A bright blind contrast information storage medium and application

Abstract

This invention belongs to the field of information storage materials technology and discloses a visual-blind comparative information storage medium and its application. This visual-blind comparative information storage medium is prepared by reacting a liquid crystal matrix (LCE) material with photochromic molecules and dynamic covalent bonds. This invention prepares a visual-blind comparative information storage medium with light-tunable fluorescence, thermally reconfigurable shape, and self-healing functions. Fluorescent information is reversibly written under the control of ultraviolet and visible light. By activating a dynamic covalent bond exchange reaction at high temperature, the shape of the fluorescent LCE film is programmed, and tactile Braille information is reversibly written. Combining visible fluorescent information with tactile Braille provides visual-blind comparative information that can be read by all users (including the visually impaired). Furthermore, utilizing the self-healing function of the fluorescent LCE film, free combination of information is achieved, eliminating the need for frequent mask replacements during information recording.

Description

Technical Field

[0001] This invention belongs to the field of information storage materials technology, and more specifically, relates to a sight-blind comparison information storage medium and its application. Background Technology

[0002] The development of information storage materials has played a crucial role in the progress of the information society, and exploring new multifunctional information storage materials is of great significance.

[0003] Currently, most reported information recording methods rely on the single stimulus response behavior of photochromic materials to record fluorescence information. However, this simple method is easily compromised and lacks security, and visual reading alone cannot fully meet the needs of all users. Furthermore, writing fluorescence information typically requires irradiating the photochromic material under a mask, and different masks are needed depending on the type of information to be stored, often requiring the customization of numerous masks, which presents inconvenience for recording fluorescence information in practical applications.

[0004] Currently, most research focuses on the storage and encryption of visual information, while exploration of touch displays such as Braille remains relatively scarce. Deformable materials with programmable shapes are excellent materials for fabricating Braille displays. Among many deformable materials, liquid crystal elastomers (LCEs) have attracted much attention due to their excellent mechanical properties and flexible deformability, and are widely used in sensing, actuation, display, and information protection fields.

[0005] Therefore, there is an urgent need to propose a new blind control information storage medium and its preparation method. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies by proposing a visual-blind comparative information storage medium and its application. The information storage medium of this invention is a fluorescent liquid crystal elastomer that combines light-tunable fluorescence and thermally reconfigurable shape, achieving dual information storage and display of visual fluorescence information and tactile Braille.

[0007] To achieve the above objectives, the first aspect of the present invention provides a light-blind comparison information storage medium, which is prepared by reacting a liquid crystal matrix with photochromic molecules and dynamic covalent bond molecules.

[0008] The fluorescent liquid crystal elastomer material developed in this invention, which combines stimulus-responsive fluorescence changes with shape programming, greatly enriches the forms of information storage and encryption. The flexible stimulus-responsive deformation of the fluorescent LCE with dynamic covalent bonds can be used to protect and supplement fluorescent information. The fluorescent information recorded by the medium of this invention is unaffected by tactile Braille information during reading, and the fluorescent information and tactile Braille information can be orthogonally combined in the fluorescent LCE.

[0009] According to the present invention, preferably, the blind comparison information storage medium is prepared by a liquid crystal matrix, photochromic molecules and dynamic covalent bond molecules through a chain extension reaction and a photopolymerization reaction under the conditions of a photoinitiator and a chain extender;

[0010] Alternatively, the light-blind comparison information storage medium is prepared by a liquid crystal matrix, photochromic molecules, and dynamic covalent bond molecules through chain extension and cross-linking reactions under cross-linking agent conditions.

[0011] In this invention, the photochromic molecule selected is one capable of reversibly switching between at least two isomers under irradiation with light of different wavelengths. It possesses advantages such as rich color characteristics, excellent mechanical stability, high safety (observable only under specific conditions), and remote controllability. According to this invention, preferably, the photochromic molecule is at least one selected from spiropyran, azobenzene derivatives, diarylethylene derivatives, and α-cyano-substituted diarylethylene derivatives.

[0012] Preferably, the photochromic molecule is an α-cyano-substituted diarylvinyl photochromic molecule; the α-cyano-substituted diarylvinyl photochromic molecule undergoes rapid and reversible Z / E isomerization under light irradiation, accompanied by a significant change in fluorescence intensity, thereby realizing the storage and display of fluorescence information.

[0013] More preferably, the structure of the α-cyano-substituted diarylvinyl photochromic molecule is as shown in general formula I, general formula II or general formula III; R in general formula I, general formula II and general formula III are each independently selected from general formula IV or general formula V, and m is an integer from 3 to 6;

[0014] Alternatively, the structure of the α-cyano-substituted diaryl vinyl photochromic molecule is as shown in general formula VI, general formula VII, or general formula VIII; R1 in general formula VI, general formula VII, or general formula VIII is independently selected from general formula IX or general formula X, and R2 in general formula VI, general formula VII, or general formula VIII is independently selected from general formula XI, general formula XII, general formula XIII, or general formula XIV, where m is an integer from 3 to 6;

[0015]

[0016] According to the present invention, preferably, the structure of the α-cyano-substituted diaryl vinyl photochromic molecule is selected from one of the following general formulas, where m is an integer from 3 to 6;

[0017]

[0018] According to the present invention, preferably, the liquid crystal substrate is an acrylate liquid crystal monomer.

[0019] In this invention, fluorescent liquid crystal elastomers (LCEs) combining dynamic covalent bonds with cross-linked polymers can utilize these dynamic covalent bonds to activate polymer network rearrangement, thereby generating various complex and reconfigurable geometries. The 3D shape configuration capabilities and excellent stability exhibited by LCEs with dynamic covalent bonds are beneficial for recording and stably storing Braille information.

[0020] According to the present invention, preferably, the dynamic covalent bond molecule undergoes a bond exchange reaction at high temperature, and the dynamic covalent bond molecule is selected from one of the following compounds, where n is an integer from 3 to 6;

[0021]

[0022] According to the present invention, preferably, the reaction of the liquid crystal matrix, photochromic molecules, and dynamic covalent molecules under the conditions of photoinitiator and chain extender includes:

[0023] S1: Mix and melt the liquid crystal matrix, photochromic molecules, dynamic covalent bond molecules and photoinitiator to obtain a first mixture;

[0024] S2: The chain extender is mixed with the first mixture to carry out a chain extension reaction to obtain a fluorescent liquid crystal oligomer;

[0025] S3: Stir and mix the fluorescent liquid crystal oligomer with an organic solvent to obtain a second mixture, and pour it into a mold to carry out a photopolymerization reaction to obtain the light-blind control information storage medium.

[0026] According to the present invention, preferably,

[0027] The molar ratio of photochromic molecules to liquid crystal matrix is ​​(0.01-1):10;

[0028] The molar ratio of the total amount of photochromic molecules and liquid crystal matrix to the dynamic covalent bond molecules is 10:(1-9);

[0029] The molar ratio of the total amount of photochromic molecules and liquid crystal matrix to the photoinitiator is 10:(0.01-1);

[0030] The molar ratio of the total amount of photochromic molecules and liquid crystal matrix to the chain extender is 10:(1-9);

[0031] The photoinitiator is benzoyl dimethyl ether;

[0032] The chain extender is selected from at least one of n-butylamine, n-pentylamine, n-hexylamine, 4-amino-1-butanol, 5-amino-1-pentanol, 6-amino-1-hexanol and 2,2-(1,2-ethylenedioxy)diethylthiol;

[0033] The organic solvent is selected from at least one of tetrahydrofuran, N,N-dimethylformamide, toluene, acetonitrile, chloroform, and dimethyl sulfoxide;

[0034] The melting temperature of the mixture is 90-150℃; the chain extension reaction temperature is 60-80℃; the light source used in the photopolymerization reaction has a wavelength of 360-370nm and a power of 1-5mW / cm². 2 The photopolymerization time is 30-120 min.

[0035] According to the present invention, preferably, the reaction of the liquid crystal matrix, photochromic molecules, and dynamic covalent bonds under crosslinking agent conditions includes:

[0036] (1) The liquid crystal matrix, photochromic molecules, dynamic covalent bond molecules and organic solvent are mixed and melted to obtain a molten mixture;

[0037] (2) Mix the crosslinking agent with the molten mixture evenly, pour it into a mold for chain extension reaction to obtain a fluorescent liquid crystal oligomer system; increase the reaction temperature of the system to carry out crosslinking polymerization reaction, and obtain the light-blind control information storage medium after curing;

[0038] According to the present invention, preferably,

[0039] The molar ratio of photochromic molecules to liquid crystal matrix is ​​(0.01-1):10;

[0040] The molar ratio of the total amount of photochromic molecules and liquid crystal matrix to the dynamic covalent bond molecules is 10:(1-9);

[0041] The molar ratio of the total amount of photochromic molecules and liquid crystal matrix to the crosslinking agent is 10:(1-9);

[0042] The crosslinking agent is selected from at least one of butanediamine, pentanediamine, and hexanediamine;

[0043] The organic solvent is selected from at least one of tetrahydrofuran, N,N-dimethylformamide, toluene, acetonitrile, chloroform, and dimethyl sulfoxide;

[0044] The mixing and melting temperature is 90-150℃, the chain extension reaction temperature is 60-80℃, and the crosslinking reaction temperature is 90-120℃.

[0045] According to the present invention, preferably, the light-blind comparison information storage medium is a membrane.

[0046] The second aspect of the present invention provides the application of the aforementioned sight-blind comparison information storage medium in the storage of sight-blind comparison information and in "movable type printing" style information storage.

[0047] According to the present invention, preferably, the visual-blindness comparison information storage medium is reversibly written with visual fluorescence information under ultraviolet and visible light irradiation, and reversibly written with tactile Braille information at high temperature; or,

[0048] The light-blind comparison information storage medium can be reversibly written with fluorescent information under ultraviolet and visible light irradiation. After being cut, fluorescent "movable type" is obtained. Under high temperature, the fluorescent "movable type" self-heals to achieve "movable type printing" type information storage.

[0049] In this invention, the specific steps of the preparation method of the α-cyano-substituted diaryl vinyl photochromic molecule with rapid reversible Z / E photoisomerization are as follows;

[0050] (1) In the presence of a first organic solvent, compound I and compound II are reacted to obtain compound III;

[0051] (2) In the presence of a second organic solvent, a first basic regulator and a first catalyst, compound III and compound IV are reacted to obtain compound V;

[0052] (3) In the presence of a second organic solvent, a first basic regulator and a first catalyst, 5-bromothiophene-2-carboxaldehyde and compound VI were reacted to obtain compound VII;

[0053] (4) In the presence of a third organic solvent and a second basic regulator, compound V and compound VII are reacted to obtain the α-cyanosubstituted diaryl vinyl photochromic molecule;

[0054] (5) In the presence of a fourth organic solvent, α-cyano-substituted diaryl vinyl photochromic molecules with non-polymerizable end groups are hydrogen-bonded together with C6M acid to obtain polymerizable α-cyano-substituted diaryl vinyl photochromic molecules.

[0055] The structural formula of compound I is as follows:

[0056]

[0057] The structural formula of compound II is:

[0058]

[0059] The structural formula of compound III is:

[0060]

[0061] The structural formula of compound IV is:

[0062] Where M is and One of them, where m is an integer between 3 and 6.

[0063] The structural formula of compound V is:

[0064] Where M is and One of them, where m is an integer between 3 and 6.

[0065] The structural formula of compound VI is:

[0066] Where N is One of them, where m is an integer between 3 and 6.

[0067] The structural formula of compound VII is:

[0068] Where N is One of them, where m is an integer between 3 and 6.

[0069] The beneficial effects of the technical solution of the present invention are as follows:

[0070] 1) Under 450 nm blue light irradiation, the fluorescence intensity of the fluorescent LCE thin film prepared by the method of this invention gradually decreases due to photoisomerization of fluorescent molecules. Under 365 nm ultraviolet light irradiation, the fluorescence intensity gradually recovers. This reversible fluorescence modulation can be repeated multiple times without significant attenuation. Utilizing the photomodulation of fluorescence properties of the fluorescent LCE thin film medium, multiple writing and erasing of encrypted fluorescent information is achieved. The written fluorescent information exhibits excellent stability and remains clearly visible even after being placed in the dark for several months.

[0071] 2) The fluorescent LCE thin film medium prepared by the method of the present invention undergoes a dynamic covalent bond exchange reaction at high temperature, and the shape of the film is repeatedly programmed, thereby writing information visible under sunlight and Braille at high temperature.

[0072] 3) The fluorescent LCE thin film prepared by the method of the present invention utilizes light-tunable fluorescence and thermally reconfigurable shape to reversibly write visual fluorescence information under ultraviolet and visible light irradiation and reversibly write tactile Braille information at high temperature. By orthogonally writing the fluorescence information and Braille on the fluorescent LCE thin film, information that can be read by everyone is obtained.

[0073] 4) The fluorescent LCE thin film medium prepared by this invention can reversibly write fluorescent information under ultraviolet and visible light irradiation. After cutting, fluorescent "type" is obtained. Under high temperature, the fluorescent "type" self-heals and can display new information.

[0074] 5) The fluorescent LCE thin film medium prepared by this invention differs from widely reported LCE materials. The preparation process of this fluorescent LCE thin film is simple and convenient, and its size is not limited by the liquid crystal cell, which is beneficial for storing a large amount of information. Compared with a single fluorescent information storage medium, this invention realizes the storage and display of both visual fluorescent information and Braille information in one storage medium, which can meet the needs of visually impaired people and related users. The information storage medium provided by this invention has a self-healing function, eliminating the need for frequent mask customization. The self-healing mechanism allows for the recombination of the written information "types" to achieve the display of new information. The visual-blind comparison information storage medium described in this invention can be reused multiple times, and the stored information has excellent stability.

[0075] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0076] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings, wherein the same reference numerals generally represent the same components in the exemplary embodiments of the invention.

[0077] Figure 1 A schematic diagram is shown of the photoisomerization process of the α-cyano-substituted diaryl vinyl photochromic molecule provided by the present invention under irradiation with 450 nm blue light and 365 nm ultraviolet light.

[0078] Figure 2 The fluorescence spectra of the blind control information storage medium of Embodiment 1 of the present invention are shown in the initial state, the steady state at 450 nm light, and the steady state at 365 nm light. Wherein, Normalized Intensity represents the normalized intensity; Initial represents the initial state; PSS... 450 Indicates steady state at 450nm light; PSS 365 This indicates the steady state of light at 365nm.

[0079] Figure 3 The thermal stress relaxation of the blind control information storage medium of Embodiment 1 of the present invention at different temperatures is illustrated. Here, G and G0 represent the initial modulus and instantaneous modulus of the blind control information storage medium, respectively, and Time represents time.

[0080] Figure 4 shows a schematic diagram (a) and a physical image (b) of the blind control information storage medium of Embodiment 1 of the present invention, which uses thermally reconstructed shape and optically tunable fluorescence to write all user-readable information. In the figures, Braille represents Braille; Blank FLCE film represents blank fluorescent LCE film medium; Fluorescence information represents fluorescence information; Erasing represents erasing; Writing represents writing; No information represents no information; and Information erasing represents information erasure.

[0081] Figure 5 shows a schematic diagram (a) and a physical image (b) of the blind control information storage medium of Embodiment 1 of the present invention, in which fluorescent information is written under irradiation with 450nm blue light, and the information is recombined into new information using self-healing properties. In the figures, Cut means trimming; Heal means healing; Daylight means sunlight; and UV light means ultraviolet light. Detailed Implementation

[0082] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the invention will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0083] Preparation Example 1

[0084] This preparation example provides a method for preparing an α-cyano-substituted diaryl vinyl photochromic molecule. The structure of the α-cyano-substituted diaryl vinyl photochromic molecule in this preparation example is shown in formula (1):

[0085]

[0086] The preparation method in this example includes the following steps:

[0087] (1) Dissolve 3.08 g of thiophene acetonitrile and 4.45 g of NBS in 125 mL of acetone and stir at room temperature for 6 h. After separation, remove the solvent by evaporation and purify by column chromatography to obtain bromothiophene acetonitrile.

[0088] (2) 1.54 g of 4-pyridineboronic acid pinacol ester, 1.82 g of bromothiophene acetonitrile, and 0.58 g of tetrakis(triphenylphosphine)palladium were dissolved in 100 mL of toluene. 30 mL of saturated Na2CO3 solution and 20 mL of n-propanol were added. The mixture was stirred and refluxed at 90 °C for 18 h under nitrogen protection. After separation, the solvent was evaporated, and the pyridinethiophene acetonitrile was purified by column chromatography.

[0089] (3) Dissolve 1.91 g of 5-bromothiophene-2-carboxaldehyde, 2.05 g of 4-pyridineboronic acid pinacol ester, and 0.58 g of tetrakis(triphenylphosphine)palladium in 100 mL of toluene, add 30 mL of saturated Na2CO3 solution and 20 mL of n-propanol. Under nitrogen protection, stir and reflux the mixture at 90 °C for 18 h. After separation, evaporate the solvent and purify by column chromatography to obtain pyridinethiophene aldehyde.

[0090] (4) Dissolve 1.5 g of pyridinethiophene acetonitrile and 1.42 g of pyridinethiophene aldehyde in 100 mL of ethanol. Slowly add 0.17 g of potassium tert-butoxide to the solution. The mixture is stirred and refluxed at 70 °C in the dark for 4 h. Add an appropriate amount of dilute hydrochloric acid to neutralize the pH of the mixture. After filtration, 2,3-bis(5-(pyridin-4-yl)thiophen-2-yl)acrylonitrile is purified by silica gel column chromatography.

[0091] (5) Dissolve 2,3-bis(5-(pyridin-4-yl)thiophen-2-yl)acrylonitrile and C6M acid in 50 mL of tetrahydrofuran at a molar ratio of 1:2. Stir the mixture at 60 °C in the dark for 30 min. Evaporate the solvent to obtain an α-cyano-substituted diaryl vinyl compound, formula (1).

[0092] Preparation Example 2

[0093] This preparation example provides a method for preparing an α-cyano-substituted diaryl vinyl photochromic molecule. The structure of the α-cyano-substituted diaryl vinyl photochromic molecule in this preparation example is shown in formula (2):

[0094]

[0095] The preparation method in this example includes the following steps:

[0096] (1) The synthesis of bromothiophene acetonitrile and pyridinethiophene aldehyde is the same as in Example 1.

[0097] (2) Place 2.19 g of 4-hydroxyphenylboronic acid pinacol ester, 4.14 g of anhydrous potassium carbonate, and 1.66 g of KI in a three-necked flask, and add 100 mL of 2-butanone to dissolve them. Under nitrogen protection, add 1.82 g of bromohexanol dropwise to the solution, and reflux and stir at 80 °C for 18 h. After separation, evaporate the solvent, and purify by column chromatography to obtain 6-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborane-2-yl)phenoxy)hex-1-ol.

[0098] (3) 2.02 g of bromothiophene acetonitrile, 3.2 g of 6-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborane-2-yl)phenoxy)hex-1-ol, and 0.58 g of tetra(triphenylphosphine)palladium were dissolved in 100 mL of toluene, and 30 mL of saturated Na2CO3 solution and 20 mL of n-propanol were added. The mixture was stirred and refluxed at 90 °C for 18 h under nitrogen protection. After extraction, the solvent was evaporated, and the product was purified by column chromatography to obtain 2-(5-(4-((6-hydroxyhexyl)oxy)phenyl)thiophene-2-yl)acetonitrile.

[0099] (4) Dissolve 3.15 g of 2-(5-(4-((6-hydroxyhexyl)oxy)phenyl)thiophen-2-yl)acetonitrile and 1.89 g of pyridinium thiophene aldehyde in 100 mL of ethanol, and slowly add 0.224 g of potassium tert-butoxide to the solution. Reflux the mixture at 70 °C in the dark and stir for 4 h. Add an appropriate amount of dilute hydrochloric acid to neutralize the pH of the mixture. After extraction, evaporate the solvent and purify by column chromatography to obtain 2-(5-(4-((6-hydroxyhexyl)oxy)phenyl)thiophen-2-yl)-3-(5-(pyridinium-4-yl)thiophen-2-yl)acrylonitrile.

[0100] (5) Dissolve 0.49 g of 2-(5-(4-((6-hydroxyhexyl)oxy)phenyl)thiophen-2-yl)-3-(5-(pyridin-4-yl)thiophen-2-yl)acrylonitrile in 20 mL of chloroform, cool to -5 °C, and add 0.2 g of triethylamine and 0.18 g of acryloyl chloride dropwise. Stir at room temperature in the dark for 12 h, and then add 40 mL of water to stop the reaction. After extraction, evaporate the solvent and purify by column chromatography to obtain the α-cyano-substituted diaryl vinyl compound, formula (2).

[0101] Preparation Example 3

[0102] This preparation example provides a method for preparing an α-cyano-substituted diaryl vinyl photochromic molecule. The structure of the α-cyano-substituted diaryl vinyl photochromic molecule described in this preparation example is shown in formula (3):

[0103]

[0104] The preparation method in this example includes the following steps:

[0105] (1) The synthesis of bromothiophene acetonitrile, 6-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborane-2-yl)phenoxy)hex-1-ol and 2-(5-(4-((6-hydroxyhexyl)oxy)phenyl)thiophene-2-yl)acetonitrile is the same as in Examples 1 and 2.

[0106] (2) 1.91 g of bromothiophenal, 3.2 g of 6-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborane-2-yl)phenoxy)hex-1-ol, and 0.58 g of tetra(triphenylphosphine)palladium were dissolved in 100 mL of toluene, and 30 mL of saturated Na2CO3 solution and 20 mL of n-propanol were added. The mixture was stirred and refluxed at 90 °C for 18 h under nitrogen protection. After extraction, the solvent was evaporated, and the product was purified by column chromatography to obtain 5-(4-((6-hydroxyhexyl)oxy)phenyl)thiophene-2-carboxaldehyde.

[0107] (3) Dissolve 3.15 g of 2-(5-(4-((6-hydroxyhexyl)oxy)phenyl)thiophen-2-yl)acetonitrile and 3.04 g of 5-(4-((6-hydroxyhexyl)oxy)phenyl)thiophen-2-carboxaldehyde in 100 mL of ethanol. Slowly add 0.224 g of potassium tert-butoxide to the mixture and reflux at 70 °C in the dark for 4 h. Add an appropriate amount of dilute hydrochloric acid to neutralize the pH of the mixture. After extraction, evaporate the solvent and purify by column chromatography to obtain 2,3-bis(5-(4-((6-hydroxyhexyl)oxy)phenyl)thiophen-2-yl)acrylonitrile.

[0108] (4) Dissolve 0.6 g of 2,3-bis(5-(4-((6-hydroxyhexyl)oxy)phenyl)thiophen-2-yl)acrylonitrile in 20 mL of chloroform, cool to -5 °C, and add 0.3 g of triethylamine and 0.27 g of acryloyl chloride dropwise. After stirring at room temperature in the dark for 12 h, add 40 mL of water to stop the reaction. After extraction, evaporate the solvent and purify by column chromatography to obtain the α-cyano-substituted diaryl vinyl compound, formula (3).

[0109] Preparation Example 4

[0110] This preparation example provides a method for preparing an α-cyano-substituted diaryl vinyl photochromic molecule. The structure of the α-cyano-substituted diaryl vinyl photochromic molecule in this preparation example is shown in formula (4):

[0111]

[0112] The preparation method in this example includes the following steps:

[0113] (1) The synthesis of bromothiophene acetonitrile and pyridinethiophene acetonitrile is the same as in Example 1.

[0114] (2) 1.91 g of 5-bromothiophene-2-carboxaldehyde, 2.04 g of (4,4,5,5-tetramethyl-1,3,2-dioxaborane-2-yl)benzene, and 0.58 g of tetra(triphenylphosphine)palladium were dissolved in 100 mL of toluene, and 30 mL of saturated Na2CO3 solution and 20 mL of n-propanol were added. The mixture was stirred and refluxed at 90 °C for 18 h under nitrogen protection. After extraction, the solvent was evaporated, and the phenylthiophene aldehyde was purified by column chromatography.

[0115] (4) Dissolve 2 g of pyridinethiophene acetonitrile and 1.88 g of phenylthiophene aldehyde in 100 mL of ethanol. Slowly add 0.112 g of potassium tert-butoxide to the solution. The mixture is stirred and refluxed at 70 °C in the dark for 4 h. Add an appropriate amount of dilute hydrochloric acid to neutralize the pH of the mixture. After extraction, evaporate the solvent and purify by column chromatography to obtain 3-(5-phenylthiophene-2-yl)-2-(5-(pyridin-4-yl)thiophene-2-yl)acrylonitrile.

[0116] (5) Dissolve 3-(5-phenylthiophen-2-yl)-2-(5-(pyridin-4-yl)thiophen-2-yl)acrylonitrile and C6M acid in 50 mL of tetrahydrofuran in a molar ratio of 1:1. Stir the mixture at 60 °C in the dark for 30 min. Evaporate the solvent to obtain the α-cyano-substituted diaryl vinyl compound, formula (4).

[0117] Example 1

[0118] This embodiment provides a method for preparing a blind control information storage medium, comprising the following steps:

[0119] S1: The liquid crystal matrix RM82 (also known as dynamic covalent bond molecular compound I), the α-cyano-substituted diaryl vinyl compound of Preparation Example 1 and the photoinitiator benzoyl dimethyl ether were placed in a 25 mL round bottom flask and melt-mixed at 100 °C to obtain the first mixture;

[0120] S2: The chain extender 4-amino-1-butanol was mixed with the first mixture, and the mixture was heated and stirred at 80°C for 24 hours to carry out the chain extension reaction, thereby obtaining the fluorescent liquid crystal oligomer.

[0121] in,

[0122] The molar ratio of photochromic molecules to the liquid crystal matrix RM82 is 0.02:10;

[0123] The total amount of photochromic molecules and liquid crystal matrix RM82 is in a molar ratio of 10:0.1 to the photoinitiator.

[0124] The total amount of photochromic molecules and liquid crystal matrix RM82 is in a molar ratio of 10:9 to the chain extender.

[0125] S3: The fluorescent liquid crystal oligomer is stirred and mixed evenly with tetrahydrofuran to obtain a second mixture, which is then poured into a quartz glass mold (the mold is assembled from two pieces of quartz glass separated by 500μm spacers). The mixture is then irradiated with 365nm ultraviolet light at room temperature for 30 minutes to carry out a photopolymerization reaction, thereby obtaining the light-blind comparison information storage medium, which is a fluorescent liquid crystal elastomer with light-tunable fluorescence and thermally reconfigurable shape.

[0126] The storage medium for the blindness control information obtained in this embodiment is used for the storage and display of the blindness control information:

[0127] In its initial state, a blank fluorescent LCE thin film medium containing no information emits bright green fluorescence. For example... Figure 1 and Figure 2 As shown, under 450 nm blue light irradiation, the fluorescence intensity of the fluorescent LCE thin film gradually decreases due to the photoisomerization of the α-cyano-substituted diaryl vinyl compound. Subsequently, under 365 nm ultraviolet light irradiation, the fluorescence of the film gradually recovers. By utilizing the photomodulation of the fluorescence properties of the fluorescent LCE thin film, encrypted fluorescent information can be reversibly written. Figure 3 As shown, under high temperature and the influence of a large number of tertiary amines, the transesterification reaction is activated, and the fluorescent LCE film can be programmed into various 3D shapes, thus realizing the writing of Braille information. As shown in Figure 4, Braille information was recorded by pressing the fluorescent LCE film medium in a mold at 150℃ for 10 minutes. Subsequently, the fluorescent LCE film was irradiated with 450nm blue light through a photomask, and the fluorescent information with the same meaning was also recorded on the fluorescent LCE film, realizing the storage and display of light-blind comparison information. This information showed excellent stability and remained clearly visible even after being placed in the dark for several months.

[0128] The sight-blind comparison information storage medium obtained in this embodiment is used for "movable type printing" style information storage and display:

[0129] The dynamic covalent exchange reaction activated at high temperature endows the fluorescent LCE film with self-healing properties. As shown in Figure 5, using the light-tunable fluorescence of the fluorescent LCE film, fluorescent information was written onto the film under 450nm blue light irradiation through a photomask. When further adjustments to the information are needed, there is no need to replace the photomask. After cutting the fluorescent LCE film and rearranging it as required, new fluorescent information was obtained after healing at 150℃ for 30 minutes.

[0130] Example 2

[0131] This embodiment provides a method for preparing a blind control information storage medium, comprising the following steps:

[0132] (1) The liquid crystal substrate RM82, the α-cyano-substituted diaryl vinyl compound of Preparation Example 2, (1,4-phenylenebis(1,3,2-dioxaborane-2,4-diyl)dimethylamine and DMF were mixed and melted at 100°C to obtain a molten mixture;

[0133] (2) Mix butanediamine with the molten mixture evenly, pour it into a mold, and carry out a chain extension reaction at 60°C for 1-2 hours to obtain a fluorescent liquid crystal oligomer system; heat to 90°C to carry out a crosslinking polymerization reaction, and obtain the light-blind control information storage medium after curing.

[0134] The molar ratio of photochromic molecules to liquid crystal matrix RM82 is 0.01:10.

[0135] The total amount of photochromic molecules and liquid crystal matrix RM82 is in a molar ratio of 10:4 to the dynamic covalent bond molecules;

[0136] The total amount of photochromic molecules and liquid crystal matrix RM82 is in a molar ratio of 10:5 to the crosslinking agent.

[0137] The storage medium for the blindness control information obtained in this embodiment is used for the storage and display of the blindness control information:

[0138] The specific operation of using the fluorescent LCE film for storing blind reference information is the same as in Example 1. The difference from Example 1 is that, compared to the transesterification reaction, the borate ester exchange reaction has a lower excitation temperature. When recording Braille information, the operating temperature is 80°C and the operating time is 5 hours.

[0139] The sight-blind comparison information storage medium obtained in this embodiment is used for "movable type printing" style information storage and display:

[0140] The specific operation of the fluorescent LCE film for "movable type" type information storage and display is the same as in Example 1. The difference from Example 1 is that the self-healing operation temperature is 80°C and the healing time is 8 hours.

[0141] Example 3

[0142] This embodiment provides a method for preparing a blind control information storage medium. The only difference between this embodiment and Embodiment 2 is that:

[0143] The α-cyano-substituted diaryl vinyl compound of Preparation Example 3 was selected;

[0144] The dynamic covalent bond molecule is dithiobis(hexane-6,1-diyl)diacrylate.

[0145] The storage medium for the blindness control information obtained in this embodiment is used for the storage and display of the blindness control information:

[0146] The specific operation of using the fluorescent LCE film for storing blind reference information is the same as in Example 1. The difference from Example 1 is that the excitation temperature of the diselenylene bond exchange reaction is above 60°C, and the operating temperature for recording Braille information is 70°C, with an operating time of 1 hour.

[0147] The sight-blind comparison information storage medium obtained in this embodiment is used for "movable type printing" style information storage and display:

[0148] The specific operation of the fluorescent LCE film for "movable type" type information storage and display is the same as in Example 1. The difference from Example 1 is that the self-healing operation temperature is 70°C and the healing time is 1 hour.

[0149] Example 4

[0150] This embodiment provides a method for preparing a blind control information storage medium, comprising the following steps:

[0151] S1: The liquid crystal substrate RM82, the α-cyano-substituted diaryl vinyl compound of Preparation Example 4, the carbamate compound, the photoinitiator benzoyl dimethyl ether and 0.5 g of tetrahydrofuran were placed in a 25 mL round-bottom flask and melt-mixed at 100 °C to obtain the first mixture;

[0152] S2: The chain extender 2,2-(1,2-ethylenedioxy)diethyl mercaptan was mixed with the first mixture and allowed to stand at room temperature for 24 hours to carry out the chain extension reaction, thereby obtaining the fluorescent liquid crystal oligomer.

[0153] in,

[0154] The molar ratio of photochromic molecules to the liquid crystal matrix RM82 is 0.02:10;

[0155] The total amount of photochromic molecules and liquid crystal matrix RM82 is in a molar ratio of 10:0.1 to the photoinitiator.

[0156] The total amount of photochromic molecules and liquid crystal matrix RM82 is in a molar ratio of 10:9 to the chain extender.

[0157] S3: Pour the fluorescent liquid crystal oligomer into a quartz glass mold (the mold is assembled from two pieces of quartz glass separated by a 500μm spacer), and irradiate it with 365nm ultraviolet light at room temperature for 30 minutes to carry out a photopolymerization reaction, thereby obtaining the light-blind comparison information storage medium, that is, a fluorescent liquid crystal elastomer with light-tunable fluorescence and thermally reconfigurable shape.

[0158] The storage medium for the blindness control information obtained in this embodiment is used for the storage and display of the blindness control information:

[0159] The specific operation of using fluorescent LCE films for storing information from light-blind controls is the same as in Example 1.

[0160] The sight-blind comparison information storage medium obtained in this embodiment is used for "movable type printing" style information storage and display:

[0161] The specific operation of using fluorescent LCE thin film for "movable type" type information storage and display is the same as in Example 1.

[0162] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A sight-blind comparison information storage medium, characterized in that, The blind comparison information storage medium is prepared by reacting a liquid crystal matrix with photochromic molecules and dynamic covalent molecules; The photochromic molecule is an α-cyano-substituted diaryl vinyl photochromic molecule, and the structure of the α-cyano-substituted diaryl vinyl photochromic molecule is selected from one of the following general formulas, where m is an integer from 3 to 6; 。 2. The sight-blind comparison information storage medium according to claim 1, wherein, The light-blind comparison information storage medium is prepared by a liquid crystal matrix, photochromic molecules and dynamic covalent bond molecules through chain extension reaction and photopolymerization reaction under the conditions of photoinitiator and chain extender; Alternatively, the light-blind comparison information storage medium is prepared by a liquid crystal matrix, photochromic molecules, and dynamic covalent bond molecules through chain extension and cross-linking reactions under cross-linking agent conditions.

3. The sight-blind comparison information storage medium according to claim 1 or 2, wherein, The liquid crystal substrate is an acrylate-based liquid crystal monomer; The dynamic covalent bond molecule is selected from one of the following compounds, where n is an integer from 3 to 6; 。 4. The sight-blind comparison information storage medium according to claim 2, wherein, The reactions of liquid crystal matrix, photochromic molecules, and dynamically covalently bonded molecules under photoinitiator and chain extender conditions include: S1: Mix and melt the liquid crystal matrix, photochromic molecules, dynamic covalent bond molecules and photoinitiator to obtain a first mixture; S2: The chain extender is mixed with the first mixture to carry out a chain extension reaction to obtain a fluorescent liquid crystal oligomer; S3: Stir and mix the fluorescent liquid crystal oligomer with an organic solvent to obtain a second mixture, and pour it into a mold to carry out a photopolymerization reaction to obtain the light-blind control information storage medium. in, The molar ratio of photochromic molecules to liquid crystal matrix is ​​(0.01-1):10; The molar ratio of the total amount of photochromic molecules and liquid crystal matrix to the dynamic covalent bond molecules is 10:(1-9). The molar ratio of the total amount of photochromic molecules and liquid crystal matrix to the photoinitiator is 10:(0.01-1). The molar ratio of the total amount of photochromic molecules and liquid crystal matrix to the chain extender is 10:(1-9). The photoinitiator is benzoyl dimethyl ether; The chain extender is selected from at least one of n-butylamine, n-pentylamine, n-hexylamine, 4-amino-1-butanol, 5-amino-1-pentanol, 6-amino-1-hexanol and 2,2-(1,2-ethylenedioxy)diethylthiol; The organic solvent is selected from at least one of tetrahydrofuran, N,N-dimethylformamide, toluene, acetonitrile, chloroform, and dimethyl sulfoxide; The melting temperature of the mixture is 90-150℃; the chain extension reaction temperature is 60-80℃; the light source used in the photopolymerization reaction has a wavelength of 360-370nm and a power of 1-5mW / cm². 2 The photopolymerization time is 30-120 min.

5. The sight-blind comparison information storage medium according to claim 2, wherein, The reactions of liquid crystal matrix, photochromic molecules, and dynamically covalently bonded molecules under crosslinking agent conditions include: (1) The liquid crystal matrix, photochromic molecules, dynamic covalent bond molecules and organic solvent are mixed and melted to obtain a molten mixture; (2) Mix the crosslinking agent with the molten mixture evenly, pour it into a mold to carry out the chain extension reaction, and obtain the fluorescent liquid crystal oligomer system; increase the reaction temperature of the system to carry out the crosslinking reaction, and obtain the light-blind control information storage medium after curing; in, The molar ratio of photochromic molecules to liquid crystal matrix is ​​(0.01-1):10; The molar ratio of the total amount of photochromic molecules and liquid crystal matrix to the dynamic covalent bond molecules is 10:(1-9). The total amount of photochromic molecules and liquid crystal matrix is ​​in a molar ratio of 10:(1-9) to crosslinking agent. The crosslinking agent is selected from at least one of butanediamine, pentanediamine, and hexanediamine; The organic solvent is selected from at least one of tetrahydrofuran, N,N-dimethylformamide, toluene, acetonitrile, chloroform, and dimethyl sulfoxide; The mixing and melting temperature is 90-150℃, the chain extension reaction temperature is 60-80℃, and the crosslinking reaction temperature is 90-120℃.

6. The sight-blind comparison information storage medium according to claim 1, wherein, The storage medium for the blind comparison information is a membrane.

7. The application of the sight-blind comparison information storage medium according to any one of claims 1-6 in the storage of sight-blind comparison information and in "movable type printing" type information storage.

8. The application according to claim 7, wherein, The visual-blind comparison information storage medium can reversibly write visual fluorescence information under ultraviolet and visible light irradiation, and reversibly write tactile Braille information at high temperature; or, The light-blind comparison information storage medium can be reversibly written with fluorescent information under ultraviolet and visible light irradiation. After being cut, fluorescent "movable type" is obtained. Under high temperature, the fluorescent "movable type" self-heals to achieve "movable type printing" type information storage.

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