Stimulus-responsive dynamically adjustable multicolor luminescent eutectic gel, and preparation method and application thereof

Abstract

The invention provides stimuli-responsive dynamic adjustable multicolor luminescent eutectic gel as well as a preparation method and application thereof, and belongs to the technical field of stimuli-responsive fluorescent falsification prevention. A novel multifunctional eutectic gel material system is constructed on the basis of a bionic strategy, multifunctional integration of material performance is achieved through molecular design, and the Al < 3 + > stimulus-responsive dynamic adjustable multicolor luminescent fluorescent eutectic gel with environmental adaptability and surface self-adaptive adhesion performance is obtained. The material has excellent environmental stability and dynamic adjustable multicolor luminescence characteristics, and has potential application value in the field of multistage anti-counterfeiting science (information encryption and decryption).

Description

Technical Field

[0001] The present invention relates to the field of stimulus-responsive fluorescent anti-counterfeiting technology, and in particular to a stimulus-responsive dynamically adjustable multicolor luminescent eutectic gel, and a preparation method and application thereof. Background Art

[0002] Against the backdrop of escalating global data security threats and surging demand for commodity anti-counterfeiting, smart materials that can respond to chemical or physical stimuli have become a research hotspot in the field of materials informatics. However, existing material systems still have deficiencies in environmental tolerance, adhesion, and other aspects. These defects seriously restrict their industrial application process. Among the many anti-counterfeiting strategies, fluorescent materials stand out with their unique invisible coding characteristics. At the same time, they have the advantages of easy operation and high information confidentiality, making them a leader in the field of anti-counterfeiting technology. Among them, smart fluorescent gels provide new ideas for information encryption through a stimulus-responsive dynamic switching mechanism of luminescent colors. In recent years, researchers have been committed to applying hydrogels to explore modern information storage strategies. For example, Professor Chen Tao's team at the Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, developed an organic hydrogel system with fluorescence resonance energy transfer characteristics based on heterogeneous network structure design. By introducing H + The control strategy effectively inhibits the fluorescence transfer process, successfully realizes dynamic color control and improves anti-counterfeiting performance (.Le, X., Shang, H., Wu, S., Zhang, J., Liu, M., Zheng, Y., Chen, T. Heterogeneous fluorescent organohydrogelenables dynamic anti-counterfeiting[J]. Advanced Functional Materials, 2021, 31(52): 2108365.). Professor Qu Dahui's team at East China University of Science and Technology constructed a time-dependent fluorescent hydrogel system, whose "time lock" encryption mechanism realizes the time-effectiveness of information decryption, adding a time dimension constraint to the security protection system (Wang, Q., Qi, Z., Wang, QM, Chen, M., Lin, B., Qu, DHA time-dependent fluorescent hydrogel for "time-lock" information encryption[J]. Advanced Functional Materials, 2022, 32(49): 2208865.).

[0003] The above attempts provide new ideas for the development of gel-based information storage materials. Although substantial progress has been made, existing fluorescent gels still face challenges such as insufficient temperature resistance, poor solvent resistance, and insufficient adhesion stability on complex surfaces, which seriously restrict their practical applications. Especially in precision application scenarios such as anti-counterfeiting labels, the structural integrity and long-term stability of materials under cyclic mechanical stress have become key issues that determine their industrialization prospects. Future research needs to focus on key properties such as environmental tolerance optimization, adhesion enhancement, and dynamic response regulation to promote the evolution of fluorescent gel materials to the next generation of anti-counterfeiting systems with high environmental adaptability and strong adhesion. Summary of the Invention

[0004] The purpose of the present invention is to provide a stimulus-responsive dynamically adjustable multicolor luminescent eutectic gel and its preparation method and application, which has excellent environmental tolerance and interface adhesion.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for preparing a stimulus-responsive dynamically adjustable multicolor luminescent eutectic gel, comprising the following steps:

[0007] heating and mixing choline chloride and glycerol to obtain a eutectic solvent;

[0008] The eutectic solvent is mixed with N-hydroxymethyl acrylamide, 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and a fluorescent reagent, and a polymerization reaction is carried out under ultraviolet irradiation to obtain a eutectic gel;

[0009] The fluorescent reagent includes one or more of a blue fluorescent molecule, a red layered rare earth hydroxide, and a green layered rare earth hydroxide;

[0010] The structural formula of the blue fluorescent molecule HBopo is:

[0011]

[0012] The chemical composition of the red layered rare earth hydroxide is Eu(OH) 2.6 Cl 0.4 1.4H2O; the chemical composition of the green layered rare earth hydroxide is Tb(OH) 2.6 Cl 0.4 1.0H2O;

[0013] When the fluorescent reagent is a red layered rare earth hydroxide or a green layered rare earth hydroxide, the mixing further comprises adding 2,6-pyridinedicarboxylic acid.

[0014] Preferably, the molar ratio of choline chloride to glycerol is 0.5-1.5:1.

[0015] Preferably, the preparation method of the blue fluorescent molecule comprises the following steps:

[0016] Mixing methyl 2,5-dihydroxybenzoate, a first alcohol solvent, and hydrazine hydrate to perform a first reaction to obtain an intermediate product;

[0017] The intermediate product is mixed with o-phthalaldehyde and a second alcohol solvent, and after a second reaction, water is precipitated to obtain a blue fluorescent molecule.

[0018] Preferably, the molar ratio of methyl 2,5-dihydroxybenzoate to hydrazine hydrate is 0.5-1.5:1; the temperature of the first reaction is room temperature, and the time is 6-10 hours.

[0019] Preferably, the molar ratio of the intermediate product to o-phthalaldehyde is 0.5-1.5:1; the temperature of the second reaction is 60-100° C., and the time is 10-14 hours.

[0020] Preferably, the preparation method of the red layered rare earth hydroxide comprises the following steps:

[0021] Eu(NO3)3·6H2O, NaNO3 and water are mixed to obtain a mixed solution; a NaOH aqueous solution is used to adjust the pH value of the mixed solution to 5-7 to obtain a white suspension; Eu in the white suspension 3+ Concentration is 0.03~0.06mol·L -1 ;

[0022] The white suspension is reacted in a nitrogen atmosphere to obtain a red layered rare earth hydroxide; the reaction temperature is 60 to 80° C., and the reaction time is 12 to 24 hours.

[0023] Preferably, the preparation method of the green layered rare earth hydroxide comprises the following steps:

[0024] Tb(NO3)3·6H2O, NaNO3 and water are mixed to obtain a mixed solution; a NaOH aqueous solution is used to adjust the pH value of the mixed solution to 5-7 to obtain a white suspension; Tb in the white suspension 3+ Concentration is 0.03~0.06mol·L -1 ;

[0025] The white suspension is reacted in a nitrogen atmosphere to obtain a green layered rare earth hydroxide; the reaction temperature is 60 to 80° C., and the reaction time is 12 to 24 hours.

[0026] Preferably, when the fluorescent reagent is a red layered rare earth hydroxide or a green layered rare earth hydroxide, the mass ratio of the eutectic solvent, N-hydroxymethyl acrylamide, 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 2,6-pyridinedicarboxylic acid, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and the fluorescent reagent is 0.5-1.0:0.5-1.0:0.1-0.3:0.0025-0.0035:0.001-0.003:0.002-0.004;

[0027] When the fluorescent agent is a blue fluorescent molecule, the mass ratio of the eutectic solvent, N-hydroxymethyl acrylamide, 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and the fluorescent agent is 0.5-1.0:0.5-1.0:0.1-0.3:0.001-0.003:0.002-0.004;

[0028] The polymerization reaction temperature is room temperature, and the time is 20 to 60 minutes; the wavelength of the ultraviolet irradiation is 365 nm, and the power of the ultraviolet lamp used is 250W.

[0029] The present invention provides a stimulus-responsive, dynamically adjustable, multicolor luminescent eutectic gel prepared by the preparation method described in the above technical solution.

[0030] The present invention provides an application of the stimulus-responsive dynamically adjustable multicolor luminescent eutectic gel described in the above technical solution in the field of dynamic information encryption and decryption.

[0031] The present invention provides a method for preparing a stimulus-responsive, dynamically adjustable, multicolor luminescent eutectic gel. The main monomers are N-hydroxymethyl acrylamide (NMA) and zwitterionic monomer 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt (DMAPS). These monomers are dissolved in a eutectic solvent (DES). In the eutectic solvent, glycerol acts as a hydrogen bond donor and choline chloride acts as a hydrogen bond acceptor. The synergistic effect of the two effectively promotes the subsequent polymerization reaction, thereby constructing a dynamic cross-linked network. Under the synergistic effect of the two structural units in the eutectic gel (NMA can form a cross-linked system due to the hydroxyl groups of the side groups after polymerization, and DMAPS can copolymerize with NMA and exist as a structural unit on the polymer chain), the material not only has excellent mechanical strength, but also has good self-healing efficiency and outstanding shape plasticity. At the same time, the rich hydrogen bonds, π-π stacking, π-cation interactions, and ionic bonds within the material ensure its stable adhesion on a variety of material substrates. In addition, the low volatility of DES also makes the material have excellent environmental stability in practical applications. At the same time, by introducing the hydroxyl-modified blue light molecule HBopo into the anti-volatile DES solvent, Al 3+ Combined with the stimuli-responsive properties of the HBopo group and the stable luminescence of layered rare earth hydroxide nanosheets (LEuH / LTbHNSs), the material system successfully achieved red, green, and blue primary color luminescence and full spectrum tunability. This material is based on a biomimetic strategy to construct a new multifunctional eutectic gel material system, and through molecular design to achieve multifunctional integration of material properties, an Al2O3 with environmental adaptability and surface adaptive adhesion properties is obtained. 3+ The stimulus-responsive dynamically adjustable multicolor luminescent fluorescent eutectic gel has excellent environmental stability and dynamically adjustable multicolor luminescence properties (three fluorescent reagents (blue, red, and green) achieve multi-color adjustable colors), and has potential application value in the field of multi-level anti-counterfeiting science (information encryption and decryption).

[0032] The eutectic gel prepared by the present invention has a single Al 3+ Stimulus response color change performance, with a wide range of multi-color adjustability, stimulus response and self-adhesive comprehensive characteristics, is a kind of Al 3+ Multifunctional smart materials with excellent recognition, environmental adaptability and strong interface adhesion have potential application value in the field of dynamic information encryption and decryption.

[0033] The eutectic gel prepared by the present invention can achieve stable adhesion on a variety of heterogeneous substrates without the use of any adhesive, exhibiting excellent interface universality, and successfully realizing the characteristics of red, green and blue primary color luminescence and full spectrum tunability. This characteristic enables the material to construct complex patterns of dynamic coding on the surface of objects, providing technical reserves for multi-level anti-counterfeiting encryption materials.

[0034] The present invention combines the dynamic fluorescence coding characteristics of the material with the conformal deformation ability to construct a conformal deformation-chemical stimulation multi-level encryption verification gel, which has a simple preparation method and is easy to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Schematic diagram of the mechanical properties and environmental stability of different eutectic gels; a is the frequency rheological test of DB, DG, and DR from 0.1 rad / s to 100 rad / s; b is the temperature rheological test of DB, DG, and DR from 25°C to 80°C; c is the UV-visible transmittance of DB, DG, and DR; d is the tensile stress-strain curve of DB, DG, DR, and self-healing eutectic gel DB-GR, and the inset is the three-color self-healing eutectic gel; e is the Young's modulus and toughness of DB, DG, DR, and self-healing eutectic gel DB-GR; f is the weight retention rate of DB, DG, and DR stored at room temperature for 15 days.

[0036] Figure 2 Schematic diagram of the adhesion performance of DB eutectic gel; a is a photograph of DB eutectic gel adhered to different substrates; b is a schematic diagram of the lap shear test geometry and the bonding mechanism between the adhesive and the substrate; c is the adhesion strength of DB eutectic gel on different substrates; d is an image of DB eutectic gel tightly adhered to the balloon surface as the balloon volume changes; scale bar is 5 cm;

[0037] Figure 3 Schematic diagram of the information encryption application of DB eutectic gel; a is a schematic diagram of the process of inputting information to achieve encryption in a stretched DB eutectic gel; b is a comparison of visible light images of the DB eutectic gel in its original state and stretched state (stretching ratio of 200%); c is the corresponding luminescence image under 365nm ultraviolet light irradiation; d is the decoded information of the stretched DB eutectic gel barcode scanned by a smartphone;

[0038] Figure 4 Schematic diagram of the application of different eutectic gels in pharmaceutical anti-counterfeiting labels;

[0039] Figure 5 is the tunability of the luminescence color of DB'R, DB'G and DB'GR eutectic gels; a is the tunability of the luminescence color of DB'R eutectic gel at a concentration of 10 -9 ~10-2 M's Al 3+ Schematic diagram of light emission after exposure in solution (λ ex = 254, 365nm; eutectic gel block size: 0.8 × 0.8 × 0.1cm); b is the eutectic gel DB'G at a concentration of 10 -9 ~10 -2 Different Al 3+ Emission spectrum in solution (λ ex =290nm); c is the eutectic gel DB'GR at a concentration of 10 -9 ~10 -2 Different Al 3+ Emission spectrum in solution (λ ex =290nm); d is the 3+ CIE (1931) color coordinates (λ) of eutectic gels DB'R, DB'G and DB'GR with increasing concentrations ex =290nm).

[0040] Figure 6 is the morphology characterization diagram of DB, DG, and DR eutectic gel; a~c are SEM images of DB, DG, and DR eutectic gel; d~f are EDS mapping maps of DB, DG, and DR eutectic gel;

[0041] Figure 7 Compound HBopo in Example 1 1 HNMR spectrum. DETAILED DESCRIPTION

[0042] In the present invention, unless otherwise specified, the required raw materials or reagents are commercially available products well known to those skilled in the art.

[0043] The present invention provides a method for preparing a stimulus-responsive dynamically adjustable multicolor luminescent eutectic gel, comprising the following steps:

[0044] heating and mixing choline chloride and glycerol to obtain a eutectic solvent;

[0045] The eutectic solvent is mixed with N-hydroxymethyl acrylamide, 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and a fluorescent reagent, and a polymerization reaction is carried out under ultraviolet irradiation to obtain a eutectic gel;

[0046] The fluorescent reagent includes one or more of a blue fluorescent molecule (HBopo), a red layered rare earth hydroxide, and a green layered rare earth hydroxide;

[0047] The structural formula of the blue fluorescent molecule is:

[0048]

[0049] The chemical composition of the red layered rare earth hydroxide is Eu(OH) 2.6 Cl 0.4 1.4H2O; the chemical composition of the green layered rare earth hydroxide is Tb(OH) 2.6 Cl 0.4 1.0H2O;

[0050] When the fluorescent reagent is a red layered rare earth hydroxide or a green layered rare earth hydroxide, the mixing further comprises adding 2,6-pyridinedicarboxylic acid.

[0051] In the present invention, the molar ratio of choline chloride to glycerol is preferably 0.5-1.5:1, more preferably 0.5-1:1; the temperature of the heating and mixing is preferably 80-100°C, more preferably 85-95°C, and the time is preferably 0.5-2h, more preferably 1-1.5h.

[0052] In the present invention, the preparation method of the eutectic solvent is preferably: choline chloride is recrystallized in anhydrous ethanol and vacuum dried for 24 hours, glycerol is vacuum dried, the dried choline chloride and glycerol are mixed, placed in a three-necked flask, covered with a rubber stopper, mechanically stirred, and heated and mixed until a uniform colorless liquid is formed to obtain the eutectic solvent.

[0053] In the present invention, the preparation method of the blue fluorescent molecule preferably comprises the following steps:

[0054] Mixing methyl 2,5-dihydroxybenzoate, a first alcohol solvent, and hydrazine hydrate to perform a first reaction to obtain an intermediate product;

[0055] The intermediate product is mixed with o-phthalaldehyde and a second alcohol solvent, and after a second reaction, water is precipitated to obtain a blue fluorescent molecule.

[0056] In the present invention, the molar ratio of methyl 2,5-dihydroxybenzoate to hydrazine hydrate is preferably 0.5 to 1.5:1, more preferably 0.66 to 1:1.

[0057] In the present invention, the first alcohol solvent is preferably anhydrous ethanol; the present invention has no particular limitation on the amount of the anhydrous ethanol used, as long as the reaction proceeds smoothly.

[0058] In the present invention, the temperature of the first reaction is preferably room temperature, and the time is preferably 6 to 10 hours, more preferably 7 to 8 hours.

[0059] The present invention preferably carries out the first reaction under reflux + stirring conditions. After the reaction is completed, the reaction is cooled to room temperature, and a beige precipitate is precipitated. The precipitate is collected by filtration, washed with anhydrous ethanol and distilled water, and dried in vacuo. The resulting product is recrystallized from anhydrous ethanol to obtain an intermediate product, denoted as DHBH. The reaction is as follows:

[0060]

[0061] After obtaining the intermediate product, the present invention preferably dissolves the intermediate product in part of the second alcohol solvent to obtain a DHBH solution, dissolves o-phthalaldehyde in the remaining second alcohol solvent, and drops the obtained o-phthalaldehyde solution into the DHBH solution to perform a second reaction.

[0062] In the present invention, the molar ratio of the intermediate product to o-phthalaldehyde is preferably 0.5-1.5:1, more preferably 0.6-1.2:1, and further preferably 1:1; the second alcohol solvent is preferably ethanol; the present invention has no special limitation on the amount of the second alcohol solvent, as long as the reaction proceeds smoothly.

[0063] In the present invention, the temperature of the second reaction is preferably 60-100° C., more preferably 80-90° C., and the time is preferably 10-14 h, more preferably 12 h.

[0064] After the second reaction is completed, the solution is preferably cooled to room temperature and then subjected to rotary evaporation to remove volatile components to obtain a viscous liquid. Water is then added to the viscous liquid to precipitate pink particles, which are then collected by filtration, washed, and dried under vacuum to obtain a blue fluorescent molecule, designated HBopo. The amount of water used is not particularly limited and can be adjusted according to actual needs.

[0065] In the present invention, the preparation method of the red layered rare earth hydroxide preferably comprises the following steps:

[0066] Eu(NO3)3·6H2O, NaNO3 and water are mixed to obtain a mixed solution; a NaOH aqueous solution is used to adjust the pH value of the mixed solution to 5 to 7 (more preferably 5.5 to 6.9) to obtain a white suspension; Eu in the white suspension 3+ Concentration is 0.03~0.06mol·L -1 , more preferably 0.05 mol·L -1 ;

[0067] The white suspension is reacted in a nitrogen atmosphere to obtain a red layered rare earth hydroxide; the reaction temperature is preferably 60 to 80° C., more preferably 65 to 75° C., and the reaction time is preferably 12 to 24 hours.

[0068] In the present invention, the mass ratio of Eu(NO3)3·6H2O to NaNO3 is preferably 2.230:4.249.

[0069] In the present invention, the concentration of the NaOH aqueous solution is preferably 0.1 mol / L.

[0070] After the reaction was completed, the white particles were centrifuged, washed with water and dried under reduced pressure to obtain red layered rare earth hydroxide, which was recorded as LEuHs.

[0071] In the present invention, the preparation method of the green layered rare earth hydroxide preferably comprises the following steps:

[0072] Tb(NO3)3·6H2O, NaNO3 and water are mixed to obtain a mixed solution; a NaOH aqueous solution is used to adjust the pH value of the mixed solution to 5 to 7 (more preferably 5.5 to 6.9) to obtain a white suspension; Tb in the white suspension 3+ Concentration is 0.03~0.06mol·L -1 , more preferably 0.05 mol·L -1 ;

[0073] The white suspension is reacted in a nitrogen atmosphere to obtain a green layered rare earth hydroxide; the reaction temperature is 60 to 80° C., more preferably 65 to 75° C., and the reaction time is 12 to 24 hours.

[0074] In the present invention, the mass ratio of Tb(NO3)3·6H2O to NaNO3 is preferably 2.265:4.249; and the concentration of the NaOH aqueous solution is preferably 0.1 mol / L.

[0075] After the reaction was completed, the white particles were centrifuged, washed with water and dried under reduced pressure to obtain green layered rare earth hydroxide, which was recorded as LTbHs.

[0076] The present invention preferably disperses the red layered rare earth hydroxide or the green layered rare earth hydroxide in a glycine (Gly, 1.0 M) aqueous solution, and uses the obtained colloidal suspension to prepare a eutectic gel. The present invention has no particular limitation on the concentration of the colloidal suspension, which can be adjusted according to needs. In the embodiment of the present invention, it is specifically 10 mg·L -1 .

[0077] In the present invention, when the fluorescent reagent is a red layered rare earth hydroxide or a green layered rare earth hydroxide, the mass ratio of the eutectic solvent, N-hydroxymethyl acrylamide, 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 2,6-pyridinedicarboxylic acid, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and the fluorescent reagent is 0.5-1.0:0.5-1.0:0.1-0.3:0.0025-0.0035:0.001-0.003:0.002-0.004, more preferably 1.0:1.0:0.2:0.0032:0.002:0.002-0.004.

[0078] When the fluorescent reagent is a blue fluorescent molecule, the mass ratio of the eutectic solvent, N-hydroxymethyl acrylamide, 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and the fluorescent reagent is preferably 0.5-1.0:0.5-1.0:0.1-0.3:0.001-0.003:0.002-0.004, and more preferably 1.0:1.0:0.2:0.002:0.004.

[0079] The invention prepares a precursor solution obtained by mixing a eutectic solvent with N-hydroxymethyl acrylamide, 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 2,6-pyridinedicarboxylic acid (ligand), 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone (photoinitiator) and a fluorescent reagent. The mixture is polymerized in a self-made mold (a sandwich structure, i.e., a 1 mm thick hollow silicon wafer sandwiched between two glass plates) using an ultraviolet lamp to obtain a eutectic gel.

[0080] In the present invention, the polymerization reaction temperature is preferably room temperature, the time is preferably 20 to 60 minutes, more preferably 30 minutes; the wavelength of the ultraviolet irradiation is preferably 365 nm, and the power of the ultraviolet lamp used is preferably 250W.

[0081] The present invention provides a stimulus-responsive, dynamically adjustable, multicolor luminescent eutectic gel prepared by the preparation method described in the above technical solution.

[0082] The present invention changes the fluorescent color of the eutectic gel by varying the type of fluorescent reagent. When blue fluorescence is desired, the eutectic gel is prepared using a fluorescent reagent containing at least blue fluorescent molecules and then immersed in or sprayed with an aluminum ion solution, thereby achieving multi-color anti-counterfeiting. The present invention does not specifically limit the concentration and dosage of the aluminum ion solution; sufficient dosage is sufficient. A more preferred concentration of the aluminum ion solution is 0.01 M.

[0083] The present invention provides an application of the stimulus-responsive, dynamically adjustable, multicolor luminescent eutectic gel described in the above technical solution in the field of dynamic information encryption and decryption. The present invention does not specifically limit the method of application, and the application can be carried out according to methods well known in the art.

[0084] The specific embodiments of the present invention are described in detail below, but it should be understood that the scope of protection of the present invention is not limited by the specific embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. The experimental methods described in the embodiments of the present invention are all conventional methods unless otherwise specified.

[0085] The following experimental methods and detection methods, unless otherwise specified, are conventional methods; the following reagents and raw materials, unless otherwise specified, are commercially available.

[0086] Example 1

[0087] 1. Preparation of Fluorescent Functional Units

[0088] 1. Preparation of Al 3+ Stimulus-responsive blue fluorescent molecule HBopo:

[0089] (1) In a 250 mL three-necked flask, 80 mL of anhydrous ethanol and methyl 2,5-dihydroxybenzoate (3.36 g, 0.02 mol) were added, and then hydrazine hydrate (1.88 g, 0.03 mol) was added dropwise to obtain a clear solution. The resulting solution was stirred under reflux for 8 h. After cooling to room temperature, a beige precipitate was precipitated. The precipitate was collected by filtration, washed three times with anhydrous ethanol and distilled water, and dried in vacuo. The compound DHBH (2.68 g, 79.7% yield) was obtained as a beige powder by recrystallization from anhydrous ethanol. 1 HNMR(400MHz,DMSO-d6,ppm): δ11.56(s,1H),9.86(s,1H),8.99(s,1H),7.1 8(d,J=2.9,1H),6.83(dd,J=8.8,2.9,1H),6.72(d,J=8.8,1H),4.58(s,2H);

[0090] (2) In a 250 mL three-necked flask, DHBH (3.36 g, 0.02 mol) was dissolved in 30 mL of ethanol to obtain a DHBH solution; o-phthalaldehyde (2.68 g, 0.02 mol) was dissolved in 20 mL of ethanol and added dropwise to the DHBH solution. The resulting mixture was stirred at 80°C for 12 h, cooled to room temperature, and then the volatile components were removed by rotary evaporation to obtain a viscous liquid;

[0091] (3) 100 mL of deionized water was added to the viscous liquid to precipitate pink particles. The precipitate was collected by filtration, washed with water, and dried under vacuum to obtain a white powdery blue fluorescent molecule HBopo (3.69 g, yield 69.4%). 1 H NMR (400MHz, DMSO-d6, ppm): δ9.70(s,1H),7.86(s,1H),7.75–7.55(m,4H),7.33–7.24(m,1H),7.13–7.05(m,2H),7.01(s,1H). 13 CNMR (100MHz, DMSO-d6, ppm): δ160.07,153.65,149.02,140.40,132.62,127.63,127 .24,126.99,123.93,123.67,123.43,119.63,118.61,113.58,113.32,82.56,82.29( Figure 7 ).

[0092] 2. Preparation of red layered rare earth hydroxide LEuHs(Eu(OH) 2.6 Cl 0.4 1.4H2O):

[0093] LEuHs was synthesized according to literature reports (Wu, LY, Chen, GM, Li, ZBLayered rare-earthhydroxide / polyacrylamide nanocomposite hydrogels with highly tunablephotoluminescence. Small, 2017, 13(23): 1604070):

[0094] (1) Mix 2.230 g Eu(NO3)3·6H2O and 4.249 g NaNO3 in 85 mL deionized water to obtain Eu 3+ / Na + aqueous solution;

[0095] (2) Using a 0.1M NaOH aqueous solution to 3+ / Na + The pH of the solution was adjusted to 6.9 to obtain a white suspension in which Eu 3+ The concentration is 0.05 mol·L -1 ;

[0096] (3) The white suspension was placed in a nitrogen atmosphere and stirred at 75° C. overnight to obtain white particles; the white particles were centrifuged, washed with water, and dried under reduced pressure to obtain the product LEuHs as a white powder (0.94 g, yield 68.35%);

[0097] (4) LEuHs powder was ultrasonically dispersed in a glycine (Gly, 1.0 M) aqueous solution to obtain a concentration of 10 mg·L -1 LEuHs nanosheets (LEuHs-NSs) colloidal suspension.

[0098] 3. Preparation of green layered rare earth hydroxide LTbHs(Tb(OH) 2.6 Cl 0.4 1.0H2O):

[0099] (1) Mix 2.265 g of Tb(NO3)3·6H2O, 4.249 g of NaNO3 and 100 mL of deionized water to obtain Tb 3+ / Na + aqueous solution;

[0100] (2) Using a 0.1M NaOH aqueous solution to 3+ / Na + The pH value of the aqueous solution was adjusted to 6.9 to obtain a white suspension in which Tb 3+ The concentration is 0.05 mol·L -1 ;

[0101] (3) The white suspension was placed in a nitrogen atmosphere and stirred at 75° C. overnight to obtain white granules; the white granules were centrifuged, washed with water, and dried under reduced pressure to obtain the product LTbHs as a white powder (1.05 g, yield 74.48%);

[0102] (4) LTbHs powder was dispersed in a glycine (Gly, 1.0 M) aqueous solution and ultrasonicated to obtain a concentration of 10 mg·L -1 LTbHs nanosheets (LTbHs-NSs) colloidal suspension.

[0103] 2. Preparation of Monochrome Fluorescent Anti-counterfeiting Hydrogel

[0104] 1. Preparation of eutectic solvent (DES)

[0105] (1) Recrystallize choline chloride in anhydrous ethanol and vacuum dry for 24 hours; vacuum dry glycerol and set aside;

[0106] (2) Choline chloride and glycerol were mixed in a molar ratio of 1:2, placed in a three-necked flask at 95°C, covered with a rubber stopper, and mechanically stirred for 1 hour until a uniform colorless liquid was formed to obtain a eutectic solvent composed of choline chloride and glycerol; the product was stored in a vacuum desiccator filled with silica gel for later use.

[0107] 2. Al 3+ Preparation of Stimulus-Unresponsive Red Fluorescent Cocrystal Gel DR

[0108] A colloidal suspension (200 μL, 10 mg mL) of N-hydroxymethylacrylamide (NMA, 1.0 g), 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt (DMAPS, 0.20 g), 2,6-pyridinedicarboxylic acid (DPA, 3.2 mg), 2-hydroxy-4′-(2-hydroxyethoxy)-2-methylpropiophenone (I2959, 2.0 mg), and LEuHs NSs was added. -1 ) was mixed with 1.0 g of the above-mentioned eutectic solvent DES. After complete dissolution, the resulting precursor solution was poured into a homemade mold (sandwich structure, i.e., a 1 mm thick hollow silicon wafer was sandwiched between two glass plates) and polymerized under an ultraviolet lamp (250 W, 365 nm) for 30 min to obtain a transparent DR eutectic gel.

[0109] 3. Al 3+ Preparation of Stimulus-Unresponsive Green Fluorescent Cocrystal Gel DG

[0110] The method for preparing DR eutectic gel is the same as that in the above 2, except that the colloidal suspension of LEuHNSs is replaced by the colloidal suspension of LTbHNSs.

[0111] 4. Al 3+ Preparation of Stimulus-Responsive Blue Fluorescent Cocrystal Gel DB

[0112] (1) NMA (1.0 g), DMAPS (0.20 g), I2959 (2.0 mg) and HBopo DMSO solution (100 μL, 40 mg mL -1 ) was mixed with 1.0 g of the above-mentioned eutectic solvent DES; after complete dissolution, the resulting precursor solution was poured into a homemade mold and polymerized under a UV lamp (250 W, 365 nm) for 30 min to obtain a transparent DB' eutectic gel;

[0113] (2) The prepared DB' eutectic gel was completely immersed in 0.01MAl(NO3)3·9H2O aqueous solution for 1 min to form a blue fluorescent Al 3+ The gel of the complex was immersed in a large amount of deionized water to remove free Al 3+, and obtained eutectic gel DB (showing blue fluorescence).

[0114] 5. Al 3+ Preparation of Stimuli-responsive Dynamically Adjustable Multicolor Luminescent Cocrystal Gels

[0115] (1) According to the formulations in Table 1 below, DB'R, DB'G, and DB'GR eutectic gels were prepared respectively using the method of step (1) in the above 4.

[0116] Among them, DB'R is a eutectic gel of blue fluorescent molecule HBopo + red layered rare earth hydroxide, which shows red fluorescence like DR;

[0117] DB'G is a eutectic gel of blue fluorescent molecule HBopo + green layered rare earth hydroxide, which shows green fluorescence like DG;

[0118] DB'GR is a eutectic gel composed of blue fluorescent molecule HBopo + green + red layered rare earth hydroxides, showing an orange-yellow color.

[0119] Table 1 Formula for preparing fluorescent multicolor eutectic gel

[0120]

[0121] (2) The DB'R, DB'G, and DB'GR eutectic gels prepared according to Table 1 were cut into sizes of 0.8 × 0.8 × 0.1 cm and then completely immersed in 10 -9 ~10 -2 M Al(NO3)3·9H2O solution will form Al on the gel surface at room temperature. 3+ After 1 minute, the emission spectrum of the sample was recorded. The test spectrum was Figure 5 Medium ac, excitation wavelength λ ex =290nm.

[0122] When DB'R, DB'G, and DB'GR are immersed in aluminum ion solution, they all emit blue fluorescence, so these three gels can achieve dimming.

[0123] 6. Preparation of self-healing DB-GR eutectic gel

[0124] The prepared DR, DG and DB eutectic gels were cut into gel blocks of different shapes, which were aggregated together and self-healed at room temperature for 2 h to form a self-healing eutectic gel named DB-GR.

[0125] Performance Testing

[0126] 1) Figure 1Schematic diagram of the mechanical properties and environmental stability of different eutectic gels; a is the frequency rheological test of DB, DG, and DR from 0.1 rad / s to 100 rad / s (G' and G" correspond to the storage modulus and loss modulus of the gel, respectively); b is the temperature rheological test of DB, DG, and DR from 25°C to 80°C; c is the UV-visible transmittance of DB, DG, and DR; d is the tensile stress-strain curve of DB, DG, DR, and self-healing eutectic gel DB-GR, and the inset is the three-color self-healing eutectic gel; e is the Young's modulus and toughness of DB, DG, DR, and self-healing eutectic gel DB-GR; f is the weight retention rate of DB, DG, and DR after storage at room temperature for 15 days.

[0127] Figure 1 Figure a shows that the eutectic gel exhibits obvious viscoelasticity in the frequency range of 0.1 to 100 rad / s, and its storage modulus (G') is always higher than the loss modulus (G"), indicating that the material has a stable cross-linked network structure and excellent elastic behavior. This property ensures the structural integrity of flexible devices under repeated bending.

[0128] Figure 1 Medium-temperature rheological tests show that the eutectic gel maintains a stable, high elastic modulus within the temperature range of 25 to 80°C. This thermal stability is primarily attributed to a multi-level energy dissipation mechanism, synergistically constructed by strong hydrogen bonds and electrostatic interactions within the system. This temperature-insensitive property overcomes the limitation of traditional hydrogels, which are susceptible to softening at high temperatures, and expands their potential for application in extreme environments.

[0129] Figure 1 The optical transmittance test shows that the material has an average transmittance of over 90% in the visible light band (400-700nm), meeting the requirements for a transparent carrier for invisible anti-counterfeiting patterns.

[0130] Figure 1 The mechanical properties tests of Figures d and e show that the eutectic gel has high ductility (elongation at break > 300%), excellent toughness (> 90 kJ / m 3 ) and good Young's modulus (>65kPa), and the material achieved interface reconstruction within 2h at room temperature. The maximum strain of the repaired gel DB-GR after healing was 228.6%.

[0131] Figure 1 The experimental results in Figure f show that the weight loss of the eutectic gel is only 10% after being stored at room temperature (25°C) for 15 days.

[0132] The synergistic effect of the above properties indicates that the eutectic gel of the present invention exhibits great application potential in the fields of long-lasting anti-counterfeiting systems, flexible wearable devices, etc.

[0133] 2) Figure 2Schematic diagram of the adhesion performance of DB eutectic gel; a is a photograph of DB eutectic gel adhered to different substrates; b is a schematic diagram of the geometric structure of the lap shear test and the bonding mechanism between the adhesive and the substrate; c is the adhesion strength of DB eutectic gel on different substrates; d is an image of DB eutectic gel tightly adhered to the balloon surface as the balloon volume changes; scale bar is 5 cm.

[0134] like Figure 2 As shown in (a), the eutectic gel DB exhibits high adhesion strength on various substrate surfaces (including glass, iron (Fe), polyester (PET), polypropylene (PP), polystyrene (PS) and polytetrafluoroethylene (PTFE).

[0135] In order to further quantify its adhesion strength, a lap shear test was used for systematic testing: the gel was placed between two different substrate specimens for lap shear testing. The adhesion strength was measured using a high-precision electronic universal testing machine in shear mode. The dimensions of the adherend specimens were 25mm×5mm×1mm, the overlap area was 25mm*25mm, and the shear rate was 10mm / min. Adhesion strength definition: AS (kPa) = F (N) / A (cm 2 ), where F is the load of the bonded part at break (N), and A is the area of ​​the overlapped part (cm 2 )). The result is as follows Figure 2 As shown in Figure c, the adhesion strength of the DB eutectic gel on glass, Fe, PET, PP, PS, and PTFE substrates reached 67.97 kPa, 28.44 kPa, 54.39 kPa, 63.58 kPa, 36.69 kPa, and 29.59 kPa, respectively, fully demonstrating its wide applicability and stable adhesion performance. This wide range of adhesion performance is mainly attributed to the chemical / physical interaction mechanisms promoted by the abundant ion pairs and hydroxyl groups in its polymer network, including hydrogen bonds, electrostatic attraction, coordination bonds, and cation-π interactions ( Figure 2 In addition, the good tensile properties of the eutectic gel enable the material to fit closely to the surface of various complex-shaped substrates and undergo conformal deformation with them. Figure 2 As shown in (d), the eutectic gel adhered tightly to the balloon surface and did not delaminate even after 100 cycles of expansion and contraction. This result demonstrates its excellent surface-adaptive adhesion, making it an ideal choice for security labels and other applications requiring high-strength adhesion. This unique surface-adaptive adhesion property provides an important reference for the development of new anti-counterfeiting materials, flexible electronic devices, and biomedical materials, and has broad application prospects.

[0136] 3) Figure 3Schematic diagram of the information encryption application of DB eutectic gel; a is a schematic diagram of the process of inputting information to achieve encryption in the stretched state of DB eutectic gel; b is a comparison of visible light images of DB eutectic gel in the original state and stretched state (stretching ratio of 200%); c is the corresponding luminescent image under 365nm ultraviolet light irradiation; d is the decoded information of the DB eutectic gel barcode in the stretched state scanned by a smartphone.

[0137] The present invention covers a hollow barcode mask on the upper surface of the gel DB' and uses 0.01M Al 3+ The solution was coated on the surface of the eutectic gel DB' that was pre-stretched 200% and shielded by the mask, and the luminescence comparison between the gel shielded by the hollow barcode mask and the gel not shielded was observed. 3+ After coordinating with HBopo on the surface of the gel that is not blocked by the mask, the fluorescence of the gel in the unblocked area is significantly enhanced, forming a barcode with high contrast ( Figure 3 Under visible light, no information on the eutectic gel is visible in either the normal or stretched state ( Figure 3 (b). The barcode can only be displayed and recognized under UV light and in a stretched state ( Figure 3 c), double encryption is achieved. Furthermore, the encrypted information "infoA" can be unlocked by scanning with a smartphone ( Figure 3 (d) The system's dynamic encryption mechanism stems from the material's elastic deformation properties: upon removal of the external force, the gel spontaneously shrinks to its initial size, compressing the fluorescent pattern into an unrecognizable rectangular pattern, thus hiding information. Upon reapplying strain, the pattern returns to a macroscopically readable state.

[0138] 4) Using eutectic gel materials (DB'G, DB'R, DB'GR) with excellent adhesion and adjustable fluorescence properties, anti-counterfeiting labels containing the brand logo "LZU" were prepared through micro-engraving technology. The results are shown in Figure 4 .

[0139] Figure 4 Schematic diagram of the application of different eutectic gels in pharmaceutical anti-counterfeiting labels; the three splines L, Z, and U are formed by three gels DB'G, DB'R, and DB'GR, respectively. Figure 4 As shown, the label is in its initial state under visible light, and exhibits a basic fluorescent pattern after being excited by 254nm single-wavelength ultraviolet light; under dual-wavelength ultraviolet excitation of 254 and 365nm, the label can exhibit characteristic static fluorescent emission of green, red, and yellow; when exposed to Al 3+ When the solution is in solution, under the co-excitation of dual-wavelength ultraviolet light at 254nm and 365nm, the HBopo ligand in the gel matrix and the Al 3+Specific coordination occurs, driving a multi-color dynamic transformation in the "LZU" logo area: the fluorescence of the "L" region transitions from red to purple, the "Z" region from green to cyan, and the "U" region from yellow to white, thereby achieving a dynamic chemical response. This multi-dimensional anti-counterfeiting verification system, combining static optical features with dynamic chemical response, not only has high anti-counterfeiting recognition, but also provides an innovative solution for pharmaceutical product anti-counterfeiting through its excellent interfacial adhesion and environmental durability.

[0140] The present invention introduces two light-emitting units into the eutectic solvent: layered rare earth hydroxide nanosheets (LEuH NSs or LTbH NSs) that emit red or green light and Al 3+ The blue light-responsive molecule (HBopo) exhibits excellent full-spectrum tunability through precise control of the component ratio.

[0141] Figure 5 is the tunability of the luminescence color of DB'R, DB'G and DB'GR eutectic gels; a is the tunability of the luminescence color of DB'R eutectic gel at a concentration of 10 -9 ~10 -2 M's Al 3+ Schematic diagram of light emission after exposure in solution (λ ex = 254, 365nm; eutectic gel block size: 0.8 × 0.8 × 0.1cm); b is the eutectic gel DB'G at a concentration of 10 -9 ~10 -2 Different Al 3+ Emission spectrum in solution (λ ex =290nm); c is the eutectic gel DB'GR at a concentration of 10 -9 ~10 -2 Different Al 3+ Emission spectrum in solution (λ ex =290nm); d is the 3+ CIE (1931) color coordinates (λ) of eutectic gels DB'R, DB'G and DB'GR with increasing concentrations ex =290nm). Experimental results show that the DB'R, DB'G and DB'GR eutectic gels are immersed in different concentrations of Al 3+ In aqueous solution, the emission spectrum was effectively controlled. Figure 5 As shown in (a), the emission peak intensity of the DB'R system at 617 nm remains unchanged, while the emission peak intensity at 410 nm increases with the increase of Al 3+ The increase in concentration leads to a blue shift in the emission spectrum. Similar spectral change trends are verified in the DB'G and DB'GR systems ( Figure 5It is worth noting that the entire control process includes near-white light emission, whose CIE 1931 chromaticity coordinates are (0.30, 0.33), meeting the standard white light requirements ( Figure 5 (d)

[0142] Figure 6 is the morphology characterization diagram of DB, DG, and DR eutectic gel; a~c are SEM images of DB, DG, and DR eutectic gel; d~f are EDS mapping maps of DB, DG, and DR eutectic gel. Figure 6 It can be seen from the ac that the three eutectic gels all present a three-dimensional through-hole dense pore structure. This multi-pore system is Al 3+ Ion diffusion provides an effective mass transfer channel and confirms the successful construction of a cross-linked network based on dynamic hydrogen bonds and covalent interactions. The formation of a cross-linked structure plays a vital role in improving the mechanical strength, stability and ion exchange capacity of the eutectic gel. Further analysis of element distribution by EDS Mapping ( Figure 6 d) found: Al 3+ The ions are evenly distributed in the DB eutectic gel matrix. At the same time, the rare earth elements Tb(III) (DG system) and Eu(III) (DR system) are also evenly distributed in the gel matrix ( Figure 6 This further demonstrates the uniformity of the composite eutectic gel network structure and the uniformity of element distribution. These results confirm that the multi-scale cross-linked network constructed through specific intermolecular interactions can effectively regulate the spatial distribution and transport dynamics of functional ions.

[0143] In summary, the multicolor tunable fluorescent anti-counterfeiting eutectic gel prepared by the present invention exhibits excellent pleochroism. This property indicates that the multicolor tunable fluorescent anti-counterfeiting eutectic gel prepared by the present invention has potential application prospects in the practical anti-counterfeiting field (information encryption and decryption).

[0144] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for preparing a stimulus-responsive, dynamically adjustable, multicolor luminescent eutectic gel, characterized in that: The following steps are involved: heating and mixing choline chloride and glycerol to obtain a eutectic solvent; The eutectic solvent is mixed with N-hydroxymethyl acrylamide, 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and a fluorescent reagent, and a polymerization reaction is carried out under ultraviolet irradiation to obtain a eutectic gel; The fluorescent reagent includes one or more of a blue fluorescent molecule, a red layered rare earth hydroxide, and a green layered rare earth hydroxide; The structural formula of the blue fluorescent molecule is: The chemical composition of the red layered rare earth hydroxide is Eu(OH) 2.6 Cl 0.4 1.4H2O; the chemical composition of the green layered rare earth hydroxide is Tb(OH) 2.6 Cl 0.4 1.0H2O; When the fluorescent reagent is a red layered rare earth hydroxide or a green layered rare earth hydroxide, the mixing further comprises adding 2,6-pyridinedicarboxylic acid.

2. The preparation method according to claim 1, characterized in that The molar ratio of the choline chloride to the glycerol is 0.5-1.5:

1.

3. The preparation method according to claim 1, characterized in that The preparation method of the blue fluorescent molecule comprises the following steps: Mixing methyl 2,5-dihydroxybenzoate, a first alcohol solvent, and hydrazine hydrate to perform a first reaction to obtain an intermediate product; The intermediate product is mixed with o-phthalaldehyde and a second alcohol solvent, and after a second reaction, water is precipitated to obtain a blue fluorescent molecule.

4. The preparation method according to claim 3, characterized in that The molar ratio of the methyl 2,5-dihydroxybenzoate to the hydrazine hydrate is 0.5-1.5:1; the temperature of the first reaction is room temperature, and the time is 6-10 hours.

5. The preparation method according to claim 4, characterized in that The molar ratio of the intermediate product to o-phthalaldehyde is 0.5-1.5:1; the temperature of the second reaction is 60-100° C., and the time is 10-14 hours.

6. The preparation method according to claim 1, characterized in that The preparation method of the red layered rare earth hydroxide comprises the following steps: Eu(NO3)3·6H2O, NaNO3 and water are mixed to obtain a mixed solution; a NaOH aqueous solution is used to adjust the pH value of the mixed solution to 5-7 to obtain a white suspension; Eu in the white suspension 3+ Concentration is 0.03~0.06mol·L -1 ; The white suspension is reacted in a nitrogen atmosphere to obtain a red layered rare earth hydroxide; the reaction temperature is 60 to 80° C., and the reaction time is 12 to 24 hours.

7. The preparation method according to claim 1, characterized in that The preparation method of the green layered rare earth hydroxide comprises the following steps: Tb(NO3)3·6H2O, NaNO3 and water are mixed to obtain a mixed solution; a NaOH aqueous solution is used to adjust the pH value of the mixed solution to 5-7 to obtain a white suspension; Tb in the white suspension 3+ Concentration is 0.03~0.06mol·L -1 ; The white suspension is reacted in a nitrogen atmosphere to obtain a green layered rare earth hydroxide; the reaction temperature is 60 to 80° C., and the reaction time is 12 to 24 hours.

8. The preparation method according to claim 1, characterized in that When the fluorescent reagent is a red layered rare earth hydroxide or a green layered rare earth hydroxide, the mass ratio of the eutectic solvent, N-hydroxymethyl acrylamide, 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 2,6-pyridinedicarboxylic acid, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and the fluorescent reagent is 0.5-1.0:0.5-1.0:0.1-0.3:0.0025-0.0035:0.001-0.003:0.002-0.004; When the fluorescent agent is a blue fluorescent molecule, the mass ratio of the eutectic solvent, N-hydroxymethyl acrylamide, 3-[N,N-dimethyl-[2-(2-methylprop-2-enoyloxy)ethyl]ammonium]propane-1-sulfonic acid inner salt, 2-hydroxy-4'-(2-hydroxyethoxy)-2-methylpropiophenone and the fluorescent agent is 0.5-1.0:0.5-1.0:0.1-0.3:0.001-0.003:0.002-0.004; The polymerization reaction temperature is room temperature, and the time is 20 to 60 minutes; the wavelength of the ultraviolet irradiation is 365 nm, and the power of the ultraviolet lamp used is 250W.

9. The stimulus-responsive, dynamically adjustable, multi-color luminescent eutectic gel prepared by the preparation method according to any one of claims 1 to 8.

10. Application of the stimulus-responsive, dynamically adjustable, multi-color luminescent eutectic gel according to claim 9 in the field of dynamic information encryption and decryption.

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