETFE surface to obtain a composite film; the surface hardness of the first packaging film is 80HA.

[0082] Embodiment 15 This comparative example first provides a composite integrated membrane, and the difference between its preparation method and that of Example 1 includes: no S3 is contained, that is, the composite membrane is not subjected to composite treatment.

[0083] Comparative Example 1 This comparative example first provides a composite integrated film, the preparation method of which is different from that of Example 1 in that: ETFE is not activated, and the water contact angle of the ETFE close to the first packaging film is 110°.

[0084] Comparative Example 2 This comparative example first provides a composite integrated film, and the differences between its preparation method and Example 1 include: the plasma treatment specifically includes: voltage 5V, gas air; the water contact angle of the activated ETFE close to the first packaging film is 80°.

[0085] Comparative Example 3 This comparative example first provides a composite integrated film, and the difference between its preparation method and Example 1 is that the plasma treatment specifically includes: voltage 8000V, gas air; the water contact angle of the activated ETFE close to the first packaging film is 25°; EVA is replaced by PE. The formula of the PE is 100 parts of PE polymer resin, 0.1 parts by mass of o-, o-tert-butyl-o-(2-ethylhexyl)-mono-peroxycarbonate crosslinker, 0.6 parts by mass of triallyl cyanurate crosslinking agent, 0.5 parts by mass of aminopropyl triisopropoxy silane tackifier and 0.2 parts by mass of sebacic acid bis-2,2,6,6-tetramethylpiperidinol ester light stabilizer.

[0086] Test example The present invention further tests the bonding force between the first packaging adhesive film and the fluorine-containing film in the composite integrated film prepared in the above-mentioned embodiment and comparative example, as well as the light transmittance of the composite integrated film.

[0087] Among them, water contact angle detection method: test equipment-optical contact angle and interfacial tension meter; model-SL150E; brand-American Kono; test parameters-test type (sessile drop method), test rate (0.5000 Frame / s), droplet volume (2uL), data processing (circle fitting); Roughness detection method: Scanning electron microscope (SEM, Phenom Prox) test Ra value; Test method for mechanical properties (tensile strength): GB / T 13542.2-2021; Adhesion testing method: refer to the peel strength test method between EVA and glass in GB / T 29848-2018; The test method for light transmittance is GB / T2410-2008.

[0088] The results are shown in Table 1.

[0089] Table 1

[0090] According to the results of the embodiment and comparative examples 1 to 3, and embodiment 11 to 12, it can be known that by controlling the water contact angle a1 of the side of the fluorine-containing film layer close to the first encapsulation film layer after the activation treatment, the bonding force between the encapsulation film layer and the fluorine-containing film layer can be significantly enhanced, which is conducive to realizing the integrated composite of the transparent fluorine-containing film and the encapsulation film. According to the experimental results of embodiment 1 to embodiment 3, embodiment 9 to embodiment 10, it can be known that under the preparation method described in the present invention, different numbers of layers of encapsulation films (such as one or two layers) and different fluorine-containing films within the scope of the present invention (such as ETFE, PTFE or TPT, etc.) can be used to obtain higher bonding force and better light transmittance, so the preparation method of the present invention is universal for different fluorine-containing films. According to the experimental results of embodiment 1 and embodiment 7 to embodiment 8, although different encapsulation film materials will affect the bonding force of the two interfaces in the composite integrated film to a certain extent, the effect is still significantly better than the comparative example, so the preparation method of the present invention is actually still universal for different encapsulation film materials. According to the comparison between Example 1 and Example 13 to Example 14, it can be seen that the surface hardness of the first packaging film will have a greater impact on the adhesion of the two interfaces, and casting the first packaging film onto the surface of the activated fluorine-containing thin film layer helps to reduce the surface hardness of the packaging film layer, thereby achieving integrated composite of the transparent fluorine-containing thin film and the packaging film.

[0091] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A composite integrated membrane, characterized in that: It comprises a stacked first packaging film layer and an activated fluorine-containing film layer; wherein the water contact angle a1 of the activated fluorine-containing film layer on a side close to the first packaging film layer is 30°-70°.

2. The composite integrated membrane according to claim 1, characterized in that: The water contact angle a2 of the first encapsulation film layer close to the fluorine-containing film layer is 45° to 80°; Preferably, |a1-a2|=0~50°.

3. The composite integrated membrane according to claim 1, characterized in that: The roughness Ra of the activated fluorine-containing film layer on the side close to the first packaging film layer is 0.01-0.05 μm, and the roughness Ra' of the first packaging film layer on the side close to the fluorine-containing film layer is 0.01-0.10 μm; And / or, the absolute value of the difference in roughness between the two |Ra-Ra'|=0~0.10μm.

4. The composite integrated membrane according to claim 1, characterized in that: The activation treatment includes plasma treatment; Preferably, the plasma treatment includes air ionization or introducing external gas for ionization; the external gas includes one or more of argon, nitrogen and oxygen; the ionization condition is: voltage 10~5000V.

5. The composite integrated film according to any one of claims 1 to 4, characterized in that: The thickness of the composite integrated film is 0.15-4.00 mm; Preferably, the thickness of the first packaging film layer is 0.10-0.95 mm; Preferably, the thickness of the fluorine-containing film layer after the activation treatment is 0.05-3.00 mm.

6. The composite integrated film according to any one of claims 1 to 5, characterized in that: The material of the first encapsulation film layer includes at least one of EVA, POE, PE, PVB, PMMA, PC, POP, EAA, EMA, EBA, EMH and TPU, more preferably at least one of EVA, POE and PVB; And / or, the fluorine-containing film layer material includes at least one of ETFE, PTFE, PVDF, and PVF; And / or, another encapsulation film layer is stacked on the side of the first encapsulation film layer away from the fluorine-containing thin film layer; the number of layers of the another encapsulation film layer is more than one; Preferably, the material of the first encapsulation film layer is the same as or different from the material of the other encapsulation film layers and includes at least one of EVA, POE, PE, PVB, PMMA, PC, POP, EAA, EMA, EBA, EMH and TPU, more preferably at least one of EVA, POE and PVB; And / or, the side of the fluorine-containing thin film layer away from the first encapsulation film layer is further provided with an outer film; the number of layers of the outer film is more than one; Preferably, the material of the outer membrane includes at least one of ETFE, PTFE, PVDF, PVF, PET, and PI; More preferably, the material of the outer film includes a composite film of at least one of ETFE, PTFE, PVDF, PVF and PET, and the PET is disposed close to the fluorine-containing film.

7. The method for preparing the composite integrated membrane according to any one of claims 1 to 6, characterized in that: include: S1: activating the surface of the fluorine-containing thin film layer close to the first packaging film to obtain an activated fluorine-containing thin film layer; S2: casting or laminating the melted material of the first packaging film onto the surface of the activated fluorine-containing film layer to obtain a composite film; S3: performing a composite treatment on the composite film to obtain the composite integrated film; wherein the surface hardness of the first packaging film is 45-80HA; Alternatively, the method for preparing the composite integrated membrane comprises: S1': activating the surface of the fluorine-containing thin film layer close to the first packaging film to obtain an activated fluorine-containing thin film layer; S2': laminating and pressing the first packaging film and the activated fluorine-containing film layer to obtain a composite film; S3': performing a composite treatment on the composite film to obtain the composite integrated film; wherein the surface hardness of the first packaging film is 45-80HA; Preferably, the composite treatment comprises a baking treatment or an electron beam treatment; More preferably, the baking treatment comprises baking the composite film at 80° C. to 100° C. for 3 to 10 min; and / or the electron beam treatment comprises irradiating the composite film with an electron beam having an irradiation amount of 2 to 50 KGY.

8. The method for preparing the composite integrated membrane according to claim 7, characterized in that: The fluorine-containing film layer is obtained by at least one method selected from the group consisting of extrusion, film blowing, molding, rolling, injection molding, casting, and stretching, or by coating and curing the coating to form a film; Preferably, an outer film is further provided on the side of the fluorine-containing film layer away from the first encapsulation film layer, and the fluorine-containing film layer is obtained by coating a coating on the outer film and curing the coating to form a film.

9. The method for preparing the composite integrated membrane according to claim 7 or 8, characterized in that: The method further comprises S4: casting, laminating and pressing at least one other encapsulating film layer on the surface of the first encapsulating film away from the fluorine-containing film layer.

10. A photovoltaic module, characterized in that: A composite integrated film comprising any one of claims 1 to 6 or a composite integrated film prepared by the preparation method of any one of claims 7 to 9; Preferably, the structure of the photovoltaic module includes the composite integrated film, the battery cell, the back packaging film and the back plate laminated in sequence; preferably, the light transmittance of the composite integrated film is ≥85%.

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