Responsive room temperature phosphorescent polymer material, preparation method and application thereof

Abstract

The application provides a novel organic room-temperature phosphorescent high molecular material shown in formula I, which takes natural high molecular polysaccharide as raw material, promotes intersystem crossing by introducing aromatic carboxylic acid salt groups, and enhances the interaction between molecular chains. The obtained phosphorescent high molecular material has excellent processability and pH response, and can be made into phosphorescent thin films, phosphorescent coatings and phosphorescent ink phosphorescent coatings, and has important application prospects in the fields of anti-counterfeiting and encryption.

Description

Technical Field

[0001] This invention relates to an organic room-temperature phosphorescent polymer material, its preparation method, and its application, belonging to the technical fields of organic optical materials and functional polymer materials. Background Technology

[0002] Organic room-temperature phosphorescent materials are gaining increasing attention in fields such as information encryption, anti-counterfeiting, bioimaging, and optical sensing due to their high signal-to-noise ratio, long luminescence lifetime, and absence of background fluorescence and scattered light interference. However, the lack of effective intersystem crossing or strong nonradiative transitions in most organic materials makes the preparation of organic room-temperature phosphorescent materials extremely challenging.

[0003] Stimulus-responsive phosphorescent materials can reflect changes in the environment, providing richer information such as alterations in external environmental factors like heat, light, force, pH, and O2. pH changes are closely related to many biochemical processes, chemical reactions, and the ecological environment. Furthermore, pH-responsive materials are highly suitable for advanced anti-counterfeiting and information encryption because the pH response process is highly concealed, resistant to interference, and easy to implement. Therefore, the development of pH-responsive optical materials is extremely important. Currently, the types of pH-responsive phosphorescent materials are still limited, and they suffer from problems such as complex preparation, insignificant responsiveness (phosphorescence response is only possible at low temperatures, such as 77K, and the phosphorescence lifetime is short, typically in the microsecond or millisecond range), and poor formability (they cannot be used to prepare inks, coatings, or films, and the molding and processing methods are limited). Summary of the Invention

[0004] This invention uses natural high-molecular-weight polysaccharides as raw materials and introduces aromatic carboxylate groups to promote intersystem crossing and enhance intermolecular interactions, resulting in a novel organic room-temperature phosphorescent polymer material. The obtained phosphorescent polymer material exhibits excellent processability and pH responsiveness, and can be formulated into phosphorescent films, phosphorescent coatings, and phosphorescent inks. It shows significant application potential in fields such as anti-counterfeiting and encryption.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] An organic room-temperature phosphorescent polymer material having the structure shown in Formula I:

[0007]

[0008] in:

[0009] A1, A2, and A3 may be the same or different, and are independently selected from H, -C(=O)-CH3, or aromatic carboxylate group R2; Y is selected from O or NH;

[0010] The aromatic carboxylate group R2 is selected from at least one of the following structures:

[0011]

[0012]

[0013] This is the connection point;

[0014] Cation M For: Na + Li + K + 、Rb + Cs + NH4 + C(NH2)3 + At least one of them;

[0015] Group X is: H, F, Cl, Br, I, NO2, C≡CH, CH=CH2, COOM -NH-C(=O)-CH3,OH,-C(=O)-C≡C-Ph,C 1-6 At least one of the alkyl groups;

[0016] The main chain is a polysaccharide, and the degree of polymerization (DP) of the polysaccharide is an integer between 50 and 5000.

[0017] According to an embodiment of the present invention, the backbone of the organic room-temperature phosphorescent polymer material is a natural polysaccharide.

[0018] According to an embodiment of the present invention, the natural polysaccharide is at least one selected from cellulose, starch, chitosan, and chitin.

[0019] According to an embodiment of the present invention, the degree of polymerization DP is an integer from 100 to 4000, such as 220, 400, 500, 600, 650 or 800.

[0020] According to an embodiment of the present invention, the degree of substitution of the aromatic carboxylate group R2 in the polysaccharide is 0.2-2.0, for example 0.5-1.5, such as 0.51, 0.61, 0.82, 1.2, 0.95 or 1.42.

[0021] This invention also provides a method for preparing the organic room-temperature phosphorescent polymer material as described above, comprising the following steps:

[0022] The polysaccharide is dissolved in a solvent to obtain a polysaccharide solution; an acylation reagent is added to the obtained polysaccharide solution to carry out the reaction and obtain a polysaccharide ester; the polysaccharide ester is mixed and stirred with an aqueous solution of carbonate or bicarbonate.

[0023] The acylation reagent is selected from acid anhydrides, acyl chlorides, or carboxylic acids containing the aromatic carboxylic acid group R2 after removing the M.

[0024] The solvent is selected from ionic liquids.

[0025] In one embodiment, the method further includes the steps of filtering after stirring, dialyzing the filtrate with water, and drying to obtain an organic room temperature phosphorescent polymer material.

[0026] In one embodiment, the molar ratio of the polysaccharide to the acylation reagent is 10:1 to 1:10.

[0027] In one implementation, the reaction temperature is room temperature.

[0028] In one embodiment, the polysaccharide is selected from at least one of cellulose, starch, chitosan, and chitin;

[0029] In one embodiment, the acylation agent is selected from at least one of the following anhydrides, either unsubstituted or optionally substituted with one, two, or more groups X: phthalic anhydride, trimellitic anhydride, 2,3-anthracite anhydride, 1,8-naphthalenedicarboxylic anhydride, perylene-3,4-dicarboxylic anhydride, 2,2'-biphenyl anhydride, phenylmaleic anhydride, 2-sulfobenzoic anhydride, 2,3-pyridinedicarboxylic anhydride, 2,3-thiophenedicarboxylic anhydride, and 3,4-thiophenedicarboxylic anhydride; wherein the group X is selected from at least one of the following groups: F, Cl, Br, I, NO2, alkynyl, CH=CH2, COOM. , -NH-C(=O)-CH3,OH, -C(=O)-C≡C-Ph,C 1-6 alkyl;

[0030] In one embodiment, the solvent is selected from at least one of the following: 1-ethyl-3-methylimidazolium chloride ionic liquid, 1-ethyl-3-methylimidazolium bromide ionic liquid, 1-allyl-3-methylimidazolium chloride ionic liquid, 1-allyl-3-methylimidazolium bromide ionic liquid, 1-butyl-3-methylimidazolium chloride ionic liquid, 1-butyl-3-methylimidazolium bromide ionic liquid, 1-ethyl-3-methylimidazolium acetate ionic liquid, 1-allyl-3-methylimidazolium chloride ionic liquid, 1-butyl-3-methylimidazolium bromide ionic liquid, 1-ethyl-3-methylimidazolium acetate ionic liquid, 1-allyl-3-methylimidazolium chloride ionic liquid, 1-butyl-3-methylimidazolium bromide ionic liquid, 1-ethyl-3-methylimidazolium acetate ionic liquid, 1-allyl-3-methylimidazolium chloride ionic liquid, 1-ethyl ... 1-Methylimidazolium acetate ionic liquid, 1-butyl-3-methylimidazolium acetate ionic liquid, N-ethylpyridine chloride ionic liquid, N-ethylpyridine bromide ionic liquid, 1,3-dimethylimidazolium dimethyl phosphate ionic liquid, 1-ethyl-3-methylimidazolium diethyl phosphate ionic liquid, 3-methylimidazolium carboxylate ionic liquid, N-methylpyridine carboxylate ionic liquid, 1-ethyl-3-methylimidazolium carboxylate ionic liquid, 1-butyl-3-methylimidazolium carboxylate ionic liquid;

[0031] In one embodiment, the carbonate or bicarbonate is selected from at least one of Li2CO3, NaHCO3, K2CO3, K2CO3, Cs2CO3, Rb2CO3, NH4HCO3, and (C(NH2)3)2CO3;

[0032] According to an embodiment of the present invention, the organic room temperature phosphorescent polymer material can be processed into material forms including but not limited to: films, inks, and coatings;

[0033] The preparation method of the film is as follows: dissolve the phosphorescent polymer material in a solvent to obtain a phosphorescent polymer solution with a mass concentration of 1-30%, then scrape the film with a film scraper and dry it to obtain a phosphorescent polymer film.

[0034] The preparation method of the ink is as follows: dissolve the phosphorescent polymer material in a solvent to obtain a phosphorescent ink with a mass concentration of 0.01-10%;

[0035] The preparation method of the coating is as follows: dissolve the phosphorescent polymer material in a solvent to obtain a phosphorescent coating with a mass concentration of 0.1-30%;

[0036] The solvent is selected from at least one of water, dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), chloroform, dichloromethane, 1,2-dichloroethane, acetone, tetrahydrofuran (THF), N-methylpyrrolidone, pyridine, ethanol, methanol, isopropanol, ethyl acetate, butyl acetate, toluene, and methyl ethyl ketone.

[0037] The present invention also provides the use of the organic room temperature phosphorescent polymer material as described above as a pH sensor, anti-counterfeiting and encryption material.

[0038] Beneficial effects

[0039] This invention, for the first time, utilizes a natural polysaccharide polymer as the main chain. By introducing aromatic carboxylate groups onto the main chain, intersystem crossing is promoted, enhancing the interaction between molecular chains, thus yielding a novel organic room-temperature phosphorescent polymer material. This material exhibits a long phosphorescence lifetime (on the order of seconds), overcoming the short lifetime (typically on the order of microseconds or milliseconds) of existing organic phosphorescent polymers. Furthermore, this material exhibits phosphorescence response at room temperature, a significant advantage over existing organic phosphorescent polymers that only emit light at low temperatures (77K). Finally, the polymer material possesses excellent processability and pH responsiveness, enabling the fabrication of phosphorescent films, coatings, and inks, showing significant application potential in anti-counterfeiting and encryption fields.

[0040] Terminology Definitions and Explanations

[0041] The numerical ranges described in this application specification and claims, when defined as "integers," should be understood to include both endpoints of the range and every integer within that range. For example, "integers from 0 to 10" should be understood to include every integer of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. This applies to "integers from 50 to 5000," "integers from 100 to 4000," etc., as described in the specification.

[0042] Term "C" 1-6 "Alkyl" should be understood to mean a straight-chain or branched saturated monovalent hydrocarbon group having 1, 2, 3, 4, 5, or 6 carbon atoms. The alkyl group is, for example, methyl, ethyl, propyl, butyl, pentyl, hexyl, isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, 2-methylbutyl, 1-methylbutyl, 1-ethylpropyl, 1,2-dimethylpropyl, neopentyl, 1,1-dimethylpropyl, 4-methylpentyl, 3-methylpentyl, 2-methylpentyl, 1-methylpentyl, 2-ethylbutyl, 1-ethylbutyl, 3,3-dimethylbutyl, 2,2-dimethylbutyl, 1,1-dimethylbutyl, 2,3-dimethylbutyl, 1,3-dimethylbutyl, or 1,2-dimethylbutyl, or their isomers. In particular, the group has 1, 2, or 3 carbon atoms ("C"). 1-3 Alkyl), such as methyl, ethyl, n-propyl or isopropyl. Attached Figure Description

[0043] Figure 1 The hydrogen nuclear magnetic resonance (NMR) spectrum of cellulose metaphenyl ester in Example 1. Testing instrument: Bruker AV400 NMR spectrometer; solvent: deuterated dimethyl sulfoxide (DMSO-d6).

[0044] Figure 2 Fluorescence and phosphorescence of lithium cellulose trimellitate in Example 1. Camera: Sony α7, excitation wavelength: 365nm.

[0045] Figure 3 Phosphorescence lifetime spectrum of lithium cellulose trimellitate in Example 1. Testing instrument: Edinburgh FLS980 steady-state and transient fluorescence spectrometer, excitation wavelength: 365 nm.

[0046] Figure 4 pH response behavior of the lithium metaphenylene cellulose printed pattern in Example 1. Camera: Sony α7, excitation wavelength: 365nm.

[0047] Figure 5 Fluorescence and phosphorescence spectra of sodium starch phthalate in Example 2. Testing instrument: HITACHI F-7000 spectrophotometer, excitation wavelength 365 nm.

[0048] Figure 6 The pH response performance of the sodium cellulose phthalate anti-counterfeiting pattern in Example 3 was measured by fluorescence and phosphorescence photographs with a 365nm UV lamp turned on and off. Detailed Implementation

[0049] The technical solution of the present invention will be further described in detail below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention, and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0050] Unless otherwise stated, the raw materials and reagents used in the following examples are commercially available products or can be prepared by known methods.

[0051] Example 1

[0052] 3 g of cellulose (DP 220) was dissolved in 57 g of 1-allyl-3-methylimidazolium chloride ionic liquid (AmimCl), 240 mg of 4-dimethylaminopyridine (DMAP) was added, and 5.1 g of trimellitic anhydride was added. The reaction was carried out at 80 °C for 8 h. After the reaction was completed, ethanol was added to the reaction system to terminate the reaction. The reaction solution was then precipitated in 300 mL of ethanol. During the washing process, about 1 mL of concentrated hydrochloric acid was added. The precipitate was then filtered, and the filter cake was washed three times with hydrochloric acid / ethanol solution (v / v, 0.3%) and once with ethanol. After filtration and vacuum drying, the final product, cellulose trimellitic ester, was obtained. Its proton NMR spectrum is shown below. Figure 1 As shown, the degree of substitution is 0.61.

[0053] Take 3g of cellulose metaphenyl ester, 1g of Li2CO3 and 30mL of ultrapure water, stir at room temperature for 12h, filter, dialyze the filtrate with water and dry to obtain the final product lithium cellulose metaphenyl ester.

[0054] Lithium metaphenylene cellulose emits blue fluorescence under 365 nm ultraviolet light irradiation, and emits green phosphorescence at room temperature for 4 seconds after the ultraviolet light is turned off. Figure 2 As shown. Its phosphorescence lifetime is 417 ms, as... Figure 3 As shown.

[0055] Lithium cellulose trimellitate is dissolved in water to obtain a 7% (w / w) solution, which can be used as ink to print on paper, resulting in a phosphorescent anti-counterfeiting pattern. Furthermore, the obtained pattern does not emit phosphorescence after being fumigated with hydrochloric acid vapor and dried, but it re-emits green phosphorescence after treatment with ammonia vapor and drying. Figure 4 As shown.

[0056] Example 2

[0057] 2.0 g of starch (DP 400) was dissolved in 48.0 g of 1-butyl-3-methylimidazolium chloride ionic liquid (BmimCl) / DMF (mass ratio 4:1), 150 mg of 4-dimethylaminopyridine (DMAP) was added, and 6.2 g of phthalic anhydride was added. The reaction was carried out at 80 °C for 9 h. After the reaction was completed, ethanol was added to the reaction system to terminate the reaction. The reaction solution was then precipitated in 300 mL of ethanol. During the washing process, about 1 mL of concentrated hydrochloric acid was added. The precipitate was then filtered, and the filter cake was washed three times with hydrochloric acid / ethanol solution (volume fraction 0.3%) and once with ethanol. The mixture was then filtered and dried under vacuum to obtain the final product, starch phthalate. The degree of substitution was confirmed by NMR to be 0.82.

[0058] Take 2g of starch phthalate, 1g of NaHCO3 and 30mL of ultrapure water and stir at room temperature for 12h. Filter, dialyze the filtrate with water and dry to obtain the final product sodium starch phthalate.

[0059] Sodium starch phthalate emits blue fluorescence under 365 nm ultraviolet light irradiation, and emits green phosphorescence for 2 seconds at room temperature after the ultraviolet light is turned off. Its fluorescence and phosphorescence spectra are as follows: Figure 5 As shown. Furthermore, the obtained pattern did not emit phosphorescence after being fumigated with hydrochloric acid vapor and dried, but it re-emits green phosphorescence after being treated with ammonia vapor and dried.

[0060] Example 3

[0061] 2.0 g of cellulose (DP 600) was dissolved in 48.0 g of 1-butyl-3-methylimidazolium chloride ionic liquid (BmimCl), 150 mg of 4-dimethylaminopyridine (DMAP) was added, and 10.0 g of phthalic anhydride was added. The reaction was carried out at 80 °C for 9 h. After the reaction was completed, ethanol was added to the reaction system to terminate the reaction. The reaction solution was then precipitated in 300 mL of ethanol. During the washing process, about 1 mL of concentrated hydrochloric acid was added. The precipitate was then filtered, and the filter cake was washed three times with hydrochloric acid / ethanol solution (v / v, 0.3%) and once with ethanol. The mixture was then filtered and dried under vacuum to obtain the final product, cellulose phthalate. The degree of substitution was confirmed by NMR to be 1.20.

[0062] Take 2g of cellulose phthalate, 1.5g of NaHCO3 and 50mL of ultrapure water, stir at room temperature for 12h, filter, dialyze the filtrate with water and dry to obtain the final product sodium cellulose phthalate.

[0063] Sodium cellulose phthalate emits blue fluorescence under 365nm ultraviolet light irradiation, and emits green phosphorescence at room temperature for 2 seconds after the ultraviolet light is turned off.

[0064] Sodium cellulose phthalate is dissolved in water to obtain a 7% (w / w) solution, which can be used as ink to print on paper, resulting in a phosphorescent anti-counterfeiting pattern. Furthermore, the obtained pattern does not emit phosphorescence after being fumigated with hydrochloric acid vapor and dried, but it re-emits green phosphorescence after treatment with ammonia vapor and drying. At this point, the phosphorescent pattern can be destroyed by hydrochloric acid vapor or water, preventing it from emitting phosphorescence. Figure 6 As shown.

[0065] Example 4

[0066] 2 g of chitosan (DP 800) was dissolved in 48 g of 1-ethyl-3-methylimidazolium acetate ionic liquid (EmimAc), 240 mg of 4-dimethylaminopyridine (DMAP) was added, and 8.0 g of trimellitic anhydride was added. The reaction was carried out at 80 °C for 8 h. After the reaction was completed, ethanol was added to the reaction system to terminate the reaction. The reaction solution was then precipitated in 300 mL of ethanol. During the washing process, about 1 mL of concentrated hydrochloric acid was added. The precipitate was then filtered, and the filter cake was washed three times with hydrochloric acid / ethanol solution (volume fraction 0.3%) and once with ethanol. The mixture was then filtered and dried under vacuum to obtain the final product, chitosan trimellitic ester. The degree of substitution was confirmed by NMR to be 0.95.

[0067] Take 3g of chitosan metaphenyl ester, 1g of Li2CO3 and 50mL of ultrapure water and stir at room temperature for 12h. Filter, dialyze the filtrate with water and dry to obtain the final product lithium chitosan metaphenyl ester.

[0068] Lithium chitosan-based phosphors emit blue fluorescence under 365 nm UV light irradiation and green phosphorescence at room temperature after the UV light is turned off. Furthermore, the resulting pattern does not emit phosphorescence after fumigation with hydrochloric acid vapor and drying, but regains green phosphorescence after treatment with ammonia vapor and drying.

[0069] Example 5

[0070] 3 g of cellulose (DP 800) was dissolved in 57 g of 1-allyl-3-methylimidazolium chloride ionic liquid (AmimCl), 240 mg of 4-dimethylaminopyridine (DMAP) was added, and 10.2 g of 3,4-thiophene dicarboxylic anhydride was added. The reaction was allowed to proceed for 8 h. After the reaction was completed, ethanol was added to the reaction system to terminate the reaction. The reaction solution was then precipitated in 300 mL of ethanol. During the washing process, approximately 1 mL of concentrated hydrochloric acid was added. The precipitate was then filtered, and the filter cake was washed three times with hydrochloric acid / ethanol solution (v / v, 0.3%) and once with ethanol. The mixture was then filtered and dried under vacuum to obtain the final product, cellulose 3,4-thiophene dicarboxylic acid ester. NMR characterization confirmed that its degree of substitution was 1.42.

[0071] Take 3g of cellulose 3,4-thiophene dicarboxylate, 1g of Li2CO3 and 50mL of ultrapure water, stir for 12h, filter, dialyze the filtrate with water and dry to obtain the final product lithium cellulose 3,4-thiophene dicarboxylate.

[0072] Lithium 3,4-thiophene dicarboxylate of cellulose emits blue fluorescence under 365 nm ultraviolet light irradiation and green phosphorescence at room temperature after the ultraviolet light is turned off. In addition, the obtained pattern does not emit phosphorescence after being fumigated with hydrochloric acid vapor and dried, but re-emits green phosphorescence after being treated with ammonia vapor and dried.

[0073] Example 6

[0074] 3 g of cellulose (DP 650) was dissolved in 57 g of 1-allyl-3-methylimidazolium chloride ionic liquid (AmimCl), 240 mg of 4-dimethylaminopyridine (DMAP) was added, and 6.0 g of 2,3-pyridinedicarboxylic anhydride was added. The reaction was carried out at 80 °C for 8 h. After the reaction was completed, ethanol was added to the reaction system to terminate the reaction. The reaction solution was then precipitated in 300 mL of ethanol. During the washing process, about 1 mL of concentrated hydrochloric acid was added. The precipitate was then filtered, and the filter cake was washed three times with hydrochloric acid / ethanol solution (v / v, 0.3%) and once with ethanol. The mixture was then filtered and dried under vacuum to obtain the final product, cellulose 2,3-pyridinedicarboxylic acid ester. NMR characterization confirmed that its degree of substitution was 0.51.

[0075] Take 3g of cellulose 2,3-pyridine dicarboxylate, 1g of Li2CO3 and 50mL of ultrapure water, stir at room temperature for 12h, filter, dialyze the filtrate with water and dry to obtain the final product lithium cellulose 2,3-pyridine dicarboxylate.

[0076] Lithium 2,3-pyridinedicarboxylate of cellulose emits blue fluorescence under 365 nm ultraviolet light irradiation and green phosphorescence at room temperature after the ultraviolet light is turned off. In addition, the obtained pattern does not emit phosphorescence after being fumigated with hydrochloric acid vapor and dried, but re-emits green phosphorescence after being treated with ammonia vapor and dried.

[0077] Example 7

[0078] Take 1g of the lithium cellulose trimellitate prepared in Example 1 and dissolve it in 13mL of ultrapure water to obtain a solution with a mass concentration of 7%. This solution can be used directly as a coating to form on substrates such as ceramics, iron, and plastics; the solution can also be added to a glass plate covered with a mold and dried to obtain the corresponding phosphorescent film; or the solution can be used as ink material for printers to print on paper to obtain phosphorescent anti-counterfeiting patterns.

[0079] The embodiments of the present invention have been described above. However, the present invention is not limited to the above embodiments. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An organic room-temperature phosphorescent polymer material, characterized in that, It has the structure shown in Equation I: Formula I in: A1, A2, and A3 may be the same or different, and are independently selected from H, -C(=O)-CH3, or aromatic carboxylate group R2; Y is selected from O or NH; The aromatic carboxylate group R2 is selected from at least one of the following structures: This is the connection point; Cation M For: Na + Li + K + 、Rb + Cs + NH4 + C(NH2)3 + At least one of them; Group X is: H, F, Cl, Br, I, NO2, C CH, CH=CH2, COOM ,-NH-C(=O)-CH3,OH,-C(=O)-C C-Ph, C 1-6 At least one of the alkyl groups; The main chain is a polysaccharide, and the degree of polymerization (DP) of the polysaccharide is an integer between 50 and 5000. The main chain of the organic room-temperature phosphorescent polymer material is a natural polysaccharide. The natural polysaccharide is at least one of cellulose, starch, chitosan, and chitin; The degree of substitution of the aromatic carboxylate group R2 in the polysaccharide is 0.2-2.

0.

2. The organic room-temperature phosphorescent polymer material according to claim 1, characterized in that, The degree of aggregation DP is an integer between 100 and 4000.

3. The organic room-temperature phosphorescent polymer material according to claim 1, characterized in that, The degree of substitution of the aromatic carboxylate group R2 in the polysaccharide is 0.5-1.

5.

4. The method for preparing the organic room-temperature phosphorescent polymer material according to any one of claims 1-3, characterized in that, Includes the following steps: The polysaccharide is dissolved in a solvent to obtain a polysaccharide solution; an acylation reagent is added to the obtained polysaccharide solution to carry out the reaction and obtain a polysaccharide ester; the polysaccharide ester is mixed and stirred with an aqueous solution of carbonate or bicarbonate. The acylation reagent is selected from acid anhydrides, acyl chlorides, or carboxylic acids containing the aromatic carboxylic acid group R2 after removing M; The solvent is selected from ionic liquids.

5. The preparation method according to claim 4, characterized in that, The molar ratio of the polysaccharide to the acylation reagent is 10:1 to 1:

10.

6. The preparation method according to claim 4, characterized in that, The acylation reagent is selected from at least one of the following anhydrides, either unsubstituted or optionally substituted with one, two or more groups X: phthalic anhydride, trimellitic anhydride, 2,3-anthracite anhydride, 1,8-naphthalenedicarboxylic anhydride, perylene-3,4-dicarboxylic anhydride, 2,2'-biphenyl anhydride, phenylmaleic anhydride, 2,3-pyridinedicarboxylic anhydride, 2,3-thiophenedicarboxylic anhydride, and 3,4-thiophenedicarboxylic anhydride; the group X is selected from at least one of the following groups: F, Cl, Br, I, NO2, alkynyl, CH=CH2, COOM. ,-NH-C(=O)-CH3,OH,-C(=O)-C C-Ph, C 1-6 alkyl.

7. The preparation method according to any one of claims 4-6, characterized in that, The solvent is selected from at least one of the following: 1-ethyl-3-methylimidazolium chloride ionic liquid, 1-ethyl-3-methylimidazolium bromide ionic liquid, 1-allyl-3-methylimidazolium chloride ionic liquid, 1-allyl-3-methylimidazolium bromide ionic liquid, 1-butyl-3-methylimidazolium chloride ionic liquid, 1-butyl-3-methylimidazolium bromide ionic liquid, 1-ethyl-3-methylimidazolium acetate ionic liquid, 1-allyl-3-methylimidazolium acetate ionic liquid, 1-butyl-3-methylimidazolium acetate ionic liquid, N-ethylpyridine chloride ionic liquid, N-ethylpyridine bromide ionic liquid, 1,3-dimethylimidazolium dimethyl phosphate ionic liquid, 1-ethyl-3-methylimidazolium diethyl phosphate ionic liquid, 3-methylimidazolium carboxylate ionic liquid, N-methylpyridine carboxylate ionic liquid, 1-ethyl-3-methylimidazolium carboxylate ionic liquid, 1-butyl-3-methylimidazolium carboxylate ionic liquid.

8. The preparation method according to any one of claims 4-6, characterized in that, The carbonate or bicarbonate is selected from at least one of Li2CO3, NaHCO3, K2CO3, Cs2CO3, Rb2CO3, NH4HCO3, and (C(NH2)3)2CO3.

9. The preparation method according to any one of claims 4-6, characterized in that, The organic room temperature phosphorescent polymer material is processed into the following forms: film, ink, coating.

10. The use of the organic room-temperature phosphorescent polymer material according to any one of claims 1-3 as a pH sensor, anti-counterfeiting and encryption material.

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