Modified POE (Polyolefin Elastomer) composition, adhesive film as well as preparation method and application of modified POE composition

Abstract

The invention provides a modified POE composition, an adhesive film and a preparation method and application thereof, the modified POE composition contains POE and copolymer microspheres containing at least one group including anhydride and imide, and the copolymer is a carbon chain polymer; the mass ratio of the copolymer microspheres to the POE is (0.05-20): 100. The modified POE composition and the adhesive film can simultaneously realize ultraviolet absorption, ultraviolet light conversion, high haze and polarity improvement under the condition of keeping a certain light transmittance, and can improve the use performance and the service life of the POE adhesive film in a practical application scene.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of high polymer materials, and particularly relates to a modified POE composition, a film and a preparation method and application thereof. BACKGROUND

[0002] Polyolefin elastomer (POE) is a random copolymer of ethylene / 1-octene, ethylene / 1-hexene, ethylene / 1-butene, the main chain is saturated structure, has low water vapor permeability, good aging resistance and other advantages. The linear long chain structure of the side chain not only improves the processing rheology, but also further weakens the regularity of the polyethylene crystal region, and improves the transparency of the product. At present, it has great application prospect in replacing EVA as photovoltaic cell packaging film.

[0003] The performance of photovoltaic film is closely related to the service life of solar cells, and POE usually needs to add other additives when used as photovoltaic film, such as antioxidants, light stabilizers, ultraviolet absorbers, crosslinking agents, and crosslinking aids. These additives are usually small molecules with polarity, and it is not easy to disperse polar additives during processing with non-polar POE, which causes surface migration of additives during use of POE film, degradation of film quality, and reduction of photovoltaic cell life. To improve this problem, a compatibilizer can be added to the POE film for further modification, such as EMMA, EVA-g-MAH and POE blending melt modification by Wang Yue et al. By introducing the compatibilizer EVA-g-MAH, the tensile strength, elongation at break and peel strength of the POE film are improved (Wang Yue, Wang Xian-ni, Guo Qian, et al. Performance of POE film for photovoltaic cell packaging modified by EMMA [J]. Modern Plastics Processing and Application, 2023, 35(02): 16-19). Patent CN 112341700 A discloses a POE packaging film for improving the conversion power of solar modules, which improves the polarity of the POE film by silane, and the output power attenuation is reduced to 2.2% after 192h of PID test.

[0004] In addition to improving the performance of encapsulating films to further extend the lifespan of solar cells and reduce costs and increase efficiency, improving the photoelectric conversion efficiency of solar cells has also been a development direction in recent years. At present, common methods include broadening the spectral response band of photovoltaic cells, surface morphology to reduce light reflection, and improving current output methods. Among these, surface morphology is a more universal method. Existing surface morphology methods include texturing the surface of the photovoltaic module itself and chemically depositing anti-reflective coatings with gradient refractive indices. However, the above methods all have problems such as complex processes, low processing efficiency, and high production costs. Hou Gaoyuan et al. discovered a cellulose film that, while maintaining a certain transmittance, improves the conversion efficiency of photovoltaic modules by increasing the haze of the film. After being attached to gallium arsenide solar cells, the short-circuit current increased by 18%, effectively improving the absorption and capture capabilities of photovoltaic modules (Hou Gaoyuan, Li Guanhui, Hu Zhaoxiang et al. Preparation, performance and application of high haze transparent cellulose film in solar cells [J]. Journal of Composite Materials, 2022, 39(05): 1907-1923). However, further research is needed on how to further improve the performance of POE film, extend its service life, and increase the efficiency of photovoltaic modules. Summary of the Invention

[0005] This invention provides a modified POE composition, a film, its preparation method, and its applications. The modified POE composition and film of this invention can simultaneously achieve ultraviolet absorption, ultraviolet conversion, high haze, and improved polarity while maintaining a certain level of light transmittance. The ultraviolet absorption and ultraviolet conversion enhance solar energy utilization; the improved haze while maintaining a certain level of light transmittance improves the conversion efficiency of photovoltaic modules; and the improved polarity of the POE composition increases the peel strength of POE to other non-polar materials and improves the dispersibility of small-molecule polar additives in non-polar POE, thereby further improving the performance and lifespan of the POE film in practical applications.

[0006] To achieve the above-mentioned objective, a first aspect of the present invention is to provide a modified POE composition comprising POE and copolymer microspheres containing at least one group including an anhydride and an imide, wherein the copolymer is a carbon chain polymer.

[0007] The mass ratio of the copolymer microspheres to POE is (0.05-20):100.

[0008] According to the present invention, the polymer is a carbon chain polymer, wherein heteroatoms O and N are present in the side groups.

[0009] In this invention, the acid anhydride group refers to the group -CO-O-CO-, and the imide group refers to a group in which a nitrogen atom is attached to two carbonyl groups. For example, the maleic anhydride group refers to... The maleimide group refers to

[0010] The inventors believe that the advantages of this invention are due to the following: By incorporating copolymer microspheres containing at least one group, including anhydride and imide, into POE, the anhydride, as a polar group, effectively improves the non-polarity of POE, increases its peel strength against other non-polar materials, and improves the dispersibility of small-molecule polar additives in non-polar POE, thereby enhancing the performance of the encapsulant film. Simultaneously, the introduction of the microsphere structure can increase the haze of the encapsulant film while maintaining sufficient light transmittance, thus increasing the conversion efficiency of the photovoltaic module. Furthermore, the anhydride structure and the imide structure modified by the anhydride group can absorb ultraviolet light below 280nm and convert light in the 290-400nm band to above 420nm, extending the lifespan of the POE encapsulant film and the photovoltaic module, further improving the efficiency of the photovoltaic module. More specifically:

[0011] The modified POE composition contains anhydride groups and / or further modified imide groups, wherein lone pairs of electrons exist on both O and N, increasing polarity and improving the compatibility of nonpolar POE with various polar additives. Furthermore, the copolymer containing anhydride groups in the modified POE film is preferably obtained by polymerizing a monomer containing anhydride groups with one or more monomers containing isolated carbon-carbon double bonds. The monomer-derived structural units containing isolated carbon-carbon double bonds increase compatibility with POE. Moreover, the addition of anhydride and imide groups to the polymer microspheres, presenting them in a high molecular structure, prevents migration within the POE matrix and simultaneously improves the problem of small molecule additive surface precipitation. Compared to increasing POE polarity by grafting polar groups, the blending modification process is simpler, produces a more uniform distribution of polar functional groups, and is more universally applicable.

[0012] According to the present invention, in the modified POE composition: a copolymer containing POE and at least one group including anhydride and imide is uniformly dispersed in POE in the form of microspheres.

[0013] According to some preferred embodiments of the present invention, the mass ratio of the copolymer containing at least one group including anhydride and imide to POE is (0.1-10):100, for example 0.1, 0.3, 0.5, 0.8, 1, 3, 5, 7, 10, and any two values ​​or any range of any two values ​​to 100; preferably (0.5-5):100.

[0014] According to some preferred embodiments of the present invention, the copolymer containing at least one group including anhydride and imide is an anhydride copolymer and / or an imidized product of an anhydride copolymer.

[0015] The modified POE film contains anhydride groups and / or further modified imide groups, forming a spherical structure that can be uniformly dispersed in POE. By using microspheres with optimized micro / nano structures, a film with both high transmittance and high haze is prepared, improving the transmittance of wide-angle incident light and increasing the forward scattering of incident light. To further improve haze while maintaining high transmittance, the average particle size of the microspheres is preferably 400 nm-3 μm, more preferably 500 nm-2 μm, with 600 nm to 1 μm being optimal. According to some preferred embodiments of the present invention, the average particle size of the copolymer microspheres is preferably 400 nm-3 μm, for example 400 nm, 500 nm, 600 nm, 800 nm, 1 μm, 1.5 μm, 2 μm, 3 μm, and any two values ​​or any range of any two values, more preferably 500 nm-2 μm, and most preferably 600 nm-1 μm.

[0016] According to some preferred embodiments of the present invention, anhydride copolymers are obtained by polymerization of monomers containing anhydride groups with one or more monomers containing isolated carbon-carbon double bonds.

[0017] According to some preferred embodiments of the present invention, the anhydride copolymers may have a cross-linked or non-cross-linked structure. The present invention does not impose any particular limitation on whether they are cross-linked, as long as they exist in the form of microspheres.

[0018] According to some preferred embodiments of the present invention, the anhydride copolymer contains structural units derived from monomers containing anhydride groups and structural units derived from one or more monomers containing isolated carbon-carbon double bonds; more preferably, the molar content of the anhydride groups is 20%-80%, preferably 30%-70%, more preferably 40%-60%, based on the total molar content of all structural units in the anhydride copolymer being 100%; even more preferably, the anhydride copolymer has a structure in which monomers containing anhydride groups and monomers containing isolated carbon-carbon double bonds are alternately copolymerized.

[0019] According to some preferred embodiments of the present invention, the monomer containing anhydride groups contains anhydride groups and isolated carbon-carbon double bonds, preferably selected from at least one of maleic anhydride, itaconic anhydride, and citraconic anhydride, more preferably maleic anhydride.

[0020] According to some preferred embodiments of the present invention, the monomer containing an isolated carbon-carbon double bond is selected from at least one of C2-C9 olefins, C4 fraction, C5 fraction, C8 fraction, C9 fraction, and vinyl acetate; preferably at least one of styrene, α-methylstyrene, isobutylene, C4 fraction, and C8 fraction.

[0021] According to the present invention, C2-C9 can be C2 olefin, C3 olefin, C4 olefin, C5 olefin, C6 olefin, C7 olefin, C8 olefin, or C9 olefin, and can be a single olefin or a mixture of olefins.

[0022] For example, the C4 and C5 fractions are selected from C4 or C5 fractions from the oil refining or ethylene industry, preferably from C4 or C5 fractions obtained from ethylene cracking in the petrochemical industry; the C8 and C9 fractions are selected from C8 or C9 fractions from the steam cracking process for ethylene production in the petrochemical industry, the naphtha platinum reforming process, and coal tar.

[0023] The anhydride copolymers described in this invention can be prepared using commercially available or existing technologies, and the preparation methods include, but are not limited to, the preparation methods used in the embodiments of this invention.

[0024] According to some preferred embodiments of the present invention, the anhydride copolymer is obtained by copolymerization via self-stabilizing precipitation polymerization.

[0025] According to some preferred embodiments of the present invention, the anhydride groups can be partially modified, that is, the copolymer containing anhydride groups consists of at least anhydride group x and an imide group y obtained by further modification of the anhydride groups, and the range of y / x can be 5 / 100-95 / 100. That is, when the copolymer containing at least one group including anhydride and imide is an imidized product of anhydride copolymer, the proportion of imidized anhydride groups is 5%-95%, based on the content of all anhydride groups in the anhydride copolymer being 100%.

[0026] According to some preferred embodiments of the present invention, when the copolymer containing at least one group including anhydride and imide is an imidized product of an anhydride copolymer, the preparation method of the copolymer further includes the step of reacting the anhydride copolymer with ammonia water or ammonia gas first, and then heating to obtain the imidized product.

[0027] According to some preferred embodiments of the present invention, when the anhydride copolymer reacts with ammonia, the reaction time is 30–90 min, the reaction temperature is 70–95 °C, and the molar content of the anhydride groups in the anhydride copolymer is related to NH4. + The molar content is 1:(0.25-2), preferably 1:0.51. As an example, a method for obtaining copolymer microspheres with ammonia water includes: placing the anhydride copolymer microspheres in ammonia water and heating them, wherein the molar content of the anhydride groups in the anhydride copolymer is equal to the molar content of the NH4+ in the ammonia water. + The molar content is 1:0.25-1:2, preferably 1:0.5-1:1, the reaction temperature is 70-95℃, the reaction time with ammonia is preferably 30-90 min, then centrifugation is performed to separate the lower precipitate, and drying is carried out to obtain partially ring-opening copolymer microspheres.

[0028] According to the present invention, when the acid anhydride copolymer is reacted with ammonia to prepare imidized copolymer microspheres, preferably, the acid anhydride copolymer is a copolymer with a cross-linked structure.

[0029] According to some preferred embodiments of the present invention, when the acid anhydride copolymer reacts with ammonia, the acid anhydride copolymer reacts with excess ammonia for a time of 2-10 minutes, as described in CN 112574336A.

[0030] According to some preferred embodiments of the present invention, the heating temperature is 140-180°C and the heating time is 0.5-5 hours.

[0031] According to some preferred embodiments of the present invention, the POE is at least one of ethylene-octene copolymer, ethylene-butene copolymer, and ethylene-hexene copolymer.

[0032] According to some preferred embodiments of the present invention, the POE has a melt index of 3-30 g / 10 min at 190°C and 2.16 kg, and / or the POE has a density of 0.87 g-0.89 g / cm³. 3 .

[0033] According to some preferred embodiments of the present invention, the modified POE composition further comprises additives, preferably including at least one selected from crosslinking agents, co-crosslinking agents, antioxidants, light stabilizers, and silane coupling agents; more preferably,

[0034] In the modified POE composition, by weight, relative to 100 parts of POE, the content of the crosslinking agent is 0.8-1.2 parts, the content of the co-crosslinking agent is 0.4-0.6 parts, the content of the antioxidant is 0.1-0.4 parts, the content of the light stabilizer is 0.1-0.4 parts, and the content of the silane coupling agent is 0.2-0.3 parts. Under this ratio, the modified POE composition is particularly suitable for solar cell encapsulation films.

[0035] The crosslinking agent is selected from commonly used peroxides, the co-crosslinking agent is selected from commonly used co-crosslinking agents in rubber vulcanization, the antioxidant is selected from hindered phenols and / or phosphate esters, the light stabilizer is selected from hindered amines, and the silane coupling agent is selected from the trialkoxy type.

[0036] Generally, increased film haze significantly reduces film transmittance. This invention unexpectedly discovered that the modified POE composition / film of this invention can effectively increase haze with only a slight reduction in transmittance. That is, it can increase film haze while maintaining transmittance. Increasing film haze can increase the conversion efficiency of photovoltaic modules. Therefore, the modified POE composition / film of this invention can increase the conversion efficiency of photovoltaic modules. According to some preferred embodiments of the invention, tested using GB / T 2410-2008, the modified POE composition has a transmittance of ≥74%, preferably ≥86%, in the 380nm-1100nm wavelength range; and / or, a haze of ≥25%; and / or, a transmittance of at least ≤60% in the 200-280nm wavelength range.

[0037] According to some preferred embodiments of the present invention, the modified POE composition absorbs ultraviolet light with wavelengths of 200-280 nm. According to some preferred embodiments of the present invention, the modified POE composition can convert light in the 290-400 nm wavelength band to light in the band above 420 nm. This invention provides a modified POE film with high UV transmittance and improved light conversion efficiency using UV light. The copolymer containing anhydride groups and / or further modified imide groups is responsive to the UV band and exhibits absorption of UV light below 280 nm. Further research, based on literature, reveals that when the carbonyl groups in the anhydride and the modified imide groups are irradiated with UV light, electrons undergo π→π* energy level transitions, converting light from the 290-400 nm band to above 420 nm, exhibiting a fluorescence effect. This further improves the UV resistance and light conversion capability of the POE film. Furthermore, the anhydride groups and their further modified imide groups differ from commonly used UV absorbers and light stabilizers, exhibiting a smaller response to UV light in the 290-380 nm range. Combined with photovoltaic modules that utilize a wider spectral range, this can significantly improve the photoelectric conversion efficiency of photovoltaic modules.

[0038] According to some preferred embodiments of the present invention, the method for preparing the modified POE composition includes blending raw materials including POE, copolymer microspheres containing at least one group including acid anhydride and imide, and optional additives at a melting temperature of the POE and lower than the melting temperature of the copolymer microspheres.

[0039] A second aspect of the present invention is to provide a method for preparing the modified POE composition described in the first aspect, comprising: blending POE, copolymer microspheres containing at least one group including anhydride and imide, and optional additives, under conditions where the melting temperature of the POE is lower than the melting temperature of the copolymer microspheres, to obtain the modified POE composition.

[0040] According to some preferred embodiments of the present invention, the blending method includes one or a combination of mixing, extrusion.

[0041] According to some preferred embodiments of the present invention, the process further includes a step of granulation after blending.

[0042] According to the present invention, the copolymer microspheres are blended at a melting temperature of POE that is lower than the melting temperature of the copolymer microspheres. According to some preferred embodiments of the present invention, the blending temperature is 110-140°C.

[0043] A third aspect of the present invention is to provide a modified POE film comprising the modified POE composition described in the first aspect or the modified POE composition obtained by the preparation method described in the second aspect.

[0044] According to some preferred embodiments of the present invention, the thickness of the modified POE film is 10-300 μm, such as 10 μm, 30 μm, 50 μm, 80 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, and any two values ​​or any range of any two values, preferably 20-150 μm.

[0045] A fourth aspect of the present invention is to provide a method for preparing the modified POE film described in the third aspect, comprising forming the modified POE film by depositing the modified POE composition described in the first aspect or the modified POE composition obtained by the preparation method described in the second aspect.

[0046] According to some preferred embodiments of the present invention, the film-forming steps include hot pressing and casting; more preferably,

[0047] The hot pressing temperature is 110-140℃, and the hot pressing pressure is 0.1-5MPa.

[0048] More preferably, the casting temperature is 110-140℃.

[0049] The fifth aspect of the present invention is to provide the application of the modified POE composition described in the first aspect, the modified POE composition obtained by the preparation method described in the second aspect, the modified POE film described in the third aspect, or the modified POE film obtained by the preparation method described in the fourth aspect, in encapsulation films, preferably in solar cell encapsulation films.

[0050] The modified POE film of this invention can be used as an encapsulating film for solar cells.

[0051] In another preferred embodiment of the present invention, by simply laminating the modified POE film of the present invention with any existing solar cell encapsulation film, an encapsulation film with ultraviolet absorption, ultraviolet light conversion, resistance to additive migration, and high light conversion efficiency can be obtained. Preferably, the modified POE film of the present invention is used in combination with existing encapsulation films to achieve the maximum and most optimized efficiency enhancement for photovoltaic modules.

[0052] When used as an encapsulating film for solar cells, the composite film preferably comprises the following components: i) the modified POE film described in this invention, and ii) an existing solar cell encapsulating film, used together. This invention does not impose specific limitations on existing solar cell encapsulating films. Preferably, this invention is used in conjunction with the modified POE film and the existing solar cell encapsulating film through lamination, with a preferred lamination temperature of 145°C and a lamination time of 20 minutes.

[0053] When the modified POE film of the present invention is used as an encapsulating film for solar cells, it preferably comprises the following components: by weight, based on 100 parts of POE, 0.8-1.2 parts of crosslinking agent, 0.4-0.6 parts of co-crosslinking agent, copolymer microspheres containing at least one group including acid anhydride and imide, 0.1-0.4 parts of antioxidant, 0.1-0.4 parts of light stabilizer, and 0.2-0.3 parts of silane coupling agent. The preferred ratio of copolymer microspheres containing at least one group including acid anhydride and imide to POE is the ratio described above, and will not be repeated here.

[0054] Compared with the prior art, the advantages of the present invention are:

[0055] The modified POE composition and film of the present invention can simultaneously achieve ultraviolet absorption, ultraviolet light conversion, high haze, and improved polarity while maintaining a certain light transmittance. It has ultraviolet absorption and ultraviolet light conversion properties, which can improve the utilization rate of solar energy. It can improve the conversion efficiency of photovoltaic modules by increasing haze while maintaining a certain light transmittance. It can improve the polarity of polar POE composition, which can improve the peel strength of POE to other non-polar materials, and improve the dispersibility of small molecule polar additives in non-polar POE, thereby further improving the performance and lifespan of POE film in practical application scenarios.

[0056] The modified POE film of the present invention has ultraviolet absorption and ultraviolet light conversion properties, as well as resistance to additive migration and high light conversion efficiency.

[0057] The preparation method of the composition obtained by blending in this invention is simpler and has greater potential for widespread application. Attached Figure Description

[0058] Appendix Figure 1The UV absorption diagrams are for modified film 1 (Example 5) and modified film 2 (Example 4).

[0059] Appendix Figure 2 The fluorescence spectrum of the unmodified film (Comparative Example 1) is shown below.

[0060] Appendix Figure 3 The fluorescence spectrum of the modified film (Example 5) is shown.

[0061] Depend on Figure 1 It can be seen that after adding copolymer microspheres containing anhydride and / or imide groups, the UV absorption rate of the modified POE film is 30% to 40% in the wavelength range of 280 nm to 400 nm. When the wavelength range is below 280 nm, the UV absorption of the modified POE film is significantly improved, reaching up to more than 85%. The modified POE film has effective absorption of UV light in the wavelength range below 280 nm.

[0062] Depend on Figure 2 and Figure 3 It can be seen that, compared with the unmodified POE film, the modified POE film with the addition of copolymer microspheres containing anhydride and / or imide groups exhibits a significant light conversion effect, converting light in the 290-400nm band to wavelengths above 420nm. Verification showed that the modified POE films obtained in the other examples could also convert light in the 290-400nm band to wavelengths above 420nm. Detailed Implementation

[0063] The present invention will now be described in detail with reference to specific embodiments. It should be noted that the following embodiments are only used to further illustrate the present invention and should not be construed as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the content of the present invention are still within the scope of protection of the present invention.

[0064] The present invention will be further described with reference to the embodiments. However, the present invention is not limited to these embodiments.

[0065] The experimental data in the examples were obtained using the following instruments and testing methods:

[0066] The transmittance and haze were tested using the Shenguang WGT-S transmittance and haze meter, and the tests were conducted according to the test methods in GB / T2410-2008 "Determination of transmittance and haze of transparent plastics".

[0067] The improvement in POE polarity was characterized by testing the peel strength between POE and aluminum foil. A tensile testing machine was used, and the test was conducted according to the method in GB / T2791-1995 "Adhesives - Test Method for Peel Strength of Flexible Materials to Flexible Materials". The flexible material selected was aluminum foil with a thickness of 0.15 mm. Specifically, the modified POE composition was attached to the aluminum foil by placing an appropriate amount of modified POE composition particles containing anhydride and / or amide (i.e., the modified POE composition) between two 20 cm × 20 cm aluminum foils and hot-pressing them at 120 °C and 1 MPa. The aluminum foil size was 20 cm × 20 cm, and the aluminum foil thickness was 0.1 mm.

[0068] The ultraviolet absorption data were analyzed and tested using a U-3900H ultraviolet spectrophotometer from HITACHI Corporation of Japan, with a wavelength range of 200-800 nm.

[0069] Fluorescence testing was performed on the samples using a JY FL3 fluorescence spectrometer from Horiba Corporation, Japan, with a 450W xenon lamp light source, an excitation wavelength range of 200-650nm, and an emission spectrum range of 300-1000nm.

[0070] The maleic anhydride copolymer microspheres used in the examples were all self-made, and the other raw materials were all commercially available.

[0071] In the following examples, the melt flow index of the POE resin was measured at 190°C and 2.16 kg. The melt flow index of the POE resin was 5 g / 10 min, the melting point was 62°C, and the density was 0.877 g / cm³. 3 Purchased from LG Chem, South Korea; the POE resin has a melt flow index of 30 g / 10 min, a melting point of 60℃, and a density of 0.870 g / cm³. 3 Purchased from Dow Chemical.

[0072] Referring to the published patent CN100579995C, maleic anhydride-styrene copolymer microspheres were prepared with an average particle size of 800 nm. The maleic anhydride-styrene copolymer microspheres are alternating copolymers. The content of maleic anhydride-derived structural units is 50%, based on the total molar content of all structural units in the copolymer being 100%.

[0073] Referring to Example 7 of the published patent CN101338008A, maleic anhydride-styrene crosslinked copolymer microspheres were prepared. The average particle size of the microspheres was 1 μm. The maleic anhydride-styrene copolymer microspheres were alternating copolymers. The content of maleic anhydride-derived structural units was 50%, based on the total molar content of maleic anhydride-derived structural units and styrene-derived structural units in the copolymer being 100%.

[0074] Referring to Example 3 in the published patent CN101580565A, maleic anhydride-α-methylstyrene copolymer microspheres with a particle size of 1 μm were prepared. The maleic anhydride-α-methylstyrene copolymer microspheres are alternating copolymers, and the content of maleic anhydride-derived structural units is 50%, based on the total molar content of all structural units in the copolymer being 100%.

[0075] Maleic anhydride-styrene-isobutylene copolymer microspheres were prepared according to the published patent CN107722177A. The specific preparation method is as follows:

[0076] 6g of isobutylene was passed into a 300mL reactor containing 20g of maleic anhydride, 15g of styrene, 2.4g of azobisisobutyronitrile and 200mL of isoamyl acetate to carry out a free radical copolymerization reaction. The copolymerization reaction pressure was 0.9MPa, the copolymerization reaction temperature was 70℃, and the copolymerization reaction time was 6h.

[0077] The copolymerization product was passed into a flash separator for gas-liquid separation at 25°C and 0 MPa. The resulting liquid-solid mixture was then further separated in a centrifuge at 8000 rpm for 10 min to obtain a solid copolymer powder, which is the maleic anhydride-styrene-isobutylene copolymer microsphere. The maleic anhydride-styrene-isobutylene copolymer microsphere has a particle size of 600 nm. The maleic anhydride-styrene-isobutylene copolymer microsphere is an alternating copolymer, with the content of maleic anhydride-derived structural units being approximately 50%. Based on the total molar content of all structural units in the copolymer being 100%, the molar ratio of styrene-derived structural units to isobutylene-derived structural units is 1:0.5.

[0078] Example 1

[0079] Maleic anhydride-α-methylstyrene copolymer microspheres with a particle size of 1 μm were taken, along with 100 parts by weight of POE resin. The POE resin had a melt index of 5 g / 10 min, a melting point of 62 °C, and a density of 0.877 g / cm³. 3 Add 0.5 parts by weight of maleic anhydride-α-methylstyrene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press at 120°C and 1MPa to form a film with a thickness of 150μm to obtain a modified POE film.

[0080] The modified POE film has a transmittance of 90% and a haze of 35% in the 380nm-1100nm wavelength range, a transmittance of 58% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 6.9mN / mm.

[0081] Example 2

[0082] Maleic anhydride-styrene copolymer microspheres with a particle size of 800 nm were taken, along with 100 parts by weight of POE resin. The POE resin had a melt index of 5 g / 10 min, a melting point of 62 °C, and a density of 0.877 g / cm³. 3 Add 1 part by weight of maleic anhydride-styrene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press it at 120°C and 1MPa to form a film with a thickness of 150μm to obtain a modified POE film.

[0083] The modified POE film has a transmittance of 90% and a haze of 51% in the 380nm-1100nm wavelength range, a transmittance of 53% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 9.3mN / mm.

[0084] Example 3

[0085] Maleic anhydride-styrene-isobutylene copolymer microspheres with a particle size of 600 nm were taken, along with 100 parts by mass of POE resin. The POE resin had a melt index of 5 g / 10 min, a melting point of 62 °C, and a density of 0.877 g / cm³. 3 Add 2 parts by mass of maleic anhydride-styrene-isobutylene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press at 120°C and 1MPa to form a film with a thickness of 120μm to obtain a modified POE film.

[0086] The modified POE film has a transmittance of 89% and a haze of 58% in the 380nm-1100nm wavelength range, a transmittance of 48% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 10.1mN / mm.

[0087] Example 4

[0088] Maleic anhydride-styrene-isobutylene copolymer microspheres with a particle size of 600 nm were taken, along with 100 parts by weight of POE resin. The POE resin had a melt index of 30 g / 10 min, a melting point of 60 °C, and a density of 0.870 g / cm³. 3 Add 5 parts by weight of maleic anhydride-styrene-isobutylene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press at 120°C and 1MPa to form a film with a thickness of 65μm to obtain a modified POE film.

[0089] The modified POE film has a transmittance of 87% and a haze of 82% in the 380nm-1100nm wavelength range, a transmittance of 35% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 12.3mN / mm.

[0090] Example 5

[0091] Maleic anhydride-styrene copolymer microspheres with a particle size of 800 nm were taken, and the surface of the microspheres was continuously purged with ammonia (excess ammonia) for 300 s. The microspheres were then fully reacted in an oven at 180 °C for 3 h to obtain partially imidized maleic anhydride-styrene copolymer microspheres. The proportion of imidized anhydride groups was 90%, based on the content of all anhydride groups in the maleic anhydride-styrene copolymer being 100%.

[0092] Take 100 parts by weight of POE. The POE resin has a melt index of 5 g / 10 min, a melting point of 62℃, and a density of 0.877 g / cm³. 3 Add 1 part by mass of partially imidized maleic anhydride-styrene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press at 120°C and 1MPa to form a film with a thickness of 120μm to obtain a modified POE film.

[0093] The modified POE film has a transmittance of 87% and a haze of 65% in the 380nm-1100nm wavelength range, a transmittance of 49% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 18.6mN / mm.

[0094] Example 6

[0095] Maleic anhydride-α-methylstyrene copolymer microspheres with a particle size of 2 μm, which are alternating copolymers (prepared according to Example 14 of CN101580565A), were taken. 100 parts by weight of POE were also taken. The POE resin had a melt index of 5 g / 10 min, a melting point of 62 °C, and a density of 0.877 g / cm³. 3 Add 0.5 parts by weight of maleic anhydride-α-methylstyrene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press it at 120°C and 1MPa to form a film with a thickness of 150μm to obtain a modified POE film.

[0096] The modified POE film has a transmittance of 88% and a haze of 45% in the 380nm-1100nm wavelength range, a transmittance of 45% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 4.0mN / mm.

[0097] Example 7

[0098] Maleic anhydride-styrene copolymer microspheres with a particle size of 800 nm were taken, along with 100 parts by weight of POE resin. The POE resin had a melt index of 5 g / 10 min, a melting point of 62 °C, and a density of 0.877 g / cm³. 3 Add 20 parts by weight of maleic anhydride-styrene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press it at 120°C and 1MPa to form a film with a thickness of 120μm to obtain a modified POE film.

[0099] The modified POE film has a transmittance of 74% and a haze of 95% in the 380nm-1100nm wavelength range, a transmittance of 10% in the 200-280nm wavelength range, and a peel strength of 21.3mN / mm to aluminum foil.

[0100] Example 8

[0101] Maleic anhydride-styrene copolymer microspheres with a particle size of 800 nm were taken, along with 100 parts by weight of POE resin. The POE resin had a melt index of 5 g / 10 min, a melting point of 62 °C, and a density of 0.877 g / cm³. 3 Add 1 part by weight of maleic anhydride-styrene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press it at 120°C and 1MPa to form a film with a thickness of 300μm to obtain a modified POE film.

[0102] The modified POE film has a transmittance of 84% and a haze of 43% in the 380nm-1100nm wavelength range, a transmittance of 51% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 8.8mN / mm.

[0103] Example 9

[0104] Maleic anhydride-styrene crosslinked copolymer microspheres with a particle size of 1 μm were taken and heated in ammonia water. The molar content of the anhydride groups in the anhydride copolymer was compared with that of NH4 in the ammonia water. + The molar ratio of the ammonia solution was 1:0.75, the reaction temperature was 85℃, and the preferred reaction time with ammonia was 45 min. The mixture was centrifuged to separate the lower precipitate, and then dried in an oven at 180℃ for 3 h to obtain partially imidized maleic anhydride-styrene copolymer microspheres. The proportion of imidized anhydride groups was 20%, based on the assumption that the content of all anhydride groups in the maleic anhydride-styrene copolymer was 100%.

[0105] Take 100 parts by weight of POE. The POE resin has a melt index of 5 g / 10 min, a melting point of 62℃, and a density of 0.877 g / cm³. 3 Add 1 part by mass of partially imidized maleic anhydride-styrene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press at 120°C and 1MPa to form a film with a thickness of 120μm to obtain a modified POE film.

[0106] The modified POE film has a transmittance of 87% and a haze of 62% in the 380nm-1100nm wavelength range, a transmittance of 52% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 7.9mN / mm.

[0107] Example 10

[0108] Itaconic anhydride-styrene copolymer microspheres with a particle size of 600 nm were prepared (refer to Example 2 of CN101979417A, the itaconic anhydride-styrene copolymer microspheres are alternating copolymers).

[0109] Take 100 parts by weight of POE. The POE resin has a melt index of 30 g / 10 min, a melting point of 60℃, and a density of 0.870 g / cm³. 3 Add 5 parts by weight of itaconic anhydride-styrene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press at 120°C and 1MPa to form a film with a thickness of 65μm to obtain a modified POE film.

[0110] The modified POE film has a transmittance of 87% and a haze of 80% in the 380nm-1100nm wavelength range, a transmittance of 38% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 11.5mN / mm.

[0111] Example 11

[0112] Maleic anhydride-α-methylstyrene copolymer microspheres with a particle size of 500 nm were taken. These microspheres are alternating copolymers (prepared according to Example 1 of CN101580565A). 100 parts by weight of POE were also taken. The POE resin has a melt index of 5 g / 10 min, a melting point of 62 °C, and a density of 0.877 g / cm³. 3 Add 0.5 parts by weight of maleic anhydride-α-methylstyrene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press it at 120°C and 1MPa to form a film with a thickness of 150μm to obtain a modified POE film.

[0113] The modified POE film has a transmittance of 90% and a haze of 26% in the 380nm-1100nm wavelength range, a transmittance of 61% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 4.2mN / mm.

[0114] Example 12

[0115] Citric anhydride-styrene copolymer microspheres were prepared according to CN101979417A. The average particle size of the microspheres was 700 nm, and they were alternating copolymers.

[0116] The itaconic anhydride-styrene copolymer microspheres in Example 10 were replaced with citraconic anhydride-styrene copolymer microspheres. The POE film was modified according to Example 10. The performance of the modified POE film was similar to that of Example 10.

[0117] Comparative Example 1

[0118] Take POE resin with a melt flow index of 5 g / 10 min, a melting point of 62℃, and a density of 0.877 g / cm³. 3 The film is granulated by twin-screw extrusion at 120℃ and hot-pressed at 120℃ and 1MPa to form a film with a thickness of 150μm. The transmittance in the 380nm-1100nm band is 89%, the haze is 15%, the transmittance in the 200-280nm band is 86%, and the peel strength to aluminum foil is 2.4mN / mm.

[0119] Comparative Example 2

[0120] Take POE resin with a melt flow index of 30 g / 10 min, a melting point of 60℃, and a density of 0.870 g / cm³. 3 The film is granulated by twin-screw extrusion at 120℃ and hot-pressed at 120℃ and 1MPa to form a film with a thickness of 150μm. The transmittance in the 380nm-1100nm band is 89%, the haze is 18%, the transmittance in the 200-280nm band is 85%, and the peel strength to aluminum foil is 2.2mN / mm.

[0121] Comparative Example 3

[0122] Take 100 parts by weight of POE resin with a melt index of 5 g / 10 min, a melting point of 62℃, and a density of 0.877 g / cm³. 3 Add 0.4 parts by weight each of UV absorber 329 and light stabilizer 508, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press it at 120°C and 1MPa to form a film with a thickness of 150μm to obtain a POE film.

[0123] The POE film has a transmittance of 89% and a haze of 16% in the 380nm-1100nm wavelength range, a transmittance of 10% in the 200-280nm wavelength range, and a peel strength of 2.4mN / mm to aluminum foil.

[0124] Comparative Example 4

[0125] Maleic anhydride-styrene copolymer microspheres with a particle size of 800 nm were taken, along with 100 parts by weight of POE resin. The POE resin had a melt index of 5 g / 10 min, a melting point of 62 °C, and a density of 0.877 g / cm³. 3 Add 0.04 parts by weight of maleic anhydride-styrene copolymer microspheres, granulate by twin-screw extrusion at 120°C to obtain a modified POE composition, and then hot press it at 120°C and 1MPa to form a film with a thickness of 120μm to obtain a modified POE film.

[0126] The modified POE film has a transmittance of 89% and a haze of 10% in the 380nm-1100nm wavelength range, a transmittance of 85% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 2.8mN / mm.

[0127] Comparative Example 5

[0128] Maleic anhydride-styrene copolymer microspheres with a particle size of 800 nm were taken, along with 100 parts by weight of POE resin. The POE resin had a melt index of 5 g / 10 min, a melting point of 62 °C, and a density of 0.877 g / cm³. 3 Add 1 part by mass of maleic anhydride-styrene copolymer microspheres, and granulate by twin-screw extrusion at 260°C (at which temperature the maleic anhydride-styrene copolymer microspheres melt) to obtain a modified POE composition. Then, hot press it at 120°C and 1MPa to form a film with a thickness of 120μm to obtain a modified POE film.

[0129] The modified POE film has a transmittance of 89% and a haze of 12% in the 380nm-1100nm wavelength range, a transmittance of 48% in the 200-280nm wavelength range, and a peel strength to aluminum foil of 9.0mN / mm.

[0130] Detection example

[0131] The modified POE films in each embodiment and comparative example were tested using the method described above for light transmittance in the 380nm-1100nm range, haze in the 380nm-1100nm range, light transmittance in the 200-280nm range, and peel strength with aluminum foil. The specific test results are shown in Table 1.

[0132] Table 1

[0133]

[0134] As can be seen from the comparison of Examples 1-11 and Comparative Examples 1, 2 and 4 in Table 1, when copolymer microspheres containing at least one group including acid anhydride and imide are added to POE, the resulting modified POE composition or film can effectively improve the haze of the modified POE film, achieve ultraviolet absorption in the 200-280nm band, and improve the polarity of POE without significantly affecting the transmittance in the 380nm-1100nm band.

[0135] As can be seen from Examples 1, 2, 3 and Comparative Example 1, by using the method of the present invention, adding maleic anhydride-α-methylstyrene alternating copolymer microspheres, maleic anhydride-styrene alternating copolymer microspheres, and maleic anhydride-styrene-isobutylene alternating copolymer microspheres, the resulting modified POE compositions or films can effectively improve the haze of the modified POE film, the ultraviolet absorption in the 200-280nm band, and the polarity of POE without substantially affecting the transmittance in the 380nm-1100nm band.

[0136] Comparing Examples 3, 4, 7, and 8 with Comparative Examples 1 and 2, it can be seen that for POE matrices with different densities and melt indices, the modified POE film obtained using the method of the present invention shows improvements in haze, UV absorption in the 200-280 nm wavelength range, and polarity. The improvement in polarity is even better with increasing anhydride group content. Comparing Examples 3 and 4, and Examples 7 and 8, it can be seen that by controlling the amount of copolymer microspheres added and the thickness of the modified film, improvements in POE film haze, UV absorption in the 200-280 nm wavelength range, and polarity can still be achieved while maintaining a certain level of light transmittance. Under the preferred modified POE film thickness and the amount of copolymer microspheres containing anhydride or imide groups, the resulting modified POE composition or film exhibits even superior overall performance.

[0137] Comparing Examples 5, 9, and 2 with Comparative Example 1, it can be seen that both modified POE films containing copolymer microspheres with anhydride and imide groups and those containing copolymer microspheres with anhydride groups can effectively improve the haze of the modified POE film, achieve ultraviolet absorption in the 200-280nm band, and improve the polarity of POE, without significantly affecting the transmittance in the 380nm-1100nm wavelength range. When copolymer microspheres containing anhydride and imide groups are added, the resulting modified POE film improves both the haze and polarity of the POE film, and further enhances the ultraviolet absorption in the 200-280nm wavelength range.

[0138] Comparing Examples 6, 11, and 1 with Comparative Example 1, it can be seen that the particle size of the added copolymer microspheres affects the balance between the transmittance and haze of the modified POE film. Reducing the particle size will reduce the haze of the POE film, while increasing the particle size will reduce the transmittance of the POE film in the 380nm-1100nm range. Using the method of the present invention, the haze of the modified POE film can be effectively improved while maintaining the transmittance in the 380nm-1100nm band. Under the preferred copolymer microsphere particle size of the present invention, the obtained modified POE film has even better overall performance.

[0139] As shown in Comparative Example 4, although commercially available UV absorbers and light stabilizers can effectively absorb UV light in the 200-280nm wavelength range, they cannot improve the haze and polarity of the POE film. A comparison of Examples 1-11 with Comparative Example 4 shows that the modified POE film of this invention can significantly improve the haze and polarity of the POE film.

[0140] As shown in Comparative Example 5, when the added copolymer containing anhydride and / or imide groups does not exist in the form of microspheres, it does not provide any beneficial improvement to the haze of the POE film. As shown in Examples 1-11 and Comparative Example 5, the modified POE film containing copolymer microspheres containing anhydride and / or imide groups in this invention exhibits significantly improved haze, and its transmittance in the 380nm-1100nm wavelength range, transmittance in the 200-280nm range, and polarity also remain at high levels, achieving unexpected technical effects.

[0141] It should be noted that the embodiments described above are only for explaining the present invention and do not constitute any limitation on the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory terms, not limiting terms. Modifications can be made to the present invention within the scope of the claims, and revisions can be made to the present invention without departing from the scope and spirit of the present invention. Although the present invention described herein relates to specific methods, materials, and embodiments, it does not mean that the present invention is limited to the specific examples disclosed herein; on the contrary, the present invention can be extended to all other methods and applications with the same function.

[0142] All publications, patent applications, patents, and other references mentioned in this specification are incorporated herein by reference. Unless otherwise defined, all technical and scientific terms used in this specification have the meanings commonly understood by those skilled in the art. In case of conflict, the definitions in this specification shall prevail.

[0143] When this specification uses the prefixes “known to those skilled in the art,” “prior art,” or similar terms to derive materials, substances, methods, steps, apparatus, or components, the objects derived from such prefixes cover those commonly used in the art at the time of this application, but also include those that are not currently commonly used but will become generally recognized in the art as suitable for similar purposes.

[0144] The endpoints and any values ​​of the ranges disclosed in this application are not limited to the precise ranges or values; such ranges or values ​​should be understood to include values ​​close to them. For numerical ranges, the endpoint values ​​of the various ranges, the endpoint values ​​of the various ranges and individual point values, and individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed herein. In principle, various technical solutions can be combined with each other to obtain new technical solutions, which should also be considered as specifically disclosed herein.

[0145] In the context of this specification, except where expressly stated otherwise, any matters or issues not mentioned shall apply directly to those known in the art without any modification.

[0146] Furthermore, any implementation described herein can be freely combined with one or more other implementations described herein, and the resulting technical solutions or technical ideas shall be regarded as part of the original disclosure or original record of the present invention, and should not be regarded as new content not disclosed or anticipated herein, unless those skilled in the art consider the combination to be obviously unreasonable.

Claims

1. A modified POE composition comprising POE and copolymer microspheres containing at least one group including anhydride and imide, wherein the copolymer is a carbon chain polymer; The mass ratio of the copolymer microspheres to POE is (0.05-20):

100.

2. The modified POE composition according to claim 1, characterized in that: The copolymer containing at least one group, including anhydride and imide, has a mass ratio of POE of (0.1-10):100, preferably (0.5-5):

100.

3. The modified POE composition according to claim 1, characterized in that: The copolymer containing at least one group, including anhydride and imide, is an anhydride copolymer and / or an imidized product of an anhydride copolymer; and / or, The average particle size of the copolymer microspheres is 400 nm-3 μm, preferably 500 nm-2 μm, and more preferably 600 nm-1 μm.

4. The modified POE composition according to claim 3, characterized in that: The anhydride copolymer contains structural units derived from monomers containing anhydride groups and structural units derived from one or more monomers containing isolated carbon-carbon double bonds; more preferably, The content of the anhydride groups is 20%-80%, preferably 30%-70%, more preferably 40%-60%, based on the total molar content of all structural units in the anhydride copolymer being 100%; More preferably, the anhydride copolymer has a structure in which monomers containing anhydride groups are copolymerized alternately with monomers containing isolated carbon-carbon double bonds.

5. The modified POE composition according to claim 4, characterized in that: The monomer containing an anhydride group contains an anhydride group and an isolated carbon-carbon double bond, and is preferably selected from at least one of maleic anhydride, itaconic anhydride, and citraconic anhydride; and / or, The monomer containing an isolated carbon-carbon double bond is selected from at least one of C2-C9 olefins, C4 fractions, C5 fractions, C8 fractions, C9 fractions, and vinyl acetate; preferably at least one of styrene, α-methylstyrene, isobutylene, C4 fractions, and C8 fractions; and / or, The anhydride copolymer was obtained by copolymerization via self-stabilizing precipitation polymerization.

6. The modified POE composition according to claim 4, characterized in that: When a copolymer containing at least one group, including anhydride and imide, is an imidized product of an anhydride copolymer, the proportion of imidized anhydride groups is 5%-95%, based on the assumption that the content of all anhydride groups in the anhydride copolymer is 100%; preferably, When the copolymer containing at least one group, including anhydride and imide, is an imidized product of an anhydride copolymer, the preparation method of the copolymer further includes the step of reacting the anhydride copolymer with ammonia water or ammonia gas, followed by heating to obtain the imidized product; more preferably, When the acid anhydride copolymer reacts with ammonia, the reaction time is 30–90 min, the reaction temperature is 70–95 °C, and the molar content of the acid anhydride groups in the acid anhydride copolymer is related to NH4. + The molar content is 1:(0.25-2); and / or, more preferably, When the acid anhydride copolymer reacts with ammonia, the acid anhydride copolymer reacts with excess ammonia for 2-10 minutes; and / or, More preferably, the heating temperature is 140-180°C and the heating time is 0.5-5 hours.

7. The modified POE composition according to claim 1, characterized in that: The POE is at least one of ethylene-octene copolymer, ethylene-butene copolymer, and ethylene-hexene copolymer; and / or, The POE has a melt flow index of 3-30 g / 10 min at 190℃ and 2.16 kg, and / or the POE has a density of 0.87 g-0.89 g / cm³. 3 .

8. The modified POE composition according to claim 1, characterized in that: The modified POE composition also contains additives. Preferably, the additives include at least one selected from crosslinking agents, co-crosslinking agents, antioxidants, light stabilizers, and silane coupling agents; more preferably, In the modified POE composition: by mass, relative to 100 parts of POE, the content of the crosslinking agent is 0.8-1.2 parts, the content of the co-crosslinking agent is 0.4-0.6 parts, the content of the antioxidant is 0.1-0.4 parts, the content of the light stabilizer is 0.1-0.4 parts, and the content of the silane coupling agent is 0.2-0.3 parts.

9. The modified POE composition according to any one of claims 1-8, characterized in that: According to GB / T 2410-2008, the modified POE composition has a transmittance of ≥74% in the 380nm-1100nm band, preferably ≥86%, and / or a haze of ≥25%, and / or a transmittance of ≤60% in the 200-280nm band. And / or, the modified POE composition absorbs ultraviolet light with a wavelength of 200-280 nm; And / or, the modified POE composition is capable of converting light in the 290-400nm band to light in the band above 420nm; Preferably, the method for preparing the modified POE composition includes blending raw materials including POE, copolymer microspheres containing at least one group including acid anhydride and imide, and optional additives at a melting temperature of the POE and lower than the melting temperature of the copolymer microspheres.

10. A method for preparing a modified POE composition according to any one of claims 1-9, comprising: The modified POE composition is obtained by blending raw materials including POE, copolymer microspheres containing at least one group including acid anhydride and imide, and optional additives at a melting temperature of the POE and lower than that of the copolymer microspheres. Preferably, the blending method includes one or a combination of mixing and extrusion; and / or, Preferably, the blending temperature is 110-140℃.

11. A modified POE film, said modified POE film comprising the modified POE composition according to any one of claims 1-9 or the modified POE composition obtained by the preparation method according to claim 10; preferably, The thickness of the modified POE film is 10-300 μm, preferably 20-150 μm.

12. A method for preparing the modified POE film according to claim 11, comprising forming the modified POE film by forming the modified POE composition according to any one of claims 1-9 or the modified POE composition obtained by the preparation method according to claim 10; Preferably, the film-forming steps include hot pressing and casting; more preferably, The hot pressing temperature is 110-140℃, and the hot pressing pressure is 0.1-5MPa; and / or, the casting temperature is 110-140℃.

13. The use of a modified POE composition according to any one of claims 1-9, or a modified POE composition obtained by the preparation method according to claim 10, or a modified POE film according to claim 11, or a modified POE film obtained by the preparation method according to claim 12, in encapsulation films, preferably in solar cell encapsulation films.

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