Liquid benzotriazole photoluminescent material

Abstract

The invention discloses a liquid benzotriazole photoluminescence material, which is composed of a mixture of long-chain alkyl substituted 4, 7-diphenyl benzotriazole compounds with different carbon atom numbers or different carbon chain configurations or different substitution positions or different substitution numbers. The flexible long-chain alkyl substituent is adopted, so that the photoluminescent material has better dispersity in an adhesive film, and the prepared adhesive film shows excellent light transmittance. The liquid benzotriazole photoluminescent material disclosed by the invention is not easy to aggregate or crystallize, so that the problem that the light conversion agent is separated out in the use process of the adhesive film is avoided, and the light conversion adhesive film has a longer period of validity. The product is in a liquid state and can be dissolved in a liquid auxiliary agent in the adhesive film preparation process, and compared with the prior art that the material is in a crystalline solid state, is difficult to dissolve and is difficult to uniformly disperse in the processing process, the product is more convenient to use, and the processing process is greatly simplified.

Description

Technical Field

[0001] The invention belongs to the technical field of luminescent materials, and in particular relates to a liquid benzotriazole photoluminescent material. Background Art

[0002] The power generation efficiency of photovoltaic modules is one of the most critical indicators of solar energy utilization. At present, n-type modules such as TOPCon modules and heterojunction (HJT) modules are becoming the mainstream development trend of photovoltaic modules due to their high power generation efficiency (>25%). However, according to research reports, ultraviolet rays can destroy the silicon-hydrogen bonds in the passivation layer of heterojunction (HJT) modules and cause the decline of module efficiency (Sol.RRL 2023,7,2300334; Prog Photovolt ResAppl.2023,31,36). The US Renewable Energy Testing Center (RETC) reported that TOPCon modules are also facing the risk of ultraviolet radiation-induced degradation (UVID). In order to avoid the impact of ultraviolet radiation on battery modules, the use of UV-blocking films containing ultraviolet absorbers is a reliable technical means. However, this method undoubtedly wastes energy in the ultraviolet band and causes a certain loss in the power generation efficiency of the module.

[0003] Light transfer film can convert ultraviolet rays into visible light with longer wavelengths. While shielding harmful ultraviolet rays, the converted visible light can be effectively utilized by the components. It is an effective technical means to solve the problem of ultraviolet-induced power attenuation in n-type photovoltaic modules. The main component of light transfer film is down-conversion luminescent material, among which benzotriazole organic luminescent materials are widely used in the preparation of solar cell light transfer film due to their high luminous efficiency and excellent stability (CN105419380B, CN103562323B, CN117510421B, CN117431022A).

[0004] The preparation of light transfer film is usually obtained by dispersing the luminescent material in the EVA or POE film during the melt heat processing. However, the existing benzotriazole luminescent materials are usually crystalline solids, so it is difficult to achieve uniform dispersion during the film preparation process, which brings inconvenience to processing and use. Moreover, the crystalline benzotriazole luminescent material is easy to precipitate in the EVA or POE film, resulting in the light transfer film being prone to increased haze, decreased transmittance and light conversion efficiency decline caused by aggregation after a period of use, resulting in a shortened service life. This not only affects the efficiency of solar cells, but also limits the application of light transfer films in the field of photovoltaic power generation. Summary of the invention

[0005] To solve the above technical problems, the present invention provides a liquid long-chain alkyl-substituted benzotriazole-based photoluminescent material, which is easy to disperse in a film and not prone to crystallization, avoiding aggregation and precipitation, and greatly improving the effective service life of the light conversion film.

[0006] To avoid crystallization and aggregation of the material, creatively, the present invention designs a mixture composed of 4,7-diphenylbenzotriazole compounds substituted by long-chain alkyl groups with different carbon atom numbers, different carbon chain structures, different substitution positions, or different substitution base numbers. Due to the weakened interaction between different configuration carbon chain structures, the stacking between molecules is effectively prevented, the crystallinity of the material becomes poor, and it can be in a liquid state (easy to flow and disperse at room temperature or slightly heated state).

[0007] Specifically, the technical solution of the present invention is as follows:

[0008] A liquid benzotriazole-based photoluminescent material, wherein the photoluminescent material is a mixture composed of 4,7-diphenylbenzotriazole compounds substituted by long-chain alkyl groups with different structures. The long-chain alkyl group refers to a straight-chain or branched-chain alkyl group with 7 to 18 carbon atoms. The structure of the 4,7-diphenylbenzotriazole compound substituted by the long-chain alkyl group is shown in Formula I:

[0009]

[0010] In Formula I, R a ~R e and R h ~R l are each independently a hydrogen atom or a C1-C18 alkyl group, and at least one of the groups R a ~R e is a straight-chain or branched-chain alkyl group with 7 to 18 carbon atoms, and at least one of the groups R h ~R l is a straight-chain or branched-chain alkyl group with 7 to 18 carbon atoms; A is a C1-C18 alkyl group or a derivative of a C1-C18 alkyl group. The derivative of the C1-C18 alkyl group refers to a functional group with a molecular weight within 400 formed by substituting the C1-C18 alkyl group with an ether group, an ester group, a hydroxyl group, a mercapto group, a carboxyl group, a halogen, a cyano group, an amino group, an amide group, a C1-C6 alkenyl group, a C1-C6 alkynyl group, a C1-C6 alkyl group, a halogenated C1-C6 alkyl group, a C1-C6 alkoxy group, an aryl group, a heteroaryl group, and a combination of these groups;

[0011] The 4,7-diphenylbenzotriazole compound substituted by the long-chain alkyl group is according to R a ~R e and R h ~R lClassify the structure of the long-chain alkyl group. As long as the number of carbon atoms, carbon chain configuration, substitution position, and substitution number of the long-chain alkyl group are the same, and the other substituents except the long-chain alkyl group and the A substituent can be the same or different, they are all regarded as one long-chain alkyl substitution component;

[0012] The mixture contains six or more different structures of long-chain alkyl substitution components. The molar fraction of any long-chain alkyl substitution component does not exceed 30%, and the sum of the molar fractions of the top three long-chain alkyl substitution components does not exceed 70%, the sum of the molar fractions of the top four long-chain alkyl substitution components does not exceed 85%, and the sum of the molar fractions of the top five long-chain alkyl substitution components does not exceed 95%;

[0013] The mixture is highly disordered and exhibits a liquid state at room temperature.

[0014] Examples of C7-C18 straight-chain or branched-chain alkyl groups are n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-octadecyl, 2-ethylhexyl, isooctyl, tert-octyl, tert-octyl, branched-chain dodecyl, branched-chain hexadecyl, etc.

[0015] Preferably, the structure of the long-chain alkyl-substituted 4,7-diphenylbenzotriazole compound is shown in Formula II:

[0016]

[0017] In Formula II, represents that there is an R 1 and R 2 substituent at any position on the benzene ring; R 1 and R 2 are each independently a C7-C18 straight-chain or branched-chain alkyl group; A is a C1-C18 alkyl group or a derivative of a C1-C18 alkyl group. The derivative of the C1-C18 alkyl group refers to a functional group with a molecular weight within 400 formed by substituting the C1-C18 alkyl group with an ether group, an ester group, a hydroxyl group, a mercapto group, a carboxyl group, a halogen, a cyano group, an amino group, an amide group, a C1-C6 alkenyl group, a C1-C6 alkynyl group, a C1-C6 alkyl group, a halogenated C1-C6 alkyl group, a C1-C6 alkoxy group, an aryl group, a heteroaryl group, and a combination of these groups;

[0018] The long-chain alkyl-substituted 4,7-diphenylbenzotriazole compound is classified according to the structure of the long-chain alkyl R 1 and R 2 . As long as the number of carbon atoms, carbon chain configuration, and substitution position of the long-chain alkyl group are the same, and the A substituent can be the same or different, they are all regarded as one long-chain alkyl substitution component;

[0019] The mixture contains six or more long-chain alkyl-substituted components with different structures. The molar fraction of any long-chain alkyl-substituted component does not exceed 30%, and the sum of the molar fractions of the top three long-chain alkyl-substituted components does not exceed 70%, the sum of the molar fractions of the top four long-chain alkyl-substituted components does not exceed 85%, and the sum of the molar fractions of the top five long-chain alkyl-substituted components does not exceed 95%.

[0020] The mixture is highly disordered and exhibits a liquid state at room temperature.

[0021] Number and proportion of long-chain alkyl-substituted structural components

[0022] C7-C18 long-chain alkyl substitution makes the 4,7-diphenylbenzotriazole compound more flexible, increasing its solubility and dispersibility. The present invention finds that when a mixture is formed by using multiple long-chain alkyl-substituted components with different structures in the system, due to the difficulty of forming a completely ordered packing structure between different alkyl groups, the overall packing effect between molecules is significantly weakened, it is difficult to form a long-range ordered structure, and the melting point of the material is significantly reduced.

[0023] In the technical solution of the present invention, the mixture contains six or more long-chain alkyl-substituted components. The molar fraction of any long-chain alkyl-substituted component does not exceed 30%, and the sum of the molar fractions of the top three long-chain alkyl-substituted components does not exceed 70%, the sum of the molar fractions of the top four long-chain alkyl-substituted components does not exceed 85%, and the sum of the molar fractions of the top five long-chain alkyl-substituted components does not exceed 95%. Such a design ensures that the proportions of six or more components are relatively dispersed, it is difficult to form an effective packing between long-chain alkyls, the material is highly disordered microscopically and cannot form a locally crystalline state, and macroscopically it exhibits a liquid state.

[0024] As a counterexample, when the proportion of a certain long-chain alkyl-substituted component in the mixture is very high, such as reaching more than 40-50%, the intermolecular packing effect of the compound is enhanced, showing an amorphous solid or even a locally crystalline state. When the number of mixture components is small, such as only 3 to 4 components, it is also impossible to achieve high disorder, and the material shows an amorphous solid.

[0025] Selection of A substituent

[0026] Regarding the selection of the A substituent, preferably, in the 4,7-diphenylbenzotriazole compound, A is selected from C1-C18 alkyl or substituted C1-C18 alkyl, and the substitution means substitution by an ether group, an ester group, a hydroxyl group, a carboxyl group, an amide group, a C1-C6 alkyl group, a C1-C6 alkenyl group, a C1-C6 alkoxy group, a phenyl group and a combination thereof.

[0027] Particularly preferably, the 4,7-diphenylbenzotriazole compounds are selected from the structures shown in Formulae III-a to III-l, IV-a to IV-f, and V-a to V-f:

[0028]

[0029]

[0030]

[0031] In Formulae III-a to III-l, IV-a to IV-f, and V-a to V-f, R 1 and R 2 are each independently a straight-chain or branched-chain alkyl group having 7 to 18 carbon atoms; in Formulae V-a to V-f, X is a straight-chain or branched-chain C1-C18 alkylene group.

[0032] Preparation method and component proportion probability

[0033] The liquid benzotriazole-based photoluminescent material of the present invention can be obtained by mixing six or more single components in a designed ratio, or can be directly prepared by cross-coupling reaction of a variety of [long-chain alkyl-substituted phenyl derivative active substrates] with different structures according to the designed feeding ratio; or the mixture obtained by cross-coupling can be mixed with a single-structured component in a ratio, or a variety of mixtures obtained by cross-coupling can be mixed in a ratio.

[0034] Preferably, the liquid benzotriazole-based photoluminescent material is prepared by cross-coupling reaction of one (or more) [2-A-yl-4,7-dibromobenzotriazole] shown in Formula M with three or more [long-chain alkyl-substituted phenyl derivative active substrates] shown in Formula N with different structures, and the reaction equation is as shown in Formula a:

[0035]

[0036] In Formula a, …… represents phenyl derivatives shown in Formula b with different structures; in Formula b, R a to R e are each independently a hydrogen atom or a C1-C18 alkyl group, and at least one is a C7-C18 straight-chain or branched-chain alkyl group;

[0037] A is a C1-C18 alkyl group or a derivative of a C1-C18 alkyl group; Z represents an active group capable of undergoing a catalytic coupling reaction, and the active group is selected from a boronic acid group, a boronic acid ester group, a magnesium bromide Grignard reagent, a magnesium chloride Grignard reagent, a magnesium iodide Grignard reagent, and a trifluoromethanesulfonate;

[0038] In the preparation method, among the [long-chain alkyl-substituted phenyl derivative active substrates] of formula N with three or more different structures, the molar fraction of the [long-chain alkyl-substituted phenyl derivative active substrate] ranked first does not exceed 40%, the molar fraction of the [long-chain alkyl-substituted phenyl derivative active substrate] ranked second does not exceed 35%, and the molar fraction of the [long-chain alkyl-substituted phenyl derivative active substrate] ranked third does not exceed 34%.

[0039] Regarding the influence of the molar fraction of the [long-chain alkyl-substituted benzene derivative active substrate] structural type on the compound structure distribution in the final product, the present invention is described as follows.

[0040] Each molecule of the 4,7-diphenylbenzotriazole compound is obtained by the coupling reaction of one molecule of [2-A group-4,7-dibromobenzotriazole] with two molecules of [long-chain alkyl-substituted phenyl derivative active substrate]. The coupling reaction is carried out in two steps. (1) In the first step, one molecule of [2-A group-4,7-dibromobenzotriazole] reacts with one molecule of [long-chain alkyl-substituted phenyl derivative active substrate] to obtain a mono-coupled product. (2) In the second step, the mono-coupled product further couples with the second molecule of [long-chain alkyl-substituted phenyl derivative active substrate] to generate a double-coupled product, that is, the 4,7-diphenylbenzotriazole compound. The coupling reaction is carried out according to the feed ratio, and the obtained product also has a corresponding ratio according to the probability distribution.

[0041] (1)

[0042] (2)

[0043] For example, the molar fraction of the a-component [long-chain alkyl-substituted phenyl derivative active substrate] in the feed ratio is A, the molar fraction of the b-component [long-chain alkyl-substituted phenyl derivative active substrate] in the feed ratio is B, the molar fraction of the c-component [long-chain alkyl-substituted phenyl derivative active substrate] in the feed ratio is C...

[0044] In the first-step mono-coupling reaction, the probability of the a-component [long-chain alkylbenzene] (abbreviated as the a-component) participating in the reaction is A, the probability of the b-component [long-chain alkylbenzene] (abbreviated as the b-component) participating in the reaction is B, the probability of the c-component [long-chain alkylbenzene] (abbreviated as the c-component) participating in the reaction is C...; in the second-step double-coupling reaction, the probability of the a-component participating in the reaction is A, the probability of the b-component participating in the reaction is B, the probability of the c-component participating in the reaction is C...

[0045] Among the 4,7-diphenylbenzotriazole compounds produced by the coupling, according to whether the structures of the two [long-chain alkylbenzenes] are the same, it is divided into single-structure coupling and different-structure cross-coupling.

[0046] Single - structure coupling: The product with the first - step single - coupling being component a and the second - step double - coupling also being component a is labeled as a - a, with a probability of A * A; the product with the first - step single - coupling being component b and the second - step double - coupling also being component b is labeled as b - b, with a probability of B * B; the product with the first - step single - coupling being component c and the second - step double - coupling also being component c is labeled as c - c, with a probability of C * C;

[0047] Different - structure cross - coupling: The product with the first - step single - coupling being component a and the second - step double - coupling being component b is labeled as a - b, with a probability of A * B; the product with the first - step single - coupling being component b and the second - step double - coupling being component a is labeled as b - a, with a probability of B * A; since the structures of a - b and b - a are the same and both are labeled as a - b, the total probability is 2A * B. Similarly, the probability of the coupling product containing component a and component c is 2A * C, and the probability of the coupling product containing component b and component c is 2B * C...

[0048]

[0049]

[0050] Example 1. For example, in a preferred preparation method of the present invention, a certain liquid light - emitting material is obtained by cross - coupling reaction of [2 - A - group - 4,7 - dibromobenzotriazole] with [long - chain alkyl - substituted phenyl derivative active substrates] of three different structures. Among them, the molar fraction of component a [long - chain alkyl - substituted phenyl derivative active substrate] is 40%, the molar fraction of component b is 35%, and the molar fraction of component c is 25%. Then the theoretical contents of each component in the obtained mixture are shown in the following table:

[0051]

[0052] The proportion of a - a coupling product is 40% * 40% = 16%, the proportion of b - b coupling product is 35% * 35% = 12.25%, and the proportion of c - c coupling product is 25% * 25% = 6.25%; the proportion of a - b coupling product is 2 * 40% * 35% = 28%, the proportion of a - c coupling product is 2 * 40% * 25% = 20%, and the proportion of b - c coupling product is 2 * 35% * 25% = 17.5%; the sum of the proportions is 16% + 12.25% + 6.25% + 28% + 20% + 17.5% = 100%.

[0053] In the obtained mixture, the coupling product with the highest proportion is a - b coupling product at 28%, followed by a - c coupling product at 20%, then b - c coupling product at 17.5%, and then in turn are a - a coupling product at 16%, b - b coupling product at 12.25%, and c - c coupling product at 6.25%.

[0054] Example 2. In another example, a certain liquid light-emitting material is obtained by cross-coupling reaction of [2-A group-4,7-dibromobenzotriazole] with [long-chain alkyl-substituted phenyl derivative active substrates] having three different structures. Among them, the molar fraction of component a [long-chain alkyl-substituted phenyl derivative active substrate] is 40%, the molar fraction of component b is 30%, and the molar fraction of component c is 30%. Then the theoretical content of each component in the resulting mixture is shown in the following table:

[0055]

[0056] The proportion of a-a coupling product is 40% * 40% = 16%, the proportion of b-b coupling product is 30% * 30% = 9%, and the proportion of c-c coupling product is 30% * 30% = 9%; the proportion of a-b coupling product is 2 * 40% * 30% = 24%, the proportion of a-c coupling product is 2 * 40% * 30% = 24%, and the proportion of b-c coupling product is 2 * 30% * 30% = 18%; the total proportion is 16% + 9% + 9% + 24% + 24% + 18% = 100%.

[0057] In the resulting mixture, the highest proportions are 24% for a-b coupling product and 24% for a-c coupling product, followed by 18% for b-c coupling product, then 16% for a-a coupling product, 9% for b-b coupling product, and 9% for c-c coupling product in sequence.

[0058] Example 3. In another example, a certain liquid light-emitting material is obtained by cross-coupling reaction of [2-A group-4,7-dibromobenzotriazole] with [long-chain alkyl-substituted phenyl derivative active substrates] having three different structures. Among them, the molar fraction of component a [long-chain alkyl-substituted phenyl derivative active substrate] is 35%, the molar fraction of component b is 35%, and the molar fraction of component c is 30%. Then the theoretical content of each component in the resulting mixture is shown in the following table:

[0059]

[0060] The proportion of a-a coupling product is 35% * 35% = 12.25%, the proportion of b-b coupling product is 35% * 35% = 12.25%, and the proportion of c-c coupling product is 30% * 30% = 9%; the proportion of a-b coupling product is 2 * 35% * 35% = 24.5%, the proportion of a-c coupling product is 2 * 35% * 30% = 21%, and the proportion of b-c coupling product is 2 * 35% * 30% = 21%; the total proportion is 12.5% + 12.5% + 9% + 24.5% + 21% + 21% = 100%.

[0061] In the resulting mixture, the a-b coupling product has the highest proportion at 24.5%, followed by the a-c coupling product at 21%, the b-c coupling product at 21%, and then in sequence the a-a coupling product at 12.25%, the b-b coupling product at 12.25%, and the c-c coupling product at 9%.

[0062] Example 4. In another example, a certain liquid light-emitting material is obtained by cross-coupling reaction of [2-A group-4,7-dibromobenzotriazole] with [long-chain alkyl-substituted phenyl derivative active substrates] having three different structures. Among them, the molar fraction of component a [long-chain alkyl-substituted phenyl derivative active substrate] accounts for The molar fraction of component b The molar fraction of component c Then the theoretical contents of each component in the resulting mixture are shown in the following table:

[0063]

[0064]

[0065] The proportion of the a-a coupling product is The proportion of the b-b coupling product is The proportion of the c-c coupling product is The proportion of the a-b coupling product is The proportion of the a-c coupling product is The proportion of the b-c coupling product is The total proportion is

[0066] In the resulting mixture, the a-b coupling product has the highest proportion The a-c coupling product The b-c coupling product Subsequently, it is the a-a coupling product The b-b coupling product The c-c coupling product

[0067] Example 5. In another example, a certain liquid light-emitting material is obtained by cross-coupling reaction of [2-A group-4,7-dibromobenzotriazole] with [long-chain alkyl-substituted phenyl derivative active substrates] having four different structures. Among them, the molar fraction of component a [long-chain alkyl-substituted phenyl derivative active substrate] accounts for 40%, the molar fraction of component b accounts for 30%, the molar fraction of component c accounts for 20%, and the molar fraction of component d accounts for 10%. Then the theoretical contents of each component in the resulting mixture are shown in the following table:

[0068]

[0069]

[0070] The proportion of a-a coupling product is 40% * 40% = 16%, the proportion of b-b coupling product is 30% * 30% = 9%, the proportion of c-c coupling product is 20% * 20% = 4%, and the proportion of d-d coupling product is 10% * 10% = 1%; the proportion of a-b coupling product is 2 * 40% * 30% = 24%, the proportion of a-c coupling product is 2 * 40% * 20% = 16%, the proportion of a-d coupling product is 2 * 40% * 10% = 8%, the proportion of b-c coupling product is 2 * 30% * 20% = 12%, the proportion of b-d coupling product is 2 * 30% * 10% = 6%, and the proportion of c-d coupling product is 2 * 20% * 10% = 4%; the total proportion is 16% + 9% + 4% + 1% + 24% + 16% + 8% + 12% + 6% + 4% = 100%.

[0071] In the obtained mixture, the highest proportion is 24% of a-b coupling product, followed by 16% of a-c coupling product, 16% of a-a coupling product, then 12% of b-c coupling product, and then in turn 9% of b-b coupling product, 8% of a-d coupling product, 6% of b-d coupling product, 4% of c-d coupling product, 4% of c-c coupling product, and 1% of d-d coupling product.

[0072] According to the preferred manufacturing method of the present invention, the raw materials are fed in proportion, {the molar fraction ratios of the top three [long-chain alkyl-substituted phenyl derivative active substrates] do not exceed 40%, 35%, 34%}, and the finally prepared product contains six or more components, the distribution ratios of each component are dispersed, the highest component ratio does not exceed 30%, and the sum of the molar fractions of the top three long-chain alkyl-substituted components does not exceed 70%, the sum of the molar fractions of the top four long-chain alkyl-substituted components does not exceed 85%, and the sum of the molar fractions of the top five long-chain alkyl-substituted components does not exceed 95%; the obtained product is highly disordered microscopically and shows a liquid state.

[0073] Direct preparation of liquid luminescent material mixture by "one-pot method"

[0074] The present invention provides a preparation method of a liquid benzotriazole-based photoluminescent material, which is characterized in that the preparation method is as shown in reaction equation a. One or more [2-A group-4,7-dibromobenzotriazole] represented by formula M and three or more different structures of [long-chain alkyl-substituted phenyl derivative active substrates] represented by formula N, after adding a solvent and a catalyst, through a catalytic coupling reaction, directly obtain a mixture composed of a variety of different structures of [4,7-diphenylbenzotriazole] by "one-pot method";

[0075] In the preparation method, among the [long-chain alkyl-substituted phenyl derivative active substrates] with three or more different structures, the molar fraction of the [long-chain alkyl-substituted phenyl derivative active substrate] ranked first does not exceed 40%, the molar fraction of the [long-chain alkyl-substituted phenyl derivative active substrate] ranked second does not exceed 35%, and the molar fraction of the [long-chain alkyl-substituted phenyl derivative active substrate] ranked third does not exceed 34%.

[0076] A is a C1-C18 alkyl group or a derivative of a C1-C18 alkyl group; Z represents an active group that can undergo a catalytic coupling reaction, and the active group is selected from a boronic acid group, a boronic acid ester group, a magnesium bromide Grignard reagent, a magnesium chloride Grignard reagent, a magnesium iodide Grignard reagent, and a trifluoromethanesulfonate.

[0077] Preferably, in the preparation method, the solvent for the reaction is selected from one or more mixtures of diethyl ether, tetrahydrofuran, dioxane, and toluene; the catalyst for the reaction is selected from a nickel catalyst and a palladium catalyst; the reaction temperature is from room temperature to the reflux temperature.

[0078] The preparation method of the liquid benzotriazole-based photoluminescent material of the present invention has the advantages of simplicity and easy availability. A mixture of various long-chain alkyl-substituted 4,7-diphenylbenzotriazole compounds with different structures is directly obtained by a one-pot method, and the purified product is in a liquid state. If only the [2-A-group-4,7-dibromobenzotriazole] shown in formula M with a single structure and the [long-chain alkylbenzene active substrate] shown in formula N are used in the preparation process, then only a benzotriazole-based photocompound with a single structure can be obtained. Although a mixture of various single-structure long-chain alkyl-substituted benzotriazole photocompounds can also be used to obtain the liquid photoluminescent material of the present invention, the preparation process is quite complex.

[0079] A composite formulation material of a liquid luminescent material and a small amount of a structure with short-chain alkyl substitution

[0080] The present invention provides a composite material (composite formulation material) composed of a long-chain alkyl-substituted liquid benzotriazole-based photoluminescent material and a non-long-chain alkyl-substituted solid benzotriazole-based luminescent compound. The composite formulation material includes the long-chain alkyl-substituted liquid benzotriazole-based photoluminescent material and one or more non-long-chain alkyl-substituted 4,7-diphenylbenzotriazole-based luminescent compounds with a molar fraction not exceeding 10%; the structure of the non-long-chain alkyl-substituted 4,7-diphenylbenzotriazole-based luminescent compound is as shown in formula I:

[0081]

[0082] Among them, R a ~R e 、Rh ~R l Each is independently selected from a hydrogen atom and a C1-C6 alkyl group; A is a C1-C18 alkyl group or a derivative of a C1-C18 alkyl group. The derivative of the C1-C18 alkyl group refers to a functional group with a molecular weight within 400 formed by substituting the C1-C18 alkyl group with an ether group, an ester group, a hydroxyl group, a mercapto group, a carboxyl group, a halogen, a cyano group, an amino group, an amide group, a C1-C6 alkenyl group, a C1-C6 alkynyl group, a C1-C6 alkyl group, a halogenated C1-C6 alkyl group, a C1-C6 alkoxy group, an aryl group, a heteroaryl group, and a combined group thereof;

[0083] Preferably, in the material of the composite formulation, R of the short-chain alkyl-substituted solid benzotriazole compound a ~R e 、R h ~R l Each is independently selected from a hydrogen atom and a C3-C6 alkyl group.

[0084] In the liquid benzotriazole-based photoluminescent material, when the molar ratio of the short-chain alkyl-substituted or unsubstituted 4,7-diphenylbenzotriazole compound does not exceed 10%, it can be uniformly dispersed in the system (both are 4,7-diphenylbenzotriazole structures, and the intermolecular interactions are similar), without affecting the overall state of the material, and thus no crystallization will precipitate.

[0085] When the molar ratio of the short-chain alkyl-substituted or unsubstituted 4,7-diphenylbenzotriazole compound reaches 15-20% or more, a precipitation tendency gradually forms, especially local precipitation will occur during long-term storage.

[0086] Preferably, the molar fraction of the short-chain alkyl-substituted or unsubstituted 4,7-diphenylbenzotriazole compound in the mixture is less than 5%.

[0087] After the mixture of the composite formulation is heated, the short-chain alkyl-substituted solid benzotriazole compound dissolves and disperses in the long-chain alkyl-substituted liquid benzotriazole-based photoluminescent material to obtain a material of the composite formulation with a final liquid state.

[0088] The material of the composite formulation also has a final liquid state and has the same application effect as the liquid benzotriazole-based photoluminescent material.

[0089] During the process of preparing a mixture of long-chain alkyl-substituted liquid benzotriazole compounds by the "one-pot method", adding less than 10% of [short-chain alkyl phenyl derivative active substrate] can also prepare a mixture of liquid benzotriazole compounds containing a small amount of short-chain alkyls, which is also within the protection scope of the present invention.

[0090] Material with a composite formulation of a liquid luminescent material, a liquid auxiliary agent, and a readily soluble solid auxiliary agent

[0091] The present invention provides a composite material (material with a composite formulation) of a liquid benzotriazole-based photoluminescent material, a liquid auxiliary agent, and a readily soluble solid auxiliary agent. The liquid auxiliary agent and the readily soluble solid auxiliary agent are selected from peroxide crosslinking agents, silane coupling agents, crosslinking aids, light stabilizers, antioxidants, ultraviolet absorbers, and other inert auxiliary agents that do not affect the film formulation;

[0092] The mass ratio of the liquid benzotriazole-based photoluminescent material is x, the mass ratio of the liquid auxiliary agent is y, and the mass ratio of the readily soluble solid auxiliary agent is z, where 20 w / w% ≤ x < 100 w / w%, 0 w / w% < y ≤ 80 w / w%, 0 w / w% ≤ z ≤ 20 w / w%, and x + y + z = 100 w / w%.

[0093] Preferably, the proportion of the readily soluble solid auxiliary agent is 0 w / w%.

[0094] The peroxide crosslinking agent, silane coupling agent, crosslinking aid, light stabilizer, antioxidant, and ultraviolet absorber are all common types of auxiliary agents in the preparation of light conversion films. The material with a composite formulation of the liquid benzotriazole-based photoluminescent material, the liquid auxiliary agent, and the readily soluble solid auxiliary agent is used to prepare a light conversion film without side effects and can achieve the same use effect as the liquid benzotriazole-based photoluminescent material.

[0095] Examples of the other inert auxiliary agents that do not affect the film formulation include liquid plasticizers, white oil, nano calcium carbonate, nano titanium dioxide, etc.

[0096] Polymer complex

[0097] The present invention also provides a polymer complex with a light conversion function. The polymer complex contains an optically transparent polymer matrix and the above-mentioned liquid or colloidal benzotriazole-based photoluminescent material.

[0098] Preferably, in the polymer complex with a light conversion function, the liquid benzotriazole-based photoluminescent material is present in the polymer matrix in an amount of 0.01 - 5 wt%. Further preferably, the content of the liquid benzotriazole-based photoluminescent material is 0.05 - 0.5 wt%. If the content of the luminescent material is less than 0.01%, the light conversion effect will be not obvious. The high-concentration case is suitable for the preparation of light conversion masterbatch, which can be further diluted to prepare a light conversion film.

[0099] For the case where the materials of the composite formula of liquid benzotriazole-based photoluminescent materials, liquid additives, and easily soluble solid additives are dispersed in a polymer composite, only the proportion of the liquid benzotriazole-based photoluminescent materials in the polymer is calculated. For example, if a composite formula material is formed by mixing a liquid photoluminescent material and a liquid silane coupling agent in a ratio of 1:1, and the proportion of the composite formula material in the polymer is 0.4 w / w%, then the effective proportion of the liquid benzotriazole-based photoluminescent material in the polymer composite is 0.2 w / w%.

[0100] For the case where the materials of the composite formula composed of long-chain alkyl-substituted liquid benzotriazole-based photoluminescent materials and a small amount of non-long-chain alkyl-substituted solid benzotriazole-based luminescent compounds are dispersed in a polymer composite, the proportions of all components are calculated. For example, a composite formula material composed of a long-chain alkyl-substituted liquid benzotriazole-based photoluminescent material (90%) and a small amount of non-long-chain alkyl-substituted solid benzotriazole-based luminescent compound (10%), adding 1% in the film means containing 0.9% of the long-chain alkyl-substituted liquid benzotriazole-based photoluminescent material and 0.1% of the non-long-chain alkyl-substituted solid benzotriazole-based luminescent compound.

[0101] Preferably, in the polymer composite with the light conversion function, the polymer matrix is selected from polyethylene terephthalate, polyacrylate, polymethyl methacrylate, polyvinyl butyral, ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), ethylene-tetrafluoroethylene copolymer, polyimide, amorphous polycarbonate, polystyrene, silicone sol-gel, polyurethane, and combinations thereof; more preferably, the polymer matrix is selected from polymethyl methacrylate, polyvinyl butyral, ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), ethylene-tetrafluoroethylene copolymer, silicone sol-gel, and combinations thereof; particularly preferably, the polymer matrix is selected from ethylene-vinyl acetate copolymer (EVA) and polyolefin elastomer (POE).

[0102] Application effect

[0103] The liquid benzotriazole-based photoluminescent material of the present invention has better dispersibility in the film of materials such as EVA or POE by using long-chain alkyl substitution of C7-C18. In particular, the present invention uses a mixture of 4,7-diphenylbenzotriazole compounds substituted with long-chain alkyls of different structures, and it is difficult to form effective stacking between different alkyl chains, thus avoiding the aggregation of triazole-based luminescent materials. The prepared film exhibits excellent light transmittance, and there is no loss of light transmittance caused by the scattering of any precipitated particles. Even after long-term placement or use, the film will not have the problem of fogging caused by the precipitation of additives.

[0104] The benzotriazole-based photoluminescent material of the present invention is in a liquid state that is easily flowable at room temperature or under slightly heated conditions (less than 80 °C). This property enables it to be easily dissolved in added liquid auxiliaries (such as silane coupling agents, peroxide crosslinking agents, crosslinking aids) during the preparation of the adhesive film or directly mixed with resin particles. Compared with the problems in the prior art where solid materials are difficult to dissolve and difficult to disperse evenly in resin particles, the treatment method of the present invention is more convenient, greatly simplifying the processing and use processes.

[0105] The benzotriazole-based photoluminescent material of the present invention has high luminous efficiency and excellent stability. These properties enable the prepared light-converting adhesive film to effectively absorb ultraviolet light and convert it into visible light (blue-violet light). While protecting the photovoltaic module, it can effectively improve the power generation efficiency of solar cells, and is expected to promote the development of the photovoltaic power generation field.

[0106] Remarks

[0107] "Aryl" in the present invention refers to an aromatic group, including but not limited to phenyl, naphthyl, phenanthryl, perylenyl, fluorenyl, pyrenyl, etc. "Heteroaryl" refers to an aromatic group containing one or more heteroatoms, including but not limited to pyridyl, pyrrolyl, furyl, thienyl, quinolinyl, isoquinolinyl, quinoxalinyl, benzofuranyl, benzothienyl, indolyl, benzoxazolyl, benzothiazolyl, benzoxazinyl, etc.

[0108] The "liquid luminescent material" described in the present invention means that the material is in a flowable liquid state at room temperature, or in a viscous colloidal state at room temperature and can become a completely flowable liquid when heated to about 80 °C. Brief Description of the Drawings

[0109] Figure 1 is the 1 H NMR spectrum of the luminescent material P1 in Example 1 of the present invention.

[0110] Figure 2 is the excitation and emission spectra of the 1# adhesive film in Example 16 of the present invention.

[0111] Figure 3 is the luminescence quantum efficiency spectrum of the 1# adhesive film in Example 16 of the present invention. Detailed Description of the Invention

[0112] The following further illustrates the products, preparation methods and applications of the present invention through specific examples, but these specific implementation schemes do not limit the protection scope of the present invention in any way.

[0113] The preparation method of the benzotriazole-based photoluminescent material of the present invention is carried out by reacting an intermediate M [2-A-yl-4,7-dibromobenzotriazole] (A represents a substituent at the 2-position of benzotriazole, which is an alkyl or substituted alkyl) with an [alkylbenzene active substrate] (abbreviated as R a -Ph-Z, R a represents an alkyl group, Ph represents a phenyl group, and Z represents an active group that can undergo a catalytic coupling reaction). After adding a solvent and a catalyst, a [4,7-bis(long-chain alkylphenyl)-benzotriazole] - type luminescent material is obtained through a catalytic coupling reaction.

[0114] The liquid benzotriazole-based photoluminescent material described in the present invention can be obtained by mixing six or more single components in a designed ratio, or can be directly prepared by cross-coupling reaction of [long-chain alkyl-substituted phenyl derivative active substrates] with various different structures according to the designed feeding ratio; or the mixture obtained by cross-coupling can be mixed with a single structural component in proportion, or mixtures obtained by multiple cross-couplings can be mixed in proportion.

[0115] Preferably, the liquid benzotriazole-based photoluminescent material is prepared by cross-coupling reaction of one (or more) [2-A-yl-4,7-dibromobenzotriazole] represented by formula M with three or more different structures of [long-chain alkyl-substituted phenyl derivative active substrates].

[0116] Preparation of intermediate M.

[0117]

[0118] In the first step S1, [2-A-ylbenzotriazole] is obtained by reacting benzotriazole with a haloalkane (A-X); in the second step S2, intermediate M [2-A-yl-4,7-dibromobenzotriazole] is obtained by bromination reaction of [2-A-ylbenzotriazole] with bromine; where X is a halogen (fluorine, chlorine, bromine, iodine), and A is a C1-C18 alkane or alkane derivative.

[0119] Intermediate M1.

[0120]

[0121] S1. Mix benzotriazole (35.7 g, 0.3 mol), potassium carbonate (124.5 g, 0.9 mol) and N,N-dimethylformamide (DMF, 300 mL), heat to 80 °C, and dropwise add bromobutane (49.2 g, 0.36 mol, exothermic, control the temperature at 90 ± 5 °C). After the addition is complete, continue the reaction for 2 hours. Cool, filter to remove salts. Remove the solvent by vacuum distillation. Purify the residual liquid by column chromatography (200 - 300 mesh silica gel, elute with dichloromethane / petroleum ether = 1:1) to obtain a light yellow liquid component, 2-butylbenzotriazole (20.6 g, yield 39.2%).

[0122] S2. Disperse 2-butylbenzotriazole (17.5 g, 0.1 mol) in aqueous hydrobromic acid solution (48 wt%, 50 mL), heat to 120 °C until completely dissolved, then cool to room temperature, add bromine (35.2 g, 0.22 mol), and continue heating to 120 °C for reaction for 12 hours. After the reaction is completed, add dichloromethane to extract the product, and wash the organic phase twice with aqueous sodium carbonate solution. Combine the organic phases and evaporate the solvent. Purify the product by column chromatography (200 - 300 mesh silica gel, elute with dichloromethane / petroleum ether = 3:1) to obtain a light yellow solid, M1, 2-n-butyl-4,7-dibromobenzotriazole (23.7 g, yield 71.2%).

[0123] Intermediate M2

[0124]

[0125] The synthesis steps of intermediate M2 are the same as those of M1, except that in step S1, bromobutane is replaced with 1-bromododecane (89.7 g, 0.36 mol) to obtain a light yellow paste solid, 2-n-dodecylbenzotriazole (35.7 g, yield 41.5%); the feeding amount in step S2 is 2-n-dodecylbenzotriazole (28.7 g, 0.1 mol), and the preparation and post-treatment methods are the same, to obtain a light brown solid, M2, 2-n-dodecyl-4,7-dibromobenzotriazole (30.4 g, yield 68.4%).

[0126] Intermediate M3

[0127]

[0128] The synthesis steps of intermediate M3 are the same as those of M1, except that in step S1, bromobutane is replaced with 3-bromopropanol (50.1 g, 0.36 mol) to obtain white solid 2-(3-hydroxypropyl)benzotriazole (20.1 g, yield 37.9%); in step S2, the feed amount is 2-(3-hydroxypropyl)benzotriazole (17.7 g, 0.1 mol), and the preparation and post-treatment methods are the same, obtaining light brown solid M3, 2-(3-hydroxypropyl)-4,7-dibromobenzotriazole (22.1 g, yield 64.2%).

[0129] Intermediate M4

[0130]

[0131] The synthesis steps of intermediate M4 are the same as those of M1, except that in step S1, bromobutane is replaced with 2-phenoxyethyl bromide (72.3 g, 0.36 mol) to obtain light yellow paste solid 2-(phenoxyethyl)benzotriazole (31.1 g, yield 43.4%); in step S2, the feed amount is 2-(phenoxyethyl)benzotriazole (23.9 g, 0.1 mol), and the preparation and post-treatment methods are the same, obtaining light yellow solid M4, 2-(phenoxyethyl)-4,7-dibromobenzotriazole (26.8 g, yield 67.6%).

[0132] Intermediate M5

[0133]

[0134] The synthesis steps of intermediate M5 are the same as those of M1, except that in step S1, the feed amounts are changed to benzotriazole (119.0 g, 1.0 mol), potassium carbonate (414.6 g, 3.0 mol) and N,N-dimethylformamide (DMF, 1000 mL), and bromobutane is replaced with 1-bromo-4-chlorobutane (205.8 g, 1.2 mol) to obtain white solid 2-(4-chlorobutyl)benzotriazole (45.1 g, yield 21.5%); in step S2, the feed amount is 2-(4-chlorobutyl)benzotriazole (21.0 g, 0.1 mol), and the preparation and post-treatment methods are the same, obtaining white solid M5, 2-(4-chlorobutyl)-4,7-dibromobenzotriazole (21.5 g, yield 58.4%).

[0135] Preparation of luminescent material P.

[0136]

[0137] Preparation of the luminescent material P[2-A-yl-4,7-bis(long-chain alkylphenyl)-benzotriazole] is obtained by reacting the intermediate M[2-A-yl-4,7-dibromobenzotriazole] with [long-chain alkylbenzene active substrate] (abbreviated as R-Ph-Z) under catalytic coupling; where R is a C7-C18 straight-chain or branched-chain alkyl group; A is a C1-C18 alkyl group or a derivative of an alkyl group; Z represents an active group that can undergo catalytic coupling reaction, and the active group is selected from boronic acid group, borate group, magnesium bromide Grignard reagent, magnesium chloride Grignard reagent, trifluoromethanesulfonate group.

[0138] Bromoalkylbenzenes and alkylbenzeneboronic acids with various different structures are synthesized according to the methods reported in the literature (J. Am. Chem. Soc. 2023, 145, 4, 2499; Macromolecules 2010, 43, 8063; Angew. Chem. Int. Ed. 2020, 59, 8113), or purchased from suppliers.

[0139] Example 1.

[0140] Liquid luminescent material P1

[0141]

[0142] Note: The % value does not represent the yield, but the proportion of the compound in the total components.

[0143] Dissolve the intermediate M1[2-n-butyl-4,7-dibromobenzotriazole] (6.66 g, 0.02 mol) with n-heptylbenzeneboronic acid (3.87 g, 0.0176 mol, molar proportion 40%), n-decylbenzeneboronic acid (4.03 g, 0.0154 mol, molar proportion 35%), n-dodecylbenzeneboronic acid (3.19 g, 0.011 mol, molar proportion 25%) in toluene (100 mL), add sodium carbonate (4.24 g, 0.04 mol), add 20 mL of water, evacuate and replace with nitrogen three times. Then add the catalyst tetrakis(triphenylphosphine)palladium (2.31 g, 0.002 mol). Under nitrogen protection, heat to 100 °C and react for 12 hours. After the reaction is completed, cool to room temperature, separate and remove the aqueous phase, and evaporate the toluene phase to dryness. Purify by column chromatography (200-300 mesh silica gel), elute with petroleum ether / ethyl acetate to obtain a light yellow oily substance P1 (9.00 g, calculated according to the average molecular weight of 588.3, yield 76.5%).

[0144] 1 HNMR(400M, CDCl 3): δ 7.97 (d, J = 8.0, 4H), 7.60 (s, 2H), 7.32 (d, J = 8.0, 4H), 4.58 (t, J = 7.0, 2H), 2.67 - 2.58 (m, 6H), 1.64 - 0.87 (m, 41H). 1 The HNMR spectrum is as Figure 1 shown below.

[0145] Mass spectrometry (ESI-MS): M / Z = 524.4, 566.4, 593.4, 608.4, 636.5, 664.5, [M + H] + , and according to the peak area integration of the high-resolution mass spectrometry, the proportion of each component can be judged, which is basically consistent with the theoretical proportion. Elemental analysis (%) : C, 82.63 (82.89); H, 10.23 (9.97); N, 7.34 (7.14), and the values in brackets are the theoretical values.

[0146] The oily substance P1 is dissolved in dichloromethane solution (1×10 -5 M), and under the excitation of an ultraviolet lamp, a bright blue light emission can be obtained (λ ex-max = 345 nm, λ em-max = 418 nm).

[0147] Example 2.

[0148] Liquid luminescent material P2

[0149]

[0150] Note: The % value does not represent the yield, but the proportion of the compound in the total components

[0151] The preparation method of the luminescent material P2 is the same as that of Example 1, except that the raw material M1 is replaced with M2 [2-n-dodecyl-4,7-dibromobenzotriazole] (8.90 g, 0.02 mol), and the phenylboronic acid derivative is replaced with 4-n-octylphenylboronic acid (4.12 g, 0.0176 mol, molar proportion 40%), 4-tert-octylphenylboronic acid (3.09 g, 0.0132 mol, molar proportion 30%), 4-tert-butylphenylboronic acid (3.09 g, 0.0132 mol, molar proportion 30%). Purification by column chromatography (200 - 300 mesh silica gel), eluted with petroleum ether / ethyl acetate, to obtain a light yellow liquid P2 (9.71 g, calculated by average molecular weight, yield 73.1%).

[0152] 1 HNMR (400M, CDCl 3):δ 7.98 (d, J = 8.4, 4H), 7.60 (s, 2H), 7.33 (d, J = 8.4, 4H), 4.56 (t, J = 7.1, 2H), 2.65 - 2.57 (m, 4H), 1.66 - 0.89 (m, 53H). Mass spectrometry (ESI-MS): M / Z = 664.5, [M + H] + . Elemental analysis (%) : C, 83.93 (83.20); H, 10.63 (10.47); N, 6.15 (6.33), values in brackets are theoretical values.

[0153] Example 3.

[0154] Liquid luminescent material P3

[0155]

[0156] Note: The % values do not represent the yield, but the proportion of the compound in the total components

[0157] The preparation method of luminescent material P3 is the same as that of Example 1, except that the raw material M1 is replaced with M3 [2-(propan-3-yl)-4,7-dibromobenzotriazole] (8.90 g, 0.02 mol), and the phenylboronic acid derivative is replaced with a mixture of three substrates: 4-(2-ethylhexyl)phenylboronic acid (3.61 g, 0.0154 mol, molar proportion 35%), 3,5-dioctylphenylboronic acid (5.33 g, 0.0154 mol, molar proportion 35%), and 4-decyl-2-methylphenylboronic acid (4.25 g, 0.0132 mol, molar proportion 30%). Purification by column chromatography (200 - 300 mesh silica gel), eluted with petroleum ether / ethyl acetate, to obtain a light yellow liquid mixture P3 (9.36 g, calculated by average molecular weight, yield 71.2%).

[0158] Mass spectrometry (ESI-MS): M / Z = 554.2, 596.4, 638.5, 666.5, 708.6, 778.6, [M + H] + . Elemental analysis (%) : C, 78.68 (78.51); H, 10.04 (10.12); N, 6.23 (6.19), values in brackets are theoretical values (P3 - 1.2H 2 O).

[0159] The liquid mixture P3 is dissolved in dichloromethane solution (1×10 -5 M), and under the excitation of an ultraviolet lamp, a bright blue light emission can be obtained (λ ex-max = 346 nm, λ max = 419 nm).

[0160] Example 4.

[0161] Liquid Luminescent Material P4

[0162]

[0163] Note: The % values do not represent the yield, but the proportion of the compound in the total components. S1: In a 250 mL glass bottle, add 60 mL of ultra-dry diethyl ether and magnesium turnings (1.06 g, 0.044 mol), and dropwise add alkyl bromobenzene (14.12 g, 0.044 mol), where the molar fraction is: decyl bromobenzene 10%, undecyl bromobenzene 30%, dodecyl bromobenzene 40%, tridecyl bromobenzene 20%. Heat to reflux to initiate. After the dropwise addition is complete, continue refluxing for 2 hours, then cool down to complete the preparation of the Grignard reagent.

[0164] S2: Dissolve M4 [2-(phenoxyethyl)-4,7-dibromobenzotriazole] (7.94 g, 0.02 mol) in 20 mL of anhydrous diethyl ether, add the catalyst tetrakis(triphenylphosphine)palladium (1.15 g, 0.001 mol), and then dropwise add the above Grignard reagent into the solution. Heat to reflux for 6 hours. After cooling, distill off the diethyl ether. Purify by column chromatography (200 - 300 mesh silica gel), elute with petroleum ether / ethyl acetate to obtain a slightly yellow oily liquid P4 (11.97 g, calculated by average molecular weight, yield 83.2%).

[0165] Mass spectrometry (ESI-MS): M / Z = 672.5, 686.4, 700.5, 714.5, 728.5, 742.5, 756.6 [M+H] + . Elemental analysis (%): C, 82.77 (82.44); H, 9.28 (9.49); N, 5.76 (5.84), the values in parentheses are the theoretical values.

[0166] The liquid mixture P4 is dissolved in dichloromethane solution (1×10 -5 M), and can obtain bright blue light emission (λ ex-max = 345 nm, λ max = 420 nm) under the excitation of an ultraviolet lamp.

[0167] Example 5.

[0168] Liquid Luminescent Material P5

[0169]

[0170]

[0171] Note: The % values do not represent the yield, but the proportion of the compound in the total components

[0172] S1: In a 250 mL glass reactor, add 60 mL of ultra-dry tetrahydrofuran and magnesium shavings (1.06 g, 0.044 mol). Dropwise add alkyl bromobenzene (14.73 g, 0.044 mol, molar fraction: octyl bromobenzene dodecyl bromobenzene octadecyl bromobenzene ), and heat to reflux to initiate the reaction. After the dropwise addition is complete, continue refluxing for 2 hours, then cool down to complete the preparation of the Grignard reagent.

[0173] S2: Dissolve M5 [2-(4-chlorobutyl)-4,7-dibromobenzotriazole] (7.35 g, 0.02 mol) in 20 mL of anhydrous tetrahydrofuran, add palladium acetate catalyst (0.224 g, 0.001 mol), and then dropwise add the above Grignard reagent. Heat to reflux for 6 hours. After cooling, distill off THF. Purify by column chromatography (200 - 300 mesh silica gel), elute with petroleum ether / ethyl acetate to obtain a slightly yellowish gelatinous mixture O5 (11.72 g, calculated by average molecular weight, yield 81.7%).

[0174] S3: In a 250 mL three-necked flask, add 100 mL of anhydrous tetrahydrofuran, allyl alcohol (1.74 g, 0.03 mol), and sodium hydride (0.72 g, 0.03 mol). Heat to reflux for 2 h to remove the proton of allyl alcohol. Then add intermediate O5 (5.73 g, 0.01 mol) and continue refluxing for 40 hours. Distill off most of the tetrahydrofuran under reduced pressure, then add 100 mL of ethyl acetate to extract the product, wash three times with 100 mL of water, and evaporate the organic phase to dryness. Purify by column chromatography (silica gel adsorption, elute with petroleum ether / ethyl acetate) to obtain allyl ether-substituted benzotriazole luminescent material P5 (5.78 g, calculated by average molecular weight, yield 78.3%, add 0.1% inhibitor BHT to prevent double bond polymerization).

[0175] 1 HNMR (400M, CDCl 3 ): δ 8.05 - 7.98 (m, 4H), 7.59 (s, 2H), 7.40 - 7.34 (m, 4H), 4.95 - 4.87 (m, 5H), 3.89 (s, 2H), 3.51 (t, 2H), 2.57 - 2.40 (m, 8H), 1.83 - 0.86 (m, 50.5H). Mass spectrometry (ESI-MS): M / Z = 608.5, 664.5, 720.5, 748.6, 804.6, 888.6 [M+H] + . Elemental analysis (%): C, 81.93 (81.82); H, 10.54 (10.32); N, 5.76 (5.69), the values in parentheses are theoretical values (P5 - 5%wt petroleum ether, avoid high-temperature drying to prevent polymerization).

[0176] The liquid mixture P5 is dissolved in dichloromethane solution (1×10 -5 M), and bright blue light emission can be obtained under ultraviolet light excitation (λ ex-max = 344 nm, λ max = 418 nm).

[0177] Comparative Example 1

[0178] Solid-state luminescent materials R1-1 to R1-6

[0179]

[0180]

[0181] The preparation methods of the comparative example luminescent materials R1-1 to R1-6 are the same as those of Example 1, except that the raw material phenylboronic acid derivative is replaced with a single type of alkylphenylboronic acid. After purification by column chromatography, white to slightly yellow powdery solids R1-1 to R1-6 are obtained (yield 75 - 85%). Mass spectrometry (ESI-MS): M / Z = 524.4 (R1-1), M / Z = 636.5 (R1-2), M / Z = 552.4 (R1-3), M / Z = 552.4 (R1-4), M / Z = 776.7 (R1-5), M / Z = 636.5 (R1-6), [M+H] + .

[0182] Comparative Example 2

[0183] Solid-state luminescent material R2

[0184]

[0185] Note: The % value does not represent the yield, but the proportion of the compound in the total components

[0186] The preparation method of the comparative example luminescent material R2 is the same as that of Example 1, except that the raw material M1 is replaced with M2 [2-n-dodecyl-4,7-dibromobenzotriazole] (8.90 g, 0.02 mol), and the phenylboronic acid derivative is replaced with 4-octylphenylboronic acid (5.15 g, 0.022 mol), 4-dodecylphenylboronic acid (6.16 g, 0.022 mol). After purification by column chromatography, a light yellow solid R2 (10.24 g, yield 71.1%) is obtained. Mass spectrometry (ESI-MS): M / Z = 664.5, 720.5, 776.6, [M+H] + .

[0187] Comparative Example 3

[0188] Solid-state luminescent material R3

[0189]

[0190] The preparation method of the short-chain alkyl-substituted solid-state luminescent material R3 is the same as that of Comparative Example 1, except that the raw material M1 is replaced with M3 [2-(propan-3-yl)-4,7-dibromobenzotriazole] (8.90 g, 0.02 mol), and the phenylboronic acid derivative is replaced with 4-tert-butylphenylboronic acid (7.83 g, 0.044 mol). Purification by column chromatography gave a white powdery solid R3 (6.99 g, yield 79.2%). Mass spectrometry (ESI-MS): M / Z = 442.3, [M+H] + 。

[0191] Comparative Example 4

[0192] Solid-state luminescent material R4

[0193]

[0194] The preparation method of the short-chain alkyl-substituted solid-state luminescent material R4 is the same as that of Comparative Example 1, except that the raw material M1 is replaced with M4 [2-(phenoxyethyl)-4,7-dibromobenzotriazole] (7.94 g, 0.02 mol), and the phenylboronic acid derivative is replaced with a single type of 4-ethylphenylboronic acid (6.60 g, 0.044 mol). Purification by column chromatography gave a slightly yellow powdery solid R4 (6.07 g, yield 67.8%). Mass spectrometry (ESI-MS): M / Z = 448.3, [M+H] + 。

[0195] Constructing a mixture luminescent material by physical mixing method.

[0196] Examples 6 to 10, Comparative Examples 5 to 8

[0197] Mix the luminescent materials of Comparative Example 1 and Comparative Example 2 according to the designed ratio (molar ratio), add dichloromethane as a solvent to assist dissolution. After complete dissolution, the solvent was removed by rotary evaporation and dried under vacuum to obtain the mixture luminescent material. According to different formulations, some materials are in a liquid state, some are in a colloidal state, and some partially precipitate solids, as shown in the following table.

[0198] Table 1 States of mixtures of materials with different formulations

[0199]

[0200]

[0201] As can be seen from the table, 4,7-diphenylbenzotriazole-based mixture luminescent materials can also be obtained by mixing compounds with different structures in a certain proportion. When the mixture contains six components, and the molar ratio of a single component does not exceed 30%, the sum of the first three components does not exceed 80%, the sum of the first four components does not exceed 85%, and the sum of the first five components does not exceed 95%, several examples (P6 - P10) can obtain liquid 4,7-diphenylbenzotriazole-based luminescent materials.

[0202] In contrast, when the proportion of a single structure in the mixture exceeds 40 - 50% (R5, R7, R8), the material presents a colloidal state, and even local solid precipitation occurs. When the mixture contains only 4 components (R6), the mixture presents a colloidal state. In Comparative Example 2, a mixture of 3 components (R2) was prepared by the "one-pot method", and the material presented a solid state.

[0203] Material with a composite formulation of a liquid luminescent material and a small amount of a short-chain alkyl-substituted structure

[0204] Example 11

[0205] Composite formulation material P11

[0206] To 9.0 g of the long-chain alkyl-substituted liquid benzotriazole-based luminescent material P1 obtained in Example 1, 1.0 g of the tert-butyl-substituted solid benzotriazole-based luminescent material R3 of Comparative Example 3 was added. The mixture was heated to 120 °C and continuously stirred until the solid material R3 was completely dissolved. Then it was cooled to room temperature to obtain the composite formulation material P11 (a light yellow viscous transparent liquid, without solid precipitation). In this formulation, the proportion of the short-chain solid luminescent material is 10 w / w%.

[0207] Example 12

[0208] Composite formulation material P12

[0209] To 9.0 g of the long-chain alkyl-substituted liquid benzotriazole-based luminescent material P3 obtained in Example 3, 1.0 g of the ethyl-substituted solid benzotriazole-based luminescent material R4 of Comparative Example 4 was added. The mixture was heated to 120 °C and continuously stirred until the solid material R4 was completely dissolved. Then it was cooled to room temperature to obtain the composite formulation material P12 (a light yellow viscous transparent liquid, without solid precipitation). In this formulation, the total proportion of the short-chain solid luminescent material is 10 w / w%.

[0210] Comparative Example 9

[0211] Composite formulation material R9

[0212] In the long-chain alkyl-substituted liquid benzotriazole-based luminescent material P1 (8.0 g) obtained in Example 1, add the tert-butyl-substituted solid benzotriazole-based luminescent material R3 (1.0 g) of Comparative Example 3 and the ethyl-substituted solid benzotriazole-based luminescent material R4 (1.0 g) of Comparative Example 4. Heat to 120 °C and continuously stir until the solid materials R3 and R4 are completely dissolved. Cool to room temperature to obtain the material R9 with a composite formulation (a viscous transparent jelly, and solids gradually precipitate out after standing overnight). In this formulation, the proportion of the short-chain solid luminescent material is 20 w / w%.

[0213] Material with a composite formulation of a liquid luminescent material, a liquid auxiliary agent, and a readily soluble solid auxiliary agent

[0214] Example 13

[0215] Material P13 with a composite formulation

[0216] In the long-chain alkyl-substituted liquid benzotriazole-based luminescent material P1 (5.0 g) obtained in Example 1, add the crosslinking aid trimethylolpropane triacrylate (liquid, 2.0 g), γ-glycidoxypropyltrimethoxysilane (liquid, 2.0 g), and the light stabilizer Chiguard 353 (liquid, 1.0 g). Heat to 80 °C and continuously stir until the materials are completely and uniformly dispersed. Cool to room temperature to obtain the material P13 with a composite formulation (a light yellow viscous transparent liquid). In this formulation, the proportion of the liquid benzotriazole-based luminescent material is 50 w / w%, and the proportion of the liquid auxiliary agent is 50%.

[0217] Example 14

[0218] Material P14 with a composite formulation

[0219] In the long-chain alkyl-substituted liquid benzotriazole-based luminescent material P4 (4.0 g) obtained in Example 4, add the crosslinking aid trimethylolpropane triacrylate (liquid, 2.0 g), γ-glycidoxypropyltrimethoxysilane (liquid, 2.0 g), and the light stabilizer HS-944 (solid, 2.0 g). Heat to 80 °C and continuously stir until the materials are completely and uniformly dispersed. Cool to room temperature to obtain the material P14 with a composite formulation (a light yellow viscous transparent liquid, and no solids precipitate). In this formulation, the proportion of the liquid benzotriazole-based luminescent material is 40 w / w%, the proportion of the liquid auxiliary agent is 40%, and the proportion of the readily soluble solid auxiliary agent is 20%.

[0220] Preparation and characterization of the light conversion film

[0221] Example 15

[0222] In this embodiment, the auxiliaries used include crosslinking agents, co-crosslinking agents, light stabilizers, etc., all of which are commonly used liquid auxiliaries. The amounts of the auxiliaries are as follows: the crosslinking agent tert-butyl peroxy-3,5,5-trimethylhexanoate (0.5 wt%), the co-crosslinking agents trimethylolpropane triacrylate (0.3 wt%) and γ-glycidoxypropyltrimethoxysilane (0.3 wt%), and the light stabilizer bis(1,2,2,6,6-pentamethylpiperidinol) sebacate (0.4 wt%); the amount of the light conversion agent is 0.2 wt%; all the percentages are calculated based on the total mass of the EVA or POE resin in the film being 100 wt%.

[0223] (1) Dispersion of the light conversion agent. Dispersion method 1: Disperse it in the liquid auxiliary. Weigh 0.2 wt% of the luminescent materials in Examples (1-6, 9, 11) and Comparative Examples (1-3) respectively, directly mix them with the liquid auxiliary, and heat to 80 °C for mixing (the peroxide crosslinking agent is not added first, and is added last after mixing and cooling). Dispersion method 2: Prepare the light conversion masterbatch. Mix the light conversion agent with 20 times its mass of EVA or POE resin in a high-speed mixer, and then granulate it by means of a screw extruder to obtain a high-concentration light conversion masterbatch; the light conversion masterbatch is dried in a dryer for standby.

[0224] (2) Preparation of the film. Mix the light conversion agent (or high-concentration light conversion masterbatch) dispersed in the liquid auxiliary with blank EVA or POE resin particles according to the ratio, and further cast it by a casting machine to obtain the light conversion film (thickness 450 μm).

[0225] (3) Lamination of the film. Cut the above film into a size of 60*80 mm, place it between two pieces of ultra-clear tempered glass of the same size, put it into a laminator, the lamination temperature is 145 °C, the vacuum is -90 kPa, and the lamination time is 20 minutes to prepare the laminated film sample.

[0226] Example 16

[0227] Use a PerkinElmer Lambda750 ultraviolet-visible spectrophotometer with an integrating sphere to measure the visible light transmittance (T, 400 - 700 nm, calculate the average value) of the film; use a Tianmei FLS 1000 fluorescence spectrometer to measure the excitation and emission spectra (Ex, Em) and the photoluminescence quantum yield (PLQY); use a Diffusion EEL 57D haze meter to measure the haze value.

[0228] By measuring the transmittance and haze value of the film after being placed for two months, it is used to characterize whether the luminescent material aggregates and precipitates in the film. The test results are shown in Table 2.

[0229] Table 2 Performance test of the light conversion film

[0230]

[0231]

[0232] The fluorescence excitation and emission spectra of the test film were measured. For the luminescent materials in Examples (1 - 6, 9, 11) and Comparative Examples (1 - 3), they are all 2,6 - diphenyl - 4,7 - diphenylbenzotriazole - type compounds with similar main structures. Therefore, their excitation and emission spectra have little difference. The excitation spectrum ranges from 300 - 400 nm (excitation peak at 340 - 350 nm), the emission spectrum ranges from 380 - 490 nm (emission peak at 415 - 420 nm), and the full width at half maximum is about 55 nm (the excitation and emission spectra of Film 1# are as shown in Figure 2 ). The photoluminescence quantum yield (PLQY) of the light - converting film in the test example was measured and can reach over 90%, that is, more than 90% of the absorbed ultraviolet light can be converted into blue light (the test results of the luminescence quantum efficiency of Film 1# are as shown in Figure 3 ), and the PLQY value is 93.6%). The test results show that the prepared light - converting film has a spectral conversion function and can efficiently convert ultraviolet light in sunlight into blue light. The light - converting film can be applied to HJT heterojunction photovoltaic modules, perovskite photovoltaic modules, and TOPcon photovoltaic modules, playing a role in protecting the functional layer from ultraviolet damage and improving the power generation efficiency.

[0233] During the preparation process of the light - converting film (in Example 15), there are two ways to add the light - converting agent, namely (1) dispersing it in a liquid additive or (2) preparing a light - converting masterbatch. As can be seen from Table 2, for the 1 - 17# light - converting films (adding the luminescent materials of Examples 1 - 6, 9, 11 of the present invention), they can all be added by mixing with a liquid additive. The visible - light transmittance of the prepared films is greater than 92%, and the haze is less than 0.9%, which proves that the liquid benzotriazole - type luminescent materials of Examples (1 - 6, 9, 11) of the present invention have good dispersibility. Due to the substitution with long - chain alkyl groups and the strategy of mixing alkyl chains with different structures, the material does not have crystallinity, so it can be easily dispersed in various liquid additives to achieve single - molecule - level dispersion.

[0234] However, the crystalline benzotriazole - type luminescent materials (R1 - R3) in Comparative Examples 1 - 3 are not suitable for this simple way of mixing and adding with liquid additives. For example, the visible - light transmittance of the prepared 9 - 11# films is less than 90%, the haze is greater than 3%, and the luminescence efficiency is lower than 89%, indicating poor dispersibility of the light - converting agent. Moreover, it can be seen with the naked eye that there are crystal points in the film. These phenomena show that the material cannot be well - dispersed in the liquid additive, and this simple processing method cannot meet the commercial requirements.

[0235] To achieve sufficient dispersion, the crystalline benzotriazole-based luminescent materials of Comparative Examples 1 to 3 need to be used to prepare high-concentration light conversion masterbatches by means of screw extrusion, and further prepare light conversion films. As shown in the 15th to 17th # films in Table 2, by preparing the light conversion masterbatch, the light transmittance of the obtained film can reach more than 92%, and the haze is less than 0.8%. However, this processing method is more troublesome, and the masterbatch needs to be fully dried after granulation, otherwise bubbles will be generated and affect the film quality.

[0236] It should be particularly noted that although the films (15th to 17th # films) prepared from the crystalline benzotriazole-based luminescent materials of Comparative Examples 1 to 3 have good initial dispersibility, after being stored for 2 months, the visible light transmittance decreases significantly (below 91%), and the haze increases (above 2%). This indicates that aggregation and precipitation occur during the storage of the film.

[0237] For the films (1st to 8th # films, 12th to 14th # films) prepared from the liquid luminescent materials of the examples of the present invention (1 to 6, 9, 11), whether added in the form of being dissolved in a liquid auxiliary agent or prepared into a light conversion masterbatch, after being stored for 2 months, there will be no significant decrease in light transmittance or increase in haze. This proves that this type of material has better stability during long-term use, can effectively avoid the aggregation and precipitation of the material, and also indicates that the films prepared from the inventive products have a longer effective service life.

[0238] Example 17

[0239] Preparation of films of other materials

[0240] 18# film: silicone gel film. Select the liquid luminescent material P1 of Example 1, and incorporate it into the silicone sol-gel at a ratio of 0.2 wt%, heat to 100 °C, dissolve, disperse and stir evenly to obtain a light conversion silicone gel containing a light conversion agent. The visible light transmittance of the light conversion gel is tested to be greater than 93%; under ultraviolet light excitation, bright blue light emission can be obtained.

[0241] 19# film: PMMA (polymethyl methacrylate) film. Select the liquid luminescent material P3 of Example 3, and incorporate it into the toluene solution of PMMA (polymethyl methacrylate) at a ratio of 0.2 wt% (the ratio to the dry PMMA resin) (10% PMMA @ toluene), and after scraping coating and the volatilization of toluene, a PMMA light conversion film with a thickness of 100 microns is obtained. The visible light transmittance of the light conversion film is tested to be greater than 91%; under ultraviolet light excitation, bright blue light emission can be obtained.

[0242] 20# Film: PET (polyethylene terephthalate) film. Select the liquid light-emitting material P4 of Example 4, mix it with PET resin at 2 wt% (proportion by dry weight of PET resin), and perform twin-screw extrusion at 210 °C to obtain a high-concentration light conversion masterbatch. Mix the light conversion masterbatch with pure PET particles at a mass ratio of 1:9, and perform melt extrusion and biaxial stretching to obtain a PET light conversion film with a thickness of 200 microns (the final incorporation ratio of the light conversion agent is 0.2 wt%). Test that the visible light transmittance of the light conversion film is greater than 91%; under ultraviolet light excitation, bright blue light emission can be obtained.

[0243] Example 18

[0244] Improvement of the efficiency of HJT heterojunction components by the light conversion adhesive film

[0245] Select the light conversion adhesive films (1#, 2#, 7#) prepared in Example 16 to perform lamination and encapsulation on HJT heterojunction solar cells. The encapsulation structure from bottom to top is as follows: ultra-white tempered glass, light conversion adhesive film, heterojunction cell matrix connected in series and parallel, light conversion adhesive film, ultra-white tempered glass. The lamination process is the same as the adhesive film lamination process in Example 15. Perform power generation power test on the laminated components, and compare the gain effects of the light conversion adhesive film and the ultraviolet cut-off adhesive film (containing 0.1 wt% ultraviolet absorber UV531) (EVA adhesive film and POE adhesive film are compared respectively).

[0246] Table 3 Power test of HJT heterojunction components using the light conversion adhesive film

[0247]

[0248] Through Example 18, it can be seen that the light conversion adhesive film prepared by the present invention can be applied to the field of heterojunction photovoltaic components, can effectively absorb ultraviolet light and convert it into visible light (blue-violet light), and while protecting the photovoltaic components, effectively improve the power generation efficiency of solar cells.

[0249] In perovskite photovoltaic components and TOPCon crystalline silicon components (it is reported in the literature that ultraviolet light will also damage the components), the light conversion adhesive film prepared by the present invention also has application prospects.

[0250] The above-described embodiments are only some preferred solutions of the present invention, but they are not intended to limit the present invention. Those of ordinary skill in the relevant technical field can still make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all technical solutions obtained by adopting equivalent substitution or equivalent transformation fall within the protection scope of the present invention.

Claims

1. A benzotriazole photoluminescent material, characterized in that: The photoluminescent material is a mixture of 4,7-diphenylbenzotriazole compounds substituted with long-chain alkyl groups of different structures, wherein the long-chain alkyl group refers to a C7-C18 straight-chain or branched alkyl group, and the structure of the 4,7-diphenylbenzotriazole compound substituted with long-chain alkyl group is shown in Formula I: In Formula I, R a ~R e , R h ~R l are each independently a hydrogen atom or a C1-C18 alkyl group, and R a ~R e At least one of the groups is a C7-C18 straight chain or branched chain alkyl group, R h ~R l At least one of the groups is a C7-C18 straight-chain or branched alkyl group; A is a C1-C18 alkyl group or a derivative of a C1-C18 alkyl group, wherein the derivative of a C1-C18 alkyl group refers to an alkyl derivative with a functional group molecular weight of less than 400 formed by substitution of a C1-C18 alkyl group with an ether group, an ester group, a hydroxyl group, a thiol group, a carboxyl group, a halogen group, a cyano group, an amino group, an amide group, a C1-C6 alkenyl group, a C1-C6 alkynyl group, a C1-C6 alkyl group, a halogenated C1-C6 alkyl group, a C1-C6 alkoxy group, an aryl group, a heteroaryl group, and a combination thereof; The mixture contains six or more long-chain alkyl substituted components with different structures, the molar fraction of any one long-chain alkyl substituted component does not exceed 30%, the sum of the molar fractions of the top three long-chain alkyl substituted components does not exceed 70%, the sum of the molar fractions of the top four long-chain alkyl substituted components does not exceed 85%, and the sum of the molar fractions of the top five long-chain alkyl substituted components does not exceed 95%; The mixture is highly disordered and behaves as a liquid at room temperature.

2. The liquid benzotriazole photoluminescent material according to claim 1, characterized in that: The liquid benzotriazole photoluminescent material is prepared by catalytic coupling reaction of one or more [2-amino-4,7-dibromobenzotriazole] represented by formula M and three or more [long-chain alkyl-substituted phenyl derivative active substrate] represented by formula N with different structures, and the reaction equation is shown in formula a: In formula a, ... represents a phenyl derivative represented by formula b with different structures; in formula b, R a ~R e Each is independently a hydrogen atom or a C1-C18 alkyl group, and at least one is a C7-C18 straight-chain or branched-chain alkyl group; The range of the substituent A is as described in claim 1; Z represents an active group that can catalyze the coupling reaction, and the active group is selected from a boric acid group, a boric ester group, a magnesium bromide Grignard reagent, a magnesium chloride Grignard reagent, a magnesium iodide Grignard reagent, and a triflate; In the preparation, among three or more [long-chain alkyl substituted phenyl derivative active substrates] represented by formula N with different structures, the molar fraction of the first [long-chain alkyl substituted phenyl derivative active substrate] does not exceed 40%, the molar fraction of the second [long-chain alkyl substituted phenyl derivative active substrate] does not exceed 35%, and the molar fraction of the third [long-chain alkyl substituted phenyl derivative active substrate] does not exceed 34%.

3. The liquid benzotriazole photoluminescent material according to claim 1, characterized in that: The structure of the long-chain alkyl-substituted 4,7-diphenylbenzotriazole compound is shown in Formula II: In formula II, It means that there is an R1 or R2 substituent at any position on the benzene ring; R1 and R2 are each independently a C7-C18 straight chain or branched alkyl group; the range of the A substituent is as described in claim 1; The mixture contains six or more long-chain alkyl substituted components with different structures, the molar fraction of any one long-chain alkyl substituted component does not exceed 30%, the sum of the molar fractions of the top three long-chain alkyl substituted components does not exceed 70%, the sum of the molar fractions of the top four long-chain alkyl substituted components does not exceed 85%, and the sum of the molar fractions of the top five long-chain alkyl substituted components does not exceed 95%; The mixture is highly disordered and behaves as a liquid at room temperature.

4. The liquid benzotriazole photoluminescent material according to claim 3, characterized in that: The liquid benzotriazole photoluminescent material is prepared by catalytic coupling reaction of one or more [2-amino-4,7-dibromobenzotriazole] represented by formula M and three or more [long-chain alkyl-substituted phenyl derivative active substrate] represented by formula N with different structures, and the reaction equation is shown in formula a: In formula a, ... represents a phenyl derivative of formula b with different structures, wherein R1 represents an R1 substituent at any position on the benzene ring, and R1 is a C7-C18 straight chain or branched alkyl group; The range of the A substituent is as described in claim 1; the range of the Z group is as described in claim 2; In the preparation, among three or more [long-chain alkyl substituted phenyl derivative active substrates] represented by formula N with different structures, the molar fraction of the first [long-chain alkyl substituted phenyl derivative active substrate] does not exceed 40%, the molar fraction of the second [long-chain alkyl substituted phenyl derivative active substrate] does not exceed 35%, and the molar fraction of the third [long-chain alkyl substituted phenyl derivative active substrate] does not exceed 34%.

5. The liquid benzotriazole photoluminescent material according to claim 3, characterized in that: In the 4,7-diphenylbenzotriazole compounds, the substituent A is a C1~C18 alkyl group or a derivative of a C1~C18 alkyl group, and the derivative of the C1~C18 alkyl group refers to an alkyl derivative with a functional group molecular weight of less than 400 formed by replacing the C1~C18 alkyl group with an ether group, an ester group, a hydroxyl group, a carboxyl group, an amide group, a C1-C6 alkyl group, a C1-C6 alkenyl group, a C1-C6 alkoxy group, a phenyl group and a combination thereof.

6. The liquid benzotriazole photoluminescent material according to claim 3, characterized in that: The 4,7-diphenylbenzotriazole compound is selected from the structures shown in formula III-a to III-1, IV-a to IV-f, and formula Va to Vf: In formulae III-a to III-l, IV-a to IV-f, and Va to Vf, R1 and R2 are each independently a C7-C18 straight chain or branched chain alkyl group; in formulae Va to Vf, X is a straight chain or branched chain C1 to C18 alkylene group.

7. A method for preparing a liquid benzotriazole photoluminescent material, characterized in that: The preparation method is shown in reaction formula a, wherein one or more [2-amino-4,7-dibromobenzotriazole] of formula M and three or more [long-chain alkyl-substituted phenyl derivative active substrate] of formula N with different structures are added with solvent and catalyst, and then subjected to catalytic coupling reaction to directly obtain a mixture of [4,7-diphenylbenzotriazole] with different structures in a one-pot process: In formula a, ... represents phenyl derivatives of formula b with different structures, wherein R a ~R e Each is independently a hydrogen atom or a C1-C18 alkyl group, and at least one is a C7-C18 straight-chain or branched-chain alkyl group; In the preparation method, among three or more [long-chain alkyl substituted phenyl derivative active substrates] represented by formula N with different structures, the molar fraction of the first [long-chain alkyl substituted phenyl derivative active substrate] does not exceed 40%, the molar fraction of the second [long-chain alkyl substituted phenyl derivative active substrate] does not exceed 35%, and the molar fraction of the third [long-chain alkyl substituted phenyl derivative active substrate] does not exceed 34%; The range of the substituent A is as described in claim 1; Z represents an active group that can undergo a catalytic coupling reaction, and the active group is selected from a boric acid group, a boric ester group, a magnesium bromide Grignard reagent, a magnesium chloride Grignard reagent, a magnesium iodide Grignard reagent, and a trifluoromethanesulfonate.

8. The method for preparing a liquid benzotriazole photoluminescent material according to claim 7, characterized in that: The solvent of the reaction is selected from a mixture of one or more of diethyl ether, tetrahydrofuran, dioxane and toluene; the catalyst of the reaction is selected from a nickel catalyst and a palladium catalyst; and the reaction temperature is room temperature to reflux temperature.

9. A composite material consisting of a long-chain alkyl-substituted liquid benzotriazole photoluminescent material and a non-long-chain alkyl-substituted solid benzotriazole luminescent compound, characterized in that: The composite material comprises a long-chain alkyl-substituted liquid benzotriazole-based photoluminescent material as described in any one of claims 1 to 6 and one or more non-long-chain alkyl-substituted 4,7-diphenylbenzotriazole-based luminescent compounds with a molar fraction not exceeding 10%; the structure of the non-long-chain alkyl-substituted 4,7-diphenylbenzotriazole-based luminescent compound is shown in Formula I: Among them, R a ~R e , R h ~R l Each is independently selected from a hydrogen atom, a C1-C6 alkyl group; the range of the substituent A is as described in claim 1; The appearance of the composite material is liquid.

10. A composite material of a liquid benzotriazole photoluminescent material, a liquid auxiliary agent, and a readily soluble solid auxiliary agent, characterized in that: The composite material comprises a liquid benzotriazole-based photoluminescent material as described in any one of claims 1 to 6 and 9, a liquid auxiliary agent, and a readily soluble solid auxiliary agent, and the liquid auxiliary agent and the readily soluble solid auxiliary agent are selected from peroxide crosslinking agents, silane coupling agents, crosslinking auxiliary agents, light stabilizers, antioxidants, ultraviolet absorbers, and other inert auxiliary agents that do not affect the film-forming formulation; The mass fraction of the liquid benzotriazole-based photoluminescent material is x, the mass fraction of the liquid auxiliary agent is y, and the mass fraction of the readily soluble solid auxiliary agent is z, where 20 w / w% ≤ x < 100 w / w%, 0 w / w% < y ≤ 80 w / w%, 0 w / w% ≤ z ≤ 20 w / w%, and x + y + z = 100 w / w%.

11. The composite material according to claim 10, characterized in that The proportion of the readily soluble solid auxiliary agent is 0 w / w%.

12. A polymer complex having light conversion function, characterized in that: The polymer composite comprises an optically transparent polymer matrix and a liquid benzotriazole-based photoluminescent material as described in any one of claims 1 to 6 and 9 to 11.

13. The polymer composite with a light conversion function as claimed in claim 12, wherein the liquid or colloidal benzotriazole-based photoluminescent material is present in the polymer matrix in an amount of 0.01 to 5 wt%.

14. The polymer composite with a light conversion function as claimed in claim 13, wherein the polymer matrix is selected from polyethylene terephthalate, polyacrylate, polymethyl methacrylate, polyvinyl butyral, ethylene-vinyl acetate copolymer (EVA), polyolefin elastomer (POE), ethylene-tetrafluoroethylene copolymer, polyimide, amorphous polycarbonate, polystyrene, silicone sol-gel, polyurethane, and combinations thereof.

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