Water-resistant room-temperature phosphorescent material with long service life and high quantum yield and application thereof

Abstract

The invention discloses a water-resistant room-temperature phosphorescent material with long service life and high quantum yield and application thereof, and the material is obtained by doping a binaphthol-containing functionalized phosphor monomer into a polymer matrix polyvinyl alcohol and then carrying out iodine dyeing-stretching-crosslinking (ISB). Through the heavy atom effect of iodine, the crossing of phosphorescence systems is enhanced, and the molecular structure rigidity is enhanced through boric acid crosslinking, so that long-life room-temperature phosphorescence emission from nothing to existence and from weak to strong is realized; the phosphorescence lifetime is increased by 28.4 times, and the phosphorescence quantum yield is increased by 24.1 times. The preparation method is simple to operate and low in production cost, has good universality, provides a new strategy for designing a long-life room-temperature phosphorescent material, and has good application prospects in the fields of antibiosis, water resistance, multicolor display, information encryption and the like.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of polymer long afterglow luminescent material, in particular to a long-life high quantum yield room temperature phosphorescence material and application thereof. BACKGROUND

[0002] Organic room temperature phosphorescence (RTP) materials have long phosphorescence lifetime and large Stokes shift, and have attracted extensive attention in the fields of information storage, biological imaging and optical sensors. Although organic RTP materials are favored in practical applications due to their structural modifiability and low cost, they generally have weak spin-orbit coupling and rapid non-radiative decay, which limits their application potential.

[0003] Introducing heavy atom effect is an effective strategy to improve RTP efficiency. For example, introducing halogen elements into phosphors or embedding them in polymer matrix can help promote the intersystem crossing process of triplet excitons, thereby improving the RTP emission efficiency. However, this method usually sacrifices phosphorescence lifetime because the intersystem crossing rate and phosphorescence emission rate will increase at the same time. Therefore, how to realize efficient phosphorescence emission by regulating heavy atom effect under the premise of long phosphorescence lifetime is still a great challenge. By constructing covalent cross-linked network, a large number of materials with high phosphorescence quantum yield (Φ P ) or long phosphorescence lifetime (τ P ) have been developed so far, but materials that can simultaneously possess both characteristics are still rare. This scarcity is mainly due to the mutual competition between phosphor radiative decay and non-radiative decay processes.

[0004] Currently, the strategy to realize high phosphorescence quantum yield and long phosphorescence lifetime in the same RTP material mainly relies on precise regulation of triplet excitons and multiple synergistic effects, but there are generally problems such as complex design and difficult preparation. SUMMARY

[0005] In view of the above problems in the prior art, the present application aims to provide a water-resistant long-life high quantum yield room temperature phosphorescence material, which solves the problems of the prior art that the high phosphorescence quantum yield Φ P and long phosphorescence lifetime τ P cannot be considered together, and the stability is poor, and the preparation is complex and the cost is high.

[0006] The present application also provides application of the water-resistant long-life high quantum yield room temperature phosphorescence material in underwater room temperature phosphorescence materials, antibacterial, information encryption.

[0007] In order to solve the above technical problems, the technical scheme adopted by the present application is as follows:

[0008] A water-resistant long-life high-quantum-yield room-temperature phosphorescent material is characterized in that it is prepared by the following method: a binaphthol functionalized phosphor monomer is doped into a polyvinyl alcohol polymer matrix, and then obtained by iodine dyeing-stretching-crosslinking (ISB); that is:

[0009] First, the binaphthol is functionalized, and then the functionalized phosphor is doped into a PVA matrix to form a polymer film; then the film is immersed in iodine water, stretched and oriented by a stretching machine, and crosslinked in a boric acid solution to obtain a long-life room-temperature phosphorescent material.

[0010] Further, the preparation method comprises the following steps:

[0011] S1, dissolving PVA in dimethyl sulfoxide at a concentration of 30-60 mg / mL to form a PVA@DMSO solution;

[0012] S2, mixing the binaphthol functionalized phosphor with the PVA@DMSO solution at a ratio of (0.1-2) mg:1 mL, and ultrasonicating for 30 min to obtain a uniform mixed solution;

[0013] S3, dropping the obtained mixed solution into a teflon mold, and drying to form a transparent film;

[0014] S4, obtaining the phosphorescent material by iodine dyeing, stretching, and boric dyeing;

[0015] That is, the cooled film is cut into small pieces, and immersed in deionized water at 35°C for at least 30 min to make the film reach a swelling equilibrium state; then the long-life high-quantum-yield room-temperature phosphorescent film reaching the swelling equilibrium state is immersed in 100 mL of iodine water solution (I:0.5 g; KI:0.25 g) for a few seconds;

[0016] The film is stretched by a stretching device to achieve several times deformation and keep for 2 min; after stretching, the BINs film is immersed in anhydrous ethanol for 5 min for setting treatment;

[0017] Then the film is immersed in a 4wt% boric acid solution for a few minutes to complete the crosslinking reaction; after the crosslinking reaction is completed, the film is washed with deionized water to remove the residual boric acid on the surface of the film, and dried in a 60°C oven overnight.

[0018] Further, the phosphorescent monomer precursor is any one of 1,1'-binaphthyl-2-naphthol (BINOL), 4-nitro phthalonitrile, tetrafluoro terephthalonitrile, carbazole, and 1-pyrene carboxylic acid; the precursor includes the structural formula (1) of BINOL:

[0019]

[0020] Further, the functionalized phosphor is synthesized based on BINOL precursor, having any of the structural formulae as shown in Figure (2):

[0021]

[0022] Further, the synthesis route of the functionalized phosphor DPBN, DFBN, DCBN and DPCA is shown in formula (3):

[0023]

[0024] The synthesis method of the functionalized phosphor DPBN, DFBN, DCBN and DPCA comprises the following steps:

[0025] Synthesis of DPBN: 2.9 g of BINOL, 3.8 g of 4-nitrophthalonitrile and 4.1 g of potassium carbonate were added to 30 mL of super dry N,N-dimethylformamide in a 50 mL three-necked flask under nitrogen atmosphere, and reacted at room temperature for 20 hours; then, the reaction mixture was slowly poured into a dilute hydrochloric acid solution (2N, 500 mL), and the generated solid was collected by filtration and washed with a large amount of deionized water until the filtrate was neutral; the obtained solid was recrystallized twice in a methanol / acetonitrile (1:1) solvent to obtain white powder DPBN;

[0026] Synthesis of DFBN: 1 g of tetrafluoro-p-terephthalonitrile and 1.4 g of BINOL were dissolved in 30 mL of super dry N,N-dimethylformamide in a 50 mL flask. Then, 1.4 g of potassium carbonate was added; under nitrogen protection, the reaction was carried out at room temperature for 12 hours; after the reaction was completed, the reaction mixture was poured into water, and the aqueous phase was extracted with ethyl acetate (3 times); after the organic phases were combined, they were washed with water and dried in an oven overnight, and finally light yellow powder DFBN was obtained;

[0027] Synthesis of DCBN: 30 mL of super dry N,N-dimethylformamide was added to a 50 mL three-necked flask, followed by the sequential addition of 1 g of DFBN, 0.8 g of carbazole and 1.5 g of potassium carbonate; under nitrogen protection, the reaction was stirred at room temperature for 2.5 hours; after the reaction was completed, 20 mL of water and 50 mL of dichloromethane were added to the reaction mixture; after the organic phase was washed with dichloromethane, it was dried with anhydrous magnesium sulfate, and then purified by column chromatography (n-hexane: ethyl acetate = 8:1), and finally yellow solid DCBN was obtained;

[0028] Synthesis of DPCA: 1 g of BINOL, 1.9 g of 1-pyrenecarboxylic acid, 2.2 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 1.2 g of 4-dimethylaminopyridine were dissolved in 20 mL of super dry N,N-dimethylformamide, and the reaction was stirred at 40°C for 22 hours; after the reaction was completed, water was added to quench the reaction, and extraction was performed twice with chloroform; after the organic phases were combined, washing was performed three times with water and saturated brine, drying was performed with anhydrous Mg2SO4, and after concentration, purification was performed by column chromatography (n-hexane: dichloromethane = 6:1), and finally, a yellow powder of DPCA was obtained.

[0029] The application also provides an application of the long-life high-quantum-yield room-temperature phosphorescent material, and the phosphorescent material is used for solvent-resistant, antibacterial, information encryption and flexible display room-temperature phosphorescent materials. The solvent-resistant is water, a hydrochloric acid solution with a pH of 1, a sodium hydroxide solution with a pH of 14, an organic mixed solvent with a volume ratio of dichloromethane:N,N dimethylformamide:dialkyl sulf oxide:ethyl acetate = 1:1:1:1, and hot water at 90°C.

[0030] Further, the application also provides an antibacterial application of the long-life high-quantum-yield room-temperature phosphorescent material, and the long-life high-quantum-yield room-temperature phosphorescent material is applied to bacteriostatic materials that can inhibit the growth of Escherichia coli and Staphylococcus aureus.

[0031] Compared with the prior art, the application has the following beneficial effects:

[0032] 1. The "heavy atom effect-stretching-crosslinking" (ISB) synergistic strategy provides a brand-new solution for designing water-resistant long-life high-quantum-yield RTP materials. After the ISB treatment of the phosphorescent material, the optimal phosphorescent lifetime is 1139.8 ms, the afterglow time can reach 11 s, and the optimal phosphorescent quantum yield is 33.8%. Compared with before the ISB treatment, the phosphorescent lifetime is increased by 28.4 times, and the phosphorescent quantum yield is increased by 24.1 times. Finally, through the heavy atom effect of iodine to enhance the intersystem crossing of the phosphorescent system and the crosslinking of boric acid to enhance the rigidity of the molecular structure, long-life room-temperature phosphorescent emission is achieved from nothing to something and from weak to strong. The preparation method is simple in operation, low in production cost and good in universality, and provides a new strategy for designing long-life room-temperature phosphorescent materials, and has good application prospects in the fields of antibacterial, water-resistant, multicolor display and information encryption. The long-life high-quantum-yield room-temperature phosphorescent material is synthesized simply, doped into a PVA matrix, and then subjected to ISB treatment, so that a large range of phosphorescent emission wavelength from 520 nm to 622 nm is realized.

[0033] 2, The water-resistant long-life high quantum yield room temperature phosphorescent material of the application can effectively promote spin-orbital coupling through the rich carbonyl groups on the PVA chain, is conducive to the intersystem crossing from singlet state to triplet state to generate a large number of triplet excitons, and enhances phosphorescent emission; the application innovatively introduces external heavy atom effect by using the complexation of iodine and PVA, effectively promotes the intersystem crossing from excited singlet state to excited triplet state; and further uses the crosslinking reaction of boric acid and PVA to inhibit the vibration deactivation of the phosphor. The order of magnitude of the phosphorescent lifetime and quantum yield is increased, which provides new strategies and theoretical support for the high-efficiency large-area industrial production of long-life high quantum yield phosphorescent materials.

[0034] 3, The pure organic phosphorescent material prepared by the application has the advantages of low cost and small biological toxicity. The application overcomes the defect of poor water resistance of PVA-based RTP materials; the DFBN thin film still maintains good luminescent performance even after being soaked in water for 5 days.

[0035] 4, Based on the existence of iodine element in the long-life high quantum yield phosphorescent material, the application expands the potential application prospect of polymer phosphorescent materials in antibacterial materials.

[0036] 5, The long-life room temperature phosphorescent thin film material has excellent luminescent performance, so the thin film can be cut and processed to prepare a desired pattern, and combined with the afterglow performance of the thin film, the application realizes the application in the fields of large-area flexible encryption and flexible display. BRIEF DESCRIPTION OF DRAWINGS

[0037] Figure 1 Nuclear magnetic resonance hydrogen spectrum (1d) of the phosphor prepared for examples 1-4 in deuterated dimethyl sulfoxide (1a-1c) and deuterated chloroform;

[0038] Figure 2 Phosphorescent real photo of the thin film of the water-resistant long-life high quantum yield room temperature phosphorescent material prepared for examples 1-4 under ultraviolet lamp excitation;

[0039] Figure 3 Phosphorescent spectrum of the water-resistant long-life high quantum yield room temperature phosphorescent material prepared for examples 1-4 under ultraviolet lamp excitation in an atmospheric room temperature environment;

[0040] Figure 4 Phosphorescent lifetime decay curve of the water-resistant long-life high quantum yield room temperature phosphorescent material prepared for examples 1-4 in an atmospheric room temperature environment;

[0041] Figure 5 Phosphorescent quantum yield change graph of the water-resistant long-life high quantum yield room temperature phosphorescent material prepared for examples 1-4 in an atmospheric room temperature environment;

[0042] Figure 6Test characterization of phosphorescence enhancement mechanism for phosphorescent materials prepared for Examples 1-4;

[0043] Figure 7 In-situ infrared spectrum for DFBN phosphorescent film;

[0044] Figure 8 Application diagram of water-resistant, antibacterial, encryption, display, etc. for water-resistant long-life high-quantum-yield room-temperature phosphorescent material of Examples 5-8. DETAILED DESCRIPTION

[0045] The specific embodiments of the present application will be further described in detail below with specific examples.

[0046] The numerical ranges in this disclosure are to be understood as specifically including every integer value within the range. In addition, any higher rank categorical scale, e.g., "at least one of A and B", is to be interpreted as the inclusion of all of the other subsets of A and B. Any use of a term in the singular in this specification or in claims is only intended to mean one or more, especially one. Any use of the term "comprising" is to be interpreted as "including". Any use of the term "including" is to be interpreted as "including without limitation". Any use of the term "consisting of" is to be interpreted as "consisting of, without limitation". Any use of the term "consisting essentially of" is to be interpreted as "consisting essentially of, without limitation". Any use of the term "substantially" is to be interpreted as "substantially, without limitation".

[0047] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present application, the preferred methods and materials are described. All documents mentioned in this specification are incorporated herein by reference to disclose and describe the methods and / or materials in connection with which the documents are cited. In case of conflict between the content of the specification and that of any document incorporated herein by reference, the content of the specification prevails. With respect to the words "comprise", "comprising", "include", "including", "contain", "containing", "have" and "having" or the like, these are to be construed in an open, non-limiting sense, i.e. in the sense of "including, but not limited to".

[0048] The experimental methods used in the present application are conventional methods unless otherwise specified.

[0049] The materials, reagents, etc. used in the present application can be purchased or synthesized by known methods unless otherwise specified.

[0050] In the quantitative test in the present application, three repeated experiments are set, and the average value is taken.

[0051] I. Examples 1-4:

[0052] Four phosphorescent materials: DPBN@PVA, DFBN@PVA, DCBN@PVA and DPCA@PVA were prepared. Among them, DPNB, DFBN, DCBN and DPCA are self-defined names.

[0053] A preparation method of a water-resistant long-life high-quantum-yield room-temperature phosphorescent material, comprising the following steps:

[0054] (1) Phosphor synthesized with BINOL (1,1'-binaphthalene) as precursor, whose structural formula is as follows:

[0055]

[0056] Referring to the attached Figure 1 wherein a, b, c and d can prove to be DPNB, DFBN, DCBN and DPCA respectively with the above structural formula.

[0057] Further, a preparation method of the above phosphor is provided, whose process route is as follows:

[0058]

[0059] Preparation of DPBN:

[0060] Under nitrogen atmosphere, 2.9g BINOL, 3.8g 4-nitrophthalonitrile and 4.1g potassium carbonate, 30mL super dry N,N-dimethylformamide are added into a 50mL three-necked flask, and reacted at room temperature for 20 hours. Subsequently, the reaction mixture is slowly poured into a dilute hydrochloric acid solution (2N, 500mL), and the generated solid is collected by filtration and washed with a large amount of deionized water until the filtrate is neutral. The obtained solid is recrystallized twice in a methanol / acetonitrile (1:1) solvent to obtain white powder DPBN.

[0061] Synthesis of DFBN: In a 50mL flask, 30mL super dry N,N-dimethylformamide is added to dissolve 1g tetrafluoro-p-terephthalonitrile and 1.4g BINOL. Subsequently, 1.4g potassium carbonate is added. Under nitrogen protection, the reaction is carried out at room temperature for 12 hours. After the reaction is completed, the reaction mixture is poured into water, and the aqueous phase is extracted with ethyl acetate (3 times). After the organic phases are combined, they are washed with water and dried in an oven overnight, and finally the light yellow powder DFBN is obtained.

[0062] Synthesis of DPCA: In a 50mL three-necked flask, 30mL super dry N,N-dimethylformamide is added, followed by the addition of 1g DFBN, 0.8g carbazole and 1.5g potassium carbonate in sequence. Under nitrogen protection, the reaction is stirred at room temperature for 2.5 hours. After the reaction is completed, 20mL water and 50mL dichloromethane are added to the reaction mixture. After the organic phase is washed with dichloromethane, it is dried using anhydrous magnesium sulfate, and then purified by column chromatography (n-hexane: ethyl acetate = 8:1), and finally the yellow solid DPCA is obtained.

[0063] Synthesis of DPCA: 1 g of BINOL, 1.9 g of 1-pyrenecarboxylic acid, 2.2 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, and 1.2 g of 4-dimethylaminopyridine were dissolved in 20 mL of super dry N,N-dimethylformamide, and the reaction was stirred at 40°C for 22 hours. After the reaction was completed, water was added to quench the reaction, and extraction was performed twice with chloroform. After the organic phases were combined, washing was performed three times with water and saturated brine, drying was performed with anhydrous MgSO4, and after concentration, purification was performed by column chromatography (n-hexane: dichloromethane = 6:1), and finally, a yellow powder of DPCA was obtained.

[0064] (2) Preparation of long-life high quantum yield room temperature phosphorescent thin film

[0065] S1, PVA (Polyvinyl Alcohol) with an alcoholysis degree of 100% was dissolved in DMSO (Dimethyl sulfoxide) at 100°C for 2 hours to obtain a PVA@DMSO solution (45 mg / mL), which was filtered and cooled;

[0066] S2, the above four phosphors were respectively added to the PVA@DMSO solution and ultrasonically treated for 30 min to obtain a uniform solution, and the obtained phosphor and PVA solution were mixed at (0.1-2) mg: 1 mL;

[0067] S3, the above uniform solution of step S2 was respectively injected into a polytetrafluoroethylene (PTFE) mold (100 mm x 80 mm x 5 mm), and after the thin film was naturally detached from the mold, it was taken out of the oven and cooled to room temperature; the mold was placed in a 85°C air oven to rapidly evaporate the solvent;

[0068] S4, the prepared phosphorescent material was treated by iodine staining, stretching, and boron staining;

[0069] The cooled thin film was cut into a small piece of thin film with a length and width of 50 mm x 40 mm, and was immersed in deionized water at 35°C for at least 30 min to make the thin film fully reach a swelling equilibrium state; the long-life high quantum yield room temperature phosphorescent thin film that reached the swelling equilibrium was immersed in 100 mL of an iodine aqueous solution (I: 0.5 g; KI: 0.25 g) for a few seconds.

[0070] The thin film was stretched using a stretching device to make it reach several times deformation and maintain for 2 min (marked as S y ). After stretching was completed, the BINs thin film was immersed in anhydrous ethanol for 5 min for setting treatment. The stretching device can be a simple stretching device with a model number of ZP-10 produced and sold by Shenzhen Ailigeng Instrument Co., Ltd., or other similar stretching devices.

[0071] Then the film is immersed in a 4wt% boric acid solution for several minutes to complete the cross-linking reaction. After the cross-linking reaction is completed, the film is washed with deionized water to remove the residual boric acid on the surface of the film.

[0072] The washed film is placed in a 60℃ oven and dried overnight.

[0073] II. Application research of water-resistant long-life high quantum yield room temperature phosphorescent material (film)

[0074] Herein only the DFBN room temperature phosphorescent material in the present application is taken as an example for illustration.

[0075] The DFBN room temperature phosphorescent material is soaked in a solvent for 0-120h, and the change of afterglow time and phosphorescent intensity under 365nm ultraviolet light excitation is compared to measure the solvent resistance of the material. Among them, the tested solvents are water (room temperature), 1 pH hydrochloric acid solution, 14 pH sodium hydroxide solution, organic mixed solvent with a volume ratio of dichloromethane: N,N dimethylformamide: dimethyl sulfoxide: ethyl acetate = 1:1:1:1, 90℃ hot water; the DFBN is placed in an escherichia coli / staphylococcus aureus culture medium, and the growth of the inhibition zone is observed to determine the antibacterial ability. The observation results are as follows: Figure 8 a, 8c can be seen that even after continuous immersion in water for 120h, the DFBN@PVA material still has long time and high intensity phosphorescent emission, Figure 8 b is the afterglow photo of the DFBN@PVA material after being immersed in strong acid, strong base, mixed organic solvent and hot water for 12h; combined with the above data, it shows that the ISB strategy effectively improves the solvent resistance and stability of the DFBN@PVA material. Figure 8 c, 8d is the inhibition zone experiment, and by comparing the growth of the inhibition zone, it can be known that the DFBN@PVA material treated by ISB has certain antibacterial performance. Figure 8 e is an information encryption means based on the different phosphorescent lifetimes of the four phosphorescent materials; specifically, the encrypted information exhibits different numbers as the phosphorescence of the material is quenched. Figure 8 f is a complex pattern prepared based on the phosphorescent performance of the DFBN@PVA material, which reflects its ornamental value.

[0076] III. Result monitoring analysis

[0077] (1) Structure and performance detection

[0078] For example, Figure 1As shown, the structures and purities of the four phosphors obtained were confirmed by H NMR spectroscopy. By integrating the peak areas of the H NMR spectrum, the ratio of the integrated areas is consistent with the ratio of the number of hydrogen atoms in the target phosphors, which confirms that the four phosphors have been successfully synthesized and purified. Among them, a, b and c are the H NMR spectra of the prepared phosphor materials in deuterated dimethyl sulfoxide, and d is the H NMR spectrum of the prepared phosphor material in deuterated chloroform.

[0079] (2) Photophysical properties test

[0080] The DPBN@PVA phosphorescent material is excited by a 254nm ultraviolet lamp; the DFBN@PVA, DCBN@PVA, and DPCA@PVA phosphorescent materials are excited by a 365nm ultraviolet lamp.

[0081] Figure 2 The following are photos of the four water-resistant, long-life, high-quantum-yield room-temperature phosphorescent materials exhibiting film phosphorescence under ultraviolet light excitation. Figure 2 As shown in the figure, under room temperature and atmospheric environment, all long-lifetime and high quantum yield phosphorescent films have obvious fluorescence emission under the irradiation of ultraviolet light. After removing the excitation source, they can emit phosphorescent emission visible to the naked eye for up to 12 seconds.

[0082] Figures 3-5 These are the phosphorescence spectra, phosphorescence lifetimes and phosphorescence quantum yields of four long-lifetime, high-quantum-yield phosphorescent films before and after ISB treatment; Pre-ISB refers to the component without ISB treatment, and Post-ISB refers to the component after ISB treatment.

[0083] Combine Figures 3-5 It can be seen that after ISB treatment, the phosphorescence intensity, phosphorescence lifetime, and phosphorescence quantum yield of all systems were significantly improved. The improvement was particularly significant for the DFBN@PVA phosphorescent material, which achieved long-lifetime, high-brightness RTP emission from scratch. This provides a new approach for the preparation of long-lifetime, high-quantum-yield room-temperature phosphorescent materials.

[0084] Figure 6 In order to test and characterize the phosphorescence enhancement mechanism of the phosphorescent materials prepared in Examples 1-4, the structural changes of the materials before and after ISB treatment were analyzed to illustrate how the ISB strategy enhances the RTP performance of the materials. Figure 6 a is the infrared spectrum; it can be seen that after ISB treatment, at 1325cm -1 There is an obvious BO vibration absorption peak at 660cm -1 The characteristic absorption peak of iodine was observed at 3300 cm, which indicates that iodine and boron were successfully introduced into the PVA matrix. -1) shifts to higher wavenumbers, which is attributed to the polyiodide ions (such as I3 - , I5 - ) and the oxygen atoms in the -OH groups in PVA, which weakens the hydrogen bonding between and within PVA molecules. Figure 6 Raman spectroscopy analysis in b shows that after ISB treatment, the iodine element in the amorphous region of PVA is mainly in the form of I3 - (106cm -1 ) and I5 - (160cm -1 However, Raman spectroscopy can only reflect the I3 - and I5 - The change of ion concentration cannot clearly distinguish whether the polyiodide ions exist in a free state or form a complex with the PVA molecular chain segment. To further verify this, solid-state UV-Vis testing was performed. Figure 6 As shown in Figure c, with the extension of iodine staining time, the absorption peaks of region 1 and region 2 gradually increase, indicating that PVA-I3 is gradually formed in the amorphous region of PVA. - and PVA-I5 - The PVA-I complex may exist as a cross-linking point in the PVA network. Stretching not only promotes the absorption of iodine by PVA, but also induces the transformation of the crystal structure of the DFBN material after ISB treatment. In the XRD spectrum, the change in the peak intensity at 2θ = 20° indicates that the crystallinity of PVA has increased ( Figure 6 d). At the same time, Figure 6 The enhancement of the two-dimensional wide-angle X-ray scattering (2D WAXS) diffraction rings in e further verifies this conclusion.

[0085] However, the weakening of the two-dimensional small-angle X-ray scattering (2D SAXS) diffraction rings indicates that the long-range order and crystal thickness of the DFBN material have decreased ( Figure 6 f), which may be due to the destruction of the crystal structure of PVA by the introduction of iodine. In addition, the SEM images of the DFBN film after ISB treatment showed that the DFBN film was significantly oriented perpendicular to the stretching direction, further confirming this structural transformation ( Figure 6 g)

[0086] further, Figure 7In situ infrared test data show that as the temperature increases, the hydroxyl peak in the DFBN phosphorescent film shifts to a certain extent. This is because high temperature destroys the intermolecular hydrogen bonds but does not destroy the PVA chain structure, as the intensity of the hydroxyl peak in the figure does not change significantly. In addition, the covalent cross-linked network endowed by the ISB system is not destroyed, as obvious BO vibration absorption peaks and iodine characteristic absorption peaks can still be observed. The excellent thermal stability not only provides a guarantee for the excellent RTP performance of the DFBN phosphorescent film, but also gives it the potential to maintain good performance in harsh environments.

[0087] 1. Application Examples 5-8 of Phosphorescent Films

[0088] Taking DFBN phosphorescent film as an example, its applications in water resistance, antibacterial, encryption, display, etc. are explained.

[0089] Application Example 1: Application of DFBN phosphorescent film in underwater room temperature phosphorescent materials

[0090] It is well known that water has a fatal quenching effect on room-temperature phosphorescent materials, especially those based on PVA as a polymer matrix. Therefore, improving the water resistance of PVA-based room-temperature phosphorescent materials is crucial for expanding their applications. By soaking the materials in iodine water to form a PVA-I complex, stretching and orienting them, and crosslinking them in a boric acid solution to form a dense crosslinked network, they effectively block water erosion.

[0091] The lower half of the DFBN phosphorescent film was immersed in a solution and the upper half was exposed to the atmosphere. Comparing the RTP performance of the upper and lower parts of the DFBN phosphorescent film, it was found that even after being immersed in water for 5 days, the phosphorescence intensity of the optimal phosphorescence emission peak of the DFBN phosphorescent film still remained above 25% of the initial intensity ( Figure 8 a, 8c), showing good RTP performance. In addition, after being soaked in strong acid, strong base, various organic mixed solvents and hot water for 12 hours, the DFBN@PVA film can still maintain a certain RTP performance ( Figure 8 b). It shows that the ISB strategy greatly improves the environmental tolerance of PVA-based RTP materials.

[0092] Application Example 2: Application of DFBN Film in Antibacterial Room-Temperature Phosphorescent Materials

[0093] The inhibition zone experiment shows that the DFBN phosphorescent film has a significant bactericidal effect on Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus), indicating that it has great application potential in antibacterial RTP materials ( Figure 8 d).

[0094] Application Example 3: Application of DFBN Film in Information Encryption and Flexible Display

[0095] Then, based on the afterglow characteristics of DFBN phosphor film and DPCA phosphor film, a dynamic encryption concept map is designed. The encryption information changes with time and reaches stability after 7s Figure 8 e) Finally, a series of patterns are designed using DFBN phosphor film to show its potential in flexible display Figure 8 f).

[0096] Similarly, the water-resistant long-life high quantum yield room temperature phosphorescent material (film) based on DPBN, DCBN and DPCA prepared by the present application has good stability, and has high phosphorescent quantum yield and long phosphorescent lifetime, and is especially suitable for underwater RTP materials, antibacterial and information encryption applications. At the same time, the preparation method of the long-life high quantum yield RTP material described in the present application solves the problems of complex preparation and high cost of existing polymer long afterglow luminescent materials.

[0097] In summary, the present application proposes a "heavy atom effect-stretching-crosslinking" (ISB) synergistic strategy, which provides a new solution for designing long-life high quantum yield RTP materials. The DFBN phosphor film treated by ISB exhibits RTP emission with double advantages of long lifetime and high quantum yield, with a phosphorescent lifetime of 1239.8 ms, which is 28.4 times longer than before treatment, and a phosphorescent quantum yield of 33.8%, which is 24.1 times higher. Through structural characterization, it is found that the ISB strategy provides a complete covalent crosslinking network and strong SOC effect for long-life high-efficiency RTP emission of room temperature phosphorescent materials. In addition, the DFBN phosphor film treated by ISB has strong environmental tolerance, so that it can still maintain bright RTP emission even after being immersed in water for five days, significantly improving the poor environmental tolerance of PVA-based RTP materials. This strategy provides a new idea for the development of multi-color information encryption, underwater RTP display and antibacterial materials.

[0098] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application and not to limit the technical solutions. Those of ordinary skill in the art should understand that modifications or equivalent replacements to the technical solutions of the present application without departing from the spirit and scope of the technical solutions should be covered in the scope of the claims of the present application.

Claims

1. A water-resistant, long-life, high-quantum-yield room-temperature phosphorescent material, characterized in that: The method is as follows: a functionalized phosphor monomer containing binaphthol is doped into a polymer matrix polyvinyl alcohol, and then iodine dyeing-stretching-crosslinking (ISB) is performed to obtain the phosphor; namely: First, binaphthol is functionalized, and then the functionalized phosphor is incorporated into a PVA matrix to prepare a polymer film; subsequently, the film is immersed in iodine water, stretched and oriented using a stretching device, and cross-linked in a 4wt% boric acid solution to prepare a long-life room-temperature phosphorescent material.

2. The water-resistant, long-life, high-quantum-yield room-temperature phosphorescent material according to claim 1, characterized in that: The following steps are involved: S1, dissolving PVA in dimethyl sulfoxide at a concentration of 30-60 mg / mL to form a PVA@DMSO solution; S2. Mix the binaphthol-functionalized phosphor with PVA@DMSO solution at a ratio of (0.1-2) mg:1 mL and sonicate for 30 min to obtain a uniform mixed solution; S3, dripping the obtained mixed solution into a tetrafluoroethylene mold and drying it to form a transparent film; S4, preparing the phosphorescent material by iodine dyeing, stretching, and boron dyeing; The cooled film was cut into small pieces and immersed in deionized water at 35° C. for at least 30 minutes to allow the film to fully reach a swelling equilibrium state. The long-life, high-quantum-yield, room-temperature phosphorescent film that reached swelling equilibrium was then immersed in 100 mL of an iodine aqueous solution (I: 0.5 g; KI: 0.25 g) for several seconds. The film was stretched using a stretching device to achieve several times deformation and maintained for 2 minutes. After the stretching was completed, the BINs film was immersed in anhydrous ethanol for 5 minutes to perform shaping treatment. The film was then immersed in a 4 wt % boric acid solution for several minutes to complete the cross-linking reaction. After the cross-linking reaction was completed, the film was washed with deionized water to remove the boric acid remaining on the surface of the film and dried in a 60° C. oven overnight.

3. The water-resistant, long-life, high-quantum-yield room-temperature phosphorescent material according to claim 1, characterized in that: The phosphorescent monomer precursor is any one of 1,1'-bi-2-naphthol (BINOL), 4-nitrophthalonitrile, tetrafluoroterephthalonitrile, carbazole and 1-pyrenecarboxylic acid; the precursor includes the structural formula (1) of BINOL:

4. The water-resistant, long-life, high-quantum-yield room-temperature phosphorescent material according to claim 3, characterized in that: The functionalized phosphor is synthesized based on the precursor BINOL and has any of the structural formulas shown in Figure (2):

5. The water-resistant, long-life, high-quantum-yield room-temperature phosphorescent material according to claim 4, characterized in that: The synthesis routes of the functionalized phosphors DPBN, DFBN, DCBN and DPCA are shown in formula (3): The method for synthesizing the functionalized phosphors DPBN, DFBN, DCBN and DPCA comprises the following steps: Synthesis of DPBN: Under a nitrogen atmosphere, 2.9 g of BINOL, 3.8 g of 4-nitrophthalonitrile, 4.1 g of potassium carbonate, and 30 mL of ultra-dry N,N-dimethylformamide were added to a 50 mL three-necked flask and reacted at room temperature for 20 hours. Subsequently, the reaction mixture was slowly poured into a dilute hydrochloric acid solution (2N, 500 mL). The resulting solid was collected by filtration and washed with copious amounts of deionized water until the filtrate was neutral. The resulting solid was recrystallized twice from a methanol / acetonitrile (1:1) solvent to obtain DPBN as a white powder. Synthesis of DFBN: In a 50 mL flask, dissolve 1 g of tetrafluoroterephthalonitrile and 1.4 g of BINOL in 30 mL of ultra-dry N,N-dimethylformamide. Subsequently, add 1.4 g of potassium carbonate. Incubate at room temperature under nitrogen for 12 hours. After completion of the reaction, pour the reaction mixture into water and extract the aqueous phase with ethyl acetate (three times). Combine the organic phases, wash with water, and dry in an oven overnight to obtain DFBN as a light yellow powder. Synthesis of DCBN: In a 50 mL three-necked flask, add 30 mL of ultra-dry N,N-dimethylformamide, followed by 1 g of DFBN, 0.8 g of carbazole, and 1.5 g of potassium carbonate. Stir the reaction at room temperature under nitrogen for 2.5 hours. After the reaction, add 20 mL of water and 50 mL of dichloromethane to the reaction mixture. Wash the organic phase with dichloromethane, dry it over anhydrous magnesium sulfate, and purify it by column chromatography (n-hexane:ethyl acetate = 8:1) to obtain DCBN as a yellow solid. Synthesis of DPCA: Dissolve 1 g of BINOL, 1.9 g of 1-pyrenecarboxylic acid, 2.2 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride, and 1.2 g of 4-dimethylaminopyridine in 20 mL of ultra-dry N,N-dimethylformamide and stir at 40°C for 22 hours. After completion of the reaction, quench the reaction with water and extract twice with chloroform. The combined organic phases are washed three times with water and saturated brine, dried over anhydrous MgSO, concentrated, and purified by column chromatography (hexane:dichloromethane = 6:1) to obtain DPCA as a yellow powder.

6. A water-resistant, long-life, high-quantum-yield room-temperature phosphorescent material, characterized in that: The phosphorescent materials DPBN@PVA, DFBN@PVA, DCBN@PVA and DPCA@PVA are prepared by the method according to any one of claims 1 to 5.

7. Application of a water-resistant, long-life, high-quantum-yield room-temperature phosphorescent material, characterized in that: The phosphorescent material according to claim 6 is used as a room temperature phosphorescent material for solvent resistance, antibacterial, information encryption, and flexible display.

8. The use of the water-resistant, long-life, high-quantum-yield room-temperature phosphorescent material according to claim 7, characterized in that: The tolerated solvents are water, hydrochloric acid solution with a pH of 1, sodium hydroxide solution with a pH of 14, an organic mixed solvent with a volume ratio of dichloromethane:N,N-dimethylformamide:dimethyl sulfoxide:ethyl acetate = 1:1:1:1, and hot water at 90°C.

9. An antibacterial application of a water-resistant, long-life, high-quantum-yield room-temperature phosphorescent material, characterized in that: The water-resistant, long-life, high-quantum-yield room-temperature phosphorescent material according to claim 6 is used as an antibacterial material capable of inhibiting the growth of Escherichia coli / Staphylococcus aureus.

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