A m-nitroacetylene-based luminescent modified material and its preparation method

Abstract

This invention discloses a m-nitroacetylene-based luminescent modified material and its preparation method. The luminescent modified material is a dispersion formed from a m-nitroacetylene-based luminescent intermediate, a film-forming regulator, and a film-forming solvent. The m-nitroacetylene-based luminescent intermediate is prepared by a palladium-catalyzed coupling reaction of nano-silica-m-nitroacetylene triphenylamine composite monomer, 3,6-dibromo-9-octylcarbazole, and 1,4-diethynylbenzene, followed by precipitation purification and drying. Through nano-silica surface activation, m-nitroacetylene triphenylamine structural composite, carbazole-acetylene aromatic structure coupling, precipitation purification, and film-forming regulation, a luminescent modified material with high fluorescence quantum yield, good dispersion stability, film uniformity, and thermal stability under the conditions described in the examples is obtained, suitable for the fields of organic electroluminescent materials and optoelectronic functional thin films.

Description

Technical Field

[0001] This invention relates to the field of organic electroluminescent materials technology, specifically to a m-nitroacetylene-based luminescent modified material and its preparation method. Background Technology

[0002] Organic electroluminescent materials are widely used in displays, lighting, optoelectronic functional thin films, and luminescent modification materials due to their high luminous efficiency, strong structural designability, and good processing adaptability. As optoelectronic devices develop towards higher brightness, higher stability, thinner films, and greater flexibility, higher requirements are placed on the fluorescence emission performance, dispersion stability, film uniformity, and thermal stability of luminescent modification materials.

[0003] In existing technologies, to improve the overall performance of organic light-emitting materials, conjugated units such as triphenylamine, carbazole, and acetylene aromatic structures are typically introduced to enhance the material's charge carrier transport capacity and luminescence performance. Among these, the triphenylamine structure exhibits good electron-donating ability, the carbazole structure possesses high rigidity and thermal stability, and the acetylene group structure can extend the molecular conjugation length, which is beneficial for constructing a stable luminescent conjugated system. However, in the actual preparation and film formation process, conventional organic light-emitting modified materials are still prone to problems such as insufficient dispersion stability, poor film continuity, local agglomeration, or numerous pinholes, which in turn affect the uniformity and stability of the luminescent modified film.

[0004] In existing technologies, there are also methods to improve the thermal stability and film support performance of materials by introducing inorganic nano-components such as nano-silica. However, ordinary nano-silica has a strong surface polarity and limited interfacial compatibility with organic conjugated luminescent structures. If it is introduced by simply using physical mixing, it is easy to cause uneven dispersion of nanoparticles, insufficient interfacial bonding, and insufficient synergistic effect between organic and inorganic phases, making it difficult to simultaneously achieve fluorescence emission performance, dispersion stability, film uniformity, and thermal stability.

[0005] Therefore, developing a m-nitroacetylene-based luminescent modified material with a m-nitroacetylene triphenylamine structure as the luminescent functional unit, combined with nano-silica surface activation modification, carbazole copolymerization, and film-forming regulation system, so that it can maintain fluorescence emission performance while having good dispersion stability, low film roughness, fewer pinholes, and high thermal stability, has become a direction that needs further improvement in this field. Summary of the Invention

[0006] The purpose of this invention is to address the technical problems of existing organic luminescent modified materials, such as insufficient interfacial compatibility between inorganic nanocomponents and organic conjugated structures, easy aggregation of nanoparticles, poor dispersion stability, insufficient film continuity during film formation, high surface roughness, numerous pinholes, and the need to improve thermal stability. This invention provides a m-nitroacetylene-based luminescent modified material and its preparation method. The aim is to improve the interfacial bonding and dispersion uniformity between organic and inorganic components by surface activation modification of nano-silica and its composite with a m-nitroacetylene triphenylamine structure, combined with a carbazole structure, an acetylene aromatic structure, and a film-forming regulation system. This enhances the material's fluorescence emission performance, dispersion stability, film uniformity, and thermal stability.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A m-nitroacetylene-based luminescent modification material, by weight, is prepared from the following raw materials in parts by weight: 12-30 parts of nano-silica-m-nitroacetylene triphenylamine composite monomer, 8-22 parts of 3,6-dibromo-9-octylcarbazole, 6-18 parts of 1,4-diacetylenolbenzene, 0.3-2.5 parts of blocking agent, 0.05-0.60 parts of palladium catalytic system, 0.03-0.35 parts of cuprous iodide, 20-70 parts of organic base, 160-320 parts of anhydrous organic solvent, 2-12 parts of film-forming regulator, and 120-450 parts of purification solvent.

[0008] Furthermore, the nano-silica-m-nitroacetylene triphenylamine composite monomer is composed of the following raw material components: 15-35 parts of 4,4'-dibromotriphenylamine, 5-16 parts of 3-nitrophenylacetylene, 3-10 parts of nano-silica, and 1-5 parts of 3-aminopropyltriethoxysilane.

[0009] Furthermore, the preparation method of the nano-silica-m-nitroacetylene triphenylamine composite monomer includes the following steps: A1. Add the nano-silica to a mixture of anhydrous ethanol and deionized water, controlling the solid-liquid ratio at 1g:15-30mL, and disperse for 20-50min at 25-35℃ and 500-900r / min; add the 3-aminopropyltriethoxysilane, and adjust the pH to 4.5-5.8 with glacial acetic acid, react at 35-55℃ for 2-5h, centrifuge, and wash until the pH of the washing solution is 6.5-7.2 to obtain wet nano-silica.

[0010] A2. Add 80-220 parts of anhydrous tetrahydrofuran and 40-120 parts of anhydrous toluene to a reaction vessel, purge with nitrogen for 30-60 min, add the 4,4'-dibromotriphenylamine and 3-nitrobenzyl acetylene, stir for 15-40 min, then add 0.05-0.40 parts of bis(triphenylphosphine)palladium dichloride, 0.03-0.25 parts of cuprous iodide and 25-90 parts of triethylamine, and react at 55-75℃ and 400-700 r / min for 8-18 h to obtain reaction solution A.

[0011] A3. Add the wet nano-silica material to the reaction solution A; based on the dry weight of the wet nano-silica material, control the solid-liquid ratio of it to the reaction solution A to be 1g:25-60mL, and perform a composite reaction at 60-80℃ and 500-800r / min for 4-10h to obtain reaction solution B.

[0012] A4. Cool the reaction solution B to 20-30℃, filter to remove insoluble matter, and collect the solid by centrifugation at 6000-9000 r / min for 5-12 min. Wash the obtained solid sequentially with organic detergent and deionized water until the pH of the washing solution is 6.5-7.2 when washing with deionized water for the last time. Then, vacuum dry at 45-65℃ for 8-16 h, grind for 20-50 min and pass through a 200-400 mesh sieve to obtain nano-silica-m-nitroacetylene triphenylamine composite monomer.

[0013] In step A4, the organic detergent is one or more of methanol, ethanol, ethyl acetate, acetone, and n-hexane.

[0014] Furthermore, the sealing agent is selected from one or more of phenylacetylene, 4-tert-butylphenylacetylene, and trimethylsilylacetylene.

[0015] Furthermore, the palladium catalytic system is a catalytic system composed of palladium acetate and triphenylphosphine, wherein the mass ratio of palladium acetate to triphenylphosphine is 1:2.5-1:9.5.

[0016] Furthermore, the organic base is one or more of triethylamine, diisopropylamine, diethylamine, piperidine, and N,N-diisopropylethylamine.

[0017] Furthermore, the anhydrous organic solvent is one or more of anhydrous tetrahydrofuran, anhydrous toluene, anhydrous N,N-dimethylformamide, and anhydrous 1,4-dioxane.

[0018] Furthermore, the film-forming regulator is one or more of polyvinylcarbazole, polymethyl methacrylate, and polystyrene.

[0019] Furthermore, the purification solvent is one or more of methanol, ethanol, n-hexane, petroleum ether, and ethyl acetate.

[0020] This invention also provides a method for preparing a m-nitroacetylene-based luminescent modified material, comprising the following steps: S1. Weigh the nano-silica-m-nitroacetylenetriphenylamine composite monomer, 3,6-dibromo-9-octylcarbazole, 1,4-diacetylbenzene, palladium catalytic system, cuprous iodide, organic base and anhydrous organic solvent, add the above raw materials to the reaction vessel, purge with nitrogen for 30-60 min, and stir for 20-40 min at 20-30℃ and 400-700 r / min to obtain a deoxygenated dispersion.

[0021] S2. The deoxygenated dispersion is heated to 60-85℃ and reacted for 8-20 hours under nitrogen protection and stirring at 400-700 r / min. Then, a blocking agent is added at a rate of 0.03-0.15 parts / min, and the reaction continues for 2-6 hours to obtain a reaction solution of m-nitroacetylene-based luminescent modified material.

[0022] S3. Cool the reaction solution of the m-nitroacetylene-based luminescent modification material to 20-30°C, filter to remove large particle aggregates and catalytic residues, retain the filtrate, and concentrate the filtrate under reduced pressure to 1 / 3-1 / 2 of the original volume, then add it dropwise to the purified solvent, stir at 300-600 r / min for 30-90 min, then centrifuge at 6000-9000 r / min for 5-12 min, and collect the precipitate.

[0023] S4. The precipitate is washed sequentially with methanol, ethanol and deionized water until the pH of the washing solution is 6.8-7.3, then vacuum dried at 55-65℃ for 8-16 hours, ground for 20-50 minutes and passed through a 200-400 mesh sieve to obtain a m-nitroacetylene luminescent intermediate.

[0024] S5. The m-nitroacetylene luminescent intermediate is mixed with the film-forming regulator, and the film-forming solvent is added to prepare a dispersion with a mass concentration of 5-30 mg / mL. The mixture is stirred at 40-50℃ and 300-600 r / min for 2-8 h, and then filtered through a 0.22-0.45 μm organic filter membrane to obtain the m-nitroacetylene luminescent modified material.

[0025] Furthermore, in step S5, the m-nitroacetylene luminescent intermediate and the film-forming regulator are added to the film-forming solvent to prepare a dispersion with a mass concentration of 15-25 mg / mL, and stirred at 45°C and 500 r / min for 4-6 h.

[0026] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention uses a nano-silica-m-nitroacetylene triphenylamine composite monomer as the core functional component. First, the nano-silica is surface-activated and modified, then it is composited with the m-nitroacetylene triphenylamine structure, resulting in a relatively stable interfacial bond between the inorganic nano-component and the organic conjugated structure. This improves the compatibility and dispersion uniformity of nano-silica in organic systems, reduces nanoparticle aggregation, and ensures good dispersion stability of the resulting material in film-forming solvents.

[0027] 2. The present invention uses triphenylamine, carbazole and acetylene aromatic structures to form a conjugated luminescent system, which is beneficial to the uniform distribution of luminescent units in the material system and improves the fluorescence emission performance of the material. At the same time, by using a blocking agent to regulate the residual reaction sites after the coupling reaction, the adverse effects of the residual reaction sites on the stability and luminescent performance of the material can be reduced, so that the obtained material has a high fluorescence quantum yield and structural stability.

[0028] 3. This invention improves the leveling and film continuity of the dispersion by introducing a film-forming regulator, thereby reducing the surface roughness of the film and minimizing pinholes and local agglomeration. Simultaneously, the nano-silica inorganic framework and the organic conjugate structure form an organic-inorganic hybrid system, which improves the thermal stability of the material. This results in a material with excellent film uniformity, dispersion stability, fluorescence emission performance, and thermal stability, making it suitable for organic electroluminescent materials and related optoelectronic functional thin films. Attached Figure Description

[0029] Figure 1 Fourier transform infrared spectrum of nano-silica-m-nitroacetylene triphenylamine composite monomer obtained in Example 1 of this invention. Detailed Implementation

[0030] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] Preparation Example 1 Preparation of nano-silica-m-nitroacetylenetriphenylamine composite monomer: 1. Raw material weight parts: 4,4'-Dibromotriphenylamine: 25 parts; 3-Nitrophenylacetylene: 9 parts; Bis(triphenylphosphine)palladium dichloride: 0.20 parts; Cuprous iodide: 0.12 parts; Triethylamine: 55 parts; Anhydrous tetrahydrofuran: 150 parts; Anhydrous toluene: 80 parts; Nano silica: 6 parts; 3-Aminopropyltriethoxysilane: 2 parts; Deionized water: 40 parts; Anhydrous ethanol: 60 parts.

[0032] The nano-silica was purchased from Hubei Huifu Nanomaterials Co., Ltd., and is of the hydrophilic type HL-200 with a specific surface area of ​​200 m². 2 / g.

[0033] 2. Preparation method: A1. Take nano-silica and add it to a mixture of anhydrous ethanol and deionized water. Control the solid-liquid ratio of nano-silica to the mixture to be 1g:15-30mL. Stir and disperse at 30℃ and 700r / min for 35min to obtain a nano-silica dispersion. Add 3-aminopropyltriethoxysilane to the nano-silica dispersion and continue stirring at 500r / min for 10min. Then add glacial acetic acid at a dropping rate of 0.05 parts / min to adjust the pH of the system to 5.2, and react at 45℃ and 650r / min for 3.5h. After the reaction is completed, collect the solid by centrifugation at 8000r / min for 8min. Wash the obtained solid with anhydrous ethanol and deionized water in sequence until the pH of the last water washing solution is 6.5-7.2 to obtain wet nano-silica material.

[0034] A2. Add anhydrous tetrahydrofuran and anhydrous toluene to a reaction vessel and purge with nitrogen for 45 min. Add 25 parts of 4,4'-dibromotriphenylamine and stir at 25 °C and 500 r / min for 20 min. Then add 3-nitrophenylacetylene to the reaction system at a dropping rate of 0.10 parts / min and continue stirring for 20 min after the addition is complete. Add bis(triphenylphosphine)palladium dichloride, cuprous iodide and triethylamine to the reaction system, heat to 65 °C under nitrogen protection, and stir at 600 r / min for 12 h to obtain reaction solution A.

[0035] A3. Add the wet nano-silica material obtained in step A1 to the reaction solution A obtained in step A2; before adding, take another 1.0g of wet nano-silica material, dry it to constant weight at 105℃, determine the dry basis content of the wet nano-silica material, and calculate the amount of wet nano-silica material to be added based on the dry basis mass; based on the dry basis mass of the wet nano-silica material, control the solid-liquid ratio of its volume to the volume of reaction solution A to be 1g:40mL; perform a composite reaction at 70℃ and 650r / min for 6h to obtain an organic-inorganic hybrid composite system.

[0036] A4. Cool the organic-inorganic hybrid composite system obtained in step A3 to 25°C, filter to remove insoluble catalytic residues and large particulate impurities, and collect the solid phase by centrifugation at 8000 r / min for 8 min. The obtained solid is washed sequentially with ethyl acetate, acetone and n-hexane, with ethyl acetate used in 100 parts / wash twice, acetone used in 100 parts / wash twice, and n-hexane used in 120 parts / wash three times. Each wash is performed by stirring at 500 r / min for 10 min and then centrifuging. Subsequently, it is washed with deionized water until the pH of the final wash solution is 6.8-7.3. The washed solid is vacuum dried at 55°C for 12 h, ground for 35 min and passed through a 300-mesh sieve to obtain nano-silica-m-nitroacetylene triphenylamine composite monomer.

[0037] Depend on Figure 1 It can be seen that the infrared spectrum of the nano-silica-m-nitroacetylene triphenylamine composite monomer obtained in Example 1 is within 3400 cm⁻¹. -1 A broad absorption peak appears nearby, corresponding to the stretching vibrations of hydroxyl groups and adsorbed water on the surface of nano-silica; at 3050 cm⁻¹... -1 A stretching vibration peak of the aromatic ring CH appeared nearby, at 2920 cm⁻¹. -1 and 2850cm -1 The presence of alkyl CH stretching vibration peaks nearby indicates that aromatic structures such as triphenylamine and nitrobenzenethylene, as well as silane-modified organic segments, have been introduced into the material structure; at 2200 cm⁻¹ -1 The presence of a distinct absorption peak nearby can be attributed to the C≡C stretching vibration of the acetylene group, indicating that the meta-nitroacetylene structure participates in the recombination; at 1600 cm⁻¹... -1 The nearby absorption peak is related to the C=C stretching vibration of the aromatic ring skeleton, at 1520 cm⁻¹. -1 and 1340cm -1 The nearby absorption peaks correspond to the asymmetric and symmetric stretching vibrations of nitro-NO2, respectively, indicating that the nitrophenylacetylene structure exists in the functional monomer; the absorption peaks in the 1250-1000 cm⁻¹ range... -1 The region exhibits a strong absorption peak, which can be attributed to Si-O-Si framework vibrations and vibrations related to the organosilicon interface structure, at 800 cm⁻¹. -1 The nearby absorption peaks further indicate the presence of a nano-silica framework structure.

[0038] Comparative Preparation Example 1 The preparation of the nano-silica-m-nitroacetylene triphenylamine composite monomer was carried out by referring to the preparation method in Preparation Example 1, except that 2 parts by mass of 3-aminopropyltriethoxysilane were replaced with 2 parts by mass of 3-glycidyl etheroxypropyltrimethoxysilane, and the rest remained the same as in Preparation Example 1.

[0039] Comparative Preparation Example 2 The preparation of the nano-silica-m-nitroacetylene triphenylamine composite monomer was carried out by referring to the preparation method in Preparation Example 1, except that 8 parts by mass of 3-nitrophenylacetylene were replaced with 8 parts by mass of 1-acetyleno-4-nitrobenzene, and the rest remained the same as in Preparation Example 1.

[0040] Comparative preparation example 3 The preparation of the nano-silica-m-nitroacetylene triphenylamine composite monomer was carried out by referring to the preparation method in Preparation Example 1, except that 25 parts by mass of 4,4'-dibromotriphenylamine were replaced with 25 parts by mass of 4-bromotriphenylamine, and the rest remained the same as in Preparation Example 1.

[0041] Comparative preparation example 4 The preparation of the nano-silica-m-nitroacetylene triphenylamine composite monomer was carried out by referring to the preparation method in Preparation Example 1, except that 55 parts by mass of triethylamine were replaced with 55 parts by mass of N,N-diisopropylethylamine, and the rest remained the same as in Preparation Example 1.

[0042] Comparative preparation example 5 The preparation of the nano-silica-m-nitroacetylene triphenylamine composite monomer was carried out by referring to the preparation method in Preparation Example 1, except that 0.2 parts by mass of bis(triphenylphosphine)palladium dichloride was replaced with 0.2 parts by mass of tetra(triphenylphosphine)palladium, and the rest remained the same as in Preparation Example 1.

[0043] Comparative preparation example 6 The preparation of the nano-silica-m-nitroacetylene triphenylamine composite monomer was carried out by referring to the preparation method in Preparation Example 1, except that 6 parts by mass of nano-silica were replaced with 6 parts by mass of alumina, and the rest remained the same as in Preparation Example 1.

[0044] Example 1

[0045] Preparation of a m-nitroacetylene-based luminescent modified material: 1. Raw material weight parts: Nano-silica-m-nitroacetylene triphenylamine composite monomer: 20 parts, obtained from Preparation Example 1.

[0046] 3,6-Dibromo-9-octylcarbazole: 15 parts.

[0047] 1,4-Diethynylbenzene: 6.5 parts.

[0048] Sealing agent: 1.2 parts, which is phenylacetylene.

[0049] Palladium catalytic system: 0.25 parts, consisting of 0.07 parts palladium acetate and 0.18 parts triphenylphosphine.

[0050] Cuprous iodide: 0.15 parts.

[0051] Organic base: 60 parts, triethylamine.

[0052] Anhydrous organic solvent: 240 parts, consisting of 80 parts anhydrous toluene and 160 parts anhydrous tetrahydrofuran.

[0053] Film-forming regulator: 6 parts, which is polyvinylcarbazole.

[0054] Purification solvent: 300 parts, methanol.

[0055] The polyvinylcarbazole was purchased from Xi'an Sunlight Energy Technology Co., Ltd., model number 302007.

[0056] 2. Preparation method: S1. Take the nano-silica-m-nitroacetylene triphenylamine composite monomer obtained in Preparation Example 1, 3,6-dibromo-9-octylcarbazole, 1,4-diacetylbenzene, palladium acetate, triphenylphosphine, cuprous iodide, triethylamine, anhydrous tetrahydrofuran, and anhydrous toluene, and add them sequentially into a reaction vessel; purge with nitrogen for 45 min, and stir for 30 min at 25 °C and 600 r / min to obtain a deoxygenated dispersion.

[0057] S2. The deoxygenated dispersion obtained in step S1 is heated to 75°C and reacted for 14 hours under nitrogen protection and stirring at 600 r / min. Then, phenylacetylene is added dropwise to the reaction system at a rate of 0.06 parts / min. After the addition is completed, the reaction is continued at 75°C and 600 r / min for 4 hours to obtain the reaction solution of m-nitroacetylene luminescent modification material.

[0058] S3. Cool the reaction solution of the m-nitroacetylene-based luminescent modification material obtained in step S2 to 25°C, filter it through a 100-mesh sieve to remove large particle agglomerates, and retain the filtered reaction solution; concentrate the filtered reaction solution under reduced pressure at 45°C to 1 / 2 of the original volume, and then add it dropwise to 300 parts of methanol at a dropping rate of 1.5 mL / min, and stir at 25°C and 500 r / min for 60 min to precipitate; after precipitation, centrifuge at 8000 r / min for 8 min and collect the precipitate.

[0059] S4. The precipitate obtained in step S3 was washed sequentially with ethyl acetate, acetone, and deionized water. The amount of ethyl acetate was 150 parts per wash, and the washing was repeated twice. The amount of acetone was 150 parts per wash, and the washing was repeated twice. The amount of deionized water was 180 parts per wash, and the washing was repeated three times. Each wash was performed by stirring at 25°C and 500 r / min for 10 min, followed by centrifugation at 8000 r / min for 8 min, until the pH of the final wash solution was 7.1. The washed precipitate was then vacuum dried at 60°C for 12 h, ground for 35 min, and passed through a 300-mesh sieve to obtain a m-nitroacetylene luminescent intermediate.

[0060] S5. Take the m-nitroacetylene luminescent intermediate obtained in step S4 and polyvinylcarbazole as a film-forming regulator, add chlorobenzene and adjust the volume to 1300 mL to prepare a dispersion with a mass concentration of 20 mg / mL; stir at 45℃ and 500 r / min for 6 h, and then filter through a 0.45 μm organic filter membrane to obtain the m-nitroacetylene luminescent modified material.

[0061] Example 2

[0062] The preparation of a m-nitroacetylene-based luminescent modified material is carried out according to the preparation method in Example 1, except that the mass fraction of the nano-silica-m-nitroacetylene triphenylamine composite monomer is replaced with 30 parts, and the rest remains the same as in Example 1.

[0063] Example 3

[0064] The preparation of a meta-nitroacetylene-based luminescent modified material was carried out according to the preparation method in Example 1, except that the mass fraction of 3,6-dibromo-9-octylcarbazole was replaced with 22 parts, and the rest remained the same as in Example 1.

[0065] Example 4

[0066] The preparation of a meta-nitroacetylene-based luminescent modified material is carried out according to the preparation method in Example 1, except that the mass fraction of 1,4-diacetylene is replaced with 18 parts, and the rest remains the same as in Example 1.

[0067] Example 5

[0068] The preparation of a meta-nitroacetylene-based luminescent modified material is carried out according to the preparation method in Example 1, except that polyvinylcarbazole is replaced with polymethyl methacrylate, and the rest is the same as in Example 1.

[0069] Example 6

[0070] The preparation of a meta-nitroacetylene-based luminescent modified material is carried out according to the preparation method in Example 1, except that the catalytic system composed of palladium acetate and triphenylphosphine is replaced with bis(triphenylphosphine)palladium dichloride (PdCl2(PPh3)2), and the rest is the same as in Example 1.

[0071] Comparative Examples 1-6 The preparation of a m-nitroacetylene-based luminescent modified material is carried out by referring to the preparation method in Example 1, except that the nano-silica-m-nitroacetylene triphenylamine composite monomer is replaced with the nano-silica-m-nitroacetylene triphenylamine composite monomer prepared in Comparative Preparation Examples 1-6, and the rest is the same as in Example 1.

[0072] Comparative Example 7 The preparation of a m-nitroacetylene-based luminescent modified material is carried out according to the preparation method in Example 1, except that the nano-silica-m-nitroacetylene triphenylamine composite monomer is not added, and all other aspects are the same as in Example 1.

[0073] Performance testing: 1. Fluorescence emission performance test: The materials obtained from each example and comparative example were prepared into a 20 mg / mL dispersion with chlorobenzene. After stirring and filtration, the dispersion was spin-coated onto the surface of a quartz plate and dried to obtain the test film. The fluorescence quantum yield of the test film was determined using a fluorescence quantum yield testing system with an integrating sphere. The results are shown in Table 1.

[0074] 2. Dispersion stability test: The materials obtained from each example and comparative example were prepared into a 20 mg / mL dispersion with chlorobenzene. After stirring and filtration, the test dispersion was obtained. The changes in transmitted light or backscattered light signals of the samples were measured at 25℃ initially and after standing for 7 days using a static multiple light scattering stability analyzer. The results are shown in Table 1.

[0075] If transmittance retention rate is used as the characterization, the initial transmittance T0 and the transmittance T7 after standing for 7 days are measured at 550 nm using a UV-Vis spectrophotometer. The transmittance retention rate / % = T7 / T0 × 100%.

[0076] 3. Film Formation Performance Test: The dispersions obtained from each example and comparative example were spin-coated onto a cleaned and dried ITO glass substrate, and then vacuum dried to obtain a luminescent modified film. The surface roughness Rq of the film was measured using an atomic force microscope (AFM) with a scanning area of ​​5 μm × 5 μm; the film thickness was measured using a profilometer; and pinholes and agglomerations were observed using an optical microscope at 500x magnification, and the results were statistically analyzed for every 1 mm of film. 2 The number of pinholes within the range is shown in Table 1.

[0077] 4. Thermal stability test: The material dispersions obtained from each example and comparative example were taken, chlorobenzene was removed under reduced pressure, and the powder was dried under vacuum to obtain dry powder. Thermogravimetric analysis was performed under a nitrogen atmosphere, with a heating range of 30-600℃ and a heating rate of 10℃ / min. The 5% thermogravimetric temperature Td5 and the char residue at 600℃ were recorded. The results are shown in Table 1.

[0078] Table 1. Results of performance test data

[0079] As shown in Table 1, under the conditions described in this specification, the materials obtained in Examples 1-6 are generally superior to the comparative examples in terms of fluorescence quantum yield, dispersion stability, film uniformity, and thermal stability. In the examples, the nano-silica, after silanization treatment, is combined with the m-nitroacetylene triphenylamine structure, which helps improve the interfacial compatibility between the inorganic phase and the organic conjugated structure, reduces particle agglomeration, and allows the dispersion to maintain a high transmittance retention rate after standing. Simultaneously, the conjugated system composed of triphenylamine, carbazole, and acetylene aromatic structures facilitates the uniform distribution of luminescent units. The film-forming regulator improves the leveling and film continuity during spin coating, resulting in lower surface roughness and fewer pinholes in the film layers of the examples. In the comparative examples, changes in the silane coupling agent, nitrophenylacetylene structure, triphenylamine functionality, catalytic system, or inorganic components affect the grafting and recombination efficiency, conjugated structure integrity, and interfacial bonding state, leading to varying degrees of decrease in fluorescence quantum yield, dispersion stability, film quality, and thermal stability. Comparative Example 7 did not contain the nano-silica-m-nitroacetylene triphenylamine composite monomer, lacking the organic-inorganic synergistic structure and interface enhancement effect, thus its various properties were at a lower level.

[0080] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents, as shown in Table 1.

Claims

1. A m-nitroacetylene-based luminescent modified material, characterized in that, The product is prepared from the following raw materials in parts by weight: 12-30 parts of nano-silica-m-nitroacetylene triphenylamine composite monomer, 8-22 parts of 3,6-dibromo-9-octylcarbazole, 6-18 parts of 1,4-diacetylbenzene, 0.3-2.5 parts of blocking agent, 0.05-0.60 parts of palladium catalytic system, 0.03-0.35 parts of cuprous iodide, 20-70 parts of organic base, 160-320 parts of anhydrous organic solvent, 2-12 parts of film-forming regulator, and 120-450 parts of purification solvent; The nano-silica-m-nitroacetylene triphenylamine composite monomer is composed of the following raw material components: 15-35 parts of 4,4'-dibromotriphenylamine, 5-16 parts of 3-nitrophenylacetylene, 3-10 parts of nano-silica, and 1-5 parts of 3-aminopropyltriethoxysilane. The preparation method of the nano-silica-m-nitroacetylene triphenylamine composite monomer includes the following steps: A1. Add the nano-silica to a mixture of anhydrous ethanol and deionized water, controlling the solid-liquid ratio at 1g:15-30mL, and disperse for 20-50min at 25-35℃ and 500-900r / min; add the 3-aminopropyltriethoxysilane, and adjust the pH to 4.5-5.8 with glacial acetic acid, react at 35-55℃ for 2-5h, centrifuge, and wash until the pH of the washing solution is 6.5-7.2 to obtain wet nano-silica material; A2. Add 80-220 parts of anhydrous tetrahydrofuran and 40-120 parts of anhydrous toluene to a reaction vessel, purge with nitrogen for 30-60 min, add the 4,4'-dibromotriphenylamine and 3-nitrobenzyl acetylene, stir for 15-40 min, then add 0.05-0.40 parts of bis(triphenylphosphine)palladium dichloride, 0.03-0.25 parts of cuprous iodide and 25-90 parts of triethylamine, and react at 55-75℃ and 400-700 r / min for 8-18 h to obtain reaction solution A; A3. Add the wet nano-silica material to the reaction solution A; based on the dry weight of the wet nano-silica material, control the solid-liquid ratio of it to the reaction solution A to be 1g:25-60mL, and perform a composite reaction at 60-80℃ and 500-800r / min for 4-10h to obtain reaction solution B. A4. Cool the reaction solution B to 20-30℃, filter to remove insoluble matter, and collect the solid by centrifugation at 6000-9000 r / min for 5-12 min. Wash the obtained solid sequentially with organic detergent and deionized water until the pH of the washing solution is 6.5-7.2 when washing with deionized water for the last time. Then, vacuum dry at 45-65℃ for 8-16 h, grind for 20-50 min and pass through a 200-400 mesh sieve to obtain nano-silica-m-nitroacetylene triphenylamine composite monomer. In step A4, the organic detergent is one or more of methanol, ethanol, ethyl acetate, acetone, and n-hexane.

2. The m-nitroacetylene-based luminescent modified material according to claim 1, characterized in that, The sealing agent is selected from one or more of phenylacetylene, 4-tert-butylphenylacetylene, and trimethylsilylacetylene.

3. The m-nitroacetylene-based luminescent modified material according to claim 1, characterized in that, The palladium catalytic system is a catalytic system composed of palladium acetate and triphenylphosphine, wherein the mass ratio of palladium acetate to triphenylphosphine is 1:2.5-1:9.

5.

4. The m-nitroacetylene-based luminescent modified material according to claim 1, characterized in that, The organic base is one or more of triethylamine, diisopropylamine, diethylamine, piperidine, and N,N-diisopropylethylamine.

5. The m-nitroacetylene-based luminescent modified material according to claim 1, characterized in that, The anhydrous organic solvent is one or more of anhydrous tetrahydrofuran, anhydrous toluene, anhydrous N,N-dimethylformamide, and anhydrous 1,4-dioxane.

6. The m-nitroacetylene-based luminescent modified material according to claim 1, characterized in that, The film-forming regulator is one or more of polyvinylcarbazole, polymethyl methacrylate, and polystyrene.

7. The m-nitroacetylene-based luminescent modified material according to claim 1, characterized in that, The purification solvent is one or more of methanol, ethanol, n-hexane, petroleum ether, and ethyl acetate.

8. A method for preparing a m-nitroacetylene-based luminescent modified material as described in any one of claims 1-7, characterized in that, Includes the following steps: S1. Weigh the nano-silica-m-nitroacetylenetriphenylamine composite monomer, 3,6-dibromo-9-octylcarbazole, 1,4-diacetylbenzene, palladium catalytic system, cuprous iodide, organic base and anhydrous organic solvent, add the above raw materials to the reaction vessel, purge with nitrogen for 30-60 min, and stir for 20-40 min at 20-30℃ and 400-700 r / min to obtain a deoxygenated dispersion; S2. The deoxygenated dispersion is heated to 60-85℃ and reacted for 8-20 hours under nitrogen protection and stirring at 400-700 r / min. Then, the blocking agent is added at a rate of 0.03-0.15 parts / min and the reaction continues for 2-6 hours to obtain the reaction solution of m-nitroacetylene luminescent modified material. S3. Cool the reaction solution of the m-nitroacetylene-based luminescent modification material to 20-30°C, filter to remove large particle aggregates and catalytic residues, retain the filtrate, and concentrate the filtrate under reduced pressure to 1 / 3-1 / 2 of the original volume, then add it dropwise to the purified solvent, stir at 300-600 r / min for 30-90 min, then centrifuge at 6000-9000 r / min for 5-12 min, and collect the precipitate; S4. The precipitate is washed sequentially with methanol, ethanol and deionized water until the pH of the washing solution is 6.8-7.3, then vacuum dried at 55-65℃ for 8-16 hours, ground for 20-50 minutes and passed through a 200-400 mesh sieve to obtain a m-nitroacetylene luminescent intermediate. S5. The m-nitroacetylene luminescent intermediate is mixed with the film-forming regulator, and a film-forming solvent is added to prepare a dispersion with a mass concentration of 5-30 mg / mL. The mixture is stirred at 40-50℃ and 300-600 r / min for 2-8 h, and then filtered through a 0.22-0.45 μm organic filter membrane to obtain the m-nitroacetylene luminescent modified material.

9. The method for preparing a m-nitroacetylene-based luminescent modified material according to claim 8, characterized in that, In step S5, the m-nitroacetylene luminescent intermediate and the film-forming regulator are added to the film-forming solvent to prepare a dispersion with a mass concentration of 15-25 mg / mL, and stirred at 45°C and 500 r / min for 4-6 h.

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