A cellulose-based film with temperature and ph stimuli response and its preparation method and application

Abstract

The application belongs to the technical field of anti-counterfeiting films, and specifically discloses a cellulose-based film with temperature and pH stimulus response, a preparation method thereof and application, wherein a cellulose-based macromolecular RAFT reagent is prepared, in-situ surface-initiated RAFT polymerization is performed, and a chain segment with stimulus response, an aggregation-induced emission light chain segment and a fluorescent polymer chain segment with controllable color change are synchronously introduced, so that the cellulose-based film with temperature and pH stimulus response is prepared in one step and quickly, and the film can be used to prepare a dynamic anti-counterfeiting film; the preparation method adopts biodegradable cellulose as raw material, and has the advantages of being green, environmentally-friendly and low-carbon.

Description

Technical Field

[0001] The present invention relates to the technical field of anti-counterfeiting films, in particular to a cellulose-based film responsive to temperature and pH stimulation, and a preparation method and application thereof. Background Art

[0002] With the continuous advancement of technology and the advent of the digital age, the proliferation of counterfeit goods and information leaks has become increasingly prevalent, resulting in substantial economic losses each year. To address these issues and protect the integrity of goods and information, a wide range of anti-counterfeiting and encryption technologies have been developed, including quick response codes, holograms, color conversion, photoluminescence patterns, and stimuli-responsiveness. However, these methods often exhibit disadvantages such as easy counterfeiting, high production costs, complex manufacturing processes, and cumbersome detection procedures.

[0003] Fluorescence-based anti-counterfeiting and dynamic encryption technologies have become prominent solutions in this field due to their inherent properties of stealth, ease of design and implementation, and direct verifiability. The use of fluorescent dyes in anti-counterfeiting applications ensures product authenticity and effectively prevents substandard and counterfeit products from entering the market. In the field of information security, fluorescent encryption technology provides protection by encoding sensitive data during transmission and storage, thereby preventing unauthorized access and manipulation. Common fluorescent anti-counterfeiting and information encryption materials include traditional organic fluorescent materials, quantum dot materials, rare earth coordination materials, and phosphorescent materials. However, these materials often suffer from aggregation-induced detonation (ACQ) phenomena, are complex to synthesize, and simple information encryption methods are easily replicated.

[0004] The discovery of aggregation-induced emission materials solves the ACQ problem. In their aggregated state, they exhibit excellent resistance to photobleaching, can adjust their molecular structure and chemical bonds to achieve different luminescence colors and wavelengths, and can incorporate different functional groups to achieve diverse stimulus responses. Furthermore, dynamic fluorescence anti-counterfeiting technology, which dynamically changes fluorescence in response to external stimuli, is a more advanced and difficult-to-forge and circumvent anti-counterfeiting technology, offering enhanced security and reliability.

[0005] Therefore, a simple and rapid method is developed to prepare a stimulus-responsive cellulose-based dynamic anti-counterfeiting film. By regulating the external stimulus source, the emission wavelength of the anti-counterfeiting film is changed, thereby presenting different color changes. In the field of dynamic anti-counterfeiting and dynamic information encryption, it can greatly increase the difficulty of counterfeiting and has potential application value. Summary of the Invention

[0006] In order to solve the above technical problems, the present invention provides a cellulose-based membrane responsive to temperature and pH stimulation, and a preparation method and application thereof.

[0007] To achieve the above object, the present invention is implemented according to the following technical solutions:

[0008] One of the technical solutions of the present application is to provide a preparation method of a cellulose-based film with temperature and pH stimulus response, comprising the following steps:

[0009] S1, mix cellulose and ionic liquid with a mass ratio of 1:(10-50), after heating and stirring to dissolve, add N,N-dimethylformamide solvent for dilution, the mass ratio of N,N-dimethylformamide to ionic liquid is (1-3):(1-3); then add 2-bromopropyl bromide in an ice water bath, the mass ratio of cellulose to 2-bromopropyl bromide is 1:(5-20), after 48h reaction at room temperature, precipitate in deionized water, centrifuge, wash and dry to obtain cellulose-based initiator;

[0010] S2, mix cellulose-based initiator and dimethyl sulfoxide solvent with a mass ratio of 1:(15-30) at 30-60℃ to obtain reaction liquid A; mix benzyl mercaptan and triethylamine with a mass ratio of (1-3):1 and react for 30min, then add carbon disulfide, the mass ratio of benzyl mercaptan to carbon disulfide is 1:(1-5), continue to stir for 30min to obtain reaction liquid B; mix reaction liquid A and reaction liquid B, stir at 30-80℃ for 24h, then precipitate with deionized water, centrifuge, wash and dry to obtain cellulose-based macromolecular RAFT reagent;

[0011] S3, dissolve the cellulose-based macromolecular RAFT reagent in dioxane, then add phenylboronic acid derivative, the molar ratio of cellulose-based macromolecular RAFT reagent to phenylboronic acid derivative is 1:(1-5), after heating reaction for 8-12h, obtain modified cellulose-based macromolecular RAFT reagent; take stimulus response monomer, aggregation-induced emission fluorescent polymerization monomer, fluorescent polymer chain segment with color controllable change, modified cellulose-based macromolecular RAFT reagent and initiator with a mass ratio of (200-600):(0.1-24):(0.02-6):(2-60):(0.2-12), add them to organic solvent, bubble with nitrogen for 30min, then place in an oil bath pot for 12-24h of reaction, after the reaction is completed, drop the reaction liquid into n-hexane solvent for precipitation three times, vacuum dry to obtain cellulose-based graft copolymer;

[0012] S4, dissolve the above cellulose-based graft copolymer in organic solvent, after stirring reaction for 1-5h after adding crosslinking agent, coat on the surface of filter paper to obtain cellulose-based film with temperature and pH stimulus response.

[0013] Further, the cellulose is one or more of microcrystalline cellulose, ethyl cellulose and carboxymethyl cellulose.

[0014] Further, the ionic liquid is one or more of 1-allyl-3-methylimidazolium chloride (AMIMCl), 1-butyl-3-methylimidazolium chloride (BMIMCl), 1-ethyl-3-methylimidazolium chloride (EMIMCl), 1-methyl-3-butylimidazolium chloride (MMIMCl), 1-butyl-3-methylimidazolium propionamide (BMIMAc), and 1-butyl-3-methylimidazolium acetate (BMIMOAc).

[0015] Further, the stimuli-responsive monomer is one or more of acrylic acid, methacrylic acid, N-isopropyl acrylamide, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, N-ethyl methacrylamide, N-pyrrolidinyl acrylamide, N-cyclopropyl methacrylamide, 2-methoxyethyl acrylate, polyethylene glycol methyl ether methacrylate, polyethylene glycol methyl ether acrylate, and methacryloyl ethyl sulfobetaine.

[0016] Further, the aggregation-induced emission fluorescent polymerization monomer is a tetraphenylstyrene derivative, which has the following structural formula:

[0017]

[0018] wherein the group R is one of a vinyl group, a propenyl group, an acrylate group, a methacrylate group, and an acrylamide group; more preferably, the group R in the tetraphenylstyrene derivative is a vinyl group.

[0019] The color-controllable fluorescent polymer segment is a spiropyran derivative, which has the following structural formula:

[0020]

[0021] wherein the group R is one of a vinyl group, a propenyl group, an acrylate group, a methacrylate group, and an acrylamide group; more preferably, the group R in the tetraphenylstyrene derivative is a vinyl group.

[0022] The boronic acid derivative is one or more of 4-formylphenyl boronic acid, 4-hydroxyphenyl boronic acid, 4-carboxymethylphenyl boronic acid, and 4-aminophenyl boronic acid.

[0023] Further, the initiator is any one or more of azobisisobutyronitrile, azobisisoheptyl nitrile, benzoyl peroxide, tert-butyl hydroperoxide, and tert-butyl peroxybenzoate.

[0024] Further, the organic solvent is one or more of toluene, acetone, dioxane, tetrahydrofuran, N,N-dimethylformamide, and dimethyl sulfoxide.

[0025] Furthermore, the cross-linking agent is one or more of 1,4-butanediamine, ethylenediamine, 1,5-pentanediamine, and 1,6-hexamethylenediisocyanate.

[0026] The second technical solution of the present invention is to provide a cellulose-based membrane that is responsive to temperature and pH stimulation and is prepared using the above method.

[0027] The third technical solution of the present invention is to provide an application of a cellulose-based film responsive to temperature and pH stimulation in the preparation of a dynamic anti-counterfeiting film.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] (1) The present invention prepares a cellulose-based macromolecular RAFT agent, initiates RAFT polymerization through in situ surface initiation, and simultaneously introduces stimulus-responsive segments, aggregation-induced luminescent segments, and color-controllable fluorescent polymer segments to rapidly prepare a cellulose-based membrane that responds to temperature and pH stimuli in one step. The membrane can be used to prepare a dynamic anti-counterfeiting membrane. The preparation method uses biodegradable cellulose as a raw material and has the advantages of being green, environmentally friendly, and low-carbon.

[0030] (2) The cellulose-based membrane with temperature and pH stimulus response prepared by the present invention has rapid stimulus response to temperature, pH and ultraviolet light. At the same time, it has good adhesion on the surfaces of different substrates and has good universality.

[0031] (3) The temperature- and pH-responsive cellulose-based membrane prepared by the present invention can change the luminescence spectrum of the fluorescent film by regulating parameters such as temperature, pH, and UV illumination time. It has significant dynamic and controllable photoluminescence performance and can be used in dynamic anti-counterfeiting applications. Leveraging this property, it can be applied in the fields of dynamic anti-counterfeiting and dynamic information encryption, greatly increasing the difficulty of counterfeiting. The preparation method of this material is simple, environmentally friendly, and has potential application value in the field of dynamic anti-counterfeiting. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The dynamic anti-counterfeiting film prepared by coating the stimulus-responsive cellulose-based graft copolymer Cell-gP (DMAEMA-co-TPEE-co-SPMA) obtained in Example 1 on filter paper is shown in the following figures after irradiation with 365nm UV light for 1s and 60s: (a) irradiation for 1s; (b) irradiation for 60s.

[0033] Figure 2The dynamic anti-counterfeiting film prepared by coating the stimulus-responsive cellulose-based graft copolymer Cell-gP (DMAEMA-co-TPEE-co-SPMA) obtained in Example 2 on filter paper was heated to 60°C and irradiated under 365nm UV light for 1s and 60s: (a) irradiation for 1s; (b) irradiation for 60s.

[0034] Figure 3 The dynamic anti-counterfeiting film prepared by coating the stimulus-responsive cellulose-based graft copolymer Cell-gP (DMAEMA-co-TPEE-co-SPMA) obtained in Example 3 on filter paper was immersed in an aqueous solution with a pH value of 8 for 60 seconds and irradiated under 365nm ultraviolet light for 1 second and 60 seconds. The effect diagram is as follows: (a) is irradiated for 1 second; (b) is irradiated for 60 seconds. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. The specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0036] Example 1

[0037] 1) Add microcrystalline cellulose Cell (10 g) and ionic liquid 1-allyl-3-methylimidazole chloride (AMIMCl) (200 g) to a 500 mL single-necked flask, heat to 100 ° C and stir to dissolve, then add N, N-dimethylformamide (100 g), continue stirring for 30 minutes, and then add 2-bromopropyl bromide (80 g) dropwise in an ice-water bath. After reacting at room temperature for 48 hours, precipitate in deionized water, centrifuge, wash, and vacuum dry to obtain a cellulose-based initiator.

[0038] 2) Add cellulose-based initiator (10 g) to dimethyl sulfoxide solvent, heat and stir at 40°C to dissolve to obtain reaction solution A. In another round-bottom flask, add benzyl mercaptan (2 g), triethylamine (1.6 g) and dimethyl sulfoxide (20 g), stir at room temperature for 30 minutes, then add carbon disulfide (3.6 g), and continue stirring for 30 minutes to obtain reaction solution B. The above reaction solutions A and B are mixed, heated to 40°C and stirred for 24 hours, and then precipitated with deionized water. After centrifugation, washing, and drying, a cellulose-based macromolecular RAFT agent (Cell-RAFT) is obtained.

[0039] 3) Cell-RAFT (0.46 g containing 0.5 mmol trisulfide function) and 4-formylphenylboronic acid (0.225 g, 1.5 mmol) were dissolved in 20 mL of dioxane and stirred for 2 h. Then, dimethylaminoethyl methacrylate (DMAEMA) (15.72 g, 100 mmol), (2-(4-vinylphenyl)ethylene-1,1,2-triyl)triphenyl (TPEE) (0.157 g, 1% wt), 1'-acryloyl chloride-3',3'-dimethyl-6-nitro(2H-1-benzopyran-2,2'-indole) (SPMA) (0.016 g, 0.1% wt) and azobisisobutyronitrile (AIBN) (10 mg, 0.06 mmol) were dissolved in 20 mL of dioxane. After nitrogen bubbling for 30 min, the mixture was placed in an oil bath and heated for 24 h. After the reaction, the reaction solution was added dropwise to a n-hexane solvent for precipitation three times, and then dried in vacuo to obtain the stimulus-responsive cross-linked cellulose-based graft copolymer Cell-gP (DMAEMA-co-TPEE-co-SPMA).

[0040] 4) The stimulus-responsive cellulose-based graft copolymer Cell-gP (DMAEMA-co-TPEE-co-SPMA) (5.0 g) was dissolved in acetone to prepare a polymer solution with a mass concentration of 10%, 1,4-diaminobutane crosslinker (0.5 mL) was added, and the mixture was stirred for 1 h before being coated on the surface of filter paper. After drying at 40 ° C, a dynamic anti-counterfeiting film with a cross-linked structure and temperature and pH stimulus response was obtained. The effect after irradiation under 365 nm ultraviolet light for 1 s and 60 s is shown in the figure. Figure 1 As shown by Figure 1 It can be seen that after 60 seconds of ultraviolet light irradiation, the luminescent color of the obtained cellulose-based film gradually changes to orange, showing dynamic photoluminescence characteristics.

[0041] Example 2

[0042] 1) Add microcrystalline cellulose Cell (10 g) and ionic liquid 1-allyl-3-methylimidazole chloride (AMIMCl) (200 g) to a 500 mL single-necked flask, heat to 100 ° C and stir to dissolve, then add N, N-dimethylformamide (100 g), continue stirring for 30 minutes, and then add 2-bromopropyl bromide (80 g) dropwise in an ice-water bath. After reacting at room temperature for 48 hours, precipitate in deionized water, centrifuge, wash, and vacuum dry to obtain a cellulose-based initiator.

[0043] 2) Add cellulose-based initiator (10 g) to dimethyl sulfoxide solvent, heat and stir at 40°C to dissolve to obtain reaction solution A. In another round-bottom flask, add benzyl mercaptan (2 g), triethylamine (1.6 g) and dimethyl sulfoxide (20 g), stir at room temperature for 30 minutes, then add carbon disulfide (3.6 g), and continue stirring for 30 minutes to obtain reaction solution B. The above reaction solutions A and B are mixed, heated to 40°C and stirred for 24 hours, and then precipitated with deionized water. After centrifugation, washing, and drying, a cellulose-based macromolecular RAFT agent (Cell-RAFT) is obtained.

[0044] 3) Cell-RAFT (0.46 g containing 0.5 mmol trisulfide function) and 4-formylphenylboronic acid (0.225 g, 1.5 mmol) were dissolved in 20 mL of dioxane and stirred for 2 h. Then, dimethylaminoethyl methacrylate (DMAEMA) (23.58 g, 150 mmol), (2-(4-vinylphenyl)ethylene-1,1,2-triyl)triphenyl (TPEE) (0.12 g, 0.5% wt), 1'-acryloyl chloride-3',3'-dimethyl-6-nitro(2H-1-benzopyran-2,2'-indole) (SPMA) (0.024 g, 0.1% wt) and azobisisobutyronitrile (AIBN) (15 mg, 0.09 mmol) were added and dissolved in 20 mL of dioxane. After nitrogen bubbling for 30 min, the mixture was placed in an oil bath and heated for 24 h. After the reaction, the reaction solution was added dropwise to a n-hexane solvent for precipitation three times, and then dried in vacuo to obtain the stimulus-responsive cross-linked cellulose-based graft copolymer Cell-gP (DMAEMA-co-TPEE-co-SPMA).

[0045] 4) The stimulus-responsive cellulose-based graft copolymer Cell-gP (DMAEMA-co-TPEE-co-SPMA) (5.0 g) was dissolved in acetone to prepare a polymer solution with a mass concentration of 10%. 1,4-Butanediamine crosslinker (0.5 mL) was added and stirred for 1 h. The solution was then coated on the filter paper surface and dried at 40 ° C to obtain a dynamic anti-counterfeiting film with a cross-linked structure. The film was immersed in deionized water, heated to 60 ° C, and irradiated under 365 nm ultraviolet light for 1 s and 60 s. The effect is shown in the figure. Figure 2 As shown. Figure 2It can be seen that by adjusting the temperature to 60°C, which is higher than the lowest common solubility temperature (LCST) of the cellulose-based graft copolymer Cell-g-P(DMAEMA-co-TPEE-co-SPMA), the solubility of the PDMAEMA segment in water is reduced, aggregation occurs, and the aggregation-induced luminescence segment PTPEE emits light, thereby emitting blue light under ultraviolet light irradiation for 1s, showing a clear aggregation-induced luminescence (AIE) effect; at the same time, with the extension of the light irradiation time, the color-controllable luminescence segment PSPMA emits light from colorless to orange-red, and the luminescence color of PTPEE and the luminescence color of PSPMA are superimposed, resulting in dynamic color change, which can be used for dynamic anti-counterfeiting and information encryption.

[0046] Example 3

[0047] 1), in a 500 mL single-necked flask, microcrystalline cellulose Cell (10 g) and ionic liquid 1-allyl-3-methylimidazole chloride (AMIMCl) (200 g) were added, heated to 100°C and stirred to dissolve, then N,N-dimethylformamide (100 g) was added, and after continuous stirring for 30 min, 2-bromopropyl bromide (80 g) was added dropwise in an ice water bath, and after room temperature reaction for 48 h, it was precipitated with deionized water, centrifuged, washed, and vacuum dried to obtain a cellulose-based initiator.

[0048] 2), the cellulose-based initiator (10 g) was added to dimethyl sulfoxide solvent, heated and stirred to dissolve at 40°C to obtain reaction liquid A. In another round-bottom flask, benzyl mercaptan (2 g), triethylamine (1.6 g) and dimethyl sulfoxide (20 g) were added, stirred at room temperature for 30 min, then carbon disulfide (3.6 g) was added, and after continuous stirring for 30 min, reaction liquid B was obtained. Mix reaction liquid A and reaction liquid B, heat to 40°C and stir for 24 h, then precipitate with deionized water, centrifuge, wash and dry to obtain a cellulose-based macromolecular RAFT agent (Cell-RAFT).

[0049] 3) Cell-RAFT (0.46 g containing 0.5 mmol trisulfide function) and 4-formylphenylboronic acid (0.225 g, 1.5 mmol) were dissolved in 20 mL of dioxane and stirred for 2 h. Then, dimethylaminoethyl methacrylate (DMAEMA) (23.58 g, 150 mmol), (2-(4-vinylphenyl)ethylene-1,1,2-triyl)triphenyl (TPEE) (0.12 g, 0.5% wt), 1'-acryloyl chloride-3',3'-dimethyl-6-nitro(2H-1-benzopyran-2,2'-indole) (SPMA) (0.024 g, 0.1% wt) and azobisisobutyronitrile (AIBN) (15 mg, 0.09 mmol) were added and dissolved in 20 mL of dioxane. After nitrogen bubbling for 30 min, the mixture was placed in an oil bath and heated for 24 h. After the reaction is completed, the reaction solution is added dropwise to a n-hexane solvent for precipitation three times, and then dried in vacuo to obtain the stimulus-responsive cellulose-based cross-linked graft copolymer Cell-gP (DMAEMA-co-TPEE-co-SPMA).

[0050] 4) The stimulus-responsive cellulose-based graft copolymer Cell-gP (DMAEMA-co-TPEE-co-SPMA) (5.0 g) was dissolved in acetone to prepare a polymer solution with a mass concentration of 10%. 1,4-Butanediamine crosslinker (0.5 mL) was added and stirred for 1 h before coating on the surface of filter paper. After drying at 40 ° C, a dynamic anti-counterfeiting film with a cross-linked structure was obtained. The film was immersed in an aqueous solution with a pH value of 8 for 60 s and irradiated under 365 nm ultraviolet light for 1 s and 60 s. The effect is shown in the figure. Figure 3 As shown. Figure 3 It can be seen that by adjusting the pH to 8, the PDMAEMA chain segments in the cellulose-based graft copolymer Cell-gP (DMAEMA-co-TPEE-co-SPMA) curled and aggregated, reducing its solubility in water, causing the aggregation-induced luminescence chain segment PTPEE to aggregate and emit light, and then emit blue light when irradiated with ultraviolet light for 1 second, showing an obvious aggregation-induced emission (AIE) effect; at the same time, as the illumination time increases, the color-controllable luminescence chain segment PSPMA gradually changes from colorless to orange-red, and the PTPEE luminescence color and the PSPMA luminescence color are superimposed to obtain dynamic color changes, which can be used for dynamic anti-counterfeiting and information encryption.

[0051] In summary, the cellulose-based film prepared by the present invention with temperature and pH stimulus response can change the luminescence spectrum of the fluorescent film by regulating parameters such as temperature, pH, and ultraviolet light irradiation time. It has obvious dynamic and controllable photoluminescence properties and can be used for dynamic anti-counterfeiting applications.

[0052] The technical solution of the present invention is not limited to the above-mentioned specific embodiments. Any technical variations made according to the technical solution of the present invention fall within the protection scope of the present invention.

Claims

1. A method for preparing a cellulose-based membrane responsive to temperature and pH stimulation, characterized in that: The following steps are involved: S1. Mix cellulose and ionic liquid in a mass ratio of 1:(10-50), heat and stir to dissolve, and then add N,N-dimethylformamide solvent to dilute. The mass ratio of N,N-dimethylformamide to ionic liquid is (1-3):(1-3). Then, add 2-bromopropyl bromide in an ice-water bath. The mass ratio of cellulose to 2-bromopropyl bromide is 1:(5-20). After reacting at room temperature for 48 hours, precipitate in deionized water, centrifuge, wash, and dry to obtain a cellulose-based initiator. S2. A cellulose-based initiator and a dimethyl sulfoxide solvent in a mass ratio of 1:(15-30) are mixed at 30°C-60°C to obtain a reaction solution A; benzyl mercaptan and triethylamine in a mass ratio of (1-3:1) are mixed and reacted for 30 minutes, and then carbon disulfide is added, with the mass ratio of benzyl mercaptan to carbon disulfide being 1:(1-5), and stirring is continued for 30 minutes to obtain a reaction solution B; reaction solutions A and B are mixed, heated at 30°C-80°C and stirred for 24 hours, and then precipitated with deionized water, centrifuged, washed, and dried to obtain a cellulose-based macromolecular RAFT agent; S3. After dissolving a cellulose-based macromolecular RAFT agent in dioxane, a phenylboronic acid derivative is added, and the molar ratio of the cellulose-based macromolecular RAFT agent to the phenylboronic acid derivative is 1: (1-5). After heating for 8-12 hours, a modified cellulose-based macromolecular RAFT agent is obtained. Stimuli-responsive monomers, aggregation-induced emission fluorescent polymerization monomers, color-controllable fluorescent polymer segments, modified cellulose-based macromolecular RAFT agents, and initiators are added to an organic solvent in a mass ratio of (200-600): (0.1-24): (0.02-6): (2-60): (0.2-12). After nitrogen bubbling for 30 minutes, the mixture is placed in an oil bath and reacted for 12-24 hours. After the reaction, the reaction solution is added dropwise to a n-hexane solvent for precipitation three times, and vacuum dried to obtain a cellulose-based graft copolymer. The color-controllable fluorescent polymer segment is a spiropyran derivative, and its structural formula is as follows: ； Wherein, the group R is one of vinyl, propenyl, acrylate, and methacrylate; S4. Dissolve the above-mentioned cellulose-based graft copolymer in an organic solvent, add a cross-linking agent, stir and react for 1-5 hours, and then coat it on the surface of filter paper to obtain a cellulose-based membrane that responds to temperature and pH stimuli.

2. The method for preparing a cellulose-based film responsive to temperature and pH stimulation according to claim 1, wherein: The cellulose is one or more of microcrystalline cellulose, ethyl cellulose and carboxymethyl cellulose.

3. The method for preparing a cellulose-based film responsive to temperature and pH stimulation according to claim 1, wherein: The ionic liquid is one or more of 1-allyl-3-methylimidazolium chloride (AMIMCl), 1-butyl-3-methylimidazolium chloride (BMIMCl), 1-ethyl-3-methylimidazolium chloride (EMIMCl), 1-methyl-3-butylimidazolium chloride (MMIMCl), 1-butyl-3-methylimidazolium propionamide (BMIMAc) and 1-butyl-3-methylimidazolium acetate (BMIMOAc).

4. The method for preparing a cellulose-based film responsive to temperature and pH stimulation according to claim 1, wherein: The stimulus-responsive monomer is one or more of acrylic acid, methacrylic acid, N-isopropylacrylamide, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, N-ethylmethacrylamide, N-pyrrolidinoacrylamide, N-cyclopropylmethacrylamide, 2-methoxyethyl acrylate, polyethylene glycol methyl ether methacrylate, polyethylene glycol methyl ether acrylate, and methacryloylethyl sulfobetaine.

5. The method for preparing a cellulose-based film responsive to temperature and pH stimulation according to claim 1, wherein: The aggregation-induced luminescence fluorescent polymer monomer is a tetraphenylethylene derivative; the phenylboronic acid derivative is one or more of 4-formylphenylboronic acid, 4-hydroxyphenylboronic acid, 4-carboxymethylphenylboronic acid, and 4-aminophenylboronic acid.

6. The method for preparing a cellulose-based film responsive to temperature and pH stimulation according to claim 1, wherein: The initiator is any one or more of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, tert-butyl hydroperoxide, and tert-butyl perbenzoate.

7. The method for preparing a cellulose-based film responsive to temperature and pH stimulation according to claim 1, wherein: The organic solvent is one or more of toluene, acetone, dioxane, tetrahydrofuran, N,N-dimethylformamide, and dimethyl sulfoxide.

8. The method for preparing a cellulose-based film responsive to temperature and pH stimulation according to claim 1, wherein: The cross-linking agent is one or more of 1,4-butanediamine, ethylenediamine, 1,5-pentanediamine, and 1,6-hexamethylenediisocyanate.

9. A cellulose-based film responsive to temperature and pH stimulation prepared by the method according to any one of claims 1 to 8.

10. Use of the cellulose-based film responsive to temperature and pH stimulation as claimed in claim 9 in preparing a dynamic anti-counterfeiting film.

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