Preparation method and display application of organic long-afterglow hydrogel with mechanical stability
By preparing an organic long-afterglow hydrogel in an aqueous phase and mixing pullulan-coated hydrophilic particles with a prepolymer solution, the problems of poor mechanical stability and easy quenching of afterglow are solved, uniform luminescence and stable afterglow are achieved, the preparation process is simplified and toxicity is reduced.
Patent Information
- Application Number
- CN202510790723.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-06-13
- Publication Date
- 2025-10-03
AI Technical Summary
Existing organic long-afterglow hydrogels have problems of poor mechanical stability during the preparation process and easy quenching of afterglow during use. In addition, the traditional preparation method uses heavy metal complexes, which are costly and highly biologically toxic. The mechanical stability of the hydrogels in the hydrophobic microenvironment under physical action is also poor.
Organic long afterglow particles are mixed with prepolymer liquid, and the hydrophilic organic long afterglow particles with pullulan as the shell, main material and guest material as the core are uniformly dispersed in the aqueous phase. Acrylamide is used to cross-link to form polyacrylamide to prepare an organic long afterglow hydrogel with good mechanical stability.
An organic long-afterglow hydrogel with uniform luminescence and stable afterglow performance is achieved, which has stretchability and adhesion. The preparation method is simple and environmentally friendly, and avoids the use of heavy metals.
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Figure CN120737367A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of organic long-afterglow materials, and in particular relates to a preparation method of a mechanically stable organic long-afterglow hydrogel and its display application. Background Art
[0002] Organic long-lasting glow materials are materials that continue to emit light for a period of time after the excitation light source is turned off. Due to their unique photoluminescent properties, they are widely used in fields such as bioimaging, organic light-emitting devices (OLEDs), and information encryption. Common organic long-lasting glow materials include organic long-lasting glow films and organic long-lasting glow hydrogels. Organic long-lasting glow films are sensitive to environmental factors such as temperature, humidity, and oxygen. The afterglow effect may decline with long-term use or when affected by external environmental factors. Organic long-lasting glow hydrogels have attracted much attention due to their excellent optical and mechanical properties.
[0003] Currently, there are two main methods for preparing organic long-lasting glow hydrogels. The first method involves introducing phosphorescent metal complexes that emit phosphorescent light in water into the hydrogel. In this method, phosphorescent metal complexes are typically composed of heavy metal atoms (such as platinum, iridium, and ruthenium) coordinated with organic ligands. Due to their heavy atom effect, these phosphorescent metal complexes can promote intersystem crossing (ISC) from singlet excitons to triplet excitons, thereby achieving efficient phosphorescence emission. However, these complexes suffer from disadvantages such as short phosphorescence lifetimes, high costs, and high biotoxicity. The second method involves creating a hydrophobic microenvironment through physical interactions, such as hydrophobic and electrostatic interactions, between the host and guest materials. In this method, physical interactions can partially separate the luminescent chromophore from water and create a hydrophobic, rigid microenvironment within the hydrogel. However, the resulting organic long-lasting glow hydrogels suffer from poor mechanical stability, such as afterglow quenching during stretching. Summary of the Invention
[0004] In view of the shortcomings of the prior art, the present invention aims to provide a method for preparing an organic long-lasting hydrogel.
[0005] Another object of the present invention is to provide an organic long-lasting hydrogel obtained by the above preparation method.
[0006] The purpose of the present invention is achieved through the following technical solutions.
[0007] A method for preparing an organic long-afterglow hydrogel comprises: mixing organic long-afterglow particles and a prepolymer solution until uniform, standing (thermal initiation) at 50-60°C for 1-5 hours to allow acrylamide to crosslink to form polyacrylamide, thereby obtaining the organic long-afterglow hydrogel, wherein the prepolymer solution comprises a polymer compound, a crosslinking accelerator, and an initiator; the polymer compound comprises acrylamide; and the ratio of the organic long-afterglow particles to the polymer compound in the prepolymer solution is 1:(5-7.5) by mass; and the organic long-afterglow particles are coated with pullulan.
[0008] In the above technical solution, the raw materials for preparing organic long afterglow particles include: a host material, a guest material and a dispersant, the host material is triphenylphosphine, the guest material is at least one of tetraphenylbenzenediamine and acridone, and the dispersant is pullulan. Calculated by mass, the ratio of the guest material, the host material and the dispersant is 1: (100~500): (200~500).
[0009] In the above technical solution, the polymer compound further includes: a first substance, which is sodium alginate or polyvinyl alcohol.
[0010] In the above technical solution, the organic long afterglow particles and the prepolymer solution are mixed and stirred at room temperature for 10 to 30 minutes until they are uniform.
[0011] In the above technical solution, the ratio of the polymer compound, the cross-linking accelerator and the initiator is (500-1200):1:(10-20) in parts by mass.
[0012] In the above technical solution, the cross-linking accelerator is N,N-methylenebisacrylamide, and the initiator is ammonium persulfate.
[0013] In the above technical solution, the method for obtaining the prepolymer solution includes: adding a cross-linking accelerator, a polymer compound and an initiator into water, and stirring at room temperature for 30 to 60 minutes to obtain the prepolymer solution.
[0014] In the above technical solution, when the polymer compound is acrylamide, the ratio of the crosslinking accelerator, acrylamide, initiator and water is 1:(500-1000):(10-20):(3000-6000) in parts by mass.
[0015] In the above technical solution, when the polymer compound is a mixture of acrylamide and sodium alginate, the ratio of the crosslinking accelerator, acrylamide, sodium alginate, initiator and water is 1: (500-1000): (40-80): (10-20): (3000-6000) by mass.
[0016] In the above technical solution, when the polymer compound is a mixture of acrylamide and polyvinyl alcohol, the ratio of the crosslinking accelerator, polyvinyl alcohol, acrylamide, initiator and water is 1: (300-600): (500-1000): (10-20): (3000-6000) by mass.
[0017] In the above technical solution, the particle size of the organic long afterglow particles is 5 to 50 microns.
[0018] In the above technical solution, the method for preparing organic long afterglow particles comprises: heating a first solution at 105-120° C. for 5-10 minutes under stirring, cooling the temperature to room temperature under stirring, and filtering to obtain the organic long afterglow particles, wherein the first solution comprises: a host material, a guest material, and a dispersant aqueous solution, the dispersant aqueous solution being a mixture of a dispersant and water, and the ratio of the guest material, the host material, and the dispersant in the dispersant aqueous solution being 1:(100-500):(200-500) in parts by mass.
[0019] In the above technical solution, the concentration of the dispersant in the dispersant aqueous solution is 0.5 to 15 wt%.
[0020] When the guest material is tetraphenylbenzenediamine, the method for obtaining the first solution includes: mixing the host material, the guest material and the dispersant aqueous solution, and stirring at room temperature for 5 to 20 minutes until uniform, to obtain the first solution.
[0021] When the guest material is acridone, the method for obtaining the first solution includes: adding the host material and the guest material to anhydrous ethanol, stirring at 80-100°C for 10-20 minutes, drying to constant weight to obtain a premix, adding the premix to a dispersant aqueous solution, stirring at room temperature for 5-20 minutes until uniform, and obtaining the first solution.
[0022] In the above technical solution, the method for obtaining the dispersant aqueous solution comprises: adding the dispersant to water, stirring at room temperature for 1 to 2 hours, and obtaining the dispersant aqueous solution.
[0023] The organic long afterglow hydrogel obtained by the above preparation method.
[0024] Application of the above-mentioned organic long afterglow hydrogel in luminescent display.
[0025] Compared with the prior art, the present invention has the following beneficial effects:
[0026] (1) The present invention uses hydrophilic pullulan, a host material, and a guest material to prepare hydrophilic organic long-lasting glow particles with pullulan as the shell and the host material and guest material as the core. The hydrophilic organic long-lasting glow particles can be evenly dispersed in a variety of prepolymer solutions to prepare different types of organic long-lasting glow hydrogels with uniform luminescence. Compared with the method of preparing long-lasting glow hydrogels using electrostatic interactions, this method is more universal.
[0027] (2) The organic long afterglow hydrogel obtained by blending hydrophilic organic long afterglow particles with prepolymer solution has stable afterglow performance, and the afterglow will not be quenched during mechanical operations such as stretching.
[0028] (3) The preparation method of the present invention is simple and is carried out in an aqueous phase, which is more environmentally friendly than the preparation method using highly toxic organic solvents such as dichloromethane and N,N-dimethylformamide.
[0029] (4) The organic long afterglow hydrogel prepared by the present invention can achieve stretchability and adhesion, and has the advantage of wide application. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Figure 1 This is a macroscopic LPL image of the organic long afterglow hydrogel prepared in Example 1;
[0031] Figure 2 This is a scanning electron microscope photograph of the organic long afterglow hydrogel prepared in Example 1;
[0032] Figure 3 This is a macroscopic LPL image of the organic long afterglow hydrogel prepared in Example 2;
[0033] Figure 4 This is a scanning electron microscope photograph of the organic long afterglow hydrogel prepared in Example 2;
[0034] Figure 5 This is a macroscopic LPL image of the organic long afterglow hydrogel prepared in Example 3;
[0035] Figure 6 This is a scanning electron microscope photograph of the organic long afterglow hydrogel prepared in Example 3;
[0036] Figure 7 This is a macroscopic LPL image of the organic long afterglow hydrogel prepared in Example 4;
[0037] Figure 8 This is a scanning electron microscope photograph of the organic long afterglow hydrogel prepared in Example 4;
[0038] Figure 9 Fluorescence and afterglow photos of the organic long afterglow hydrogel prepared in Example 3 before and after stretching;
[0039] Figure 10 This is the afterglow attenuation spectra of the organic long afterglow hydrogel prepared in Example 3 before and after stretching;
[0040] Figure 11 Fluorescence and afterglow photos of the organic long afterglow hydrogel prepared in Example 1 before and after stretching;
[0041] Figure 12 Fluorescence and afterglow photos of the organic long afterglow hydrogel prepared in Example 2 before and after stretching;
[0042] Figure 13 Fluorescence and afterglow photos of the organic long afterglow hydrogel prepared in Example 4 before and after stretching;
[0043] Figure 14 Afterglow photograph of the organic long afterglow hydrogel prepared in Example 3 applied to projection display;
[0044] Figure 15 This is a macroscopic LPL image of the hydrogel prepared in Comparative Example 1;
[0045] Figure 16 This is a macroscopic LPL image of the organic long afterglow hydrogel prepared in Comparative Example 2;
[0046] Figure 17 This is a macroscopic LPL image of the organic long afterglow hydrogel prepared in Comparative Example 3;
[0047] Figure 18 This is a macroscopic LPL image of the organic long afterglow hydrogel prepared in Comparative Example 4;
[0048] Figure 19 The phosphorescence spectrum of the organic long afterglow hydrogel prepared in Example 1;
[0049] Figure 20 This is the phosphorescence spectrum of the organic long afterglow hydrogel prepared in Example 2;
[0050] Figure 21 This is the phosphorescence spectrum of the organic long afterglow hydrogel prepared in Example 3;
[0051] Figure 22 This is the phosphorescence spectrum of the organic long afterglow hydrogel prepared in Example 4;
[0052] Figure 23 This is the SEM of the organic long afterglow particles prepared in Example 1;
[0053] Figure 24 This is the SEM of the organic long afterglow particles prepared in Example 4. DETAILED DESCRIPTION
[0054] The technical solution of the present invention is further described below with reference to specific embodiments.
[0055] The raw material information involved in the following examples and comparative examples is as follows:
[0056] Triphenylphosphine, acridone, tetraphenylbenzene diamine, pullulan, sodium alginate, and xanthan gum were purchased from Jinxiens Biochemical Technology Co., Ltd. Triphenylphosphine has a CAS number of 603-35-0 and a molecular weight of 262.29; acridone has a CAS number of 578-95-0 and a molecular weight of 195.22; tetraphenylbenzene diamine has a CAS number of 15546-43-7 and a molecular weight of 488.62; pullulan has a CAS number of 9057-02-7; sodium alginate has a CAS number of 9005-38-3; and xanthan gum has a CAS number of 11138-66-2 and a molecular weight of 241.11496.
[0057] Polyvinyl alcohol, acrylamide, N,N-methylenebisacrylamide, ammonium persulfate, carrageenan, and oxidized starch were purchased from Shanghai Myril Biochemical Technology Co., Ltd. Polyvinyl alcohol (CAS: 9002-89-5); acrylamide (CAS: 79-06-1, molecular weight: 71.08); N,N-methylenebisacrylamide (CAS: 110-26-9, molecular weight: 154.17); ammonium persulfate (CAS: 7727-54-0, molecular weight: 228.20); carrageenan (CAS: 11114-20-8); and oxidized starch (CAS: 65996-62-5).
[0058] Example 1
[0059] A method for preparing an organic long-afterglow hydrogel comprises: mixing organic long-afterglow particles and a prepolymer solution, stirring at room temperature at a speed of 300 r / min for 30 minutes until uniform, and standing (thermal initiation) at 50° C. for 1 hour to allow acrylamide to crosslink to form polyacrylamide (network), thereby obtaining the organic long-afterglow hydrogel, wherein the prepolymer solution comprises: a polymer compound, a crosslinking accelerator (N,N-methylenebisacrylamide), an initiator (ammonium persulfate) and water, the polymer compound being acrylamide, and the ratio of the organic long-afterglow particles to the polymer compound in the prepolymer solution being 1:5 in parts by mass;
[0060] The method for preparing the above-mentioned organic long afterglow particles comprises: heating a first solution in an oil bath at 105° C. while stirring for 10 minutes (stirring speed is 900 r / min), then cooling the solution while stirring (stirring speed is 900 r / min) to room temperature to obtain organic long afterglow particles uniformly dispersed in water, filtering to obtain organic long afterglow particles with an average particle size of 10 microns; wherein, the method for obtaining the first solution comprises: mixing a host material, a guest material and a dispersant aqueous solution, stirring at a speed of 300 r / min at room temperature for 5 minutes until uniform, to obtain a first solution, in which the ratio of the guest material, the host material and the dispersant in the dispersant aqueous solution is 1:100:350 by mass, and the method for obtaining the dispersant aqueous solution comprises: adding the dispersant to deionized water, stirring at a speed of 300 r / min at room temperature for 1 hour to obtain the dispersant aqueous solution, and the concentration of the dispersant in the dispersant aqueous solution is 13 wt%. The main material is triphenylphosphine, the guest material is tetraphenylbenzene diamine, and the dispersant is pullulan.
[0061] The method for obtaining the above-mentioned prepolymer liquid (polyacrylamide prepolymer liquid) includes: adding N,N-methylenebisacrylamide, acrylamide and ammonium persulfate to deionized water, stirring at a speed of 300 r / min for 30 minutes at room temperature to obtain a polyacrylamide prepolymer liquid, wherein the ratio of N,N-methylenebisacrylamide, acrylamide, ammonium persulfate and water is 1:800:10:5000 by mass.
[0062] Example 2
[0063] A method for preparing an organic long-afterglow hydrogel comprises: mixing the organic long-afterglow particles prepared in Example 1 with a prepolymer solution, stirring the mixture at room temperature for 30 minutes until uniform, and thermally initiating (standing) the mixture at 50° C. for 5 hours to crosslink acrylamide to form polyacrylamide, thereby obtaining the organic long-afterglow hydrogel. The prepolymer solution comprises a polymer compound, a crosslinking accelerator (N,N-methylenebisacrylamide), and an initiator (ammonium persulfate). The polymer compound is a mixture of acrylamide and sodium alginate. The ratio of the organic long-afterglow particles to the polymer compound in the prepolymer solution is 1:5.4 in parts by mass.
[0064] The method for obtaining the above-mentioned prepolymer liquid (sodium alginate-polyacrylamide prepolymer liquid) includes: adding N,N-methylenebisacrylamide, acrylamide, sodium alginate and ammonium persulfate to deionized water, stirring at a speed of 300 r / min for 30 minutes at room temperature to obtain a sodium alginate-polyacrylamide prepolymer liquid, wherein the ratio of N,N-methylenebisacrylamide, acrylamide, sodium alginate, ammonium persulfate and water is 1:800:65:10:5000 by mass.
[0065] Example 3
[0066] A method for preparing an organic long-afterglow hydrogel comprises: mixing the organic long-afterglow particles prepared in Example 1 with a prepolymer solution, stirring at room temperature for 30 minutes until uniform, and thermally initiating (standing) at 50° C. for 5 hours to crosslink acrylamide to form polyacrylamide, thereby obtaining the organic long-afterglow hydrogel, wherein the prepolymer solution comprises: a polymer compound, a crosslinking accelerator (N,N-methylenebisacrylamide) and an initiator (ammonium persulfate), the polymer compound being a mixture of acrylamide and polyvinyl alcohol, and the ratio of the organic long-afterglow particles to the polymer compound in the prepolymer solution being 1:7.5 in parts by mass.
[0067] The method for obtaining the above-mentioned prepolymer liquid (polyvinyl alcohol-polyacrylamide prepolymer liquid) includes: adding N,N-methylenebisacrylamide, polyvinyl alcohol, acrylamide and ammonium persulfate to deionized water, stirring at a speed of 300 r / min at room temperature for 60 minutes to obtain a polyvinyl alcohol-polyacrylamide prepolymer liquid, wherein the ratio of N,N-methylenebisacrylamide, polyvinyl alcohol, acrylamide, ammonium persulfate and water is 1:400:800:10:5000 by mass.
[0068] Example 4
[0069] A method for preparing an organic long-afterglow hydrogel comprises: mixing organic long-afterglow particles and the prepolymer solution of Example 1, stirring at room temperature for 30 minutes until uniform, and thermally initiating (standing) at 50° C. for 1 hour to crosslink acrylamide to form polyacrylamide, thereby obtaining the organic long-afterglow hydrogel, wherein the ratio of the organic long-afterglow particles to the polymer compound in the prepolymer solution is 1:5 by mass;
[0070] The method for preparing the organic long afterglow particles in Example 4 comprises: heating the first solution in an oil bath at 105° C. with stirring for 10 minutes (at a stirring speed of 900 rpm), then cooling the solution with stirring (at a stirring speed of 900 rpm) to room temperature to obtain organic long afterglow particles uniformly dispersed in water, and filtering to obtain organic long afterglow particles with an average particle size of 10 μm.
[0071] Among them, the method for obtaining the first solution includes: adding the main material and the guest material to anhydrous ethanol (the ratio of the mass fraction of the main material to the volume fraction of anhydrous ethanol is 100:2, the unit of mass fraction is mg, and the unit of volume fraction is mL), stirring at 80°C and 300r / min for 20 minutes, and drying at 60°C to constant weight to obtain a premix, adding the premix to the dispersant aqueous solution, and stirring at 300r / min for 5 minutes at room temperature to obtain a first solution, wherein the main material is triphenylphosphine, the guest material is acridone, and the dispersant is pullulan. By mass fraction, the ratio of the guest material, the main material and the dispersant in the dispersant aqueous solution is 1:100:350. The method for obtaining the dispersant aqueous solution includes: adding the dispersant to deionized water, stirring at 300r / min for 1 hour at room temperature to obtain a dispersant aqueous solution, and the concentration of the dispersant in the dispersant aqueous solution is 13wt%.
[0072] Comparative Example 1
[0073] A method for preparing a hydrogel is basically the same as that of Example 1, except that "organic long afterglow particles" are replaced with "tetraphenylbenzene diamine".
[0074] Comparative Example 2
[0075] A method for preparing an organic long-lasting hydrogel is basically the same as that in Example 1, except that "pullulan" is replaced by "xanthan gum".
[0076] Comparative Example 3
[0077] A method for preparing an organic long-lasting hydrogel is basically the same as that in Example 1, except that "pullulan" is replaced by "carrageenan".
[0078] Comparative Example 4
[0079] A method for preparing an organic long-lasting hydrogel is basically the same as that in Example 1, except that "pullulan" is replaced by "oxidized starch".
[0080] The thickness of the organic long afterglow hydrogel and the hydrogel prepared in the above examples and comparative examples is about 5 mm.
[0081] At room temperature, the organic long afterglow hydrogel prepared in Example 1 was irradiated (excited) with a 365 nm ultraviolet lamp for 1 second, and the ultraviolet lamp was turned off to obtain the following Figure 1 The macro LPL picture shown, Figure 1 From left to right in the figure are the macroscopic LPL images when the UV lamp is excited, and 1s, 3s, and 5s after the UV lamp is turned off. Figure 1As shown, the organic long afterglow hydrogel prepared in Example a 1 emits light uniformly, and the afterglow time is 5s.
[0082] Figure 2 This is a scanning electron microscope photo of the organic long afterglow hydrogel prepared in Example 1. Figure 2 It can be seen that the organic long afterglow hydrogel has a more porous structure.
[0083] At room temperature, the organic long afterglow hydrogel prepared in Example 2 was irradiated (excited) with a 365 nm ultraviolet lamp for 1 second, and the ultraviolet lamp was turned off to obtain the following Figure 3 The macro LPL picture shown, Figure 3 From left to right in the figure are the macroscopic LPL images when the UV lamp is excited, and 1s, 3s, and 5s after the UV lamp is turned off. Figure 3 As shown, the organic long afterglow hydrogel prepared in Example 2 emits light uniformly, and the afterglow time is 5s.
[0084] Figure 4 This is a scanning electron microscope photo of the organic long afterglow hydrogel prepared in Example 2. Figure 4 It can be seen that the organic long afterglow hydrogel has a more porous structure.
[0085] At room temperature, the organic long afterglow hydrogel prepared in Example 3 was irradiated (excited) with a 365 nm ultraviolet lamp for 1 second, and the ultraviolet lamp was turned off to obtain the following Figure 5 The macro LPL picture shown, Figure 5 From left to right in the figure are the macroscopic LPL images when the UV lamp is excited, and 1s, 3s, and 5s after the UV lamp is turned off. Figure 5 As shown, the organic long afterglow hydrogel prepared in Example 3 emits light uniformly, and the afterglow time is 5s.
[0086] Figure 6 This is a scanning electron microscope photo of the organic long afterglow hydrogel prepared in Example 3. Figure 6 It can be seen that the organic long afterglow hydrogel has a more porous structure.
[0087] At room temperature, the organic long afterglow hydrogel prepared in Example 4 was irradiated (excited) with a 365 nm ultraviolet lamp for 1 second, and the ultraviolet lamp was turned off to obtain the following Figure 7 The macro LPL picture shown, Figure 7 From left to right in the figure are the macroscopic LPL images when the UV lamp is excited, and 1s, 2s, and 3s after the UV lamp is turned off. Figure 7 As shown, the organic long afterglow hydrogel prepared in Example 4 emits light uniformly, and the afterglow time is 3s.
[0088] Figure 8 This is a scanning electron microscope photo of the organic long afterglow hydrogel prepared in Example 4. Figure 8 It can be seen that the organic long afterglow hydrogel has a more porous structure.
[0089] The organic long afterglow hydrogel prepared in Example 3 was stretched by hand to 10 times, and the organic long afterglow hydrogel before stretching (0% stretching) and after stretching (1000% stretching) was irradiated (excited) with a 365nm ultraviolet lamp for 1s. Figure 9 "UV ON") and 1s after turning off the UV lamp ( Figure 9 Photos with "UV OFF" in the Figure 9 As shown by Figure 9 It can be seen that the afterglow effect of the organic long afterglow hydrogel does not change before and after stretching.
[0090] The afterglow performance attenuation diagram of the organic long afterglow hydrogel prepared in Example 3 before and after stretching was measured by an ocean fiber optic spectrometer. Figure 10 As shown, Figure 10 "0% stretching" represents the organic long afterglow hydrogel before stretching, "1000% stretching" represents the organic long afterglow hydrogel after stretching, -2 to 0s is the light excitation stage, and 0 to 5s is the afterglow stage (the long afterglow luminescence of the organic long afterglow hydrogel after the UV lamp is removed). Figure 10 It can be seen that the afterglow time of the organic long afterglow hydrogel prepared in Example 3 before and after stretching is about 5s, which is similar to the afterglow time observed in the macroscopic LPL image. Figure 10 It can be seen that the afterglow of the organic long afterglow hydrogel will not be quenched after stretching, and it has operational stability.
[0091] The organic long afterglow hydrogel prepared in Example 1 was stretched by hand to 2.5 times, and the organic long afterglow hydrogel before and after stretching was irradiated (excited) with a 365nm ultraviolet lamp for 1s. When the ultraviolet lamp was excited ( Figure 11 "UV ON") and 1s after turning off the UV lamp ( Figure 11 Photos with "UV OFF" in the Figure 11 As shown by Figure 11 It can be seen that the afterglow effect of the organic long afterglow hydrogel does not change before and after stretching.
[0092] The organic long afterglow hydrogel prepared in Example 2 was stretched by hand to 0.5 times, and the organic long afterglow hydrogel before and after stretching was irradiated (excited) with a 365nm ultraviolet lamp for 1s. When the ultraviolet lamp was excited ( Figure 12 "UV ON") and 1s after turning off the UV lamp ( Figure 12 Photos with "UV OFF" in the Figure 12 As shown by Figure 12 It can be seen that the afterglow effect of the organic long afterglow hydrogel does not change before and after stretching.
[0093] The organic long afterglow hydrogel prepared in Example 4 was stretched by hand to 2.5 times, and the organic long afterglow hydrogel before and after stretching was irradiated (excited) with a 365nm ultraviolet lamp for 1s. When the ultraviolet lamp was excited ( Figure 13 "UV ON") and 1s after turning off the UV lamp ( Figure 13 Photos with "UV OFF" in the Figure 13 As shown by Figure 13 It can be seen that the afterglow effect of the organic long afterglow hydrogel does not change before and after stretching.
[0094] The organic long afterglow hydrogel prepared in Example 3 of 5 cm*5 cm was stretched into a 10 cm*10 cm transparent film and used as a projection screen. A 365 nm ultraviolet lamp was used as an excitation light source to irradiate the projection screen through a film for 1 second (adjust the appropriate focal length so that the light of the excitation light source passes through the film corresponding to the projection screen and the focusing lens in sequence, and is finally projected onto the projection screen. The hollow patterns of "roses", "maple leaves" and "flying birds" are formed on the film). The excitation light source is turned off. Figure 14 As shown, a film with a "rose" hollow pattern produced a "rose" afterglow pattern, a film with a "maple leaf" hollow pattern produced a "maple leaf" afterglow pattern, and a film with a "flying bird" hollow pattern produced a "flying bird" afterglow pattern. This demonstrates that organic long-lasting hydrogels can be used for projection displays.
[0095] At room temperature, the organic long afterglow hydrogel prepared in Example 1 was irradiated (excited) with a 365nm ultraviolet lamp for 1s, and the ultraviolet lamp was turned off to obtain the following Figure 15 The macro LPL picture shown, Figure 15 From left to right in the figure are the macroscopic LPL images at the time of UV lamp excitation and at 0s after the UV lamp is turned off. Figure 15 As shown in FIG, there is no afterglow after the UV lamp is turned off. In Comparative Example 1, only tetraphenylbenzene diamine and prepolymer solution are mixed, and the prepared hydrogel has no afterglow property, indicating that the organic long afterglow hydrogel cannot be prepared by simply mixing the guest material with the prepolymer solution.
[0096] At room temperature, the organic long afterglow hydrogel prepared in Example 2 was irradiated (excited) with a 365nm ultraviolet lamp for 1s, and the ultraviolet lamp was turned off to obtain the following Figure 16 The macro LPL picture shown, Figure 16 From left to right in the figure are the macroscopic LPL images when the UV lamp is excited, and 1s, 3s, and 5s after the UV lamp is turned off. Figure 16 As shown, the organic long afterglow hydrogel prepared in Comparative Example 2 cannot achieve uniform afterglow luminescence. Figure 16The small and medium white spots are organic long afterglow crystals that are not evenly dispersed, indicating that the organic long afterglow particles prepared using xanthan gum as a dispersant cannot be evenly dispersed in the polyacrylamide prepolymer solution.
[0097] At room temperature, the organic long afterglow hydrogel prepared in Comparative Example 3 was irradiated (excited) with a 365nm ultraviolet lamp for 1s, and the ultraviolet lamp was turned off to obtain Figure 17 The macro LPL picture shown, Figure 17 From left to right in the figure are the macroscopic LPL images when the UV lamp is excited, and 1s, 3s, and 5s after the UV lamp is turned off. Figure 17 As shown, the organic long afterglow hydrogel prepared in Comparative Example 3 cannot achieve uniform afterglow luminescence, indicating that the organic long afterglow particles prepared using carrageenan as a dispersant cannot be uniformly dispersed in the polyacrylamide prepolymer solution.
[0098] At room temperature, the organic long afterglow hydrogel prepared in Comparative Example 4 was irradiated (excited) with a 365nm ultraviolet lamp for 1s, and the ultraviolet lamp was turned off to obtain Figure 18 The macro LPL picture shown, Figure 18 From left to right in the figure are the macroscopic LPL images when the UV lamp is excited, and 1s, 3s, and 5s after the UV lamp is turned off. Figure 18 As shown, the organic long afterglow hydrogel prepared in Comparative Example 4 cannot achieve uniform afterglow luminescence, indicating that the organic long afterglow particles prepared using oxidized starch as a dispersant cannot be uniformly dispersed in the polyacrylamide prepolymer solution.
[0099] Pullulan, xanthan gum, carrageenan and oxidized starch are all hydrophilic compounds, but only the organic long-afterglow hydrogel prepared with pullulan as a dispersant can exhibit uniform afterglow luminescence. This is because pullulan, as a straight-chain polysaccharide without a branched structure, has good solubility and structural flexibility and does not gel itself, and has better affinity with the luminescent crystal core (i.e., the host material and the guest material).
[0100] The phosphorescence spectra of the organic long afterglow hydrogels prepared in Examples 1 to 4 were measured by a phosphorescence spectrometer (model: Edinburgh FLS980). The phosphorescence spectra of the organic long afterglow hydrogels prepared in Example 1 are as follows: Figure 19 As shown, the phosphorescence spectrum of the organic long afterglow hydrogel prepared in Example 2 is as follows Figure 20 As shown, the phosphorescence spectrum of the organic long afterglow hydrogel prepared in Example 3 is as follows Figure 21 As shown, the phosphorescence spectrum of the organic long afterglow hydrogel prepared in Example 4 is as follows Figure 22 As shown. Figure 22It can be seen that the organic long afterglow hydrogel prepared in Example 4 has two emission peaks, namely a TADF peak at 425 nm and an RTP peak at 490 nm. The reason for the formation of the two emission peaks is that acridone undergoes reverse intersystem crossing.
[0101] Figure 23 This is the SEM of the organic long afterglow particles prepared in Example 1. Figure 24 This is a SEM image of the organic long afterglow particles prepared in Example 4. The SEM shows that the organic long afterglow particles are a core-shell structure, with pullulan as the shell and the host material and guest material as the core.
[0102] The above is an exemplary description of the present invention. It should be noted that, without departing from the core of the present invention, any simple deformation, modification or other equivalent replacement that can be made by other skilled in the art without expending creative labor falls within the scope of protection of the present invention.
Claims
1. A method for preparing an organic long afterglow hydrogel, characterized in that: include: The organic long afterglow particles and the prepolymer liquid are mixed until uniform, and allowed to stand at 50-60°C for 1-5 hours to allow the acrylamide to crosslink to form polyacrylamide, thereby obtaining an organic long afterglow hydrogel, wherein the prepolymer liquid comprises: a polymer compound, a crosslinking accelerator and an initiator, the polymer compound comprises: acrylamide, and the ratio of the organic long afterglow particles to the polymer compound in the prepolymer liquid is 1:(5-7.5) by mass, and the organic long afterglow particles are coated with pullulan.
2. The preparation method according to claim 1, characterized in that The polymer compound further includes: a first substance, which is sodium alginate or polyvinyl alcohol.
3. The preparation method according to claim 1, characterized in that Calculated by mass, the ratio of the polymer compound, the cross-linking accelerator and the initiator is (500-1200):1:(10-20).
4. The preparation method according to claim 1, characterized in that The raw materials for preparing organic long afterglow particles include: a host material, a guest material and a dispersant, wherein the host material is triphenylphosphine, the guest material is at least one of tetraphenylbenzenediamine and acridone, and the dispersant is pullulan. Calculated by mass, the ratio of the guest material, the host material and the dispersant is 1: (100-500): (200-500).
5. The preparation method according to claim 1, characterized in that The cross-linking accelerator is N,N-methylenebisacrylamide, and the initiator is ammonium persulfate.
6. The preparation method according to claim 1, characterized in that The method for obtaining the prepolymer solution comprises: adding a cross-linking accelerator, a high molecular compound and an initiator into water, and stirring the mixture at room temperature for 30 to 60 minutes to obtain the prepolymer solution.
7. The preparation method according to claim 1, characterized in that The particle size of the organic long afterglow particles is 5 to 50 microns.
8. The preparation method according to claim 4, characterized in that The method for preparing organic long afterglow particles comprises: heating a first solution at 105-120° C. for 5-10 minutes under stirring, cooling the temperature to room temperature under stirring, and filtering to obtain the organic long afterglow particles, wherein the first solution comprises: a host material, a guest material, and a dispersant aqueous solution, the dispersant aqueous solution being a mixture of a dispersant and water, and the ratio of the guest material, the host material, and the dispersant in the dispersant aqueous solution being 1:(100-500):(200-500) in parts by mass.
9. The organic long afterglow hydrogel obtained by the preparation method according to any one of claims 1 to 8.
10. Use of the organic long afterglow hydrogel according to claim 9 in luminescent display.