A phenanthroline benzimidazole-structured polyimide single rare-earth ion coordinated full-spectrum luminescent material, its preparation method and application

Abstract

This application discloses a phenanthroline benzimidazole-structured polyimide single rare-earth ion coordination full-spectrum luminescent material, its preparation method, and its applications, belonging to the field of polymer luminescent material preparation technology. This phenanthroline benzimidazole-structured polyimide single rare-earth ion coordination full-spectrum luminescent material comprises a phenanthroline benzimidazole-structured polyimide, a rare-earth ion, and a β-diketone-structured small organic molecule ligand bound through coordination. This polymer single rare-earth coordination material retains the advantages of polyimide while exhibiting the characteristics of rare-earth ions (Ln... 3+ The addition of ) brings special optical properties, coordination polymers and rare earth ions Tb 3+ PI-Tb formed after coordination 3+ It can emit full-spectrum white light (CIE = (0.31, 0.35)) and exhibits excellent thermal stability and solubility.

Description

Technical Field

[0001] This application relates to a phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material, its preparation method and application, belonging to the field of polymer luminescent material preparation technology. Background Technology

[0002] Polymer light-emitting diodes (PLEDs) are a class of polymer-based devices that utilize polymers as the light-emitting material. Unlike organic light-emitting diodes (OLEDs), which employ inefficient vacuum thermal evaporation processes, PLEDs are manufactured using cost-effective techniques such as spin coating or inkjet printing. Currently, polymers used in PLEDs, including poly(terephthalic acid), polystyrene, and polyfluorene, are known for their low production costs and excellent processability. However, these polymers exhibit poor thermomechanical properties and are prone to photodegradation and oxidation, especially under harsh environmental conditions. These factors significantly limit the lifespan and reliability of PLED devices. Furthermore, achieving white light emission (full-light emission) using polymers remains a challenge.

[0003] Polyimides (PIs) are widely recognized for their superior thermal stability, chemical resistance, dimensional stability, and mechanical strength. However, in optoelectronics, they are typically used as transport layers, substrates, or support materials for light emission, and rarely as direct luminescent materials. Due to the strong intramolecular and intermolecular charge transfer (CT) interactions in polyimides (PIs), the CT (π-π*) state is the lowest excited state, resulting in low CT state oscillation intensity and low fluorescence quantum yield. Therefore, traditional aromatic PIs are generally non-luminescent. Current research on the luminescent properties of aromatic PIs generally involves introducing luminescent groups into the polymer chain structure. Other studies incorporate rare-earth metal complexes into PIs. Rare-earth elements are known for their unique electronic transitions, which produce unique emission spectra with high color purity, high luminous efficiency, and extended fluorescence lifetime. However, this pre-coordinated polymerization method is not conducive to obtaining high molecular weight PIs, and the subsequent film formation process becomes more challenging. Rare-earth metals can be introduced into PIs through post-polymerization coordination strategies, theoretically producing coordinated PIs with superior performance, while also obtaining pure and tunable color emission from the polymer.

[0004] To date, research on luminescent rare earth coordination polymers still faces many difficulties and bottlenecks: (1) In terms of synthesis, due to the large radius and strong charge of rare earth ions, the coordination number is large and the coordination configuration is relatively flexible during the coordination reaction. Therefore, it is difficult to control the synthesis of rare earth coordination polymers with specific structural characteristics, which is far from the goal of directional synthesis. (2) In terms of performance, the luminescent properties of rare earth coordination polymers largely depend on the process of sensitizing rare earth ions with organic ligands. External environmental factors, such as the vibration of water molecules, also have a great influence on the luminescence of rare earth coordination polymers. Therefore, how to select suitable organic ligands, control reaction conditions, or use post-modification methods to prepare rare earth coordination polymers with good luminescent properties still needs further research. (3) In terms of application, due to the relatively poor stability, solubility, and mechanical properties of rare earth coordination polymers, how to prepare rare earth coordination polymers into devices through process means to meet the needs of practical applications still needs further exploration. Summary of the Invention

[0005] To address the shortcomings of existing technologies for luminescent rare-earth coordination polymers, such as poor directional synthesis capabilities, insufficient emission spectral width, and relatively poor application stability and solubility, this application provides a phenanthroline benzimidazole-structured polyimide single rare-earth ion coordinated full-spectrum luminescent material, its preparation method, and its applications. The phenanthroline benzimidazole structure is introduced to impart excellent rare-earth metal ion coordination capabilities. Based on this, PI-Tb is generated through the reaction of a β-diketone small molecule ligand with rare-earth ion sensitizing properties with the polyimide molecule phenanthroline benzimidazole ligand. 3+ Coordinated polyimide. Tb 3+ Red light (Tb) emission under organic ligand sensitization 3+ (5D0→7F5 electronic transition of ions) and Tb 3+ The blue-to-red shift (550-615 nm) in polymer emission occurs due to charge transfer resulting from coordination with the phenanthroline structure in the polymer. Because of the intramolecular cross-linking of the coordinated polyimide, the cross-linking enhances intermolecular charge transfer, thus broadening the emission spectrum to cover a wide wavelength range of 470-700 nm (full-spectrum emission). The rigid structure of phenanthroline benzimidazole imparts good thermal and chemical stability to the material, while the twisted structure increases the free volume of the polymer, enhances its solubility, and improves its processability.

[0006] The technical solution adopted in this application is as follows:

[0007] According to one aspect of this application, a phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material is provided, comprising a phenanthroline benzimidazole structured polyimide, a rare earth ion, and a β-diketone structured organic small molecule ligand bound by coordination.

[0008] The phenanthroline benzimidazole-structured polyimide has the structure shown in Formula I:

[0009]

[0010] Where Ar is a residue of the dianhydride monomer;

[0011] M is selected from C6-C 40 At least one of the arylene groups;

[0012] 0.5 < n ≤ 1, n + m = 1;

[0013] The rare earth ions are selected from Tb ions;

[0014] The β-diketone organic small molecule ligand is selected from α-thienyltrifluoroacetone.

[0015] Optionally, the phenanthroline benzimidazole-structured polyimide single rare-earth ion coordinated full-spectrum luminescent material has the structure of the general formula shown in Formula II:

[0016]

[0017] Wherein, Ln represents rare earth ions, and Ligand represents small molecule ligands with a β-diketone structure;

[0018] Ar represents a residue of the dianhydride monomer;

[0019] M is selected from C6-C 40 At least one of the arylene groups;

[0020] 0.5 < n ≤ 1, n + m = 1;

[0021] The rare earth ions are selected from Tb ions;

[0022] The β-diketone organic small molecule ligand is selected from α-thienyltrifluoroacetone.

[0023] The applicant's research revealed that, in full-spectrum luminescence, only Tb can achieve full-spectrum emission (i.e., so-called white light emission), while rare earth ions such as Eu, Ce, Yb, Sm, and Gd cannot achieve the full-spectrum emission characteristics of this application. Furthermore, small organic molecules with β-diketone structures can only achieve full-spectrum emission (i.e., so-called white light emission) using α-thienyltrifluoroacetone.

[0024] Optionally, the molar ratio of the rare earth ions to the N atoms in the phenanthroline benzimidazole-structured polyimide is 0.025 to 0.5:1;

[0025] Optionally, the β-diketone organic small molecule ligand is selected from α-thienyltrifluoroacetone.

[0026] Optionally, Ar is selected from any of the groups in the structure shown in Formula III;

[0027]

[0028] Optionally, M is selected from any of the groups in the structure shown in Formula IV;

[0029]

[0030] Optionally, the phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material exhibits a fluorescence emission peak in the wavelength range of 490–630 nm under 393 nm light excitation.

[0031] Optionally, the glass transition temperature of the phenanthroline benzimidazole structured polyimide is greater than or equal to 294°C.

[0032] Optionally, the initial decomposition temperature (T) of the phenanthroline benzimidazole structured polyimide is... d5％ ) Greater than or equal to 504℃.

[0033] Optionally, the carbon residue of the phenanthroline benzimidazole structured polyimide is greater than or equal to 50%.

[0034] Optionally, the molecular weight of the phenanthroline benzimidazole-structured polyimide is greater than or equal to 20,000 g / mol.

[0035] Optionally, the glass transition temperature of the phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material is greater than or equal to 250°C.

[0036] Optionally, the initial decomposition temperature (T0) of the phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material is... d5％ ) Greater than or equal to 380℃.

[0037] Optionally, the carbon residue of the phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material is greater than or equal to 55%.

[0038] According to another aspect of this application, a method for preparing the above-mentioned phenanthroline benzimidazole structured polyimide single rare earth ion coordination full-spectrum luminescent material is provided. First, 2,9-bis(1-hydro-benzimidazole-2-yl)-1,10-phenanthroline is prepared using 1,10-phenanthroline-2,9-diacid and o-phenylenediamine as raw materials. Then, the 2,9-bis(1-hydro-benzimidazole-2-yl)-1,10-phenanthroline and 1-fluoro-4-phenylenediamine are used... The dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline was prepared by nucleophilic substitution reaction using nitro-2-trifluoromethylbenzene as a monomer under the action of a catalyst. Subsequently, the dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline was reacted with a catalyst and a reducing agent. A reduction reaction was carried out in the presence of an aromatic diamine monomer, 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazole-yl))bis(3-(trifluoromethyl)aniline, to prepare a polyimide with a phenanthroline-benzimidazole structure. Then, the 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazole-yl))bis(3-(trifluoromethyl)aniline was polymerized with an aromatic diamine and an aromatic dianhydride to prepare a polyimide with a phenanthroline-benzimidazole structure. Next, under an inactive atmosphere, a small molecule ligand with a rare earth metal chloride salt and a β-diketone structure was reacted in an alkaline mixed solution to prepare an organic small molecule rare earth complex. Finally, under an inactive atmosphere, the small molecule rare earth metal complex and the polyimide polymer containing the phenanthroline-benzimidazole structure were coordinated in an organic solvent to prepare a phenanthroline-benzimidazole structure polyimide single rare earth ion coordination full-spectrum luminescent material.

[0039] The method for preparing a phenanthroline benzimidazole-structured polyimide single rare-earth ion coordinated full-spectrum luminescent material of this application includes the following steps:

[0040] S1. A monomer mixture containing 1,10-phenanthroline-2,9-dicarboxylicacid and o-phenylenediamine is added to polyphosphate and reacted in reaction I to obtain 2,9-bis(1H-benzimidazol-2-yl)-1,10-phenanthroline.

[0041] S2. A mixture containing 2,9-bis(1-(4-nitro-2-(trifluoromethyl)-phenyl)-1,10-phenanthroline, 1-fluoro-4-nitro-2-trifluoromethylbenzene, catalyst I, and solvent I is reacted with reaction II to give the dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline. In step S2, the product is prepared by nucleophilic substitution of the monomers under the action of a catalyst.

[0042] S3. Under an inactive atmosphere, a mixture containing the dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline, catalyst II, reducing agent, and solvent II is reacted with reaction III to obtain the diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazol-yl))bis(3-(trifluoromethyl)aniline(4,4'-((1,10-phenanthroline-2,9-diyl)-bis(1H-benzo[d]imidazole-2,1-diyl))-bis(3-(trifluoromethyl)-aniline)). This step S3 involves a reduction reaction in the presence of a catalyst and a reducing agent to prepare the product.

[0043] S4. Under an inactive atmosphere, a mixture containing diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1H-benzo[d]imidazole-2,1-diyl))bis(3-(trifluoromethyl)aniline(4,4'-((1,10-phenanthroline-2,9-diyl)-bis(1H-benzo[d]imidazole-2,1-diyl))-bis(3-(trifluoromethyl)-aniline)), a dianhydride monomer containing an Ar structure, a diamine monomer containing an M structure, and solvent III is reacted in IV-a. Then, catalyst III is added to the product, and the reaction continues in IV-b. Finally, ethanol is added to the product to form a precipitate, yielding the phenanthroline benzimidazole polyimide.

[0044] S5. Add rare earth metal chlorides and β-diketone organic small molecule ligands to an alkaline mixture, react IV, and obtain small molecule rare earth complexes.

[0045] S6. Mix the phenanthroline benzimidazole structured polyimide and the small molecule rare earth complex in solvent IV for coordination to obtain the phenanthroline benzimidazole structured polyimide single rare earth ion coordination full-spectrum luminescent material.

[0046] Optionally, in step S1, the molar ratio of 1,10-phenanthroline-2,9-dicarboxylic acid and o-phenylenediamine is 1:2.0 to 2.2.

[0047] Optionally, in step S1, the conditions for reaction I include: a reaction temperature of 200–240°C and a reaction time of 5–8 h.

[0048] Optionally, step S1 further includes pouring the reaction solution into an ice-water mixture after reaction I, adjusting the pH to 8.5-9.5 with ammonia to form a precipitate, and washing and drying the precipitate.

[0049] Optionally, in step S1, the process diagram of reaction I is as follows:

[0050]

[0051] Optionally, in step S2, the molar ratio of 2,9-bis(1-hydro-benzimidazol-2-yl)-1,10-phenanthroline and 1-fluoro-4-nitro-2-trifluoromethylbenzene is 1:2.0 to 2.2.

[0052] Optionally, in step S2, the conditions for reaction II include: a reaction temperature of 80–120°C and a reaction time of 12–24 h.

[0053] Optionally, step S2 also includes, after reaction II, pouring the reaction solution into water to form a precipitate, and washing and drying the precipitate.

[0054] Optionally, in step S2, the process diagram of reaction II is as follows:

[0055]

[0056] Optionally, in step S2, catalyst I is selected from at least one of potassium carbonate, cesium carbonate, and calcium carbonate.

[0057] Optionally, in step S2, solvent I is selected from at least one of N-methylpyrrolidone, N-dimethylformamide, and N-dimethylacetamide.

[0058] Optionally, in step S3, catalyst II is a 5% dry palladium on carbon catalyst (Pb / C catalyst, with Pd loading of 5%).

[0059] Optionally, in step S3, the amount of catalyst II is 8-12% of the weight of the dinitro compound.

[0060] Optionally, in step S3, the reducing agent is 85% hydrazine hydrate (85% N2H4·H2O).

[0061] Optionally, in step S3, the amount of reducing agent used is 5 to 10 times the weight of the dinitro compound.

[0062] Optionally, in step S3, the conditions for reaction III include: a reaction temperature of 80–120°C and a reaction time of 12–24 h.

[0063] Optionally, in step S3, the mixture containing the dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline, catalyst II, reducing agent, and solvent II is obtained by adding the reducing agent dropwise to the mixture containing the dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline, catalyst II, and solvent II.

[0064] Optionally, step S3 further includes filtering to remove catalyst II after reaction III, rotary evaporating to remove solvent I, and then drying the resulting solid powder.

[0065] Optionally, in step S3, solvent II is selected from at least one of ethanol, N,N-dimethylformamide, and N,N-dimethylacetamide.

[0066] Optionally, in step S4, the ratio of the diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazol-yl))bis(3-(trifluoromethyl)aniline, the dianhydride monomer containing the Ar structure, and the diamine monomer containing the M structure is 1:1:1.

[0067] Optionally, in step S4, catalyst III is selected from isoquinoline.

[0068] Optionally, in step S4, the conditions for reaction IV-a include: a reaction temperature of 80℃ to 90℃ for 1 to 2 hours.

[0069] Optionally, in step S4, the reaction mixture containing the diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1H-benzo[d]imidazole-2,1-diyl))bis(3-(trifluoromethyl)aniline(4,4'-((1,10-phenanthroline-2,9-diyl)-bis(1H-benzo[d]imidazole-2,1-diyl))-bis(3-(trifluoromethyl)-aniline)), the diamine monomer containing the M structure, and solvent III is stirred and dissolved in an inactive atmosphere at 80–100°C for 0.5–2 h. After dissolution, the dianhydride monomer containing the Ar structure is added to obtain the mixture.

[0070] Optionally, in step S4, the conditions for reaction IV-b include: reacting at 150℃~160℃ for 2~4h, and then raising the temperature to 190℃~200℃ for 12~18h.

[0071] Optionally, step S4 further includes gradually adding ethanol to the reaction solution after reaction IV-b to form a fibrous precipitate, followed by filtration, water washing, alcohol washing, and drying.

[0072] Optionally, in step S4, solvent III is selected from at least one of m-cresol, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone.

[0073] Optionally, in step S5, the molar ratio of rare earth metal chloride salt to organic small molecule ligands with β-diketone structure is 1:3 to 3.1.

[0074] Optionally, in step S5, the conditions for reaction V include: heating to 60°C, reacting at this temperature for 0.5 to 4 hours, and then naturally cooling under continuous stirring until the precipitate is completely formed.

[0075] Optionally, step S5 further includes filtering the precipitate after reaction V, dissolving the precipitate with benzene, adding n-hexane and mixing, letting it stand for 8-16 hours, filtering, and drying the solid product.

[0076] Optionally, in step S5, the process diagram of reaction V is as follows:

[0077]

[0078] Optionally, in step S5, the pH of the alkaline mixture is greater than or equal to 8, and the alkaline mixture includes a mixture of ethanol and water, wherein the volume ratio of ethanol to water is 1:8 to 20.

[0079] Optionally, in step S6, the molar ratio of the small molecule rare earth metal complex to the phenanthroline imidazole group in the phenanthroline benzimidazole structured polyimide is 0.1 to 0.3:1.

[0080] Optionally, in step S6, the conditions for reaction VI include: a reaction temperature of 50–120°C, a reaction time of 8–15 h, and continuous stirring during the reaction.

[0081] Optionally, step S6 further includes concentrating the reaction solution by rotary evaporation after reaction VI, then adding it dropwise to ethanol to induce precipitation, and washing the precipitate with water, alcohol, and drying.

[0082] Optionally, in step S6, the process diagram of reaction VI is as follows:

[0083]

[0084] Optionally, solvent IV is selected from at least one of tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone.

[0085] According to another aspect of this application, at least one of the above-described phenanthroline benzimidazole structure polyimide single rare earth ion coordination full-spectrum luminescent materials or phenanthroline benzimidazole structure polyimide single rare earth ion coordination full-spectrum luminescent materials prepared by the above method is provided in polymer luminescent materials.

[0086] The beneficial effects that this application can produce include:

[0087] The phenanthroline benzimidazole-structured polyimide single rare-earth ion coordinated full-spectrum luminescent material provided in this application exhibits a fluorescence emission peak in the wavelength range of 490–630 nm under 393 nm light excitation. This coordination polymer and rare-earth ion Tb 3+ PI-Tb formed after coordination 3+ It can emit full-spectrum white light (CIE = (0.31, 0.35)); the glass transition temperature of this luminescent material is above 294℃, and the initial decomposition temperature (T) is... d5％ The glass transition temperature of the phenanthroline benzimidazole structured polyimide single rare earth ion coordination full-spectrum luminescent material is above 250℃, with a residual carbon content above 50% and an initial decomposition temperature (T0). The glass transition temperature is above 504℃, the glass transition temperature is above 250℃, and the initial decomposition temperature is above 504℃. d5％ At temperatures above 380℃, the residual carbon content is above 55%; the molecular weight of the phenanthroline benzimidazole structured polyimide reaches above 20,000 g / mol. Compared with currently studied organic light-emitting materials, the polymer material prepared in this application exhibits significantly improved solubility, thermal properties, and light-emitting properties, possessing potential commercial value and lower production costs, enabling large-scale production and application. Attached Figure Description

[0088] Figure 1 The NMR spectrum of 2,9-bis(1-hydro-benzimidazol-2-yl)-1,10-phenanthroline prepared in the embodiments of this application.

[0089] Figure 2 The NMR spectrum of the dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline prepared in the embodiments of this application.

[0090] Figure 3 The NMR spectrum of the diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazol-yl))bis(3-(trifluoromethyl)aniline prepared in the embodiments of this application.

[0091] Figure 4 The NMR spectrum of PI-1, a polyimide polymer with a phenanthroline benzimidazole structure prepared in the embodiments of this application.

[0092] Figure 5 GPC test results of PI-1, a polyimide polymer with a phenanthroline benzimidazole structure prepared for the embodiments of this application.

[0093] Figure 6 The fluorescence spectrum of the phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material prepared in the embodiments of this application is shown. Detailed Implementation

[0094] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0095] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0096] Unless otherwise specified, all test methods are standard and all instrument settings are those recommended by the manufacturer.

[0097] Data testing conditions and methods in this application embodiment:

[0098] Nuclear magnetic resonance spectroscopy (NMR): 1 H NMR was performed on a Bruker AVANCE III 400MHz NMR instrument, with tetramethylsilane (TMS) as an internal standard and DMS O-d6 as a solvent.

[0099] Fourier Transform Infrared (FT-IR) Measurement: FT-IR spectra were obtained using a VERTEX 70 at 4000 cm⁻¹. -1 up to 400cm -1 Tested within the wavelength range.

[0100] Fluorescence spectroscopy test: Fluorescence spectra were tested on an FS920 (450W xenon lamp) fluorescence spectrometer.

[0101] Gel permeation chromatography (GPC): Gel permeation chromatography was performed using a Waters 1515 gel permeation chromatograph with tetrahydrofuran (THF) as the mobile phase.

[0102] Differential scanning calorimetry (DSC): Measured using a Q20 under nitrogen atmosphere at a heating rate of 10 K / min.

[0103] Thermogravimetric analysis (TG): Measured using a STA449C analyzer under nitrogen atmosphere at a heating rate of 10 K / min.

[0104] According to one embodiment of this application, a method for preparing a phenanthroline benzimidazole-structured polyimide single rare-earth ion coordinated full-spectrum luminescent material includes:

[0105] (1) 2,9-Bis(1H-benzimidazol-2-yl)-1,10-phenanthroline was prepared by reacting 1,10-phenanthroline-2,9-dicarboxylic acid and o-phenylenediamine in polyphosphoric acid;

[0106] (2) Using 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline and 1-fluoro-4-nitro-2-trifluoromethylbenzene as monomers, a nucleophilic substitution reaction was carried out in the presence of a catalyst to prepare the dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline;

[0107] (3) The dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1H-benzimidazole-2-yl-1,10-phenanthroline was reduced in the presence of a catalyst and a reducing agent to prepare the diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1H-benzo[d]imidazole-yl))bis(3-(trifluoromethyl)aniline(4,4'-((1,10-phenanthroline-2,9-diyl)-bis(1H-benzo[d]imidazole-2,1-diyl))-bis(3-(trifluoromethyl)-aniline));

[0108] (4) Under an inactive atmosphere, the diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1H-benzo[d]imidazole-2,1-diyl))bis(3-(trifluoromethyl)aniline(4,4'-((1,10-phenanthroline-2,9-diyl)-bis(1H-benzo[d]imidazole-2,1-diyl))-bis(3-(trifluoromethyl)-aniline)), the dianhydride monomer containing the Ar structure, and the diamine monomer containing the M structure are mixed in an organic solvent and polymerized under the action of a catalyst to obtain the phenanthroline benzimidazole structure polyimide;

[0109] (5) Prepare small molecule rare earth complexes by reacting rare earth metal chloride salts and small molecule ligands with β-diketone structures in an alkaline mixed solution under an inactive atmosphere.

[0110] (6) Under an inactive atmosphere, the small molecule rare earth metal complex obtained in step 5 and the polyimide polymer containing phenanthroline benzimidazole structure obtained in step 4 are coordinated in an organic solvent to prepare the polyimide rare earth ion coordination luminescent polymer.

[0111] Example 1

[0112] The synthesis of 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazol-yl))bis(3-(trifluoromethyl)aniline in steps S1 to S3 is as follows.

[0113] Step S1: Under an inert gas atmosphere, 2.68 g of 1,10-phenanthroline-2,9-diacid and 2.27 g of o-phenylenediamine were added to 25 ml of polyphosphoric acid. The reaction was carried out at 220 °C for 6 h. After the reaction was completed, the mixture was cooled to 120 °C, and the reaction solution was poured into 300 ml of an ice-water mixture. The pH of the mixture was adjusted to 9 with ammonia. The precipitate was obtained by filtration, washed three times with hexane, and dried in a vacuum drying oven at 80 °C for 6 h to obtain the product 2,9-bis(1-hydro-benzimidazol-2-yl)-1,10-phenanthroline. The NMR spectrum is shown below. Figure 1 As shown;

[0114] Step S2: Under an inert gas atmosphere, 4.12 g of 2,9-bis(1-hydro-benzimidazol-2-yl)-1,10-phenanthroline, 2.76 g of anhydrous potassium carbonate, and 4.39 g of 1-fluoro-4-nitro-2-trifluoromethylbenzene prepared in Step 1 were added to 40 ml of DMF. The mixture was reacted at 95 °C for 15 h. After the reaction was completed, the mixture was cooled to room temperature, and the reaction solution was poured into 200 ml of deionized water. The precipitate was obtained by filtration, washed three times with hexane, and dried in a vacuum drying oven at 80 °C for 6 h to obtain the product 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline. The NMR spectrum is shown below. Figure 2 As shown;

[0115] Step S3: Under an inert gas atmosphere, 0.99 g of the dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline and 0.10 g of 10% Pd / C catalyst (Pd loading 10%) were added to 35 ml of ethanol. Then, 0.8 ml of hydrazine hydrate was added dropwise to the above reaction system. The reaction was carried out at 85 °C for 12 h. After the reaction was completed, the mixture was cooled to room temperature, the catalyst was removed by filtration, and the solvent was removed by rotary evaporation to obtain a solid powder. The powder was dried in a vacuum drying oven at 80 °C for 6 h to obtain the diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazol-yl))bis(3-(trifluoromethyl)aniline, NMR spectrum as shown below. Figure 3 As shown.

[0116] Step S4: Synthesis of phenanthroline benzimidazole structured polyimide polymer

[0117] Under an inert atmosphere, 0.15 g of 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazol-yl))bis(3-(trifluoromethyl)aniline and 0.04 g of 4,4'-diaminodiphenyl ether (ODA) were rapidly added to a three-necked flask, followed by approximately 3 mL of m-cresol as a solvent. The mixture was stirred at 80 °C for 1 h under a nitrogen atmosphere to dissolve the reactants. 0.21 g of bisphenol A diether dianhydride (BPADA) was then added to the mixture. The reaction temperature was increased to 150 °C and stirred continuously. After 3 hours, 0.15 mL of isoquinoline was added to the reaction system as a dehydrating agent and catalyst. The temperature was then increased to 200 °C, and the reaction was continued for 12 h with stirring. After cooling, the reaction solution was gradually poured into ethanol, resulting in a large amount of fibrous precipitate. After filtration, the precipitate was washed with copious amounts of water and ethanol, and the dried product was designated PI-1. The NMR spectrum is shown below. Figure 4 As shown, the GPC test results are as follows: Figure 5 As shown.

[0118] Step S5: Synthesis of small molecule rare earth complexes

[0119] Under an inert gas atmosphere, 1.33 g (6 mmol) of 2-thienylformyltrifluoroacetone (TTA) was dissolved in 30 mL of anhydrous ethanol. Then, 6 mL of NaOH (1N) aqueous solution and 10 mL of TbCl3·6H2O (2 mmol) anhydrous ethanol solution were added sequentially to the TTA anhydrous ethanol solution. 200 mL of distilled water was then added, and the mixture was heated to 60 °C. After stirring, it was cooled to room temperature, and a precipitate formed. The precipitate was filtered, and the solid was dissolved in 60 mL of benzene. 200 mL of n-hexane was added, and the mixture was allowed to stand overnight at room temperature. After filtration, it was dried under vacuum at 60 °C for 48 h to obtain a light yellow solid, which was designated as the small molecule rare earth complex Tb(TTA)3·2H2O.

[0120] Step S6: Synthesis of phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material

[0121] 0.19 g of polymer PI-1 was dissolved in 10 ml of tetrahydrofuran (THF). A small-molecule rare earth complex containing Ln(TTA)3·2H2O was added to the reaction mixture at a molar ratio of 10% for the phenanthroline imidazole group. The reaction system was continuously stirred at a stable temperature of 60 °C for 15 h. After the reaction was complete, the reaction solution was concentrated by rotary evaporation and then slowly added dropwise to ethanol to induce precipitation. The precipitate was washed with water and ethanol, and the dried product was designated as PI-Ligned-Tb. 3+ -10%, fluorescence spectrum as follows Figure 6 As shown.

[0122] Example 2

[0123] Steps S1 to S5 are the same as in Example 1, except that step S6 is:

[0124] 0.19 g of polymer PI-1 was dissolved in 10 ml of tetrahydrofuran (THF). A small molecule rare earth complex containing Ln(TTA)3·2H2O was added to the reaction mixture at a molar ratio of 20% for the phenanthroline imidazole group. The reaction system was continuously stirred at a stable temperature of 60 °C for 15 h. After the reaction was complete, the reaction solution was concentrated by rotary evaporation and then slowly added dropwise to ethanol to induce precipitation. The precipitate was washed with water and ethanol, and the dried product was designated as PI-Ligned-Tb. 3+ -20%, fluorescence spectrum as Figure 6 As shown.

[0125] Example 3

[0126] Steps S1 to S5 are the same as in Example 1, except that step S6 is:

[0127] 0.19 g of polymer PI-1 was dissolved in 10 ml of tetrahydrofuran (THF). A small-molecule rare earth complex containing Ln(TTA)3·2H2O was added to the reaction mixture at a molar ratio of 30% for the phenanthroline imidazole group. The reaction system was continuously stirred at a stable temperature of 60 °C for 15 h. After the reaction was completed, the reaction solution was concentrated by rotary evaporation and then slowly added dropwise to ethanol to induce precipitation. The precipitate was washed with water and ethanol, and the dried product was designated as PI-Ligned-Tb. 3+ -30%, fluorescence spectrum as Figure 6 As shown.

[0128] Example 4

[0129] Steps S1-S3 and S5-S6 are the same as in Example 1, except that step S4 is:

[0130] Under an inert gas atmosphere, 0.15 g of 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazol-yl))bis(3-(trifluoromethyl)aniline and 0.04 g of 4,4'-diaminodiphenyl ether (ODA) were rapidly added to a three-necked flask, followed by approximately 3 mL of m-cresol as a solvent. The mixture was stirred at 80 °C for 1 h under a nitrogen atmosphere to dissolve the reactants. 0.18 g of hexafluoroisopropylphthalic anhydride (6FDA) was then added to the mixture. The reaction temperature was increased to 150 °C and stirred continuously. After 3 hours, 0.15 mL of isoquinoline was added to the reaction system as a dehydrating agent and catalyst. The temperature was then increased to 200 °C, and the reaction was continued for 12 h with stirring. After cooling, the reaction solution was gradually poured into ethanol, resulting in a large amount of fibrous precipitate. After filtration, the precipitate was washed with copious amounts of water and ethanol, and the dried product was designated as PI-2.

[0131] Example 5

[0132] Steps S1-S3 and S5-S6 are the same as in Example 1, except that step S4 is:

[0133] Under an inert gas atmosphere, 0.15 g of 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazol-yl))bis(3-(trifluoromethyl)aniline and 0.037 g of 4,4'-diaminobiphenyl were rapidly added to a three-necked flask, followed by approximately 3 mL of m-cresol as a solvent. The mixture was stirred at 80 °C for 1 h under a nitrogen atmosphere to dissolve the reactants. 0.18 g of hexafluoroisopropylphthalic anhydride (6FDA) was added to the mixture. The reaction temperature was increased to 150 °C and stirred continuously. After 3 hours, 0.15 mL of isoquinoline was added to the reaction system as a dehydrating agent and catalyst. The temperature was then increased to 200 °C, and the reaction was continued for 12 h with stirring. After cooling, the reaction solution was gradually poured into ethanol, resulting in a large amount of fibrous precipitate. After filtration, the precipitate was washed with copious amounts of water and ethanol, and the dried product was designated PI-3.

[0134] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material, characterized in that, This includes small organic molecule ligands with phenanthroline benzimidazole structure that are bound through coordination, rare earth ions, and β-diketone structure; The phenanthroline benzimidazole-structured polyimide has the structure shown in Formula I: Formula I; Where Ar is a residue of the dianhydride monomer; M is selected from C6-C 40 At least one of the arylene groups; 0.5 < n ≤ 1, n + m = 1; The rare earth ions are selected from Tb ions; The β-diketone organic small molecule ligand is selected from α-thienyltrifluoroacetone.

2. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, The phenanthroline benzimidazole-structured polyimide single rare-earth ion coordinated full-spectrum luminescent material has the structure shown in Formula II: Formula II; In this context, Ln represents rare earth ions, and Ligand represents small molecule ligands with a β-diketone structure.

3. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, The molar ratio of rare earth ions to N atoms in the phenanthroline benzimidazole-structured polyimide is 0.025~0.5:

1.

4. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, Ar is selected from any one of the groups in the structure shown in Formula III; Formula III.

5. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, M is selected from any one of the groups in the structure shown in Formula IV; Formula IV.

6. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material exhibits a fluorescence emission peak in the wavelength range of 490~630 nm under 393 nm light excitation.

7. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, The glass transition temperature of the phenanthroline benzimidazole structured polyimide is greater than or equal to 294 °C.

8. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, The initial decomposition temperature of the phenanthroline benzimidazole structured polyimide is greater than or equal to 504 °C.

9. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, The carbon residue of the phenanthroline benzimidazole structured polyimide is greater than or equal to 50%.

10. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, The phenanthroline benzimidazole structured polyimide has a molecular weight greater than or equal to 20,000 g / mol.

11. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, The glass transition temperature of the polyimide single rare earth ion coordinated full-spectrum luminescent material with phenanthroline benzimidazole structure is greater than or equal to 250 °C.

12. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, The initial decomposition temperature of the phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material is greater than or equal to 380℃.

13. The phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to claim 1, characterized in that, The carbon residue of the phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material is greater than or equal to 55%.

14. A method for preparing the phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to any one of claims 1 to 13, characterized in that, Includes the following steps: S1. A monomer mixture containing 1,10-phenanthroline-2,9-diacid and o-phenylenediamine is added to polyphosphoric acid and reacted in reaction I to obtain 2,9-bis(1-hydro-benzimidazol-2-yl)-1,10-phenanthroline. S2. A mixture containing 2,9-bis(1-hydro-benzimidazol-2-yl)-1,10-phenanthroline and 1-fluoro-4-nitro-2-trifluoromethylbenzene, catalyst I, and solvent I is reacted with reaction II to give the dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline; S3. Under an inactive atmosphere, a mixture containing the dinitro compound 2,9-bis(1-(4-nitro-2-trifluoromethyl)-phenyl)-1-hydro-benzimidazol-2-yl-1,10-phenanthroline, catalyst II, reducing agent, and solvent II is reacted with reaction III to obtain the diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazol-yl))bis(3-(trifluoromethyl)aniline; S4. Under an inactive atmosphere, a mixture containing diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazole-yl))bis(3-(trifluoromethyl)aniline, a dianhydride monomer containing an Ar structure, a diamine monomer containing an M structure, and solvent III is reacted in IV-a. Then, catalyst III is added to the product, and the reaction continues in IV-b. Finally, ethanol is added to the product to form a precipitate, yielding the phenanthroline benzimidazole polyimide. S5. Add rare earth metal chlorides and β-diketone organic small molecule ligands to an alkaline mixture, react IV, and obtain small molecule rare earth complexes. S6. Mix the phenanthroline benzimidazole structured polyimide and the small molecule rare earth complex in solvent IV for coordination to obtain the phenanthroline benzimidazole structured polyimide single rare earth ion coordination full-spectrum luminescent material.

15. The preparation method according to claim 14, characterized in that, In step S1, the molar ratio of 1,10-phenanthroline-2,9-dicarboxylic acid and o-phenylenediamine is 1:2.0~2.

2.

16. The preparation method according to claim 14, characterized in that, In step S1, the conditions for reaction I include: a reaction temperature of 200~240℃ and a reaction time of 5~8h.

17. The preparation method according to claim 14, characterized in that, In step S2, the molar ratio of 2,9-bis(1-hydro-benzimidazol-2-yl)-1,10-phenanthroline and 1-fluoro-4-nitro-2-trifluoromethylbenzene is 1:2.0~2.

2.

18. The preparation method according to claim 14, characterized in that, In step S2, the conditions for reaction II include: a reaction temperature of 80~120℃ and a reaction time of 12~24h.

19. The preparation method according to claim 14, characterized in that, In step S2, catalyst I is selected from at least one of potassium carbonate, cesium carbonate, and calcium carbonate.

20. The preparation method according to claim 14, characterized in that, In step S2, solvent I is selected from at least one of N-methylpyrrolidone, N,N-dimethylformamide, and N,N-dimethylacetamide.

21. The preparation method according to claim 14, characterized in that, In step S3, catalyst II is a 5% dry palladium on carbon catalyst.

22. The preparation method according to claim 14, characterized in that, In step S3, the amount of catalyst II is 8-12% of the weight of the dinitro compound.

23. The preparation method according to claim 14, characterized in that, In step S3, the reducing agent is 85% hydrazine hydrate.

24. The preparation method according to claim 14, characterized in that, In step S3, the amount of reducing agent used is 5 to 10 times the weight of the dinitro compound.

25. The preparation method according to claim 14, characterized in that, In step S3, the conditions for reaction III include: a reaction temperature of 80~120℃ and a reaction time of 12~24h.

26. The preparation method according to claim 14, characterized in that, In step S3, solvent II is selected from at least one of ethanol, N,N-dimethylformamide, and N,N-dimethylacetamide.

27. The preparation method according to claim 14, characterized in that, In step S4, the ratio of the diamine monomer 4,4'-((1,10-phenanthroline-2,9-diyl)bis(1-hydro-benzimidazol-yl))bis(3-(trifluoromethyl)aniline, the dianhydride monomer containing the Ar structure, and the diamine monomer containing the M structure is 1:1:

1.

28. The preparation method according to claim 14, characterized in that, In step S4, catalyst III is selected from isoquinoline.

29. The preparation method according to claim 14, characterized in that, In step S4, the conditions for reaction IV-a include: reaction at 80℃~90℃ for 1~2h.

30. The preparation method according to claim 14, characterized in that, In step S4, the conditions for reaction IV-b include: a reaction at 150℃~160℃ for 2~4h, followed by raising the temperature to 190℃~200℃ for 12~18h.

31. The preparation method according to claim 14, characterized in that, In step S4, solvent III is selected from at least one of m-cresol, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone.

32. The preparation method according to claim 14, characterized in that, In step S5, the molar ratio of rare earth metal chloride to β-diketone organic small molecule ligand is 1:3~3.

1.

33. The preparation method according to claim 14, characterized in that, In step S5, the conditions for reaction IV include: heating to 60°C, reacting at this temperature for 0.5 to 4 hours, and then naturally cooling under continuous stirring until the precipitate is completely formed.

34. The preparation method according to claim 14, characterized in that, In step S5, the pH of the alkaline mixture is greater than or equal to 8, and the alkaline mixture includes a mixture of ethanol and water, wherein the volume ratio of ethanol to water is 1:8~20.

35. The preparation method according to claim 14, characterized in that, In step S6, the molar ratio of the small molecule rare earth complex to the phenanthroline imidazole group in the polyimide with the phenanthroline benzimidazole structure is 0.1~0.3:

1.

36. The preparation method according to claim 14, characterized in that, In step S6, the reaction conditions include: a reaction temperature of 50~120℃ and a reaction time of 8~15h.

37. The preparation method according to claim 14, characterized in that, Solvent IV is selected from at least one of tetrahydrofuran, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone.

38. The application of the phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material according to any one of claims 1 to 13 or the phenanthroline benzimidazole structured polyimide single rare earth ion coordinated full-spectrum luminescent material prepared according to any one of claims 14 to 37 in polymer luminescent materials.

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