Long-life afterglow polymer material and preparation method and application thereof
Long-afterglow polymer materials were prepared by combining tris(4-boronic acid pinene ester phenyl)amine and aromatic polyesters, which solved the problem of insufficient afterglow time and intensity of existing materials, and achieved 12-hour long afterglow and high-intensity afterglow under sunlight excitation, which is suitable for multiple application fields.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SUN YAT SEN UNIV
- Filing Date
- 2024-12-23
- Publication Date
- 2026-05-29
AI Technical Summary
The duration of long afterglow and the intensity of afterglow under sunlight excitation of existing long afterglow polymer materials need to be further improved.
Tris(4-boronic acid pinene ester phenyl)amine was used as the fluorescent molecule and aromatic polyester was used as the matrix to form an electron donor/acceptor excitosome complex. Long afterglow polymer materials were prepared by heating, mixing and cooling.
It achieves a long afterglow effect of up to 12 hours, with enhanced afterglow intensity under sunlight excitation. The material possesses flexibility and transparency, making it suitable for flexible displays, anti-counterfeiting, information storage, and wearable smart devices.
Smart Images
Figure CN119752125B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of luminescent polymer technology. More specifically, it relates to a long-afterglow polymer material, its preparation method, and its applications. Background Technology
[0002] Long-afterglow polymer materials, as an emerging type of photoluminescent material, have attracted much attention in recent years due to their unique luminescent properties. When excited by a light source, these materials not only emit visible light but also effectively store some light energy. Once the excitation light source is turned off, they can slowly release the stored energy in the form of light, thus achieving a continuous luminescence effect ranging from seconds to hours. Long-afterglow materials show great potential in many fields requiring continuous illumination, such as information security, bioimaging, and night vision systems. Furthermore, their ability to emit light without an external power source also makes them candidate materials for energy-saving devices.
[0003] However, long-afterglow polymer materials also face a major challenge that urgently needs to be addressed: under environmental conditions, triplet excitons undergo rapid nonradiative decay, thus affecting the persistence of luminescence. To overcome this problem, researchers have actively explored and adopted various strategies to optimize afterglow properties, including introducing heavy atoms, designing specific molecular structures, employing doping techniques, utilizing self-assembly processes, and achieving controlled crystallization. Among these, Zhou et al. successfully obtained a polymer film with hour-long afterglow (HLA), which can sustain an afterglow time of up to 11 hours under ultraviolet light irradiation. Under 5 minutes of sunlight excitation, the afterglow intensity of this film can be increased by 74 times, a performance currently among the best known organic afterglow materials. However, despite these achievements, the duration of the long-life afterglow and the intensity of the afterglow under sunlight excitation still need further improvement to achieve even better results. Summary of the Invention
[0004] The technical problem to be solved by the present invention is to overcome the defects and shortcomings of existing long-afterglow polymer materials, such as the duration of long afterglow and the need to further improve the afterglow intensity under sunlight excitation. The present invention provides a long-afterglow polymer material that can achieve a long afterglow effect of up to 12 hours and has an ultra-long lifespan.
[0005] Another object of the present invention is to provide a method for preparing the above-mentioned long afterglow polymer material.
[0006] Another object of the present invention is to provide the application of the above-mentioned long afterglow polymer material in flexible displays, anti-counterfeiting, information storage or wearable smart devices.
[0007] The above-mentioned objective of this invention is achieved through the following technical solution:
[0008] This invention protects a long-afterglow polymer material, which is prepared using tris(4-borate pinene phenyl)amine (TTB) as the fluorescent molecule and an aromatic polyester as the matrix.
[0009] This application innovatively employs aromatic polyester as the polymer matrix, which not only possesses strong electron-withdrawing capabilities but also exhibits excellent oxygen-barrier properties, thus preventing the long afterglow from being quenched by oxygen. Simultaneously, tris(4-boronic acid pinene ester phenyl)amine, rich in electrons and capable of forming strong interactions with aromatic polyester, is selected as the fluorescent molecule and introduced into the system as both a chromophore dopant and an electron donor. During excitation, the electron donor interacts with the acceptor to form an electron donor / acceptor excitosome complex, which further dissociates into anionic and cationic free radicals. These free radicals migrate randomly within the polymer chain, and when free radicals carrying opposite charges recombine to form excitons (a bound state system in insulators or semiconductors where electrons and holes are bound together by Coulomb interactions), an ultra-long afterglow is released. This mechanism ensures that the material continuously emits a bright and persistent afterglow after excitation.
[0010] Furthermore, the aromatic polyester includes one or more of polyethylene terephthalate (PET), polypropylene terephthalate, and polybutylene terephthalate. These substances all have good electron-withdrawing and oxygen-blocking capabilities and can form a strong interaction with tris(4-boronic acid pinene phenyl)amine.
[0011] Furthermore, the mass ratio of the tris(4-boronic acid pinene ester phenyl)amine to the aromatic polyester is 100:(0.05-3). Within this mass ratio range, the polymer material formed by the mixture of the two exhibits good afterglow strength.
[0012] Furthermore, the mass ratio of the tris(4-boronic acid pinene ester phenyl)amine to the aromatic polyester is 100:(0.08-2).
[0013] Preferably, the mass ratio of tris(4-boronic acid pinene ester phenyl)amine to aromatic polyester is 100:(0.1-1).
[0014] More preferably, the mass ratio of tris(4-boronic acid pinene ester phenyl)amine to aromatic polyester is 100:(0.4 to 0.6). Within this mass ratio range, the polymer material formed by mixing the two has better afterglow strength.
[0015] This invention protects a method for preparing the above-mentioned long afterglow polymer material, comprising the following steps:
[0016] Tris(4-boronic acid pinene ester phenyl)amine and aromatic polyester are heated to melt and mixed, then cooled to obtain a long afterglow polymer material.
[0017] The preparation process of this long afterglow polymer material is simple and cost-effective, and it is expected to be applied in fields such as flexible displays, anti-counterfeiting, information storage, and wearable smart devices.
[0018] Furthermore, the heating temperature is 260–280°C.
[0019] Furthermore, the heating time is 5 to 10 minutes.
[0020] Furthermore, the mixing is agitation.
[0021] Furthermore, the mixing time is 1 to 3 minutes.
[0022] Furthermore, the cooling is cooling to room temperature.
[0023] This invention protects the application of the above-mentioned long afterglow polymer material in the fields of flexible display, anti-counterfeiting, information storage or wearable smart devices.
[0024] Compared with the prior art, the present invention has the following beneficial effects:
[0025] This application successfully prepared a long-afterglow polymer material by using tris(4-borate pineneol ester phenyl)amine as the luminescent center and electron donor, and a strongly electron-accepting aromatic polyester as the polymer matrix. The interaction between the electron-rich tris(4-borate pineneol ester phenyl)amine and the strongly electron-withdrawing aromatic polyester effectively slows down the nonradiative exciton transition process, thus achieving a long afterglow effect of up to 12 hours. Specifically, when this long-afterglow polymer material is excited by sunlight, the afterglow intensity is significantly enhanced, and it can maintain a green afterglow for up to 6 hours. Simultaneously, the material also exhibits excellent flexibility and transparency. Furthermore, the preparation process of this material is simple, and it holds promise for applications in flexible displays, anti-counterfeiting, information storage, and wearable smart devices. Attached Figure Description
[0026] Figure 1 The images show the afterglow spectra of the long afterglow polymer materials in Examples 1-3 after irradiation with a 365nm ultraviolet light source for 60 seconds and a delay of 1 hour.
[0027] Figure 2 The graph shows the transient fluorescence (515nm) decay curves of the long-afterglow polymer material in Example 1 under different durations of 365nm ultraviolet irradiation.
[0028] Figure 3The graph shows the functional relationship between the afterglow duration of the long afterglow polymer material in Example 1 and the duration of ultraviolet irradiation.
[0029] Figure 4 The image shows the UV-Vis spectra of the long afterglow polymer material in Example 1 before and after irradiation with 365nm ultraviolet light.
[0030] Figure 5 The image shows the electron spin resonance spectra of the long afterglow polymer material in Example 1 before and after irradiation with 365nm ultraviolet light.
[0031] Figure 6 The image shows the afterglow intensity of the long afterglow polymer material in Example 1 under different ultraviolet light source excitation wavelengths.
[0032] Figure 7 The image shows the two-dimensional phosphorescence spectra of the long afterglow polymer material in Example 1 under different ultraviolet light source excitation wavelengths.
[0033] Figure 8 The image shows the excitation wavelength-dependent phosphorescence spectrum of the long afterglow polymer material in Example 1.
[0034] Figure 9 The images show the fluorescence spectra of the long afterglow polymer material in Example 1 under different ultraviolet light source excitation wavelengths.
[0035] Figure 10 The images show the afterglow spectra of the long afterglow polymer material in Example 1 at different delay times.
[0036] Figure 11 The image shows the afterglow intensity spectrum of the long afterglow polymer material in Example 1 under 5 minutes of sunlight activation.
[0037] Figure 12 The diagram shows the afterglow duration of the long-afterglow polymer material in Example 1 under 5 minutes of sunlight activation.
[0038] Figure 13 This is a digital time statistics chart of the polymer film prepared based on the long afterglow polymer material in Example 1 after UV irradiation has stopped. Detailed Implementation
[0039] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the embodiments do not limit the present invention in any way. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in this technical field.
[0040] Unless otherwise specified, all reagents and materials used in the following examples are commercially available.
[0041] Example 1: Preparation of a long afterglow polymer material
[0042] Polyethylene terephthalate and tris(4-boronic acid pinene phenyl)amine were heated at 270°C for 8 minutes to reach a molten state in a mass ratio of 100:0.5. The mixture was then stirred for 2 minutes to ensure homogeneity. After cooling to room temperature, a long afterglow polymer material was obtained.
[0043] Example 2: Preparation of a long afterglow polymer material
[0044] The difference from Example 1 is that the mass ratio of polyethylene terephthalate to tris(4-boronic acid pinene phenyl)amine is changed from 100:0.5 to 100:0.1.
[0045] The other steps and conditions are the same as in Example 1.
[0046] Example 3: Preparation of a long afterglow polymer material
[0047] The difference from Example 1 is that the mass ratio of polyethylene terephthalate to tris(4-boronic acid pinene phenyl)amine is changed from 100:0.5 to 100:1.
[0048] The other steps and conditions are the same as in Example 1.
[0049] Experimental Example 1: Physical and Chemical Properties Testing of Long Afterglow Polymer Materials
[0050] 1. Determination of the effect of the mass ratio of tris(4-boronic acid pinene ester phenyl)amine in long-afterglow polymer materials on afterglow intensity
[0051] Depend on Figure 1 As can be seen, in Examples 1-3, the afterglow intensity of the long-afterglow polymer materials showed significant differences after 1 hour of 365nm ultraviolet irradiation. Specifically, with the initial increase of TTB content, the afterglow intensity of these materials tended to increase. This phenomenon is attributed to the increased concentration of luminescent centers, which promotes a more persistent and stable afterglow. However, as the TTB content continued to increase, the afterglow intensity gradually weakened. This is because excessively high TTB content accelerates the charge recombination rate, leading to a decrease in the concentration of excited states of the luminescent body, thereby shortening the duration of the afterglow.
[0052] 2. Afterglow intensity and afterglow lifetime tests of long-afterglow polymer materials under different excitation times of ultraviolet light source.
[0053] Depend on Figures 2-3It can be seen that the long-afterglow polymer material in Example 1 exhibits a trend of first increasing and then decreasing in afterglow lifetime and intensity after being irradiated by ultraviolet light for different durations (gradually increasing from 10s to 180s). Specifically, the material exhibits the best afterglow lifetime and intensity at an irradiation time of 60s. This phenomenon can be attributed to the charge-separated states within the material, which are generated by ultraviolet light excitation and serve as the source of afterglow. As the ultraviolet light irradiation time increases, the concentration of charge-separated states in the system gradually increases, thereby enhancing the afterglow lifetime and intensity. However, when the ultraviolet light irradiation time further increases, the charge recombination rate in the system also accelerates, leading to a decrease in the concentration of excited states of the luminescent body, which in turn causes a slight decrease in the afterglow lifetime and intensity.
[0054] 3. Measurement of UV-Vis spectra of long-afterglow polymer materials before and after UV excitation.
[0055] The long afterglow polymer material in Example 1 exhibits the following spectral characteristics after ultraviolet light irradiation: Figure 4 As shown, two distinct absorption peaks are observed, located at 582 nm and 701 nm, respectively. These two absorption peaks correspond to the characteristic absorptions of PET anionic radicals and TTB cationic radicals. This result strongly demonstrates that, under ultraviolet light excitation, a charge separation process of electron donor and acceptor successfully occurred between the fluorescent molecules and the aromatic polyester, thereby generating anionic and cationic radicals.
[0056] 4. Measurement of Electron Spin Resonance (ESR) Signal Changes in Long-Afterglow Polymer Materials Before and After Ultraviolet Excitation
[0057] In Example 1, the long-afterglow polymer material was irradiated with 365nm ultraviolet light, and its ESR was measured using a JEOL JES-FA200 instrument. The test results are as follows: Figure 5 As shown in the figure, a significant ESR signal is clearly displayed, indicating the generation of free radicals during irradiation. This result further confirms the generation of PET anion radicals and TTB cation radicals.
[0058] 5. Determination of the intensity, phosphorescence (RTP), and fluorescence (FL) spectra of hour-level afterglow (HLA) of long-afterglow polymer materials under different excitation wavelengths.
[0059] First, the long afterglow polymer material in Example 1, after being irradiated with excitation light of different wavelengths, undergoes... Figure 6It can be seen that within the wavelength range of 350–390 nm, the intensity of HLA gradually increases with increasing excitation wavelength; while within the range of 390–440 nm, the intensity of HLA gradually decreases with increasing excitation wavelength. This phenomenon indicates that the HLA of long-afterglow polymer materials has excitation wavelength responsive properties, and it can be effectively excited within a broad wavelength range of 350–440 nm, suggesting that it can also be excited by a portion of visible light (visible light wavelength range: 390–780 nm) to produce afterglow.
[0060] Secondly, the long afterglow polymer material in Example 1, after being irradiated by ultraviolet light sources of different wavelengths, undergoes... Figure 7 Similar to the intensity observation of HLA, the intensity of RTP gradually increases with increasing excitation wavelength in the range of 350–400 nm; however, in the range of 400–500 nm, the intensity of RTP gradually decreases with increasing excitation wavelength. This indicates that the RTP behavior of this material also depends on the excitation wavelength, covering a range of 350–500 nm. Notably, the emission spectrum of RTP exhibits a significant redshift with increasing excitation wavelength. Figure 8 This is attributed to the aggregation of chromophore molecules.
[0061] Finally, the long afterglow polymer material in Example 1, after being irradiated by excitation light sources of different wavelengths, undergoes... Figure 9 It can be seen that the maximum emission wavelength remains relatively stable, but the intensity of FL changes significantly with the excitation wavelength. Comparing FL and RTP, it is clear that RTP exhibits higher sensitivity to the excitation wavelength, affecting both its intensity and maximum emission wavelength, while the change in FL intensity is more significant. This difference stems from the different excited states produced by these two types of emission.
[0062] As can be seen from the above, long-afterglow polymer materials can emit three types of light simultaneously—long afterglow, fluorescence, and phosphorescence—under ultraviolet light excitation, which fully demonstrates their potential to adapt to different application needs.
[0063] 6. Duration of afterglow of long-afterglow polymer materials after excitation by ultraviolet light source
[0064] Depend on Figure 10 It can be seen that in the long-afterglow polymer material of Example 1, the afterglow intensity gradually weakens over time within 1 to 12 hours after the ultraviolet light source stops irradiating. It is noteworthy that even 12 hours after the ultraviolet light source stops irradiating, a significantly higher afterglow signal than the background value (bg) can still be detected at a wavelength of 515 nm. This fully demonstrates that the long-afterglow polymer material has a long afterglow characteristic of up to 12 hours after the ultraviolet light stops irradiating.
[0065] 7. Afterglow intensity and duration of long-afterglow polymer materials after sunlight excitation
[0066] Depend on Figure 11 It is evident that irradiating the long-afterglow polymer material in Example 1 under sunlight for 5 minutes significantly enhances the afterglow intensity, producing a clearly visible green afterglow. Compared to the intensity before irradiation, the afterglow intensity represents a 1257-fold increase. Furthermore, after sunlight irradiation ceases, the afterglow intensity gradually weakens over time (0.25–6 hours), but even 6 hours after irradiation ceases, an afterglow signal can still be detected at a wavelength of 530 nm. This fully demonstrates that the afterglow duration of this long-afterglow polymer material can reach up to 6 hours after sunlight irradiation ceases. Figure 12 ).
[0067] Experimental Example 2: Flexible Display Testing of Polymer Thin Films Based on Long Afterglow Polymer Materials
[0068] 1. Experimental Methods
[0069] PET powder was heated to 270°C until completely melted. Then, fluorescent molecules were rapidly added and thoroughly stirred to ensure uniform mixing. The mixture was then pressed into a polymer film with a thickness of 1 mm.
[0070] 2. Experimental Results
[0071] Depend on Figure 13 It is known that when the polymer film is irradiated with a 365nm wavelength ultraviolet light source for 1 minute, the film immediately emits nanosecond-level blue fluorescence corresponding to the preset pattern. Once the ultraviolet irradiation is stopped, the blue fluorescence quickly quenches and then transforms into millisecond- to second-level green phosphorescence, exhibiting a long afterglow effect. Subsequently, a bright green afterglow is clearly visible in the next 0–100 seconds. In the period from 100 to 3600 seconds, although the intensity of the afterglow gradually decreases, it still remains relatively bright. This polymer afterglow system, which can emit light continuously for several hours after only 1 minute of excitation, has potential application value in the field of high-efficiency flexible displays. In addition, the above-mentioned long-afterglow polymer material, with its unique luminescent properties, excellent long-afterglow effect, and outstanding flexibility and transparency, is also suitable for anti-counterfeiting, information storage, and wearable smart device fields.
[0072] In summary, this application successfully prepared a long-afterglow polymer material by employing a clever molecular doping strategy, using tris(4-borate pineneol ester phenyl)amine as the luminescent center and electron donor, and an aromatic polyester with strong electron-accepting ability as the polymer matrix. In this material, the interaction between the electron-rich tris(4-borate pineneol ester phenyl)amine and the strongly electron-withdrawing aromatic polyester effectively slows down the nonradiative transition process of excitons. Therefore, the long-afterglow polymer material prepared under optimal conditions exhibits a long afterglow effect of up to 12 hours under ultraviolet light irradiation. In particular, when this long-afterglow polymer material is excited by sunlight, the afterglow intensity is significantly enhanced, and it can maintain a green afterglow for up to 6 hours. Simultaneously, the material also exhibits excellent flexibility and transparency.
[0073] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.
Claims
1. A long afterglow polymer material, characterized in that, The long afterglow polymer material is prepared using tris(4-borate pinoxoyl phenyl)amine as the fluorescent molecule and an aromatic polyester as the matrix. The aromatic polyester includes one or more of polyethylene terephthalate, polypropylene terephthalate, and polybutylene terephthalate. The preparation method of the long afterglow polymer material includes the following steps: Tris(4-boronic acid pinoxoyl phenyl)amine and aromatic polyester are heated to melt and mixed, then cooled to obtain a long afterglow polymer material.
2. The long afterglow polymer material according to claim 1, characterized in that, The mass ratio of tris(4-boronic acid pinene ester phenyl)amine to aromatic polyester is 100:(0.05~3).
3. The long afterglow polymer material according to claim 2, characterized in that, The mass ratio of tris(4-boronic acid pinene ester phenyl)amine to aromatic polyester is 100:(0.08~2).
4. The long afterglow polymer material according to claim 3, characterized in that, The mass ratio of tris(4-boronic acid pinene ester phenyl)amine to aromatic polyester is 100:(0.1~1).
5. The long afterglow polymer material according to claim 4, characterized in that, The mass ratio of tris(4-boronic acid pinene ester phenyl)amine to aromatic polyester is 100:(0.4~0.6).
6. The long afterglow polymer material according to claim 1, characterized in that, The heating temperature is 260~280℃.
7. The long afterglow polymer material according to claim 1, characterized in that, The heating time is 5 to 10 minutes.
8. The application of the long afterglow polymer material according to any one of claims 1 to 7 in the fields of flexible display, anti-counterfeiting, information storage or wearable smart devices.