A cashew phenol-based fluorescent compound, its preparation method and uses, and fluorescent polyurethane materials prepared from it and their uses.
By introducing boron-containing structural units and reactive groups into the cashew phenol molecule, cashew phenol-based fluorescent compounds were prepared, solving the problem of the single function of existing fluorescent materials. This enabled multi-dimensional information regulation and the construction of polymer materials, which can be applied to the fields of information anti-counterfeiting and intelligent response materials.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- INST OF CHEM IND OF FOREST PROD CHINESE ACAD OF FORESTRY
- Filing Date
- 2026-04-03
- Publication Date
- 2026-06-30
AI Technical Summary
Existing fluorescent materials mostly rely on a single response mechanism, have relatively limited functions, and are difficult to achieve multidimensional information regulation. Furthermore, organic boron fluorescent molecules are difficult to participate in the construction of polymer materials.
By introducing boron-containing structural units into the cashew nut molecule to form a B←N coordination structure, cashew nut-based fluorescent compounds are prepared. These compounds are then combined with reactive hydroxyl and amino groups to participate in polyurethane reactions, thereby constructing a fluorescent responsive polymer material system.
The response behavior of fluorescent materials to various metal ions was realized, which can produce fluorescence changes under the action of metal ions and realize information writing, regulation or recovery through external stimulation, thus constructing a multi-dimensional information anti-counterfeiting system.
Smart Images
Figure CN122301923A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a cashew phenol-based fluorescent compound, its preparation method and uses, and fluorescent polyurethane materials prepared from it and their uses, belonging to the field of fluorescent functional materials technology. Background Technology
[0002] With the development of fluorescent functional materials, they have been widely used in fields such as information anti-counterfeiting, environmental monitoring, and ion response. Utilizing changes in fluorescence signals to visualize information provides an effective means for anti-counterfeiting and information encryption. However, existing fluorescent materials mostly rely on a single response mechanism, resulting in relatively limited functionality and making it difficult to achieve multidimensional information regulation.
[0003] Organoboron compounds have attracted attention in the field of fluorescent materials due to their unique electronic structure and coordination properties. Boron atoms can form coordination structures with nitrogen-containing groups, making them potentially applicable in areas such as ion responses. However, existing organoboron fluorescent molecules exhibit limited ion responses, restricting their applications. Furthermore, most existing organoboron fluorescent molecules possess non-reactive structures, making it difficult to further integrate them into the construction of polymer materials.
[0004] Cashew phenol is a natural phenolic compound derived from cashew nut shell liquid, possessing significant advantages such as abundant resources, low cost, renewability, and biodegradability. Its molecule contains multiple reactive sites, including phenolic hydroxyl groups and olefinically unsaturated long carbon chains, facilitating chemical modification and functional design. Previous studies have shown that cashew phenol can be used in polyurethanes and shape memory materials; however, combining it with boron-containing coordination structures to construct molecular systems exhibiting both fluorescence responsiveness and reactivity remains relatively rare.
[0005] Therefore, it is necessary to provide a boron-containing fluorescent compound based on the cashew phenol skeleton, which can not only have fluorescence response function, but also participate in the construction of polymer materials as a reactive unit, thereby expanding its application range. Summary of the Invention
[0006] This invention provides a cashew nut phenol-based fluorescent compound, its preparation method and uses, and fluorescent polyurethane materials prepared from it, addressing the problem that existing fluorescent molecules struggle to possess both fluorescence responsiveness and reactivity. The compound acquires fluorescence emission properties and exhibits fluorescence responsiveness to various metal ions by introducing boron-containing structural units into the cashew nut molecule and forming a B←N coordination structure. Furthermore, the compound contains reactive hydroxyl and / or amino groups, which can participate in polyurethane reactions as functional units to construct a fluorescent responsive polymer material system. Based on these characteristics, the material can produce fluorescence changes under the influence of metal ions, enabling information writing, and can regulate or recover information under external stimuli, thus serving as an anti-counterfeiting measure.
[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:
[0008] The structural formula of the cashew phenolic fluorescent compound is as follows:
[0009]
[0010] The value of n ranges from 0 to 3.
[0011] The cashew phenol-based fluorescent compound structure of this application includes a single boron structure or a dual-coordination structure.
[0012] The aforementioned cashew phenolic fluorescent compounds exhibit fluorescence emission of 368-372 nm under excitation light of 315-335 nm.
[0013] A method for preparing a cashew phenol-based fluorescent compound involves reacting cashew phenol glycidyl ether and a nitrogen-containing borate ester intermediate in a first organic solvent at 100–180 °C for 1–6 h, followed by cooling and purification to obtain the cashew phenol-based fluorescent compound.
[0014] To ensure the performance of the cashew phenol-based fluorescent compound and its downstream products, the preparation method of the above-mentioned nitrogen-containing borate ester intermediate is as follows: the nitrogen-containing compound and the borate compound are dissolved in a second organic solvent and reacted at 30-60 °C for 1-3 h to generate the nitrogen-containing borate ester intermediate; the nitrogen-containing compound is at least one of N,N-bis(2-hydroxyethyl)ethylenediamine and N,N,N',N'-tetra(2-hydroxyethyl)ethylenediamine; the borate compound is at least one of 3-aminophenylboronic acid and 1,4-phenylenediboronic acid; the molar ratio of the nitrogen-containing compound to the borate compound is (0.8-2.2):1.
[0015] The first and second organic solvents mentioned above can both be at least one of DMF (N,N-dimethylformamide), DMAc (N,N-dimethylacetamide), THF (tetrahydrofuran), or dioxane.
[0016] The preparation method of the above-mentioned cashew phenol glycidyl ether is as follows: cashew phenol and epichlorohydrin are used as raw materials, and reacted at 70~90 ℃ for 8~12 h in the presence of alkali and phase transfer catalyst to obtain cashew phenol glycidyl ether.
[0017] The aforementioned cashew phenolic fluorescent compounds exhibit fluorescence response behavior to a variety of metal ions.
[0018] The above-mentioned cashew phenolic fluorescent compounds can be used in Fe 3+ Fluorescence detection; and / or, for Cu 2+ Fluorescence detection; and / or, for Co 2+Fluorescence detection; and / or, through the synergistic effect of metal ion-induced fluorescence signal changes and the shape memory behavior of materials, for anti-counterfeiting or information encryption.
[0019] As one preferred embodiment, the structure of the above-mentioned cashew phenolic fluorescent compound is as follows:
[0020] This structure exhibits a corresponding fluorescence spectrum upon excitation with 325 nm excitation light, with an emission wavelength of 368 nm. For Fe... 3+ The detection limit is 0.49 μM for Co. 2+ The detection limit is 0.87 μM.
[0021] In preparing nitrogen-containing borate intermediates, the nitrogen-containing compound is N,N-bis(2-hydroxyethyl)ethylenediamine; the borate compound is 3-aminophenylboronic acid.
[0022] As another preferred embodiment, the structure of the above-mentioned cashew phenolic fluorescent compound is as follows:
[0023] This structure exhibits a corresponding fluorescence spectrum upon excitation with 335 nm light, with an emission wavelength of 372 nm. For Fe... 3+ The detection limit is 0.33 μM for Cu. 2+ The detection limit is 0.63 μM.
[0024] When preparing nitrogen-containing borate intermediates, the nitrogen-containing compound is N,N,N',N'-tetra(2-hydroxyethyl)ethylenediamine; the borate compound is 3-aminophenylboronic acid.
[0025] As another preferred embodiment, the structure of the above-mentioned cashew phenolic fluorescent compound is as follows:
[0026] This structure exhibits a corresponding fluorescence spectrum upon excitation with 315 nm light, with an emission wavelength of 369 nm. This structure is effective for Fe... 3+ Cu 2+ and Co 2 + It exhibits significant fluorescence quenching behavior, with quenching efficiencies reaching 99%, 90%, and 94%, respectively. This structure was applied to ion detection, specifically for Fe... 3+ The detection limit is 0.47 μM for Co. 2+ The detection limit is 0.87 μM for Cu. 2+ The detection limit is 0.93 μM.
[0027] In preparing nitrogen-containing borate intermediates, the nitrogen-containing compound is N,N-bis(2-hydroxyethyl)ethylenediamine; the borate compound is 1,4-phenylenediboronic acid.
[0028] The aforementioned cashew phenol-based fluorescent compounds can also be used as reactive fluorescent chain extenders. For example, they can be used as reactive fluorescent chain extenders in the preparation of polyurethanes.
[0029] A fluorescent polyurethane material is prepared by reacting dicyclohexylmethane diisocyanate, polycaprolactone diol, and the aforementioned cashew nut phenol-based fluorescent compound. The dicyclohexylmethane diisocyanate and polycaprolactone diol are reacted at 60-80 °C for 2-4 h, then the cashew nut phenol-based fluorescent compound is added, and the reaction continues at 60-80 °C for another 2-4 h. The mixture is then spread, dried, and a fluorescent polyurethane film is obtained. The mass ratio of dicyclohexylmethane diisocyanate, polycaprolactone diol, and the cashew nut phenol-based fluorescent compound is 1:1:(2-4). The fluorescent polyurethane material exhibits fluorescence emission of 538-545 nm under 365 nm ultraviolet light irradiation.
[0030] The aforementioned fluorescent polyurethane material is used to prepare triple anti-counterfeiting materials, and the triple anti-counterfeiting method is as follows:
[0031] 1) Utilize Fe 3+ The solution imprints a pattern on a fluorescent polyurethane film. The pattern is invisible under natural light but can be observed under 405 nm ultraviolet light irradiation, containing Fe. 3+ The fluorescence in the corresponding position is quenched, while other positions emit normal light, achieving a layer of anti-counterfeiting with dark patterns and bright backgrounds;
[0032] 2) Fold the fluorescent polyurethane film obtained in step 1) into a preset temporary shape (such as a windmill shape or other folded / rolled structure), keep it for 24 hours, and the fluorescent polyurethane film will naturally remain in the temporary shape without external force. Then, after heating at a temperature of 37~40 ℃ for 10~15 s, the fluorescent polyurethane film will automatically recover to a flat shape without crease marks. At the same time, the engraved pattern will be displayed under 405 nm ultraviolet light irradiation, realizing double anti-counterfeiting.
[0033] 3) After immersing the fluorescent polyurethane film obtained in step 2) in a 2±0.2 mmol / L disodium ethylenediaminetetraacetate solution for 18~24 days, the fluorescence in step 1) will be quenched and disappear, and no pattern will be displayed, thus achieving triple anti-counterfeiting by erasing information.
[0034] The aforementioned fluorescent polyurethane film generates localized fluorescence changes under the action of metal ions to write information, and erases or restores the information under external stimuli, realizing multiple anti-counterfeiting measures using the same material, improving security, and is simple and economical.
[0035] This application uses cashew nut shell extract as a backbone and introduces organic boron units to construct a B←N coordination structure in the molecule, thereby endowing the compound with fluorescence properties and the ability to recognize and respond to various metal ions. Furthermore, the compound molecule contains reactive hydroxyl and / or amino groups, which can participate in polyurethane reactions as reactive functional units to prepare fluorescent polyurethane materials with multi-stimulus responsive properties. The material can produce localized fluorescence changes under the action of metal ions, realizing information writing, and can be erased or restored by external stimuli. Simultaneously, combined with shape memory effects, it achieves reversible control of information, thereby constructing a multi-dimensional information anti-counterfeiting system. The raw materials of this invention are widely available, the preparation method is simple, and it has good application prospects in the field of information anti-counterfeiting and intelligent response materials.
[0036] Any techniques not mentioned in this invention are based on existing technologies.
[0037] The cashew phenol-based fluorescent compound of the present invention, its preparation method and uses, and the fluorescent polyurethane materials prepared therefrom and their uses, have the following beneficial effects:
[0038] 1) This invention uses cashew phenol as the molecular backbone, introduces boron-containing structural units, and constructs a B←N coordination structure in the molecule, giving the resulting compound fluorescence emission properties and the ability to react with Fe. 3+ Cu 2+ and Co 2+ Multiple metal ions can generate fluorescence responses, thus expanding their application in fluorescent functional materials;
[0039] 2) The compound contains hydroxyl and / or amino groups, which are reactive and can participate in polyurethane reactions as functional units, realizing the functional extension from small molecules to polymer materials, which is beneficial for constructing functionalized polymer systems.
[0040] 3) The fluorescent polyurethane material prepared based on the above compounds can produce fluorescence changes under the action of metal ions, realize information writing, and can realize information regulation or recovery under the action of external stimuli, thereby constructing information anti-counterfeiting function;
[0041] 4) This invention constructs a functional material system that integrates fluorescence response, metal ion response and shape memory regulation, which is conducive to realizing multi-dimensional information expression and expands the application of fluorescent materials in the field of information anti-counterfeiting.
[0042] 5) The compound described in this invention uses cashew phenol from natural sources as raw material, has a tunable structure, a simple preparation process, and good application prospects. Attached Figure Description
[0043] Figure 1The images show the infrared spectra and specific structures of the cashew phenolic fluorescent compounds obtained in Examples 1-3. Specifically, (a) shows the cashew phenolic fluorescent compound obtained in Example 1, (b) shows the cashew phenolic fluorescent compound obtained in Example 2, and (c) shows the cashew phenolic fluorescent compound obtained in Example 3.
[0044] Figure 2 The fluorescence emission spectra of the compounds obtained in Examples 1-3 are shown in the presence of different metal ions. Among them, (a) is the cashew phenolic fluorescent compound obtained in Example 1, (b) is the cashew phenolic fluorescent compound obtained in Example 2, and (c) is the cashew phenolic fluorescent compound obtained in Example 3; Blank represents the control sample without the addition of metal ions.
[0045] Figure 3 The images show the cashew nut phenol-based fluorescent polyurethane materials obtained in Examples 1-3 under 365nm irradiation. Among them, (a) is the cashew nut phenol-based fluorescent polyurethane obtained in Example 1, (b) is the cashew nut phenol-based fluorescent polyurethane obtained in Example 2, and (c) is the cashew nut phenol-based fluorescent polyurethane obtained in Example 3.
[0046] Figure 4 This is a schematic diagram illustrating the anti-counterfeiting application of the cashew phenol-based fluorescent shape memory polyurethane material in Embodiment 4 of the present invention. Detailed Implementation
[0047] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.
[0048] Unless otherwise specified, all examples were conducted at room temperature (15~25℃). Unless otherwise specified, all examples were conducted at 200 r / min.
[0049] Example 1
[0050] (1) Preparation of cashew phenol glycidyl ether:
[0051] Six g of cashew nut shellac was added to a four-necked round-bottom flask equipped with a mechanical stirrer, thermometer, and reflux condenser. 14.8 g of epichlorohydrin, 0.46 g of benzyltriethylammonium chloride, and 0.8 g of sodium hydroxide were added sequentially, and the mixture was stirred at 70 °C for 11 h. After the reaction was complete, the reaction system was washed with deionized water until neutral, dried over anhydrous magnesium sulfate, filtered, and the solvent was removed under reduced pressure to obtain cashew nut shellac glycidyl ether (CGE).
[0052] (2) Preparation of nitrogen-containing borate intermediates
[0053] In a reactor equipped with a stirrer and a reflux condenser, 7.78 g of N,N-bis(2-hydroxyethyl)ethylenediamine, 6.85 g of 3-aminophenylboronic acid, and 50 mL of DMF were added, and the mixture was stirred at 40 °C for 1 h to obtain a nitrogen-containing borate ester intermediate.
[0054] (3) Preparation of the target fluorescent compound
[0055] In a reactor equipped with a stirrer and a reflux condenser, 0.71 g of CGE, 0.25 g of the nitrogen-containing borate ester intermediate prepared in this example, and 40 mL of DMF were added, and the mixture was stirred at 140 °C for 1 h. After the reaction was completed, the mixture was cooled, the solvent was removed under reduced pressure, and the product was washed three times with n-hexane. Finally, it was rotary evaporated to obtain the target compound: a cashew phenolic fluorescent compound. Its infrared spectrum and specific structure are shown in [reference needed]. Figure 1 .
[0056] Fluorescence properties of the obtained target compound were tested: Al was prepared at a concentration of 0.01 mol / L in DMF. 3+ Ca 2+ Co 2+ K + Cu 2+ Fe 3+ Solutions of various metal ions were prepared. Then, 100 mg of the cashew phenol-based fluorescent compound and 0.5 ml of solutions of various metal ions were placed in a 10 ml volumetric flask, and DMF was added to dilute to a concentration of 10 mg / ml for the cashew phenol-based fluorescent compound. The corresponding fluorescence spectra were obtained by excitation with 325 nm light on a fluorescence spectrometer, with a corresponding emission wavelength of 368 nm. Among these, in Fe... 3+ or Co 2+ In its presence, its fluorescence intensity is significantly reduced, affecting Fe. 3+ or Co 2+ The fluorescence quenching efficiencies reached 98% and 65%, respectively. (Based on the detection limit formula...) (Where, LOD is the limit of detection, σ is the standard deviation of the signal from multiple parallel determinations of the blank sample, and K is the slope of the standard curve), the effect of cashew phenolic fluorescent compounds on Fe 3+ and Co 2+ The detection limits are 0.49 μM and 0.87 μM.
[0057] (4) Preparation of fluorescent polyurethane materials
[0058] In a reactor equipped with a stirrer, 0.66 g of dicyclohexylmethane diisocyanate and 1 g of polycaprolactone diol (Mn=2000, Shanghai Aladdin Reagent Co., Ltd.) were added, and the mixture was stirred at 80 °C for 4 h to obtain a prepolymer. Subsequently, 0.48 g of the cashew nut phenol-based fluorescent compound prepared in this example was added, and the reaction was continued for 4 h under the same conditions (stirring at 80 °C). After the reaction was complete, the system was poured into a mold and dried at 80 °C for 12 h to obtain a fluorescent polyurethane film with a thickness of 0.25 mm. The film exhibited fluorescence emission of approximately 540 nm under 365 nm ultraviolet light irradiation (see...). Figure 3 ).
[0059] Example 2
[0060] CGE was prepared according to the method in Example 1.
[0061] In a reactor equipped with a stirrer and a reflux condenser, 6.20 g of N,N,N',N'-tetra(2-hydroxyethyl)ethylenediamine, 6.85 g of 3-aminophenylboronic acid and 50 mL of THF were added, and the mixture was reacted at 50 °C for 1 h to obtain a nitrogen-containing borate ester intermediate.
[0062] In a reactor equipped with a stirrer and a reflux condenser, 0.71 g of CGE, 0.44 g of the nitrogen-containing borate ester intermediate prepared in this example, and 40 mL of DMF were added. The reaction was carried out at 160 °C for 2 h. After the reaction was completed, the mixture was cooled, the solvent was removed under reduced pressure, and the mixture was washed three times with n-hexane. Finally, it was rotary evaporated to obtain the target compound: cashew phenolic fluorescent compound. The infrared spectrum and specific structure are shown in [reference needed]. Figure 1 .
[0063] The fluorescence properties of the obtained target compounds were tested, following the method described in Example 1: fluorescence spectra were obtained by excitation with 335 nm excitation light on a fluorescence spectrometer, with corresponding emission wavelengths of 372 nm. Specifically, in Fe... 3+ or Cu 2 + In its presence, its fluorescence intensity is significantly reduced, affecting Fe. 3+ or Cu 2+ The fluorescence quenching efficiencies reached 99% and 61%, respectively, with a significant decrease in fluorescence intensity and a fluorescence quenching efficiency of 99%. (Based on the detection limit formula...) The effect of cashew phenolic fluorescent compounds on Fe was calculated. 3+ or Cu 2+ The detection limits are 0.33 μM and 0.63 μM.
[0064] In a four-necked flask equipped with a stirrer, 0.56 g of isophorone diisocyanate and 1 g of polycaprolactone diol (Mn=2000, Shanghai Aladdin Reagent Co., Ltd.) were added, and the mixture was stirred at 80 °C for 4 h to obtain a prepolymer. Then, 0.58 g of the cashew nut shell fluorescent compound prepared in this example was added, and the reaction was continued for 4 h under the same conditions (stirring at 80 °C). After the reaction was complete, the system was poured into a mold and dried at 80 °C for 12 h to obtain a fluorescent polyurethane film with a thickness of 0.25 mm. The film exhibited fluorescence emission of approximately 543 nm under 365 nm ultraviolet light irradiation (see...). Figure 3 ).
[0065] Example 3
[0066] CGE was prepared according to the method in Example 1.
[0067] In a reactor equipped with a stirrer and a reflux condenser, 7.78 g of N,N-bis(2-hydroxyethyl)ethylenediamine, 4.14 g of 1,4-phenylenediboric acid and 50 mL of DMF were added, and the mixture was stirred at 50 °C for 1 h to obtain a nitrogen-containing borate intermediate.
[0068] In a reactor equipped with a stirrer and a reflux condenser, 0.71 g of CGE, 0.39 g of the nitrogen-containing borate ester intermediate prepared in this example, and 40 mL of DMF were added. The mixture was stirred at 180 °C for 2 h. After the reaction was completed, the mixture was cooled, the solvent was removed under reduced pressure, and the product was washed three times with n-hexane. Finally, it was rotary evaporated to obtain the target compound: cashew phenolic fluorescent compound. The infrared spectrum and specific structure are shown in [reference needed]. Figure 1 .
[0069] The fluorescence properties of the obtained target compounds were tested: the testing method was the same as in Example 1. The corresponding fluorescence spectra were obtained by excitation with 315 nm excitation light on a fluorescence spectrometer, with a corresponding emission wavelength of 369 nm. Among them, in Fe... 3+ Cu 2+ and Co 2+ Its fluorescence intensity is significantly reduced in the presence of metal ions, particularly for Fe. 3+ Cu 2+ and Co 2+ It exhibits obvious fluorescence quenching behavior, with quenching efficiencies reaching 99%, 90%, and 94%, respectively. According to the detection limit formula... The effect of cashew phenolic fluorescent compounds on Fe was calculated. 3+ Co 2+ and Cu 2+ The detection limits are 0.47 μM, 1.25 μM and 0.93 μM.
[0070] In a four-necked flask equipped with a stirrer, 0.56 g of dicyclohexylmethane 4,4-diisocyanate and 1 g of polycaprolactone diol (Mn=2000, Shanghai Aladdin Reagent Co., Ltd.) were added, and the mixture was stirred at 80 °C for 4 h to obtain a prepolymer. Then, 0.55 g of the cashew phenol-based fluorescent compound prepared in this example was added, and the reaction was continued for 4 h under the same conditions (stirring at 80 °C). After the reaction was complete, the system was poured into a mold and dried at 80 °C for 12 h to obtain a fluorescent polyurethane film with a thickness of 0.25 mm. The film exhibited fluorescence emission of approximately 542 nm under 365 nm ultraviolet light irradiation (see...). Figure 3 ).
[0071] Example 4
[0072] Based on the metal ion response characteristics and shape memory properties of the aforementioned polyurethane material, an information anti-counterfeiting application is constructed:
[0073] Immersed with 1 mmol / L Fe 3+ The filter paper stamp of the solution (patterned as "N", "J", "F", "U") was placed on the surface of the polyurethane film (obtained in Example 1) for about 5 minutes. After removing the stamp, the pattern was not visible under natural light, and under 405 nm ultraviolet light irradiation, it did not contact Fe. 3+ The area exhibits uniform and bright fluorescence emission, while the area in contact with the stamp shows Fe... 3+ The quenching effect causes the luminescence to disappear, creating a contrast between a dark pattern and a bright background, thus enabling information writing. Subsequently, the film is deformed, folded into a windmill shape, and held for 24 hours to maintain a temporary shape for further information concealment. Under heating at 37°C, the film recovers to its initial shape after 15 seconds, and under 405nm ultraviolet light irradiation, the original dark patterns "N", "J", "F", and "U" clearly reappear, restoring the information. Furthermore, after immersing the film in a 2 mmol / L Na₂EDTA solution for 24 hours, Fe… 3+ Once the complexation is removed and the quenching effect disappears, the thin film returns to a uniform luminescent state, and the original pattern completely disappears, thus erasing the information. Through the above process, the material can achieve information writing, control, and erasure based on metal ion response and shape memory behavior.
Claims
1. A cashew phenolic fluorescent compound, characterized in that, Its structural formula is as follows: ； The value of n ranges from 0 to 3.
2. The cashew phenolic fluorescent compound according to claim 1, characterized in that, It exhibits fluorescence emission at 368–372 nm under excitation light of 315–335 nm.
3. A method for preparing the cashew phenolic fluorescent compound according to claim 1 or 2, characterized in that, Cashew phenol glycidyl ether and a nitrogen-containing borate ester intermediate were reacted in a first organic solvent at 100–180 °C for 1–6 h for ring-opening reaction. After cooling and purification, cashew phenol-based fluorescent compounds were obtained. The first organic solvent was at least one of DMF, DMAc, THF or dioxane.
4. The method for preparing the cashew phenolic fluorescent compound according to claim 3, characterized in that, The preparation method of the nitrogen-containing borate ester intermediate is as follows: a nitrogen-containing compound and a borate compound are dissolved in a second organic solvent and reacted at 30-60 °C for 1-3 h to generate the nitrogen-containing borate ester intermediate; the nitrogen-containing compound is at least one of N,N-bis(2-hydroxyethyl)ethylenediamine and N,N,N',N'-tetra(2-hydroxyethyl)ethylenediamine; the borate compound is at least one of 3-aminophenylboronic acid and 1,4-phenyldiboronic acid; the molar ratio of the nitrogen-containing compound to the borate compound is (0.8-2.2):
1.
5. The method for preparing the cashew phenolic fluorescent compound according to claim 4, characterized in that, The second organic solvent is at least one of DMF, DMAc, THF, or dioxane.
6. The use of the cashew phenolic fluorescent compound according to claim 1, characterized in that, For Fe 3+ Fluorescence detection; and / or, for Cu 2+ Fluorescence detection; and / or, for Co 2+ Fluorescence detection; and / or, through the synergistic effect of metal ion-induced fluorescence signal changes and the shape memory behavior of materials, for anti-counterfeiting or information encryption.
7. The use of the cashew phenolic fluorescent compound according to claim 1, characterized in that, As a reactive fluorescent chain extender.
8. The use according to claim 7, characterized in that, It is used as a reactive fluorescent chain extender in the preparation of polyurethane.
9. A fluorescent polyurethane material, characterized in that, The fluorescent polyurethane material is prepared by reacting dicyclohexylmethane diisocyanate, polycaprolactone diol, and the cashew nut phenol-based fluorescent compound as described in claim 1 or 2. Specifically, dicyclohexylmethane diisocyanate and polycaprolactone diol are reacted at 60-80 °C for 2-4 h, then the cashew nut phenol-based fluorescent compound is added, and the reaction is continued at 60-80 °C for another 2-4 h. After film deposition and drying, a fluorescent polyurethane material is obtained. The mass ratio of dicyclohexylmethane diisocyanate, polycaprolactone diol, and cashew nut phenol-based fluorescent compound is 1:1:2-4. The fluorescent polyurethane material exhibits fluorescence emission of 538-545 nm under 365 nm ultraviolet light irradiation.
10. The use of the fluorescent polyurethane material according to claim 9, characterized in that, For triple anti-counterfeiting, the triple anti-counterfeiting methods are as follows: 1) Utilize Fe 3+ The solution imprints a pattern on a fluorescent polyurethane film. The pattern is invisible under natural light but can be observed under 405 nm ultraviolet light irradiation, containing Fe. 3+ The fluorescence in the corresponding position is quenched, while other positions emit normal light, achieving a layer of anti-counterfeiting with dark patterns and bright backgrounds; 2) Fold the fluorescent polyurethane film obtained in step 1) into a preset temporary shape and keep it for 24 hours. Without external force, the fluorescent polyurethane film will naturally remain in the temporary shape. Then, after heating at a temperature of 37~40 ℃ for 10~15 s, the fluorescent polyurethane film will automatically recover to a flat shape without creases. At the same time, the engraved pattern will be displayed under 405 nm ultraviolet light, achieving double anti-counterfeiting. 3) After immersing the fluorescent polyurethane film obtained in step 2) in a 2±0.2 mmol / L disodium ethylenediaminetetraacetate solution for 18~24 days, the fluorescence in step 1) will be quenched and disappear, and no pattern will be displayed, thus achieving triple anti-counterfeiting by erasing information.