An organic long-afterglow material, a preparation method and application thereof

Abstract

This invention relates to the field of organic materials technology, and discloses an organic long afterglow material, its preparation method, and its application. The application of the compound shown in formula (I) in organic long afterglow materials; formula (I); wherein R is selected from deuterium, H, Cl-C 20 Alkyl or C3-C 20 Cycloalkyl compounds. Compounds of formula (I) are used as guest molecules in organic long-afterglow materials. They have no afterglow properties themselves. When substances including melamine-formaldehyde resin are used as the main components of organic long-afterglow materials, the resulting organic long-afterglow materials have stable long-afterglow performance after guest doping. Organic long-afterglow materials can effectively resist the phosphorescence quenching behavior of guest molecules by oxygen. Under aerobic conditions, the afterglow color changes after illumination, shifting from orange-red to red or dark red, and the color change has good reversibility. Under anaerobic conditions, the afterglow color does not change before and after illumination, so it can be used for oxygen detection.

Description

Technical Field

[0001] This invention relates to the field of organic materials technology, and in particular to an organic long afterglow material, its preparation method, and its application. Background Technology

[0002] Long-persistent materials continue to emit light after the excitation source ceases, effectively eliminating the influence of short-lived background light and significantly improving the clarity and recognizability of the emitted signal. Therefore, these materials are widely used in fields such as bioimaging, chemical sensing, information encryption, and display devices. Traditionally, long-persistent materials are mainly composed of inorganic components. While inorganic long-persistent materials offer excellent performance, they suffer from drawbacks such as high production costs and material toxicity. In contrast, organic room-temperature phosphorescent materials, with their flexible structural design, ease of processing and modification, good biocompatibility, and dynamically tunable color, are gradually replacing traditional long-persistent materials.

[0003] Stimulus-responsive smart long-afterglow materials have received widespread attention in recent years. Among them, photoresponsive materials have a wide range of applications due to their unique properties and ability to achieve light-induced afterglow color changes. Specifically, it is reflected in the following aspects: (1) Photochromic materials can achieve multi-dimensional control of color, time, and space, which makes them potentially valuable in fields such as advanced data encryption and multi-color photonic barcode design; (2) They can be designed for multi-color photonic barcodes for advanced data encryption, as well as information storage media with three-dimensional ultra-high information storage capacity, showing good application prospects in the fields of information storage and encryption; (3) They can be used to realize optical waveguides, thus playing a role in optical communication technology; (4) They can be added to clothing or building coatings to enhance aesthetics and bring fun to life, or used in eyeglass lenses to intelligently adjust photosensitivity and protect the eyes from strong light damage; (5) They have ultra-long luminescence lifetime and have potential application value in fields such as light-emitting displays and sensors; (6) They have good reversibility and cycle stability, and have a long service life and reliability in practical applications; (7) They can be used as smart materials to respond to external light stimulation and realize intelligent and controllable changes in optical performance; (8) They have time-dependent color-changing phosphorescence, providing new tools and opportunities for multi-level encryption and dynamic storage of information.

[0004] In environments requiring strict control of gas composition, such as anaerobic experiments, the presence of oxygen can alter reaction pathways and rates. Therefore, visual monitoring of oxygen and the qualification testing of anaerobic apparatus are crucial. The photo-induced afterglow color change characteristics of photoresponsive materials offer one approach to achieving visual oxygen monitoring; however, current phosphorescent materials are easily quenched by oxygen, significantly impacting the accuracy of detection results. Summary of the Invention

[0005] The present invention aims to at least solve one of the aforementioned technical problems existing in the prior art. Therefore, one objective of the present invention is to provide the application of the compound of formula (I) in organic long afterglow materials; a second objective of the present invention is to provide an organic long afterglow material; a third objective of the present invention is to provide a method for preparing such an organic long afterglow material; a fourth objective of the present invention is to provide a polymer film; and a fifth objective of the present invention is to provide the application of the organic long afterglow material, or the polymer film.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A first aspect of the present invention provides the use of the compound of formula (I) in organic long afterglow materials;

[0008] Equation (Ⅰ);

[0009] R is selected from deuterium, H, and Cl-C. 20 Alkyl or C3-C 20 Cycloalkyl.

[0010] In some embodiments of the present invention, the compound represented by formula (I) is selected from at least one of the following compounds:

[0011] , .

[0012] A second aspect of the present invention provides an organic long afterglow material comprising a host component and a guest molecule doped in the host component; the guest molecule comprising a compound of formula (I) as described in the first aspect of the present invention.

[0013] In some embodiments of the present invention, the mass fraction of the guest molecule in the organic long afterglow material is 0.001%-5%.

[0014] In some embodiments of the present invention, the main component includes melamine-formaldehyde resin.

[0015] In this invention, melamine-formaldehyde resin is used as the main component of the organic long afterglow material. Its cross-linking structure can effectively prevent the phosphorescence quenching behavior of guest molecules by oxygen, so that the organic long afterglow material has stable long afterglow performance in the presence of oxygen.

[0016] In some embodiments of the present invention, the organic long afterglow material comprises the following raw materials: guest molecule solution and melamine-formaldehyde resin prepolymer solution.

[0017] In some embodiments of the present invention, the guest molecule solution comprises a guest molecule and an organic solvent.

[0018] In some embodiments of the present invention, the organic solvent is selected from one of tetrahydrofuran, methanol, ethanol, acetone, dimethyl sulfoxide, N,N-dimethylformamide, and acetonitrile.

[0019] In some specific embodiments of the present invention, the organic solvent is tetrahydrofuran.

[0020] In some embodiments of the present invention, the concentration of the guest molecule in the guest molecule solution is 1-4 mg / mL.

[0021] In some specific embodiments of the present invention, the concentration of the guest molecule in the guest molecule solution is 1-2 mg / mL.

[0022] In some embodiments of the present invention, the melamine-formaldehyde resin prepolymer solution is prepared by heating and reacting an aqueous solution of melamine and formaldehyde.

[0023] In some embodiments of the present invention, the concentration of the formaldehyde aqueous solution is 30-40 wt%.

[0024] In some specific embodiments of the present invention, the concentration of the formaldehyde aqueous solution is 35-40 wt%.

[0025] In some embodiments of the present invention, the solid-liquid ratio of the melamine to the formaldehyde aqueous solution is (110-130) mg: 1 mL.

[0026] In some specific embodiments of the present invention, the solid-liquid ratio of the melamine to the formaldehyde aqueous solution is (115-125) mg: 1 mL.

[0027] In some embodiments of the present invention, the melamine-formaldehyde resin prepolymer solution is prepared by heating at a temperature of 80-110°C.

[0028] In some specific embodiments of the present invention, the heating temperature for preparing the melamine-formaldehyde resin prepolymer solution is 90-100°C.

[0029] In some embodiments of the present invention, the reaction time for preparing the melamine-formaldehyde resin prepolymer solution is 1-4 hours.

[0030] In some specific embodiments of the present invention, the reaction time for preparing the melamine-formaldehyde resin prepolymer solution is 1-3 hours.

[0031] In some embodiments of the present invention, the pH value of the melamine-formaldehyde resin prepolymer solution is 8-10.

[0032] In some specific embodiments of the present invention, the pH value of the melamine-formaldehyde resin prepolymer solution is 8-9.

[0033] In some embodiments of the present invention, the pH value of the melamine-formaldehyde resin prepolymer solution is adjusted by adding at least one of an amine, an alkali metal hydroxide, and an alkali metal carbonate.

[0034] In some specific embodiments of the present invention, the pH value of the melamine-formaldehyde resin prepolymer solution is adjusted by adding at least one of diethylamine, triethylamine, triethanolamine, sodium hydroxide, potassium hydroxide, and sodium carbonate.

[0035] A third aspect of the present invention provides a method for preparing the organic long afterglow material described in the second aspect of the present invention, comprising the following steps:

[0036] The guest molecule solution is mixed with a melamine-formaldehyde resin prepolymer solution and heated to react, thereby obtaining the organic long afterglow material.

[0037] In some embodiments of the present invention, the heating reaction includes a first-stage heating reaction and a second-stage heating reaction.

[0038] In some embodiments of the present invention, the temperature of the heating reaction is 75-95°C and the time is 1-3 hours.

[0039] In some specific embodiments of the present invention, the temperature of the heating reaction is 80-90°C and the time is 1-2 hours.

[0040] In some embodiments of the present invention, the temperature of the two-stage heating reaction is 120-140°C and the time is 0.5-2 hours.

[0041] In some specific embodiments of the present invention, the temperature of the two-stage heating reaction is 125-135°C and the time is 1-1.5h.

[0042] A fourth aspect of the present invention provides a polymer film, wherein the raw materials for preparing the polymer film include the organic long afterglow material described in the second aspect of the present invention.

[0043] In some embodiments of the present invention, the polymer film comprises a material prepared by hot pressing of the organic long afterglow material.

[0044] In some embodiments of the present invention, the temperature of the hot pressing process is 140-160°C.

[0045] In some specific embodiments of the present invention, the temperature of the hot pressing process is 145-165°C.

[0046] In some embodiments of the present invention, the pressure of the hot pressing process is 15-20 MPa.

[0047] In some specific embodiments of the present invention, the pressure of the hot pressing process is 15-18 MPa.

[0048] In some embodiments of the present invention, the hot pressing process takes 5-15 minutes.

[0049] In some specific embodiments of the present invention, the hot pressing process takes 8-12 minutes.

[0050] The fifth aspect of the present invention provides the application of the organic long afterglow material described in the second aspect of the present invention, or the polymer film described in the fourth aspect of the present invention, in oxygen detection.

[0051] In some embodiments of the present invention, the application includes the qualification testing of oxygen-free devices.

[0052] In some embodiments of the invention, the application includes irradiating the organic long afterglow material and / or the polymer film with light.

[0053] In this invention, the organic long afterglow material and polymer film, under aerobic conditions, change the afterglow color from orange-red to red or dark red after being exposed to light. Under oxygen-free conditions, there is no light-induced afterglow color change, so they can be used for oxygen detection.

[0054] Compared with the prior art, the beneficial effects of the present invention are:

[0055] The compound of formula (I) provided by the present invention can be used as a guest molecule in organic long afterglow materials. The compound of formula (I) itself has no afterglow properties. With substances including melamine-formaldehyde resin as the main components of organic long afterglow materials, after guest doping, the resulting organic long afterglow materials have stable long afterglow performance.

[0056] The organic long afterglow material provided by this invention can effectively resist the phosphorescence quenching behavior of guest molecules by oxygen. Under aerobic conditions, the afterglow color changes after illumination, shifting from orange-red to red or dark red, and the color change is reversible. Under anaerobic conditions, the afterglow color does not change before and after illumination, so it can be used for oxygen detection. Attached Figure Description

[0057] Figure 1 The 1H NMR spectrum of compound (1) in Example 1;

[0058] Figure 2 The 1H NMR spectrum of compound (2) in Example 2;

[0059] Figure 3 The steady-state emission spectra of the solid powders of compounds (1) and (2) in the embodiments are shown below;

[0060] Figure 4 The following are luminescence decay curves of the solid powders of compounds (1) and (2) in the embodiments;

[0061] Figure 5 The steady-state emission spectra of the organic long afterglow materials in Examples 1 and 2 are shown.

[0062] Figure 6 The images show the afterglow emission spectra of the organic long afterglow materials in Examples 1 and 2.

[0063] Figure 7 The graphs show the afterglow decay curves of the organic long afterglow materials in Examples 1 and 2.

[0064] Figure 8 The UV absorption curve of the organic long afterglow material in Example 1 as the illumination time increases;

[0065] Figure 9 The UV absorption curve of the organic long afterglow material in Example 2 as the illumination time increases;

[0066] Figure 10 The steady-state emission spectrum and afterglow emission spectrum of the organic long afterglow material before ultraviolet irradiation in Example 1 are shown.

[0067] Figure 11 The steady-state emission spectrum and afterglow emission spectrum of the organic long afterglow material after ultraviolet irradiation in Example 1 are shown.

[0068] Figure 12 The steady-state emission spectrum and afterglow emission spectrum of the organic long afterglow material before ultraviolet irradiation in Example 2 are shown.

[0069] Figure 13 The steady-state emission spectrum and afterglow emission spectrum of the organic long afterglow material after ultraviolet irradiation in Example 2 are shown.

[0070] Figure 14 This is a comparison of the afterglow emission spectra of the organic long afterglow material in Example 1 before and after illumination under oxygen-free conditions;

[0071] Figure 15 This is a comparison of the afterglow emission spectra of the organic long afterglow material before and after illumination under oxygen-free conditions in Example 2;

[0072] Figure 16 This is a comparison of the afterglow luminescence decay curves of the organic long afterglow material before and after illumination in Example 1;

[0073] Figure 17This is a comparison of the afterglow luminescence decay curves of the organic long afterglow material before and after illumination in Example 2;

[0074] Figure 18 This is a diagram showing the afterglow color change stability of the organic long afterglow material in Example 1;

[0075] Figure 19 This is a diagram showing the afterglow color change stability of the organic long afterglow material in Example 2;

[0076] Figure 20 The CIE chromaticity diagram of the organic long-afterglow material in Example 1 during 0-5 min of illumination;

[0077] Figure 21 The image shows the CIE chromaticity diagram of the organic long-afterglow material in Example 2 during 0-5 minutes of illumination.

[0078] Figure 22 These are afterglow photographs of the polymer films prepared in Examples 1 and 2 before and after illumination. Detailed Implementation

[0079] The present invention will be further described in detail below through specific embodiments. Unless otherwise specified, the raw materials, reagents, or apparatus used in the embodiments can be obtained from conventional commercial sources or by existing technical methods. Unless otherwise specified, the experimental or testing methods are conventional methods in the art.

[0080] Example 1

[0081] In this embodiment, compound of formula (1) is prepared, and an organic long afterglow material is prepared using compound of formula (1) as the guest molecule. Then, a polymer film is prepared using the organic long afterglow material as the raw material through a hot pressing process.

[0082] 1. The method for synthesizing the compound of formula (1) is as follows:

[0083] 1) 4,7-Dibromo-5,6-dinitrophenyl[c][1,2,5]thiadiazole (1.50 g, 3.91 mmol) and tributyl(phenyl)stanane (4.3 g, 11.72 mmol) were added to toluene. After bubbling and purging for 30 min, bis(triphenylphosphine)palladium chloride was added. The reaction was carried out at 120 °C for 12 h. The reactants were basically reacted. The product was purified by column chromatography using petroleum ether:dichloromethane = 2:1 to obtain 1.2 g of pale yellow powder of intermediate product, with a yield of 81.08%.

[0084] The reaction route is shown below:

[0085] ;

[0086] 2) The intermediate product was added to 10 mL of a mixed solution of triethyl phosphite and chlorobenzene with a volume ratio of 1:1. The mixture was bubbled and aerated for 30 min, and then refluxed at 130 °C for 10 h. The raw material was basically completely reacted. The product was purified by column chromatography using petroleum ether: ethyl acetate = 1:1 to obtain the yellow powder of compound (1) with a yield of 50%.

[0087] The reaction route is shown below:

[0088] .

[0089] 2. The preparation steps of organic long afterglow materials are as follows:

[0090] S1. Weigh 2 mg of compound (1) and dissolve it in tetrahydrofuran to prepare an organic solution of compound (1) with a concentration of 1 mg / mL.

[0091] S2. Add 256 mg of melamine and 2.14 mL of 37 wt% formaldehyde aqueous solution to 0.1 mL of deionized water, then add triethanolamine to adjust the pH of the solution to 8-9, and heat at 95 °C for 2 h to form a clear melamine-formaldehyde resin prepolymer solution.

[0092] S3. Add the organic solution of compound (1) to the melamine-formaldehyde resin prepolymer solution, heat at 85°C for 2 hours, then heat at 130°C for 1 hour. After the solvent evaporates, the melamine-formaldehyde resin-based organic long afterglow material doped with compound (1) is obtained.

[0093] 3. The preparation steps of the polymer film are as follows:

[0094] The above-mentioned organic long afterglow material was heated and pressurized at 150°C and 16MPa for 10 minutes using a hot press to obtain a semi-transparent polymer film.

[0095] Example 2

[0096] In this embodiment, compound of formula (2) is prepared, and an organic long afterglow material is prepared using compound of formula (2) as the guest molecule. Then, a polymer film is prepared using the organic long afterglow material as the raw material through a hot pressing process.

[0097] 1. The method for synthesizing compound (2) is as follows:

[0098] Compound (1) prepared in Example 1 (0.14 g, 0.45 mmol) and sodium hydride (NaH) (0.12 g, 4.45 mmol) were added to 10 mL of ultra-dry tetrahydrofuran (THF). After dehydrogenation for 30 min, bromoethane (CH3CH2Br) (0.109 g, 4.45 mmol) was added, and the reaction solution was reacted at 66 °C for 12 h. The yield was purified by column chromatography using petroleum ether: ethyl acetate = 9:1 to obtain compound (2) as a solid powder with a yield of 70%.

[0099] The reaction route is shown below:

[0100] .

[0101] 2. The preparation steps of organic long afterglow materials are as follows:

[0102] S1. Weigh 2 mg of compound (2) and dissolve it in tetrahydrofuran to prepare an organic solution of compound (2) with a concentration of 1 mg / mL;

[0103] S2. Add 256 mg of melamine and 2.14 mL of 37 wt% formaldehyde aqueous solution to 0.1 mL of deionized water, then add triethanolamine to adjust the pH of the solution to 8-9, and heat at 95 °C for 2 h to form a clear melamine-formaldehyde resin prepolymer solution.

[0104] S3. Add the organic solution of compound (2) to the melamine-formaldehyde resin prepolymer solution, heat at 85°C for 2 hours, then heat at 130°C for 1 hour. After the solvent evaporates, the melamine-formaldehyde resin-based organic long afterglow material doped with compound (2) is obtained.

[0105] 3. The preparation steps of the polymer film are as follows:

[0106] The above-mentioned organic long afterglow material was heated and pressurized at 150°C and 16MPa for 10 minutes using a hot press to obtain a semi-transparent polymer film.

[0107] Characterization and performance testing

[0108] 1. The pure solid powders (microcrystals) of the compounds of formula (1) and formula (2) prepared in the examples were subjected to 1H NMR spectroscopy:

[0109] Figure 1 The 1H NMR spectrum of compound (1) in Example 1 is shown. Figure 2 The 1H NMR spectrum of compound (2) in Example 2 is obtained from... Figure 1 and Figure 2 It can be seen that the self-synthesized compounds of formula (1) and formula (2) have the target structure.

[0110] 2. The optical properties of the compounds of formula (1) and formula (2) prepared in Examples 1 and 2, as well as the organic long afterglow material, were tested to examine their afterglow emission spectra and afterglow lifetime. All tests were performed on an Edinburgh FLS980 steady-state and transient fluorescence spectrometer with an integrating sphere.

[0111] Figure 3 The steady-state emission spectra of the solid powders of compounds (1) and (2) in the embodiments are shown below. Figure 3 It can be seen that the compound of formula (1) has a high luminescence intensity only in the wavelength range of 475-650nm, and the compound of formula (2) has a high luminescence intensity only in the wavelength range of 450-600nm. That is, both the compounds of formula (1) and formula (2) emit only transient fluorescence and have no afterglow properties.

[0112] Figure 4 The graphs show the luminescence decay curves of the solid powders of compounds (1) and (2) in the embodiments. Figure 4 It can be seen that the duration of light emission of the solid powders of Formula (1) and Formula (2) after ultraviolet light excitation is very short, with fitted lifetime values ​​of 1.73 ns and 1.28 ns, respectively. That is, the solid powders of Formula (1) and Formula (2) do not have afterglow properties, and the light emission intensity decays rapidly.

[0113] Figure 5 The images show the steady-state emission spectra of the organic long afterglow materials in Examples 1 and 2. Figure 6 The images show the afterglow emission spectra of the organic long afterglow materials in Examples 1 and 2, derived from... Figure 5 and Figure 6 It can be seen that the steady-state luminescence of the organic long afterglow materials prepared in Examples 1 and 2 is mainly in the range of 450-600nm, and the delayed luminescence is in the range of 550-750nm.

[0114] Figure 7 The graphs show the afterglow decay curves of the organic long afterglow materials in Examples 1 and 2. Figure 7 It can be seen that the lifetimes of the maximum emission peaks in the delayed spectra of the organic long-afterglow materials in Examples 1 and 2 can reach the millisecond level and are greater than 100ms, with fitted lifetime values ​​of 0.15s and 0.12s, respectively, indicating that the materials have good long-afterglow luminescence performance.

[0115] Figure 8 The image shows the UV absorption curve of the organic long afterglow material in Example 1 as a function of illumination time. Figure 9 The UV absorption curve of the organic long afterglow material in Example 2 as a function of illumination time is shown below. Figure 8 and Figure 9It can be seen that as the illumination time increases, the ultraviolet absorption peaks of the organic long afterglow materials in Examples 1 and 2 both show an increasing trend, indicating that the materials exhibit photochromism.

[0116] Figure 10 The images show the steady-state emission spectrum and afterglow emission spectrum of the organic long-afterglow material before ultraviolet irradiation in Example 1. Figure 11 The images show the steady-state emission spectrum and afterglow emission spectrum of the organic long-afterglow material after ultraviolet irradiation in Example 1. Figure 10 and Figure 11 It can be seen that under aerobic conditions, after ultraviolet irradiation, the position of the maximum afterglow intensity of the organic long afterglow material in Example 1 shifted from 610nm to 638nm, and the afterglow color turned red after irradiation.

[0117] Figure 12 The images show the steady-state emission spectrum and afterglow emission spectrum of the organic long-afterglow material before ultraviolet irradiation in Example 2. Figure 13 The steady-state emission spectrum and afterglow emission spectrum of the organic long-afterglow material after ultraviolet irradiation in Example 2 are shown below. Figure 12 and Figure 13 It can be seen that under aerobic conditions, after ultraviolet irradiation, the position of the maximum afterglow intensity of the organic long afterglow material in Example 2 shifted from 632nm to 654nm, and the afterglow color turned red after irradiation.

[0118] Figure 14 This is a comparison of the afterglow emission spectra of the organic long afterglow material in Example 1 before and after illumination under oxygen-free conditions. Figure 14 It is known that when samples are prepared in an oxygen-free glove box and then hot-evacuated for 30 minutes to remove oxygen before testing, the organic long afterglow material in Example 1 did not undergo photophosphorescence discoloration when irradiated for 5 minutes under oxygen-free conditions.

[0119] Figure 15 This is a comparison of the afterglow emission spectra of the organic long afterglow material in Example 2 before and after illumination under oxygen-free conditions. Figure 15 It is known that when samples are prepared in an oxygen-free glove box and then hot-evacuated for 30 minutes to remove oxygen before testing, the organic long afterglow material in Example 2 did not undergo photophosphorescence discoloration when irradiated for 5 minutes under oxygen-free conditions.

[0120] Depend on Figures 12-15 It is known that the organic long afterglow material provided by the present invention exhibits photophosphorescence only under aerobic conditions, which indicates that the material can effectively resist oxygen quenching and has the potential to be applied to oxygen detection.

[0121] Figure 16 This is a comparison of the afterglow luminescence decay curves of the organic long-afterglow material before and after illumination in Example 1. Figure 16It can be seen that before illumination, the maximum emission peak fitting lifetime of the delayed spectrum of the organic long afterglow material in Example 1 was 0.16s, and after illumination it was 0.155s. The fitting lifetime value before and after illumination remained basically unchanged, indicating that the organic long afterglow material prepared in Example 1 has stable afterglow performance.

[0122] Figure 17 This is a comparison of the afterglow luminescence decay curves of the organic long afterglow material before and after illumination in Example 2. Figure 17 It can be seen that before illumination, the maximum emission peak fitting lifetime of the delayed spectrum of the organic long afterglow material in Example 2 was 0.123s, and after illumination it was 0.119s. The fitting lifetime value before and after illumination remained basically unchanged, indicating that the organic long afterglow material prepared in Example 2 also has stable afterglow performance.

[0123] Figure 18 This is a diagram showing the afterglow color change stability of the organic long afterglow material in Example 1. Figure 18 It can be seen that the organic long afterglow material in Example 1 has good reversibility under light irradiation for 5 minutes and heating at 100°C for 10 seconds.

[0124] Figure 19 This is a diagram showing the afterglow color change stability of the organic long afterglow material in Example 2. Figure 19 It can be seen that the organic long afterglow material in Example 2 has good reversibility under light irradiation for 5 minutes and heating at 100°C for 10 seconds.

[0125] Figure 20 This is the CIE chromaticity diagram of the organic long-afterglow material in Example 1 during 0-5 minutes of illumination. Figure 21 The CIE chromaticity diagram of the organic long-afterglow material in Example 2 during 0-5 minutes of illumination is obtained from... Figure 20 and Figure 21 As can be seen from the CIE chromaticity diagrams of the organic long afterglow materials in Examples 1 and 2, the spectral lines all show a trend of gradually shifting towards the red light direction as the illumination time increases, indicating that the materials will exhibit a red or dark red afterglow after illumination, and have photo-induced phosphorescence properties.

[0126] Figure 22 These are afterglow photographs of the polymer films prepared in Examples 1 and 2 before and after illumination, wherein... Figure 22 (a) The polymer film in Example 1 before light exposure Figure 22 (b) The polymer film in Example 1 after being exposed to light Figure 22 (c) The polymer film in Example 2 before light exposure. Figure 22 (d) The polymer film in Example 2 after light exposure. Figure 22It can be seen that under aerobic conditions, the afterglow color of the polymer films in Examples 1 and 2 deepens after illumination, while under oxygen-free conditions, the afterglow color of the polymer films does not change before and after illumination. This indicates that the material can effectively resist the phosphorescence quenching behavior of oxygen and has the characteristic of light-induced afterglow color change. It can be used for oxygen detection and to test the qualification of oxygen-free devices.

Claims

1. An organic long afterglow material, characterized in that, It includes a host component and guest molecules doped in the host component; wherein the host component includes melamine-formaldehyde resin; and the guest molecules are selected from compounds of formula (1), compounds of formula (2), or combinations thereof. Equation (1) Equation (2).

2. The organic long afterglow material according to claim 1, characterized in that, In the organic long afterglow material, the mass fraction of the guest molecule is 0.001%-5%.

3. The method for preparing the organic long afterglow material according to claim 1 or 2, characterized in that, Includes the following steps: The guest molecule solution is mixed with the melamine-formaldehyde resin prepolymer solution and heated to react, thus obtaining the organic long afterglow material.

4. The preparation method according to claim 3, characterized in that, The concentration of the guest molecule in the guest molecule solution is 1-4 mg / mL.

5. The preparation method according to claim 3, characterized in that, The pH value of the melamine-formaldehyde resin prepolymer solution is 8-10.

6. A polymer film, characterized in that, The raw materials for preparing the polymer film include the organic long afterglow material as described in claim 1 or 2.

7. The application of the organic long afterglow material according to claim 1 or 2, or the polymer film according to claim 6, in oxygen detection.

Images