Composition with high volume resistivity, packaging adhesive film and solar module

Abstract

The invention relates to the technical field of photovoltaics, and particularly discloses a composition with high volume resistivity, a packaging adhesive film and a solar module. The invention relates to a composition with high volume resistivity. The composition comprises polyolefin resin, a cross-linking agent and a fluorine-containing auxiliary agent, the general formula of the fluorine-containing auxiliary agent is as shown in formula 1; wherein Ar is selected from one of an acrylate group, a methacrylate group, a triethoxysilyl group and a trimethoxysilyl group; at least one of R1, R2 and R3 represents a fluorine atom; and n is 1-20. The maximum volume resistivity of the packaging adhesive film can reach 52.6 * 10 < 16 > omega.cm, and the resistivity of the packaging adhesive film is improved; and the obtained packaging adhesive film can resist PID192H of 1.02%, the breakdown voltage is up to 75 Kv / mm, and the packaging adhesive film has relatively high PID resistance and insulating property.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and more specifically, to a high volume resistivity composition, a packaging film and a solar cell module. Background Art

[0002] The main component of solar photovoltaic cell modules is solar cells, which cannot be directly exposed to natural conditions such as sunlight and rain. Therefore, in practical applications, encapsulation film is used to bond photovoltaic glass, solar cells and back panels together. Encapsulation film is a thermosetting and sticky film, which is an important encapsulation material in photovoltaic encapsulation. It is used to bond photovoltaic cells to photovoltaic glass and back panels, protect the cells and encapsulate them into photovoltaic modules that can output direct current. The volume resistivity of the encapsulation film affects the ion mobility of the encapsulation film. A high volume resistivity can reduce the ion mobility of the encapsulation film and alleviate the leakage phenomenon caused by poor insulation.

[0003] At present, the volume resistivity of the encapsulation film is relatively low. For example, the volume resistivity of EVA (ethylene vinyl acetate copolymer) encapsulation film is about 1.0×10 15 Ω·cm, the volume resistivity of POE (ethylene-a-olefin) packaging film is about 1.0×10 16 About Ω·cm, polyolefin synthesis manufacturers improve the volume resistivity of polyolefins by modifying and polymerizing metal catalysts, but this often leads to an increase in production costs and it is difficult to further increase it. Summary of the invention

[0004] In order to increase the volume resistivity of an encapsulation film, the present application provides a composition with high volume resistivity, an encapsulation film and a solar cell module.

[0005] In a first aspect, the present application provides a composition with high volume resistivity, which adopts the following technical solution: A high volume resistivity composition comprises a polyolefin resin, a crosslinking agent and a fluorine-containing auxiliary agent; the general structural formula of the fluorine-containing auxiliary agent is as follows: Wherein, Ar is selected from one of acrylate, methacrylate, and triethoxysilyl; R1, R2, and R3 represent a hydrogen atom or a fluorine atom respectively; n is 1-20.

[0006] By adopting the above technical solution, the electronegativity of fluorine is very high, which can attract surrounding electrons. It is an electron-withdrawing functional group, which will produce a strong electron-withdrawing effect, and thus absorb free electrons. In addition, fluorine-containing organic matter also contains a carbon-fluorine bond, which is an extremely stable chemical bond with lower HOMO (highest occupied orbital) and LUMO (lowest unoccupied orbital) energy levels. The lower the HOMO (highest occupied orbital) energy level, the less likely it is to lose electrons, and the lower the LUMO energy level, the easier it is to get electrons. Since the LUMO energy level of the CF bond is low, it is easier to attract free electrons. At the same time, since the HOMO energy level of the CF bond is low, it means that the electron binding effect is strong, and the attracted electrons are not easy to lose again, so the number of free electrons is reduced and the volume resistivity is increased. The compound selected with this structure has good electrical insulation and voltage resistance.

[0007] The carbon-fluorine bond is one of the strongest chemical bonds, and the CF bond will be strengthened as the number of fluorine atoms attached to the carbon increases. Thus, it shows strong resistance to breakdown. Furthermore, since the HOMO energy of the CF bond is low, it means that the atomic nucleus has a strong binding effect on the valence electrons, and the electron cloud distribution is not easily affected by the outside world, that is, the polarizability is weak. The polarizability directly affects the intermolecular force, so the force between the fluorine atom and the hydrogen atom in the water molecule is weak, which plays a hydrophobic role and helps to resist PID.

[0008] In addition, the fluorine-containing auxiliary agent in the raw material of the encapsulation film composition of the present application can be selected from one of fluorine-containing acrylate and fluorine-containing silane, or can be added at the same time. Adding them at the same time can further improve the volume resistivity of the encapsulation film, and the resulting composition has simple components, easy-to-obtain raw materials, few process steps, and low cost.

[0009] Preferably, when Ar is an acrylate group, the fluorine-containing auxiliary agent is selected from at least one of trifluoroethyl acrylate, hexafluorobutyl acrylate, and dodecafluoroheptyl acrylate.

[0010] When the fluorine-containing auxiliary agent in the raw material of the encapsulating film composition of the present application is selected from any one of trifluoroethyl acrylate, hexafluorobutyl acrylate, and dodecafluoroheptyl acrylate, the encapsulating film has a relatively high volume resistivity.

[0011] Preferably, when Ar is a methacrylate group, the fluorine-containing auxiliary agent is selected from at least one of tridecafluorooctyl methacrylate, trifluoroethyl methacrylate, hexafluorobutyl methacrylate, and dodecafluoroheptyl methacrylate.

[0012] When the fluorine-containing auxiliary agent in the raw material of the encapsulating film composition of the present application is selected from any one of tridecafluorooctyl methacrylate, trifluoroethyl methacrylate, hexafluorobutyl methacrylate, and dodecafluoroheptyl methacrylate, the encapsulating film has a relatively high volume resistivity.

[0013] By adopting the above technical solution, when Ar is an acrylate group or a methacrylate group, it can undergo a cross-linking reaction with the polyolefin resin and be evenly distributed in the film, thereby improving the volume resistivity of the packaging film.

[0014] Preferably, when Ar is a triethoxysilyl group, the fluorine-containing auxiliary agent is selected from at least one of hexafluorobutyltriethoxysilane, dodecafluoroheptyltriethoxysilane, tridecafluorooctyltriethoxysilane and heptadecafluorodecyltriethoxysilane.

[0015] When the fluorine-containing auxiliary agent in the raw materials of the encapsulation film composition of the present application is selected from any one of hexafluorobutyltriethoxysilane, dodecafluoroheptyltriethoxysilane, tridecafluorooctyltriethoxysilane, and heptadecafluorodecyltriethoxysilane, the encapsulation film has a relatively high volume resistivity.

[0016] Preferably, when Ar is a trimethoxysilyl group, the fluorine-containing auxiliary agent is selected from at least one of hexafluorobutyltrimethoxysilane, dodecafluoroheptyltrimethoxysilane, tridecafluorooctyltrimethoxysilane and heptadecafluorodecyltrimethoxysilane.

[0017] When the fluorine-containing auxiliary agent in the raw materials of the encapsulation film composition of the present application is selected from any one of hexafluorobutyltrimethoxysilane, dodecafluoroheptyltrimethoxysilane, tridecafluorooctyltrimethoxysilane, and heptadecafluorodecyltrimethoxysilane, the encapsulation film has a relatively high volume resistivity.

[0018] By adopting the above technical solution, when Ar is triethoxysilyl or trimethoxysilyl, it can undergo a cross-linking reaction with the polyolefin resin and be evenly distributed in the film, thereby increasing the volume resistivity of the packaging film.

[0019] Preferably, the composition comprises, by weight, 100 parts of polyolefin resin, 0.1-2 parts of cross-linking agent and 0.05-1 parts of fluorine-containing auxiliary agent.

[0020] The raw materials of the encapsulating film composition of the present application can be selected from 100 parts of base resin and 0.1-2 parts of cross-linking agent; the composition also includes 0.05-1 part of fluorine-containing auxiliary agent, and any value within the respective ranges can be selected, and both can improve the high volume resistivity of the composition, thereby improving the volume resistivity of the encapsulating film.

[0021] Preferably, the polyolefin resin is at least one selected from ethylene vinyl acetate copolymer, ethylene-α-olefin copolymer, ethylene butene copolymer, ethylene octene copolymer, ethylene pentene copolymer, ethylene methyl acrylate copolymer and ethylene methyl methacrylate copolymer.

[0022] The polyolefin resin in the raw material of the encapsulating film composition of the present application is selected from any one of ethylene vinyl acetate copolymer, ethylene-α-olefin copolymer, ethylene butene copolymer, ethylene octene copolymer, ethylene pentene copolymer, ethylene methyl acrylate copolymer and ethylene methyl methacrylate copolymer, and the encapsulating film has a high volume resistivity.

[0023] Preferably, the composition further comprises 0.5-5 parts by weight of an auxiliary agent; the auxiliary agent is selected from one or more of an antioxidant, a hindered amine light stabilizer, an ultraviolet light absorber, and a tackifier.

[0024] In the present application, the volume resistivity of the encapsulation film can be increased by selecting any value of 0.5-5 parts by weight of the auxiliary agent.

[0025] By adopting the above technical solution, antioxidants, hindered amine light stabilizers, ultraviolet light absorbers, tackifiers and other additives can be added according to the actual use requirements of the packaging film to make the packaging film have different properties.

[0026] In a second aspect, the present application provides a packaging film, which adopts the following technical solution: A packaging adhesive film is prepared from the composition of the first aspect.

[0027] A packaging film is obtained by the following steps: mixing raw materials except a crosslinking agent of the composition, grafting and granulating, adding other raw materials to the grafted particles, mixing and melt extruding, such as a crosslinking agent and an auxiliary agent, casting into a film after mixing, and irradiating to obtain the packaging film.

[0028] In a third aspect, the present application provides a solar panel, which adopts the following technical solution: A solar energy component comprises the packaging film of the second aspect.

[0029] Specifically: Solar panels are generally divided into double-glass solar panels and single-glass solar panels according to the number of glass cover sheets. Among them, double-glass solar panels include solar cells, double-glass cover sheets and packaging films. The packaging films are packaged on both sides of the solar cells. The double-glass cover sheets are bonded to the upper and lower sides of the solar cells. The packaging films are located between the solar cells and the glass cover sheets. Single-glass solar panels include solar cells, glass cover sheets, back sheets and packaging films. The packaging films are packaged on both sides of the solar cells. The glass cover sheets are bonded to one side of the solar cells and the other side is bonded to the back sheet. The packaging films are located between the solar cells and the glass cover sheets or between the solar cells and the back sheet.

[0030] In summary, this application has the following beneficial effects: (1) The present application adds a fluorine-containing auxiliary agent to the raw material of the encapsulating film, wherein the fluorine-containing auxiliary agent is a fluorine-containing acrylate, and controls the amount of the fluorine-containing auxiliary agent, so that the volume resistivity of the encapsulating film reaches 31.4×1016 Ω.cm, which improves the resistivity of the packaging film.

[0031] (2) The present application adds a fluorine-containing auxiliary agent to the raw material of the encapsulating film, wherein the fluorine-containing auxiliary agent is a fluorine-containing silane, and controls its dosage, so that the volume resistivity of the encapsulating film reaches 21.5×10 16 Ω.cm, which improves the resistivity of the packaging film.

[0032] (3) In the present application, by reducing the dosage of fluorinated acrylate or fluorinated silane, the volume resistivity of the encapsulation film obtained is 7.4×10 16 Ω.cm-8.3×10 16 Ω.cm, still meets the usage requirements of the volume resistivity of the packaging film.

[0033] (4) In the present application, by simultaneously adding fluorinated acrylate and fluorinated silane to the raw material of the encapsulation film, the volume resistivity of the encapsulation film obtained is 52.6×10 16 Ω.cm, further improving the volume resistivity of the packaging film.

[0034] (5) The encapsulation film obtained in the present application has a power attenuation of 1.02% after PID192H and a maximum breakdown voltage of 75Kv / mm, and has high anti-PID performance and insulation performance. DETAILED DESCRIPTION

[0035] The present application is further described in detail below with reference to the embodiments.

[0036] The following raw materials in this application are all commercially available products, and are all for the purpose of making the raw materials of this application fully disclosed, and should not be understood as limiting the source of the raw materials, specifically: polyolefin resin, selected from ethylene-a-olefin and ethylene-vinyl acetate copolymer, wherein ethylene-a-olefin, brand Mitsui Chemicals, grade A-20070S; ethylene-vinyl acetate copolymer, vinyl acetate content of 18%. Crosslinking agent, selected from triallyl isocyanurate, effective substance content of 98%; fluorinated acrylate, selected from hexafluorobutyl acrylate, methacrylate tridecafluorooctyl ester and fluorine-modified polyurethane acrylate, wherein hexafluorobutyl acrylate, molecular weight of 236, effective substance content ≥96%; methacrylate tridecafluorooctyl ester, molecular weight of 418, effective substance content ≥96%; fluorine-modified polyurethane acrylate, purchased from Changxing Chemical Industry (China) Co., Ltd., model 61998. Fluorosilanes used include hexafluorobutyltriethoxysilane and tridecafluorooctyltriethoxysilane, both of which are purchased from Harbin Xuejia Fluorosilicon Co., Ltd. Among them, hexafluorobutyltriethoxysilane has a molecular weight of 356 and an effective substance content of ≥98%; tridecafluorooctyltriethoxysilane has a molecular weight of 510 and an effective substance content of ≥95%; the antioxidant is tert-butyl peroxy 2-ethylhexyl carbonate, with an effective substance content of 99%; the viscosity enhancer is γ-methacryloxypropyltrimethoxysilane, with an effective substance content of 45%.

[0037] Example 1 The encapsulation film of Example 1 is prepared by the following steps: According to the dosage in Table 1, the raw materials of the composition except the crosslinking agent are mixed, grafted and granulated, the crosslinking agent is added to the grafted particles, mixed and melted and extruded, mixed and cast into a film, and irradiated to obtain the encapsulation film. The polyolefin resin is ethylene-α-olefin copolymer, the crosslinking agent is triallyl isocyanurate, the fluorine-containing auxiliary agent is fluorine-containing acrylate, specifically hexafluorobutyl acrylate; the antioxidant is tert-butyl peroxy 2-ethylhexyl carbonate; the tackifier is γ-methacryloxypropyl trimethoxysilane.

[0038] Example 2 The encapsulation film of Example 2 is prepared by the following steps: According to the dosage in Table 1, the raw materials of the composition except the crosslinking agent are mixed, grafted and granulated, the crosslinking agent, antioxidant and tackifier are added to the grafted particles, mixed and melted and extruded, cast into a film after mixing, and irradiated to obtain the packaging film. The polyolefin resin is ethylene-α-olefin copolymer, the crosslinking agent is triallyl isocyanurate, and the fluorinated acrylate is hexafluorobutyl acrylate.

[0039] Embodiment 3-4 The preparation methods of the encapsulation films of Examples 3-4 are exactly the same as those of Example 2, except that hexafluorobutyl acrylate is replaced by equal amounts of tridecafluorooctyl methacrylate and fluorine-modified polyurethane acrylate, as shown in Table 1.

[0040] Table 1 Amount of each raw material in the encapsulation film composition of Examples 1-4 (unit: kg) Embodiment 5-6 The preparation method of the encapsulating film of Examples 5-6 is exactly the same as that of Example 3, except that no fluorinated acrylate is added to the raw materials of the encapsulating film composition, and the fluorinated acrylate is replaced by hexafluorobutyltriethoxysilane and tridecafluorooctyltriethoxysilane in equal amounts, as shown in Table 2 for details.

[0041] Table 2 Amount of each raw material in the encapsulation film composition of Examples 5-6 (unit: kg) Example 7 The preparation method of the encapsulating film of Example 7 is exactly the same as that of Example 6, except that 0.5 kg of tridecafluorooctyl methacrylate in the raw material of the encapsulating film composition is replaced by 0.1 kg of tridecafluorooctyl methacrylate.

[0042] Example 8 The preparation method of the encapsulating film of Example 8 is exactly the same as that of Example 6, except that 0.5 kg of tridecafluorooctyltriethoxysilane in the raw material of the encapsulating film composition is replaced by 0.1 kg of tridecafluorooctyltriethoxysilane.

[0043] Example 9 The preparation method of the encapsulating film of Example 9 is exactly the same as that of Example 6, except that the raw materials of the encapsulating film composition further include 0.5 kg of fluorinated acrylate (tridecafluorooctyl methacrylate), and the types and dosages of other raw materials are the same as those of Example 6.

[0044] Example 10 The preparation method of the encapsulating film of Example 10 is exactly the same as that of Example 2, except that the polyolefin resin ethylene-α-olefin copolymer in the raw material of the encapsulating film composition is replaced by ethylene vinyl acetate copolymer in equal amounts, and the types and dosages of other raw materials are the same as those of Example 9.

[0045] Comparative Example 1 The preparation method of the encapsulating film of Comparative Example 1 is exactly the same as that of Example 2, except that no fluorinated acrylate (hexafluorobutyl acrylate) is added to the raw materials of the encapsulating film composition, and the other raw materials and dosages are the same as those of Example 1.

[0046] Comparative Example 2 The preparation method of the encapsulation film of Comparative Example 2 is exactly the same as that of Example 5, except that no fluorine-containing silane (tridecafluorooctyltriethoxysilane) is added to the raw materials of the encapsulation film composition, and the remaining raw materials and dosages are the same as those of Example 1.

[0047] Comparative Example 3 The preparation method of the encapsulating film of Comparative Example 3 is exactly the same as that of Example 10, except that no fluorinated acrylate (hexafluorobutyl acrylate) is added to the raw materials of the encapsulating film composition, and the remaining raw materials and dosages are the same as those of Example 10.

[0048] Performance Testing The following testing standards or methods were used to test the performance of the encapsulation films obtained in different embodiments 1-10 and comparative examples 1-3. The thickness of the obtained encapsulation films was 200-500 μm. The test results are shown in Table 3.

[0049] Volume resistivity: The volume resistivity of the encapsulation film was tested in accordance with GB / T 29848-2013 standard, with the test temperature at 23±2℃ and 40%-60%RH.

[0050] Anti-PID test: According to the IEC TS2804-1:2015 standard, the PID resistance of the encapsulation film was tested for 192 hours, the test temperature was 85°C, the relative humidity was 85%, and a bias of -2000V was applied at the same time. After 192 hours, the double-sided power attenuation of the solar module before and after the test was tested. The solar module includes a cell, a double glass cover and an encapsulation film. The encapsulation film is encapsulated on both sides of the cell, the double glass cover is bonded to the upper and lower sides of the cell, and the encapsulation film is located between the cell and the glass cover.

[0051] Breakdown voltage: The breakdown voltage of the packaging film is tested in accordance with GB / T 1408.1-2006 standard.

[0052] Table 3 Performance test results of different encapsulation films The test results in Table 3 show that the volume resistivity of the encapsulation film obtained in this application can reach up to 52.6×10 16 Ω.cm, which improves the resistivity of the packaging film; and the obtained packaging film has a power attenuation of 1.02% after PID192H resistance, a breakdown voltage of 75Kv / mm, and has high anti-PID performance and insulation performance.

[0053] Combined with the performance tests of Example 1 and Example 2-4, it was found that when fluorinated acrylate was added to the raw material of the encapsulating film without adding antioxidant and tackifier, the volume resistivity and PID192H resistance of the encapsulating film were 11.0×10 16 Ω.cm and 2.34%, and had no significant effect on volume resistivity and anti-PID performance. Therefore, during production, antioxidants, hindered amine light stabilizers, ultraviolet light absorbers, tackifiers and other additives can be selectively added according to actual production needs.

[0054] In Examples 2-4, the volume resistivity of the encapsulation film obtained in Example 3 is 31.4×10 16 Ω.cm, which is higher than that of Example 2 and Example 4, indicating that when the fluorinated acrylate in the raw material of the encapsulation film is selected as tridecafluorooctyl methacrylate, the volume resistivity of the encapsulation film can be further improved.

[0055] In Examples 5-6, the volume resistivity of the encapsulation film obtained in Example 6 is 21.5×10 16 Ω.cm, which is higher than that of Example 5, indicating that when tridecafluorooctyltriethoxysilane is used as the fluorine-containing silane in the raw material of the encapsulation film, the volume resistivity of the encapsulation film can be further improved.

[0056] The encapsulation films of Examples 7-8 all reduced the dosage of tridecafluorooctyl methacrylate or tridecafluorooctyl triethoxysilane to 0.1 kg, and the volume resistivity of the obtained encapsulation films was 7.4×10 16 Ω.cm-8.3×10 16 Ω.cm, still meets the usage requirements of the volume resistivity of the packaging film.

[0057] Combining the performance test data of the packaging film of Example 9 with that of Example 6, it is found that the volume resistivity of the packaging film obtained by adding fluorinated acrylate and fluorinated silane to the raw material of the packaging film of Example 9 is 52.6×10 16 Ω.cm, which is higher than that of Example 6, indicating that the volume resistivity of the encapsulation film can be further improved by adding fluorinated acrylate and fluorinated silane.

[0058] Combining the performance test data of the packaging film of Example 10 and Example 2, it is found that in Example 10, the volume resistivity of the packaging film obtained by replacing the polyolefin resin ethylene-α-olefin copolymer with ethylene vinyl acetate copolymer is 1.8×10 16 Ω.cm, which is significantly lower than that in Example 2. This may be related to the fact that the ethylene-α-olefin copolymer particles are non-polar resins, and the ethylene-vinyl acetate copolymer particles are polar resins, and the ethylene-α-olefin copolymer particles move slowly and have a longer polarization time constant, thus increasing the volume resistivity of the encapsulation film.

[0059] Combining the performance test data of the packaging films of Example 1 and Comparative Examples 1-3, it is found that adding fluorinated acrylate and fluorinated silane to the raw materials of the packaging films can increase the volume resistivity of the packaging films to varying degrees.

[0060] The following are the applications of encapsulation films in solar panels Application Example 1 Application Example 1 The application of encapsulation film in solar panels is specifically as follows: the solar panel includes a battery cell, a double glass cover and an encapsulation film, the encapsulation film is encapsulated on both sides of the battery cell, the double glass cover is bonded to the upper and lower sides of the battery cell, and the encapsulation film is located between the battery cell and the glass cover.

[0061] Application Example 2 Application Example 2 The application of encapsulation film in solar modules is specifically as follows: the solar module includes a battery cell, a glass cover, a back panel and an encapsulation film, the encapsulation film is encapsulated on both sides of the battery cell, the glass cover is bonded to one side of the battery cell and the other side is bonded to the back panel, and the encapsulation film is located between the battery cell and the glass cover or between the battery and the back panel.

[0062] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A composition with high volume resistivity, characterized in that: It comprises a polyolefin resin, a crosslinking agent and a fluorine-containing auxiliary agent; the general structural formula of the fluorine-containing auxiliary agent is as follows: Wherein, Ar is selected from one of acrylate, methacrylate, triethoxysilyl and trimethoxysilyl; At least one of R1, R2 and R3 represents a fluorine atom; n is 1-20.

2. The high volume resistivity composition according to claim 1, characterized in that: When Ar is an acrylate group, the fluorine-containing auxiliary agent is selected from at least one of trifluoroethyl acrylate, hexafluorobutyl acrylate, and dodecafluoroheptyl acrylate.

3. The high volume resistivity composition according to claim 1, characterized in that: When Ar is a methacrylate group, the fluorine-containing auxiliary agent is selected from at least one of tridecafluorooctyl methacrylate, trifluoroethyl methacrylate, hexafluorobutyl methacrylate, and dodecafluoroheptyl methacrylate.

4. The high volume resistivity composition according to claim 1, characterized in that: When Ar is a triethoxysilyl group, the fluorine-containing auxiliary agent is selected from at least one of hexafluorobutyltriethoxysilane, dodecafluoroheptyltriethoxysilane, tridecafluorooctyltriethoxysilane and heptadecafluorodecyltriethoxysilane.

5. The high volume resistivity composition according to claim 1, characterized in that: When Ar is a trimethoxysilyl group, the fluorine-containing auxiliary agent is selected from at least one of hexafluorobutyltrimethoxysilane, dodecafluoroheptyltrimethoxysilane, tridecafluorooctyltrimethoxysilane and heptadecafluorodecyltrimethoxysilane.

6. The high volume resistivity composition according to any one of claims 1 to 5, characterized in that: Calculated by weight, it includes 100 parts of polyolefin resin, 0.1-2 parts of cross-linking agent and 0.05-1 part of fluorine-containing auxiliary agent.

7. The high volume resistivity composition according to claim 6, characterized in that: The polyolefin resin is at least one selected from ethylene vinyl acetate copolymer, ethylene-α-olefin copolymer, ethylene butene copolymer, ethylene octene copolymer, ethylene pentene copolymer, ethylene methyl acrylate copolymer and ethylene methyl methacrylate copolymer.

8. The high volume resistivity composition according to claim 6, characterized in that: The composition further comprises 0.5-5 parts by weight of an auxiliary agent; the auxiliary agent is selected from one or more of an antioxidant, a hindered amine light stabilizer, an ultraviolet light absorber, and a tackifier.

9. A packaging film, characterized in that: The encapsulation film is prepared from the composition according to any one of claims 1-8.

10. A solar panel, characterized in that: The encapsulation film comprises the encapsulation film as claimed in claim 9.

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