Porous organic ultra-long-life room-temperature phosphorescent material created by hydrogen bond induced self-assembly, preparation method and application

Abstract

The invention discloses a porous organic ultra-long-life room-temperature phosphorescent material created by hydrogen bond induced self-assembly as well as a preparation method and application thereof, and relates to the technical field of high-molecular functional materials. The method comprises the following steps: adding a monomer, a cross-linking agent, phosphorescent molecules and an initiator into an organic solvent, and uniformly mixing to obtain a precursor solution; injecting the precursor solution into a mold, and reacting at 60-70 DEG C for 6-12 hours to obtain organic gel; placing the organic gel in deionized water for dialysis for 5-8 days, completing recombination of hydrogen bonds in the hydrogel through a solvent exchange process to induce in-situ self-assembly of polymer chain segments, and then removing moisture through natural drying or freeze drying to obtain the porous organic room-temperature phosphorescent material with ultra-long service life. The color-adjustable porous organic ultra-long-life room-temperature phosphorescent material is prepared through free radical polymerization, and has the advantages that the raw materials are easy to obtain, the operation is simple, complicated post-treatment is not needed, the biocompatibility is good, the nano porous microstructure is uniform, and the like.

Description

Technical Field

[0001] The invention relates to the technical field of polymer functional materials, and in particular to a porous organic ultra-long-life room-temperature phosphorescent material created by hydrogen bond-induced self-assembly, a preparation method and an application thereof. Background Art

[0002] Room temperature phosphorescence (RTP) materials generally have the characteristics of relatively large Stokes shift and long phosphorescence lifetime, which promotes their application in biological imaging, sensors, information encryption and organic light-emitting display materials. Compared with traditional room temperature phosphorescent materials, room temperature phosphorescence based on organic materials has gradually gained attention due to its advantages of lower cost, low toxicity, biocompatibility, and re-modification and processing.

[0003] However, there are still some problems that need to be solved for organic room temperature phosphorescent materials, such as the slow radiative transition rate of triplet excitons, which are easily quenched by substances such as oxygen and water; the strong non-radiative transition due to the high degree of freedom of the molecules, and the weak spin-orbit coupling ability. It is a common and feasible idea to restrict the movement of fluorescent molecules to reduce non-radiative transitions and enhance the room temperature phosphorescence of materials.

[0004] At present, the matrix binds fluorescent molecules to construct organic room temperature phosphors, mainly through methods that enhance the interaction between functionalized fluorescent molecules and polymer matrix molecules, such as chemical crosslinking, host-guest interaction, hydrogen bonding, etc. This method usually has complicated and difficult operation steps. At the same time, since it involves post-modification functionalization of fluorescent molecules, it is also accompanied by a sharp increase in costs and more refined requirements for structural design. For doping systems, fluorescent molecules are mainly mixed with polymers through physical blending, which has problems such as single phosphorescent color, difficulty in molding, and existence in powder form, which is difficult to functionalize.

[0005] Therefore, it is very necessary to explore a strategy for polymer-based porous organic room-temperature phosphorescent materials that are highly universal, simple to operate, low-cost, and have ultra-long phosphorescence afterglow and tunable phosphorescence color. Summary of the invention

[0006] In view of the deficiencies in the above-mentioned background technology, the present invention mainly solves the problems of complex operation, short life and afterglow time, single color, rough microstructure, etc. in the preparation of room temperature phosphorescent materials disclosed in the prior art. The present invention provides a porous organic ultra-long life room temperature phosphorescent material created by hydrogen bond induced self-assembly and a preparation method and application. The method prepares a color-adjustable porous organic ultra-long life room temperature phosphorescent material by free radical polymerization, has the advantages of easy raw material availability, simple operation, no need for complex post-processing, good biocompatibility, uniform nanoporous microstructure, etc., and has great application potential in the fields of optical recording, data encryption, OLED, biological imaging, etc.

[0007] The first object of the present invention is to provide a method for preparing a porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly, comprising the following steps: Adding monomers, crosslinking agents, phosphorescent molecules, and initiators into an organic solvent and mixing them evenly to obtain a precursor solution; The precursor solution is injected into the mold and reacted at 60-70°C for 6-12 h to obtain an organogel; The organic gel is placed in deionized water for dialysis for 5 to 8 days, and the reorganization of hydrogen bonds inside the hydrogel is completed through the solvent exchange process to induce the in-situ self-assembly of polymer segments, and then the water is removed by natural drying or freeze drying to obtain a porous organic ultra-long-lifetime room temperature phosphorescent material; The monomers include carboxyl monomers and amide bond monomers.

[0008] Preferably, the carboxyl monomer includes methacrylic acid and / or acrylic acid; the amide bond monomer includes one or more of N-vinyl caprolactam, N-isopropylacrylamide, and methacrylamide.

[0009] Preferably, the phosphorescent molecules are one or more of biphenyl, naphthalene, anthracene, phenanthrene and pyrene.

[0010] Preferably, the cross-linking agent is N,N'-methylenebisacrylamide; the initiator is azobisisobutyronitrile, potassium persulfate or ammonium persulfate; and the organic solvent is dimethyl sulfoxide.

[0011] Preferably, the molar ratio of the carboxyl monomer to the amide bond monomer is (60-90): (40-10).

[0012] Preferably, the amount of the crosslinking agent is 1-5.0% of the molar amount of the monomer; the amount of the initiator added is 1-3% of the total mass of the monomer and the crosslinking agent; the amount of the organic solvent added is the volume number when the total molar concentration of the monomer and the crosslinking agent is 3-5 mol / L.

[0013] Preferably, the mold includes two stacked glass plates and a silicone sheet clamped between the two glass plates, wherein a through hole is provided in the middle of the silicone sheet; the through hole and the glass plates at both ends form a closed cavity for injecting the precursor solution; wherein the thickness of the silicone sheet is 0.5~2 mm.

[0014] Preferably, the dialysis process is continued until the mass of the hydrogel no longer changes.

[0015] The second object of the present invention is to provide a porous organic ultra-long life room temperature phosphorescent material created by hydrogen bond induced self-assembly.

[0016] The third object of the present invention is to provide a hydrogen bond induced self-assembly to create porous organic ultra-long life room temperature phosphorescent material for use in biological imaging, sensors, information encryption or organic light-emitting display materials.

[0017] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a porous organic ultra-long life room temperature phosphorescent material created by hydrogen bond induced self-assembly, a preparation method and an application. The present invention prepares an organic gel by first completing free radical polymerization of monomers and crosslinking agents in an organic solvent. Secondly, the prepared organic gel is completely immersed in deionized water. As DMSO is replaced into water, the reorganization of hydrogen bonds inside the hydrogel will also induce the occurrence of a self-assembly process, so that the polymer tightly encapsulates the phosphorescent molecules and inhibits non-radiative transitions. After removing the water therein, a porous room temperature phosphorescent material with an ultra-long phosphorescent life can be obtained. In addition, the life time and phosphorescent color of the hydrogel can be regulated by changing the type and content of the phosphorescent molecules.

[0018] The present invention controls the self-assembly process in the hydrogel by inducing the recombination process of the hydrogen bond donor (-COOH) and the hydrogen bond acceptor (-CONH), so that the polycyclic and condensed ring aromatic hydrocarbon phosphorescent molecules, such as biphenyl, naphthalene, anthracene, phenanthrene and pyrene, can be tightly wrapped by the polymer network to inhibit the non-radiative transition of the phosphorescent molecules, and prepare a room temperature phosphorescent material with an ultra-long phosphorescent lifetime, and the phosphorescent lifetime can reach up to 2.2 s and the afterglow time can reach 15 s. In addition, the method of creating a porous organic ultra-long life room temperature phosphorescent material by hydrogen bond induced self-assembly of the present invention is not simple to determine. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 PMAN-BP 1.0% Fluorescence and phosphorescence emission spectra; Figure 2 The fluorescence emission spectra of porous room temperature phosphorescent materials with different biphenyl contents; Figure 3 The phosphorescence emission spectra of porous room temperature phosphorescent materials with different biphenyl contents; Figure 4 is the phosphorescence lifetime of porous room temperature phosphorescent materials with different biphenyl contents; Figure 5 PMAN-Phe 1.0% Fluorescence and phosphorescence emission spectra; Figure 6 is the fluorescence emission spectra of porous room temperature phosphorescent materials with different phenanthrene contents; Figure 7 The phosphorescence emission spectra of porous room temperature phosphorescent materials with different phenanthrene contents; Figure 8 The phosphorescence lifetime of porous room temperature phosphorescent materials with different phenanthrene contents; Fig. 9 For PMAN-Py 1.0% Fluorescence and phosphorescence emission spectra; Fig.10 is the fluorescence emission spectra of porous room temperature phosphorescent materials with different pyrene contents; Fig.11 is the phosphorescence emission spectra of porous room temperature phosphorescent materials with different pyrene contents; Fig.12 is the phosphorescence lifetime of porous room temperature phosphorescent materials with different pyrene contents at an emission wavelength of 590 nm; Fig.13 is the phosphorescence lifetime of porous room temperature phosphorescent materials with different pyrene contents at an emission wavelength of 655 nm; Fig.14 This is the SEM image of the porous room temperature phosphorescent material with 1% content of biphenyl, phenanthrene and pyrene; Fig.15 This is the BET diagram of the porous room temperature phosphorescent material with a biphenyl content of 1%; Fig.16 This is the afterglow image of the porous room temperature phosphorescent material with a biphenyl, phenanthrene and pyrene content of 1%. DETAILED DESCRIPTION

[0020] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the present invention is further described below in conjunction with specific embodiments and drawings, but the embodiments are not intended to limit the present invention.

[0021] The present invention aims at the problems that the spin coupling quantum number of the existing phosphorescent material molecules is low, the molecular thermal motion causes non-radiative transitions, and the influence of quenchers such as water and oxygen makes phosphorescence difficult to achieve, the phosphorescence lifetime is short, and the light intensity is weak. In particular, the non-radiative transitions caused by the movement of phosphorescent molecules reduce the phosphorescence intensity of the material, or even quench the phosphorescence. In the present invention, an organic gel with a three-dimensional network structure is first prepared by free radical polymerization in an organic solvent; then the organic gel is completely immersed in a large amount of deionized water to replace the DMSO inside the gel, and the hydrogen bond recombination inside the hydrogel is completed. By regulating the ratio of different hydrogen bond donors and acceptors, the strength of the hydrogen bonds inside the hydrogel can be controlled, and then the strength of the hydrogel can be controlled. In addition, the hydrogen bond recombination inside the hydrogel induces a self-assembly process, which is accompanied by phase separation processes of varying degrees, forming a large number of nanopore structures, and finally preparing a series of porous organic room temperature phosphorescent materials with adjustable pore sizes. The reason why the porous material has room temperature phosphorescent properties and shows tolerance to oxygen, which distinguishes it from other common room temperature phosphorescent materials, is that the preparation of the organic gel is first completed by polymerization in DMSO. The strong hydrogen bond reorganization during the solvent exchange process enables the polymer to tightly bind the hydrophobic phosphorescent molecules together.

[0022] In order to achieve the above object, the first aspect of the present invention provides a method for preparing a porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly, comprising the following steps: Adding monomers, crosslinking agents, phosphorescent molecules, and initiators into an organic solvent and mixing them evenly to obtain a precursor solution; The precursor solution is injected into the mold and reacted at 60-70°C for 6-12 h to obtain an organogel; The organic gel is placed in deionized water for dialysis for 5 to 8 days, and the reorganization of hydrogen bonds inside the hydrogel is completed through the solvent exchange process to induce the in-situ self-assembly of polymer segments, and then the water is removed by natural drying or freeze drying to obtain a porous organic ultra-long-lifetime room temperature phosphorescent material; The monomers include carboxyl monomers and amide bond monomers.

[0023] The present invention firstly dissolves hydrogen bond donor monomers, hydrogen bond acceptor monomers, phosphorescent molecules, a chemical crosslinking agent and an initiator in DMSO and mixes them uniformly, then adds them into a glass mold to generate free radicals through thermal initiation, and then polymerizes to prepare an organic gel. Then, the prepared organic gel is completely immersed in deionized water, and as DMSO is replaced by water, the hydrogen bonds inside the hydrogel induce a self-assembly process, so that the polymer tightly encapsulates the phosphorescent molecules to inhibit non-radiative transitions, and after removing the water therein, a room temperature phosphorescent material with a porous ultra-long phosphorescent life can be obtained.

[0024] The present invention induces in-situ self-assembly by constructing hydrogen bonds to load fluorescent substances to prepare porous organic room temperature phosphorescent materials with ultra-long afterglow time and adjustable luminescent color. The raw materials include carboxyl monomers, amide bond monomers, phosphorescent molecules, crosslinking agents, initiators and organic solvents.

[0025] The carboxyl monomer includes methacrylic acid and / or acrylic acid; the amide bond monomer includes one or more of N-vinyl caprolactam, N-isopropylacrylamide, and methacrylamide.

[0026] The phosphorescent molecules are one or more of biphenyl, naphthalene, anthracene, phenanthrene and pyrene.

[0027] The cross-linking agent is N,N'-methylenebisacrylamide; the initiator is azobisisobutyronitrile, potassium persulfate or ammonium persulfate; and the organic solvent is dimethyl sulfoxide.

[0028] The molar ratio of the carboxyl monomer to the amide bond monomer is (60-90): (40-10).

[0029] The amount of the crosslinking agent used is 1-5.0% of the molar amount of the monomer; the amount of the initiator added is 1%-3% of the total mass of the monomer and the crosslinking agent; the amount of the organic solvent added is the volume number when the total molar concentration of the monomer and the crosslinking agent is 3-5 mol / L.

[0030] The mold includes two stacked glass plates and a silicone sheet sandwiched between the two glass plates, wherein a through hole is provided in the middle of the silicone sheet; the through hole and the glass plates at both ends form a closed cavity for injecting a precursor solution; wherein the thickness of the silicone sheet is 0.5-2 mm.

[0031] The dialysis process is continued until the quality of the hydrogel no longer changes.

[0032] In one embodiment, a method for preparing a porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly includes: Adding monomers, crosslinking agents, phosphorescent molecules, and initiators into an organic solvent and mixing them evenly to obtain a precursor solution; The precursor solution is injected into the mold and reacted at 65-80°C for 6-12 h to obtain an organogel; The organogel is placed in deionized water for 5 to 8 days for dialysis. The reorganization of hydrogen bonds inside the hydrogel is completed through the solvent exchange process to induce the in-situ self-assembly of polymer segments, thereby achieving effective loading of polycyclic and condensed-ring aromatic hydrocarbon phosphorescent molecules. The water is then removed by natural drying or freeze drying to prepare a porous organic room temperature phosphorescent material with ultra-long afterglow time and adjustable phosphorescent color. The mold includes two stacked glass plates and a silicone sheet sandwiched between the two glass plates, wherein a through hole is provided in the middle of the silicone sheet; the through hole and the glass plates at both ends form a closed cavity for injecting a precursor solution; wherein the thickness of the silicone sheet is 0.5-2 mm.

[0033] The dialysis process is continued until the quality of the hydrogel no longer changes.

[0034] The hydrogen bond donor monomer includes methacrylic acid (MAA) and acrylic acid (AA); The hydrogen bond acceptor monomers include N-vinyl caprolactam (NVCL), N-isopropylacrylamide (NIPAM), and methacrylamide (MAAm); The molar ratio of the hydrogen bond donor monomer to the hydrogen bond acceptor monomer is (60-90): (40-10).

[0035] The crosslinking agent is N,N'-methylenebisacrylamide (MBA); the amount of the crosslinking agent is 1-2.5% of the total molar amount of methacrylic acid, acrylic acid and N-vinyl caprolactam; The phosphorescent molecules are specifically biphenyl, phenanthrene, pyrene, etc.; the content of the phosphorescent molecules is 0.1%-2.0% of the total molar amount of methacrylic acid, acrylic acid, and N-vinyl caprolactam; The initiator is azobisisobutyronitrile (AIBN) or potassium persulfate (KPS) or ammonium persulfate (APS); the added amount of the initiator is 1-5% of the total mass of methacrylic acid, acrylic acid, N-vinyl caprolactam and the crosslinking agent.

[0036] The organic solvent is dimethyl sulfoxide (DMSO) and N,N-dimethylformamide (DMF); the amount of the organic solvent added is a volume in which the total molar concentration of methacrylic acid, acrylic acid, N-vinyl caprolactam and N,N'-methylenebisacrylamide is 3 mol / L.

[0037] Wherein, the amount of the cross-linking agent is 1% of the total molar amount of the monomer. The addition of the cross-linking agent mainly provides chemical cross-linking for the organogel, so that it can obtain a complete organogel under the condition of hydrogen bond destruction. With the increase of the amount of cross-linking agent added in the hydrogel, the polymer chain will also be more firmly bound, which undoubtedly promotes the aggregation of the polymer and then increases the binding of the phosphorescent molecules to enhance phosphorescence. Without affecting the purpose of the invention, the amount of the cross-linking agent added can be expanded to 2.0%, 3.0%, 4.0%, 5.0%, etc.

[0038] The initiator is a thermal initiator, and the amount added is 1% of the total mass of MAA, AA, NVCL and MBA. The addition of the initiator is mainly to provide free radicals for the free radical polymerization of the monomers of the hydrogel. When at a certain temperature, the initiator will provide a large number of active polymerization sites, causing the occurrence of free radical polymerization. The initiator can be selected from potassium persulfate (KPA), ammonium persulfate (APS), etc. The amount of the initiator can be increased to 2%, 3%, 4%, 5%, etc.

[0039] In one embodiment, a method for creating a porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly includes the following process: Step 1: Add methacrylic acid (MAA), acrylic acid (AA), N-vinyl caprolactam (NVCL), N,N'-methylenebisacrylamide (MBA), phosphorescent molecule biphenyl (BP), and thermal initiator azobisisobutyronitrile (AIBN) into a certain amount of dimethyl sulfoxide (DMSO), stir magnetically to dissolve and mix evenly to prepare a precursor solution; Step 2: Inject the prepared precursor solution into a mold consisting of a glass plate and a silicone sheet, react and polymerize at 65°C for 12 hours, and open the glass mold after returning to room temperature. Place the prepared organogel in a large amount of deionized water and dialyze it for 5-7 days until the mass of the hydrogel no longer changes, and the hydrogel can be obtained.

[0040] Among them, in the configuration of the precursor solution, the addition ratio of methacrylic acid, acrylic acid and N-vinyl caprolactam is 60:20:20 (molar ratio), and the hydrogel is recorded as PMAN; The amount of phosphorescent molecule biphenyl (BP) added to the precursor solution is 1% of the total molar amount of methacrylic acid, acrylic acid and N-vinyl caprolactam; The amount of crosslinking agent N,N'-methylenebisacrylamide (MBA) added to the precursor solution is 1% of the total molar amount of methacrylic acid, acrylic acid and N-vinylcaprolactam; The amount of initiator azobisisobutyronitrile (AIBN) added to the precursor solution is 1% of the total mass of methacrylic acid, acrylic acid, N-vinyl caprolactam and N,N'-methylenebisacrylamide; The added mass of the solvent dimethyl sulfoxide (density ρ = 1.1 g / ml) is such that the total molar amount of methacrylic acid, acrylic acid, N-vinyl caprolactam and N,N'-methylenebisacrylamide is maintained at 3 mol / L; Step 3: After fully completing the solvent replacement, the hydrogel is removed of moisture by freeze drying or natural drying to obtain a porous organic ultra-long-lifetime room temperature phosphorescent material created by hydrogen bond induced self-assembly.

[0041] In some embodiments of the present invention, the amount of the crosslinking agent added is 1% of the total amount of the monomers, and the amount of DMSO used is an amount that can make the total concentration of the monomers and the crosslinking agent 3 mol / L. The molar ratio of methacrylic acid, acrylic acid, and N-vinyl caprolactam monomers can be 80:0:20, 70:10:20, and 60:20:20. According to the present invention, firstly, after the monomer, phosphorescent molecule, chemical crosslinker and initiator are fully dissolved in the solvent DMSO, the precursor solution is injected into the glass plate mold. The free radical polymerization reaction is carried out by thermal initiation under anaerobic conditions to obtain an organic gel. Then the prepared gel is immersed in deionized water to fully exchange the solvent until the quality of the hydrogel no longer changes, and finally the water therein is removed to complete the preparation of the porous organic ultra-long life room temperature phosphorescent material. Among them, the monomer can be purchased directly from the market, and after purification, the inhibitor is removed. In the present invention, the above-mentioned polymerization reaction needs to be carried out under anaerobic conditions to prevent oxygen from quenching the free radicals generated during the polymerization process. The anaerobic condition adopts the inert gas nitrogen to be filled into the system precursor solution. In some embodiments of the present invention, preferably according to the molar ratio involved in the above technical scheme, the monomer, phosphorescent molecule, chemical crosslinker, initiator and solvent are mixed and dissolved, stirred evenly, and nitrogen is blown into the mixed solution for 5 minutes, and then the obtained solution is transferred to a glass mold of a specific shape, and polymerized at 65°C for 12 hours to obtain an organic gel. Then, the desired hydrogel is obtained by sufficient solvent exchange at room temperature. Finally, the water therein is removed to complete the preparation of the porous organic ultra-long-life room temperature phosphorescent material.

[0042] The preparation method of the porous organic ultra-long-lifetime room temperature phosphorescent material provided by the present invention is simple, convenient, easy to implement, and conducive to large-scale production.

[0043] It should be noted that the porous material provided by the present invention has room temperature phosphorescence properties and exhibits tolerance to oxygen, which is different from other common room temperature phosphorescent materials. The reason is that the preparation of the organic gel is first completed by polymerization in DMSO. The strong hydrogen bond reorganization during the solvent exchange process enables the polymer to tightly bind the hydrophobic phosphorescent molecules together, significantly inhibiting the radiation transition of the phosphorescent molecules. The hydrophobicity and strong intermolecular forces make it tolerant to oxygen and moisture, so that the phosphorescent molecules without phosphorescence emission under normal conditions will show organic room temperature phosphorescence properties with long afterglow, long life and strong phosphorescence. In the present invention, due to the generation of assemblies of different particle sizes during the hydrogen bond reorganization process, the phosphorescent emission exhibits excitation-dependent properties within a certain range.

[0044] The second aspect of the present invention provides a porous organic ultra-long-lifetime room-temperature phosphorescent material created by hydrogen bond-induced self-assembly.

[0045] It should be noted that the experimental methods used in the present invention are all conventional methods unless otherwise specified; the reagents and materials used are all commercially available unless otherwise specified.

[0046] Example 1 This embodiment provides a method for creating a porous organic ultra-long life room temperature phosphorescent material by hydrogen bond induced self-assembly, using an organic room temperature phosphorescent material PMAN-BP with a biphenyl molar content of 1%. 1.0% Take the example of biphenyl as an example, the subscript indicates the amount of phosphorescent molecule added, and the process is as follows: Take the purchased methacrylic acid MAA (1.00 g, 11.62 mmol), acrylic acid AA (0.279 g, 3.87 mmol), N-vinyl caprolactam NVCL (0.539 g, 3.87 mmol) according to the molar ratio of 60:20:20, and add the phosphorescent molecule BP (0.03 g, 0.194 mmol), crosslinker MBA (0.03 g) and initiator azobisisobutyronitrile AIBN (0.019 g) and dissolve them in the solvent DMSO (7.17 g). Nitrogen was blown for 10 minutes, and then the precursor solution was transferred and injected into a homemade rectangular glass mold, and polymerized at 65°C for 12 h to obtain an organic gel. After returning to room temperature, the glass mold was opened and the prepared organic gel was dialyzed in a large amount of deionized water for 5-7 days. After removing the water contained in the obtained glassy hydrogel, a porous organic ultra-long-lifetime room temperature phosphorescent material created by hydrogen bond induced self-assembly can be obtained.

[0047] Example 2 The same as Example 1, except that the addition amount of phosphorescent molecule biphenyl (BP) was 0.5%, 2.0%, and 5.0%, respectively, to prepare porous organic ultra-long life room temperature phosphorescent material PMAN-BP 0.5% 、PMAN-BP 2.0% 、PMAN-BP 5.0% .

[0048] Example 3 The same as Example 1, except that the amount of phosphorescent molecule phenanthrene (Phe) added was 1.0% to prepare the porous organic ultra-long life room temperature phosphorescent material PMAN-Phe 1.0% .

[0049] Example 4 The same as Example 1, except that the addition amount of phosphorescent molecule phenanthrene (Phe) was 0.5%, 2.0%, and 5.0%, respectively, to prepare porous organic ultra-long life room temperature phosphorescent material PMAN-Phe 0.5% 、PMAN-Phe 2.0% 、PMAN-Phe5.0% .

[0050] Example 5 The same as Example 1, except that the amount of phosphorescent molecule pyrene (Py) added was 1.0% to prepare the porous organic ultra-long life room temperature phosphorescent material PMAN-Py 1.0% .

[0051] Example 6 The same as Example 1, except that the addition amount of phosphorescent molecule pyrene (Py) was 0.5%, 2.0%, and 5.0%, respectively, to prepare porous organic ultra-long life room temperature phosphorescent material PMAN-Py 0.5% 、PMAN-Py 2.0% 、PMAN-Py 5.0% .

[0052] In order to illustrate the relevant performance of the porous organic ultra-long-lifetime room temperature phosphorescent material created by hydrogen bond induced self-assembly provided by the present invention, it is described in conjunction with the accompanying drawings.

[0053] Figure 1 PMAN-BP 1.0% Fluorescence and phosphorescence emission spectra; the figure shows the organic room temperature phosphorescent material prepared in Example 1, wherein Fluo and Phos represent the fluorescence and phosphorescence spectral curves of the material, respectively. When the biphenyl content is 1.0 mol %, the material exhibits fluorescence emission in the range of 300-350 nm and phosphorescence emission in the range of 450-500 nm after being excited.

[0054] Figure 2 : is the fluorescence emission spectrum of porous room temperature phosphorescent materials with different biphenyl contents; this figure is the organic room temperature phosphorescent material prepared in Example 2, wherein FL represents the fluorescence spectrum. As shown in the figure, the fluorescence of the emission spectrum does not change the wavelength range as the biphenyl content changes, but the fluorescence intensity decreases as the biphenyl content increases.

[0055] Figure 3 Figure 2 is the phosphorescence emission spectrum of porous room temperature phosphorescent materials with different biphenyl contents; the figure is the organic room temperature phosphorescent material prepared in Example 2, wherein PL represents the phosphorescence spectrum. As shown in the figure, the wavelength range of the phosphorescence emission spectrum does not change with the change of biphenyl content, but the phosphorescence intensity increases in the process of increasing the content from 0.5% to 1.0%, and the phosphorescence intensity decreases when the biphenyl content continues to increase to 5.0%.

[0056] Figure 4is the phosphorescence lifetime of porous room temperature phosphorescent materials with different biphenyl contents; the figure is the phosphorescence lifetime spectrum of the organic room temperature phosphorescent materials prepared in Examples 1 and 2 after being excited by 254 nm ultraviolet rays. When the biphenyl contents are 0.5%, 1.0%, 2.0% and 5.0% respectively, the phosphorescence lifetimes are 1.493 s, 2.211 s, 1.185 s and 1.107 s.

[0057] Figure 5 PMAN-Phe 1.0% Fluorescence and phosphorescence emission spectra; the figure shows the organic room temperature phosphorescent material prepared in Example 3, wherein Fluo and Phos represent the fluorescence and phosphorescence spectral curves of the material, respectively. When the phenanthrene content is 1.0 mol %, the material exhibits fluorescence emission in the range of 350-420 nm and phosphorescence emission in the range of 450-550 nm after being excited.

[0058] Figure 6 : is the fluorescence emission spectrum of porous room temperature phosphorescent materials with different phenanthrene contents; this figure is the organic room temperature phosphorescent material prepared in Example 4, wherein FL represents the fluorescence spectrum. As shown in the figure, the wavelength range of the phosphorescence emission spectrum does not change with the change of phenanthrene content, but the fluorescence intensity changes from a lower wavelength (370 nm) to a higher wavelength (420 nm) with the increase of phenanthrene content.

[0059] Figure 7 The figure is the phosphorescence emission spectrum of porous room temperature phosphorescent materials with different phenanthrene contents; the figure is the organic room temperature phosphorescent material prepared in Example 4, where PL represents the phosphorescence spectrum, and the phosphorescence intensity gradually increases with the increase of phenanthrene content.

[0060] Figure 8 is the phosphorescence lifetime of porous room temperature phosphorescent materials with different phenanthrene contents; the figure is the phosphorescence lifetime spectrum of the organic room temperature phosphorescent materials prepared in Examples 3 and 4 after being excited by 310 nm ultraviolet rays. When the phenanthrene contents are 0.5%, 1.0%, 2.0% and 5.0% respectively, the phosphorescence lifetimes are 1.065 s, 1.045 s, 0.964 s and 0.568 s.

[0061] Fig. 9 For PMAN-Py 1.0% Fluorescence and phosphorescence emission spectra; The figure shows the organic room temperature phosphorescent material prepared in Example 5, wherein Fluo and Phos represent the fluorescence and phosphorescence spectral curves of the material, respectively. When the pyrene content is 1.0 mol %, the material exhibits fluorescence emission in the range of 350-550 nm and phosphorescence emission at 590 nm and 655 nm after being excited.

[0062] Fig.10Figure 1 is the fluorescence emission spectrum of porous room temperature phosphorescent materials with different pyrene contents; This figure is the organic room temperature phosphorescent material prepared in Example 6, where FL represents the phosphorescence spectrum. As shown in the figure, the wavelength range of the phosphorescence emission spectrum does not change with the change of pyrene content, but the fluorescence intensity changes from a lower wavelength to a higher wavelength. Fig.11 The figure is the phosphorescence emission spectra of porous room temperature phosphorescent materials with different pyrene contents; the figure is the organic room temperature phosphorescent material prepared in Example 6, where PL represents the phosphorescence spectrum, and the phosphorescence intensity gradually becomes stronger with the increase of pyrene content.

[0063] Fig.12 is the phosphorescence lifetime of porous room temperature phosphorescent materials with different pyrene contents at an emission wavelength of 590 nm; this figure is the phosphorescence lifetime spectrum of the organic room temperature phosphorescent materials prepared in Examples 5 and 6 at an excitation wavelength of 590 nm after being excited by ultraviolet rays of 365 nm.

[0064] Fig.13 is the phosphorescence lifetime of porous room temperature phosphorescent materials with different pyrene contents at an emission wavelength of 655 nm; this figure is the phosphorescence lifetime spectrum of the organic room temperature phosphorescent materials prepared in Examples 5 and 6 at an excitation wavelength of 655 nm after being excited by ultraviolet rays of 365 nm.

[0065] Fig.14 This is a SEM image of a porous room temperature phosphorescent material with a biphenyl, phenanthrene and pyrene content of 1%; this image is an organic room temperature phosphorescent material prepared in Examples 1, 3 and 5.

[0066] Fig.15 This is a BET diagram of a porous room temperature phosphorescent material with a biphenyl content of 1%; this diagram is the organic room temperature phosphorescent material prepared in Example 1.

[0067] Fig.16 This is an afterglow diagram of a porous room temperature phosphorescent material with a biphenyl, phenanthrene and pyrene content of 1%; this diagram is an organic room temperature phosphorescent material prepared in Examples 1, 3 and 5.

[0068] In summary, the present invention discloses a method for preparing a porous and ultra-long-life organic room temperature phosphorescent material by loading traditional polycyclic and condensed aromatic hydrocarbon phosphorescent molecules, such as biphenyl, naphthalene, anthracene, phenanthrene and pyrene, through in-situ self-assembly technology inside a hydrogel, and relates to the technical field of polymer functional materials. The raw materials include carboxyl monomers, amide bond monomers, crosslinking agents, initiators, phosphorescent molecules, organic solvents and deionized water; wherein the carboxyl monomers include methacrylic acid and acrylic acid, the amide bond monomers include N-vinyl caprolactam, N-isopropylacrylamide, methacrylamide, and polycyclic and condensed aromatic hydrocarbon phosphorescent molecules include biphenyl, naphthalene, anthracene, phenanthrene and pyrene. The present invention completes the preparation of an organic gel in dimethyl sulfoxide (DMSO), then constructs hydrogen bonds through solvent exchange to induce in-situ self-assembly, completes the loading of non-water-soluble polycyclic and condensed fluorescent substances, removes the moisture of the resulting hydrogel (natural volatilization or freeze drying), and finally realizes the preparation of a class of porous organic room temperature phosphorescent materials.

[0069] The present invention describes preferred embodiments and their effects. However, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0070] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for preparing porous organic ultra-long-lifetime room temperature phosphorescent materials by hydrogen bond induced self-assembly, characterized in that: The following steps are involved: Adding monomers, crosslinking agents, phosphorescent molecules, and initiators into an organic solvent and mixing them evenly to obtain a precursor solution; The precursor solution is injected into the mold and reacted at 60-70°C for 6-12 h to obtain an organogel; The organic gel is placed in deionized water for dialysis for 5 to 8 days, and the reorganization of hydrogen bonds inside the hydrogel is completed through the solvent exchange process to induce the in-situ self-assembly of polymer segments, and then the water is removed by natural drying or freeze drying to obtain a porous organic ultra-long-lifetime room temperature phosphorescent material; The monomers include carboxyl monomers and amide bond monomers.

2. The method for preparing porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly according to claim 1, characterized in that: The carboxyl monomer includes methacrylic acid and / or acrylic acid; the amide bond monomer includes one or more of N-vinyl caprolactam, N-isopropylacrylamide, and methacrylamide.

3. The method for preparing porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly according to claim 1, characterized in that: The phosphorescent molecules are one or more of biphenyl, naphthalene, anthracene, phenanthrene and pyrene.

4. The method for preparing porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly according to claim 1, characterized in that: The cross-linking agent is N,N'-methylenebisacrylamide; the initiator is azobisisobutyronitrile, potassium persulfate or ammonium persulfate; and the organic solvent is dimethyl sulfoxide.

5. The method for preparing porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly according to claim 1, characterized in that: The molar ratio of the carboxyl monomer to the amide bond monomer is (60-90): (40-10).

6. The method for preparing porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly according to claim 1, characterized in that: The amount of the crosslinking agent used is 1-5.0% of the molar amount of the monomer; the amount of the initiator added is 1-3% of the total mass of the monomer and the crosslinking agent; the amount of the organic solvent added is the volume number when the total molar concentration of the monomer and the crosslinking agent is 3-5 mol / L.

7. The method for preparing porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly according to claim 1, characterized in that: The mold includes two stacked glass plates and a silicone sheet sandwiched between the two glass plates, wherein a through hole is provided in the middle of the silicone sheet; the through hole and the glass plates at both ends form a closed cavity for injecting a precursor solution; wherein the thickness of the silicone sheet is 0.5-2 mm.

8. The method for preparing porous organic ultra-long-lifetime room temperature phosphorescent material by hydrogen bond induced self-assembly according to claim 1, characterized in that: The dialysis process is continued until the quality of the hydrogel no longer changes.

9. A porous organic ultra-long-lifetime room temperature phosphorescent material prepared by hydrogen bond induced self-assembly according to the method of any one of claims 1 to 8.

10. An application of the porous organic ultra-long-lifetime room temperature phosphorescent material created by hydrogen bond induced self-assembly as claimed in claim 9 in biological imaging, sensors, information encryption or organic light-emitting display materials.

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