Light conversion agent and preparation method thereof, light conversion adhesive film and photovoltaic module

Abstract

The invention belongs to the technical field of light conversion agents for photovoltaic adhesive films, and particularly relates to a light conversion agent and a preparation method thereof, a light conversion adhesive film and a photovoltaic module. According to the light conversion agent and the preparation method thereof, the light conversion adhesive film and the photovoltaic module, on the basis of an existing triazole light conversion agent, the defect that an N-substituted triazole light conversion agent is not resistant to migration is overcome, silane / siloxane is introduced and can interact with matrix resin to form an interpenetrating network structure, a stable intermolecular bonding bridge of a network polysiloxane structure is formed, and the migration resistance of the N-substituted triazole light conversion agent is improved. The light conversion agent and the matrix resin are combined in a chemical bond form, so that the dissociation of small molecules of the light conversion agent is reduced, and the migration of the light conversion agent is effectively improved.

Description

Technical Field

[0001] The invention belongs to the technical field of light conversion agents for photovoltaic adhesive films, and specifically relates to a light conversion agent and a preparation method thereof, a light conversion adhesive film, and a photovoltaic module. Background Art

[0002] Since the packaging material of solar cells is a polymer material, high-energy rays such as ultraviolet rays in the atmosphere have a certain destructive effect on the carbon chain of the material. Therefore, in order to reduce the degradation and aging effects of ultraviolet light in sunlight on EVA film, light stabilizers and ultraviolet absorbers are usually added to the material. Among them, light stabilizers can shield or absorb the energy of ultraviolet light in EVA film, quench singlet oxygen and decompose hydroperoxides into inactive substances, thereby reducing and delaying the aging of EVA resin. Ultraviolet light absorbers can selectively absorb high-energy ultraviolet light and release and consume the absorbed energy in the form of energy conversion as heat energy or harmless low-energy radiation, thereby avoiding the chemical reaction of aging and degradation of EVA resin due to the absorption of ultraviolet light energy.

[0003] In order to better utilize solar energy, light conversion agents are usually used to convert ultraviolet light that cannot be absorbed by the solar cell into visible light. However, the existing organic light conversion agents are prone to migration in the film due to their small molecular polarity differences. The N-substituted triazole light conversion agents have few coupling active sites, which is not conducive to the modification of their migration resistance.

[0004] Therefore, how to overcome the difficulties of the existing mainstream N-position modified triazole light conversion agents and the difficulty of migration resistance modification is a technical problem that needs to be solved urgently in this field.

[0005] It should be noted that the above information disclosed in this background technology section is only used to understand the background technology of the present application concept, and therefore, the above description is not considered to constitute information of the prior art. Summary of the invention

[0006] The embodiments of the present disclosure at least provide a light conversion agent and a preparation method thereof, and a light conversion adhesive film.

[0007] In a first aspect, the present disclosure provides a light conversion agent, the general structural formula of the light conversion agent is as follows:

[0008] Where R0 is -(CH2) n -Si(R a )3; R a It is any one of an alkyl group and an alkoxy group having one to six carbon atoms; and n is an integer of 0 to 5.

[0009] In an optional embodiment, the R aThe alkyl group includes any one of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl and n-hexyl.

[0010] In an optional embodiment, the structural formula of the light conversion agent is:

[0011]

[0012] In an optional embodiment, the structural formula of the light conversion agent is:

[0013]

[0014] In an optional embodiment, the R a The alkoxy group includes any one of methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy and acetoxy.

[0015] In an optional embodiment, the structural formula of the light conversion agent is:

[0016]

[0017] In an optional embodiment, R0 on both sides of the light conversion agent is an asymmetric structure.

[0018] In an optional embodiment, the structural formula of the light conversion agent is:

[0019]

[0020] In a second aspect, the embodiments of the present disclosure further provide a method for preparing the light conversion agent as described above, comprising the following steps: step S1, reacting benzotriazole with isobutyl iodide, and separating by column to obtain 1-isobutyl benzotriazole and 2-isobutyl benzotriazole; step S21, reacting 2-isobutyl benzotriazole with sufficient liquid bromine to obtain 2-isobutyl-4,7-dibromobenzotriazole; step S22, reacting 2-isobutyl benzotriazole with about 1.1 molar amounts of liquid bromine to obtain 2-isobutyl-4-bromobenzotriazole; step S3 1. 2-isobutyl-4,7-dibromobenzotriazole and a phenylboronic acid compound with an R0 group are synthesized to obtain a light conversion agent with a symmetrical structure; step S32, 2-isobutyl-4-bromobenzotriazole and a phenylboronic acid compound with an R0 group are synthesized to obtain an intermediate; step S42, the intermediate is reacted with about 1.1 parts by mole of liquid bromine, and then synthesized with a phenylboronic acid compound with an R0 group to obtain a light conversion agent with an asymmetrical structure; wherein the structure of the R0 group carried by the phenylboronic acid compound with an R0 group in step S32 and step S42 is different.

[0021] In a third aspect, the embodiments of the present disclosure also provide a light conversion adhesive film, comprising the following components in parts by weight: 90-100 parts of a base resin, 0.2-1.5 parts of a cross-linking agent, 0.1-3 parts of a co-cross-linking agent, 0.1-1 parts of a light stabilizer, 0.01-0.3 parts of an antioxidant, 0.2-1 parts of a coupling agent, and 0.1-1 parts of a light conversion agent as described in any one of claims 1 to 8.

[0022] In a fourth aspect, the embodiments of the present disclosure further provide a photovoltaic module, comprising the light conversion adhesive film as described above.

[0023] The beneficial effect of the present invention is that, based on the existing triazole light conversion agent, the present light conversion agent and its preparation method, the light conversion adhesive film, and the photovoltaic module overcome the defect that the N-substituted triazole light conversion agent is not resistant to migration. By introducing silane / siloxane, it can interact with the matrix resin to form an interpenetrating network structure, forming a stable network polysiloxane structure molecular "bonding bridge", combining the light conversion agent and the matrix resin in the form of chemical bonds, reducing the free small molecules of the light conversion agent, and effectively improving the migration of the light conversion agent.

[0024] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention are realized and obtained by the structures particularly pointed out in the description, claims and drawings.

[0025] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 The nuclear magnetic hydrogen spectrum of the light conversion agent of Example 1 provided in the embodiments of the present disclosure;

[0028] Figure 2 The H NMR spectrum of the light conversion agent of Example 2 provided in the embodiments of the present disclosure;

[0029] Figure 3 This is the H NMR spectrum of the light conversion agent of Example 3 provided in the embodiments of the present disclosure.

[0030] Figure 4This is the H NMR spectrum of the light conversion agent of Example 4 provided in the embodiments of the present disclosure. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. 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.

[0032] As used herein, the phrases "in one embodiment," "according to one embodiment," "in some embodiments," and the like generally refer to the fact that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present disclosure. Therefore, a particular feature, structure, or characteristic may be included in more than one embodiment of the present disclosure, so that these phrases do not necessarily refer to the same embodiment. As used herein, the terms "example," "exemplary," and the like are used to "serve as an example, instance, or illustration." Any implementation, aspect, or design described herein as "example" or "exemplary" is not necessarily to be construed as preferred or superior to other implementations, aspects, or designs. On the contrary, the use of the terms "example," "exemplary," and the like is intended to present concepts in a concrete manner.

[0033] Herein, example embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. As used herein, expressions such as "at least one of..." modify the entire list of elements when following a list of elements, rather than modifying individual elements in the list. For example, the expression "at least one of a, b, and c" should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b, and c.

[0034] The terms used herein are only used to describe specific exemplary configurations and are not intended to be limited. As used herein, the singular articles "one", "an" and "the" may also be intended to include plural forms, unless it is clearly indicated above that this is not the case. The terms "comprise", "include" and "have" are inclusive, and therefore specify the presence of features, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components and / or combinations thereof. The method steps, processes and operations described herein should not be interpreted as necessarily requiring them to be performed in the specific order discussed or shown, unless specifically identified as an execution order. Additional or alternative steps may be adopted.

[0035] The removal of N-modified triazoles is not conducive to migration resistance modification. Due to the resonance effect of triazole itself, the N substitution probability of different positions of N-substituted triazole light conversion agents is consistent, and the yield is greatly affected. For the light conversion rate of triazole modification, the product yield is also one of the important determining factors.

[0036] The defects existing in the above solutions are the results obtained by the inventor after practice and careful research. Therefore, the discovery process of the above problems and the solutions proposed by the present disclosure for the above problems below should be the contributions made by the inventor to the present disclosure during the disclosure process.

[0037] The present disclosure provides a light conversion agent, the general structural formula of which is as follows:

[0038] Where R0 is -(CH2) n -Si(R a )3; R a It is any one of an alkyl group and an alkoxy group having one to six carbon atoms; and n is an integer of 0 to 5.

[0039] In some embodiments, specifically, R a The alkyl group includes any one of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl and n-hexyl.

[0040] In some embodiments, specifically, the light conversion agent has the structural formula:

[0041]

[0042] In some embodiments, specifically, the light conversion agent has the structural formula:

[0043]

[0044] In some embodiments, specifically, R a The alkoxy group includes any one of methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy and acetoxy.

[0045] In some embodiments, specifically, the light conversion agent has the structural formula:

[0046]

[0047] In some embodiments, specifically, R0 on both sides of the light conversion agent is an asymmetric structure, where the asymmetric structure is compared with the symmetric structure of R0 on both sides in some of the aforementioned embodiments, and does not mean that R0 on one side itself is a symmetric or asymmetric structure.

[0048] In some embodiments, specifically, the light conversion agent has the structural formula:

[0049]

[0050] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0051] The synthesis of 2-isobutylbenzotriazole, the chemical formula is as follows:

[0052]

[0053] Benzotriazole (6.078g, 50.000mmol, w=98%), isobutyl iodide (11.382g, 60mmol, w=97%), potassium carbonate (20.732g, 150.000mmol, w=99%), added to a round-bottom flask, dissolved with DMF (100mL), and heated under condensation reflux at 80°C for 5h until the raw material point completely disappeared (cannot be stirred at room temperature, benzotriazole easily turns into HOBt and the reaction fails). After the reaction is completed, DMF is washed away with saturated ammonium chloride solution, extracted with ethyl acetate 5 times, dried with sodium sulfate and the solvent is evaporated. Silica gel is used as the stationary phase, and the organic solvent (DCM:PE=1:4) is separated by column to obtain: 1-isobutylbenzotriazole (4.105g, separation yield 47%) and 2-isobutylbenzotriazole (4.100g, separation yield: 47%).

[0054] The synthesis of 2-isobutyl-4,7-dibromobenzotriazole, the chemical formula is as follows:

[0055]

[0056] 2-isobutylbenzotriazole (4.100 g, 23.398 mmol), hydrobromic acid (28.468 g, 168.887 mmol, w = 48%), liquid bromine (11.217 g, 70.194 mmol), were added to a round-bottom flask in sequence, refluxed at 130 ° C for 24 h, washed with potassium hydroxide in ice water to remove the hydrobromic acid and liquid bromine in the reaction, extracted with DCM 5 times, dried with anhydrous sodium sulfate and the solvent was dried by spin drying. Column separation: 2-isobutyl-4,7-dibromobenzotriazole (7.170 g, separation yield: 92%).

[0057] Embodiment 1 Synthesis of light conversion agent, chemical formula is as follows:

[0058]

[0059] Take 2-isobutyl-4,7-dibromobenzotriazole (0.468g, 1.406mmol), 4-(trimethylsilyl)phenylboronic acid (0.767g, 3.937mmol, w=98%), potassium carbonate (0.585g, 4.218mmol, w=99%), tetrakistriphenylphosphine palladium (0.163g, 0.141mmol). First, add all the solids into the reaction vessel, evacuate the air, fill with nitrogen, use 1,4-dioxane (5mL) to dissolve 2-isobutyl-4,7-dibromobenzotriazole and inject it into the reactor with a syringe. In addition, water (1mL) needs to be injected into the reactor with a syringe. In a sealed reactor, reflux at 100°C for 12h until 2-isobutyl-4,7-dibromobenzotriazole reacts completely. After the reaction is completed, the reaction solution is poured into a beaker, and water is absorbed with anhydrous sodium sulfate and filtered, and the solvent is dried by spin drying. Silica gel is used as the stationary phase, and an organic solvent (DCM:PE=1:10) is used as the mobile phase. The column is separated and recrystallized to obtain Figure 1 The H NMR spectrum of the light converting agent of Example 1 (0.230 g, isolated yield: 35%) is shown.

[0060] Embodiment 2 Synthesis of light conversion agent, chemical formula is as follows:

[0061]

[0062] Take 2-isobutyl-4,7-dibromobenzotriazole (0.468g, 1.406mmol), 4-(trimethoxysilane)phenylboronic acid (1.133g, 3.937mmol, w=98%), potassium carbonate (0.586g, 4.230mmol, w=99%), tetrakistriphenylphosphine palladium (0.163g, 0.141mmol). First, add all the solids into the reaction vessel, evacuate the air, fill with nitrogen, use 1,4-dioxane (5mL) to dissolve 2-isobutyl-4,7-dibromobenzotriazole and inject it into the reactor with a syringe. In addition, water (1mL) needs to be injected into the reactor with a syringe. In a sealed reactor, reflux at 100°C for 12h until 2-isobutyl-4,7-dibromobenzotriazole reacts completely. After the reaction is completed, the reaction solution is poured into a beaker, and water is absorbed with anhydrous sodium sulfate and filtered, and the solvent is dried by spin drying. Silica gel is used as the stationary phase, and an organic solvent (DCM:PE=1:10) is used as the mobile phase. The column is separated and recrystallized to obtain Figure 2 The H NMR spectrum of the light converting agent of Example 2 (0.245 g, isolated yield: 38%) is shown.

[0063] Embodiment 3 Synthesis of light conversion agent, the chemical formula is as follows:

[0064]

[0065] Take 2-isobutyl-4,7-dibromobenzotriazole (0.468g, 1.420mmol), 4-(tert-butyldimethylsilyloxy)phenylboronic acid (1.002g, 3.976mmol, w=98%), potassium carbonate (0.589g, 4.260mmol, w=99%), tetrakistriphenylphosphine palladium (0.164g, 0.142mmol). First, add all the solids into the reaction vessel, evacuate the air, fill with nitrogen, use 1,4-dioxane (5mL) to dissolve 2-isobutyl-4,7-dibromobenzotriazole and inject it into the reactor with a syringe. In addition, water (1mL) needs to be injected into the reactor with a syringe. In a sealed reactor, reflux at 100°C for 12h until 2-isobutyl-4,7-dibromobenzotriazole reacts completely. After the reaction is completed, the reaction solution is poured into a beaker, water is absorbed with anhydrous sodium sulfate and filtered, and the solvent is dried by spin drying. Silica gel is used as the stationary phase, and an organic solvent (DCM:PE=1:5) is used as the mobile phase. The column is separated to obtain Figure 3 The H NMR spectrum of the light converting agent of Example 3 (0.542 g, isolated yield: 65%) is shown.

[0066] The synthesis of 2-isobutyl-4-bromobenzotriazole, the chemical formula is as follows:

[0067]

[0068] 2-isobutylbenzotriazole (3.088 g, 17.623 mmol), hydrobromic acid (10.292 g, 127.208 mmol, w = 48%), liquid bromine (3.098 g, 19.385 mmol), were added to a round-bottom flask in sequence, refluxed at 100 ° C for 24 h, the hydrobromic acid and liquid bromine in the reaction were washed off with icy potassium hydroxide solution, extracted with DCM 5 times, dried with anhydrous sodium sulfate and the solvent was dried by spin drying. Column separation: 2-isobutyl-4-bromobenzotriazole (2.463 g, separation yield: 55%).

[0069] The synthesis of 2-isobutyl-4-(4-tert-butylphenyl)benzotriazole has the following chemical formula:

[0070]

[0071] Take 2-isobutyl-4-bromobenzotriazole (0.985g, 3.880mmol), 4-tert-butylphenylboronic acid (1.057g, 5.820mmol, w=98%), potassium carbonate (1.608g, 11.640mmol, w=99%), tetrakistriphenylphosphine palladium (0.448g, 0.388mmol). First, add all the solids to the reaction vessel, evacuate the air, fill with nitrogen, dissolve 2-isobutyl-4-bromobenzotriazole with 1,4-dioxane (5mL), and inject it into the reactor with a syringe. In addition, water (1mL) needs to be injected into the reactor with a syringe. Reflux at 100°C for 12h until 2-isobutyl-4-bromobenzotriazole reacts completely. After the reaction is completed, pour the reaction solution into a beaker, absorb water with anhydrous sodium sulfate and filter, and spin dry the solvent. Silica gel was used as the stationary phase and an organic solvent (DCM:PE=1:10) was used as the mobile phase to separate 2-isobutyl-4-(4-tert-butylphenyl)benzotriazole (0.891 g, separation yield: 74%).

[0072] The synthesis of 2-isobutyl-4-(4-tert-butylphenyl)-7-bromobenzotriazole has the following chemical formula:

[0073]

[0074] 2-isobutyl-4-(4-tert-butylphenyl)benzotriazole (0.315 g, 1.024 mmol), hydrobromic acid (1.246 g, 7.392 mmol, w=48%), and liquid bromine (0.160 g, 1.000 mmol) were added to a round-bottom flask in sequence, refluxed at 100°C for 18 h, and the hydrobromic acid and liquid bromine in the reaction were washed off with an icy potassium hydroxide solution, extracted with DCM 5 times, dried with anhydrous sodium sulfate, and the solvent was dried by spin drying. Column separation: 2-isobutyl-4-(4-tert-butylphenyl)-7-bromobenzotriazole (0.245 g, separation yield: 63%).

[0075] Embodiment 4 Synthesis of light conversion agent, chemical formula is as follows:

[0076]

[0077] Take 2-isobutyl-4-(4-tert-butylphenyl)-7-bromobenzotriazole (0.270g, 0.700mmol), 4-(trimethylsilyl)phenylboronic acid (0.208g, 1.050mmol, w=98%), potassium carbonate (0.290g, 2.100mmol, w=99%), tetrakistriphenylphosphine palladium (0.081g, 0.070mmol). First, add all the solids into the reaction vessel, evacuate the air, fill with nitrogen, use a syringe to extract 1,4-dioxane (5mL) and water (1mL) and inject them into a sealed reactor, reflux at 100°C for 12h until 2-isobutyl-4-(4-tert-butylphenyl)-7-bromobenzotriazole reacts completely. After the reaction is completed, pour the reaction solution into a beaker, absorb water with anhydrous sodium sulfate and filter, and spin dry the solvent. Silica gel was used as the stationary phase and organic solvent (EA:PE = 1:20) was used as the mobile phase. The column was separated to obtain the following Figure 4 The H NMR spectrum of the light converting agent of Example 4 (0.281 g, isolated yield: 88%) is shown.

[0078] In some embodiments, specifically, 100 parts of EVA resin DuPont 53071, 0.5 parts of cross-linking agent 2-ethylhexyl carbonate tert-butyl peroxide, 0.5 parts of co-cross-linking agent triallyl isocyanurate, 0.2 parts of light stabilizer light stabilizer 770, 0.1 parts of antioxidant hindered phenol antioxidant 1010, 0.3 parts of coupling agent silane coupling agent KH-570, and several parts of light conversion agent are blended with each component, granulated at 160-220°C to obtain grafted EVA resin, and cast co-extruded to obtain light conversion film. The specific weight proportion of light conversion agent is shown in Table 1 below.

[0079] Table 1

[0080] Example Add Scale Comparative Example 1 0.15 parts of benzotriazole Comparative Example 2 0.15 parts of N-modified benzotriazole Example 1 0.15 parts of the light conversion agent of Example 1 Example 2 0.15 parts of the light conversion agent of Example 2 Example 3 0.15 parts of the light conversion agent of Example 3 Example 4 0.15 parts of the light conversion agent of Example 4

[0081] The performance of the light-converting adhesive film prepared in the embodiment was further measured, and the test performance was as follows:

[0082] The film sample of 30*30cm was laminated with the battery cell into a single piece, and the migration distance of the light conversion agent from the front to the back was evaluated after baking at 105℃ for 48h, 120h, 192h, and 264h (unit / cm). The specific migration distance is shown in Table 2 below.

[0083] Table 2

[0084] 48h 120h 192h 264h Comparative Example 1 4 5 6 8 Comparative Example 2 3 4 5 6 Example 1 1 1 3 3 Example 2 1 1 2 3 Example 3 1 2 2 4 Example 4 1 2 3 3

[0085] In summary, the light conversion agent and its preparation method, light conversion adhesive film, and photovoltaic module, based on the existing triazole light conversion agent, overcome the defect of N-substituted triazole light conversion agent that is not resistant to migration. By introducing silane / siloxane, it can interact with the matrix resin to form an interpenetrating network structure, forming a stable network polysiloxane structure molecular "bonding bridge", combining the light conversion agent and the matrix resin in the form of chemical bonds, reducing the free small molecules of the light conversion agent, and effectively improving the migration of the light conversion agent.

[0086] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A light conversion agent, characterized in that: The general structural formula of the light conversion agent is as follows: in R0 is -(CH2) n -Si(R a )3; R a Any one of an alkyl group and an alkoxy group having one to six carbon atoms; n is an integer from 0 to 5.

2. The light conversion agent according to claim 1, characterized in that The R a The alkyl group includes any one of methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, n-pentyl, isopentyl, neopentyl and n-hexyl.

3. The light conversion agent according to claim 2, characterized in that The structural formula of the light conversion agent is:

4. The light conversion agent according to claim 2, characterized in that The structural formula of the light conversion agent is:

5. The light conversion agent according to claim 1, characterized in that The R a The alkoxy group includes any one of methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy and acetoxy.

6. The light conversion agent according to claim 5, characterized in that The structural formula of the light conversion agent is:

7. The light conversion agent according to claim 1, characterized in that The R0 on both sides of the light conversion agent is an asymmetric structure.

8. The light conversion agent according to claim 7, characterized in that The structural formula of the light conversion agent is:

9. A method for preparing the light conversion agent according to claim 1, characterized in that: The steps include: Step S1, reacting benzotriazole with isobutyl iodide, and separating by column to obtain 1-isobutylbenzotriazole and 2-isobutylbenzotriazole; Step S21, reacting 2-isobutylbenzotriazole with sufficient liquid bromine to obtain 2-isobutyl-4,7-dibromobenzotriazole; Step S22, reacting 2-isobutylbenzotriazole with about 1.1 molar amounts of liquid bromine to obtain 2-isobutyl-4-bromobenzotriazole; Step S31, synthesizing 2-isobutyl-4,7-dibromobenzotriazole and a phenylboronic acid compound having an R0 group to obtain a light conversion agent with a symmetrical structure; Step S32, synthesizing 2-isobutyl-4-bromobenzotriazole and a phenylboronic acid compound having an R0 group to obtain an intermediate; Step S42, reacting the intermediate with about 1.1 molar amounts of liquid bromine, and then synthesizing with a phenylboronic acid compound having an R0 group to obtain an asymmetric light conversion agent; in The structure of the R0 group carried by the phenylboronic acid compound carrying the R0 group in step S32 and step S42 is different.

10. A light-converting adhesive film, characterized in that: The composition includes the following components in parts by weight: 90-100 parts of base resin, 0.2-1.5 parts of crosslinking agent, 0.1-3 parts of auxiliary crosslinking agent, 0.1-1 parts of light stabilizer, 0.01-0.3 parts of antioxidant, 0.2-1 parts of coupling agent, and 0.1-1 parts of the light conversion agent according to any one of claims 1-8.

11. A photovoltaic module, characterized in that: It comprises the light-converting adhesive film as described in claim 10.

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