A fibrous membrane and a method for its production and use

Abstract

The application discloses a kind of fiber membrane and its preparation method and application, the preparation raw material of the fiber membrane includes polymer and 3,4-dihydropyrimidine-2 (1H) -ketone, the structural formula of 3,4-dihydropyrimidine-2 (1H) -ketone is as follows: the fiber membrane of the present application has strong fluorescence, and it can present high contrast change before and after acid fumigation fluorescence color, and responds to acid and alkali rapidly, has wide application prospect in the field such as acid and alkali detection, environmental monitoring, anti-fake and textile detection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of fluorescent materials, in particular to a fiber membrane and a preparation method and application thereof. BACKGROUND

[0002] In the frontier field of chemistry and material science, fiber membrane materials have attracted extensive attention due to their excellent physical and chemical properties. Due to their unique structural characteristics, such as large specific surface area, high porosity, etc., these materials have shown wide application potential in many key fields such as filtration, separation, drug delivery and tissue engineering. Although traditional fiber membrane materials such as polypropylene and polytetrafluoroethylene have won the market's favor due to their excellent mechanical properties and chemical stability, their performance is still insufficient in some specific application scenarios such as chemical sensing and biological imaging. Therefore, in order to meet the growing demand for high-performance materials, it has become an urgent need in the industry to develop new fiber membrane materials with higher biological activity and specific functionality.

[0003] In the field of fluorescent probe research, tetraphenylethylene (TPE) compounds exhibit excellent fluorescence performance due to their unique aggregation-induced emission (AIE) characteristics. At the same time, 3,4-dihydropyrimidine-2(1H)-ketone (DHPM) compounds have wide application prospects in drug delivery and biocompatible materials due to their excellent biological activity and chemical stability. Considering the unique advantages of these two types of compounds, TPE-DHPM compounds formed by combining tetraphenylethylene and 3,4-dihydropyrimidine-2(1H)-ketone as fluorescent probes have shown great potential and research value.

[0004] However, in practical applications, the response speed of TPE-DHPM compounds as fluorescent probes has become a problem to be solved. Although TPE-DHPM compounds themselves have excellent fluorescence performance, due to the existence of intermolecular interaction and diffusion limitation, the contact efficiency between the fluorescent probe molecules and the measured substances (such as acid and base vapor) is low, which directly affects the response speed.

[0005] Therefore, if TPE-DHPM compounds can be prepared into fiber membranes, it is expected to solve the above problems. SUMMARY

[0006] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, the present application proposes a fiber membrane which not only can produce fluorescence, but also responds rapidly to stimuli such as acid and base.

[0007] The present application also proposes a preparation method of the above fiber membrane.

[0008] The present application also proposes the application of the above fiber membrane.

[0009] According to an aspect of the present application, a kind of fiber membrane is provided, and the preparation raw material of the fiber membrane includes polymer and tetraphenyl ethane-3, 4-dihydropyrimidine-2 (1H)-ketone compound, and the structural formula of the tetraphenyl ethane-3, 4-dihydropyrimidine-2 (1H)-ketone compound is as follows:

[0010]

[0011] According to a preferred embodiment of the present application, at least the following beneficial effects: the fiber membrane of the present application has excellent fluorescence performance, not only the fluorescence intensity is significantly, more can be in the change of acid-base environment, its fluorescence color produces significant contrast change in very short time.This characteristic makes the fiber membrane in the field of acid-base detection has very high sensitivity and accuracy.More remarkable is that the fiber membrane responds to acid-base environment extremely fast, can respond in 1 second, provides strong technical support for real-time monitoring and rapid judgment.Therefore, in the field of acid-base detection, environmental monitoring, anti-counterfeiting, textile detection and the industry control needing fast response, the fiber membrane of the present application all shows great potential application value, provides innovative solution for the development of related industry.

[0012] In some embodiments of the present application, the polymer includes at least one of cellulose acetate (CA), polystyrene (PS) and polylactic acid (PLA). The compound of the present application has good fluorescence stability in different polymer matrices.

[0013] In some embodiments of the present application, the mass ratio of the polymer to 3,4-dihydropyrimidine-2 (1H)-ketone is 1:0.01-0.1. For example, 1:0.05.

[0014] In some embodiments of the present application, the preparation raw material further includes a solvent, and the solvent is selected from a mixed solution of DMF (N,N-dimethylformamide) and DCM (dichloromethane).

[0015] In some embodiments of the present application, the volume ratio of DMF to DCM is 1:1-3. For example, 1:2.

[0016] In some embodiments of the present application, the mass ratio of 3,4-dihydropyrimidine-2 (1H)-ketone to solvent is 1:175-185. For example, 1:179, 1:180, etc.

[0017] In some embodiments of the present application, silicon oil paper is used as a grounding collector in the preparation process of the fiber membrane.

[0018] According to another aspect of the present application, a preparation method of the above fiber membrane is provided, including the following steps:

[0019] The tetraphenylstyrene-3,4-dihydropyrimidine-2(lH)-one compound and the polymer are weighed and dissolved in a solvent to prepare an electrospinning solution, the solution is loaded into a syringe, and the solution is extruded from a spinneret at a speed of 0.8-1.2 mL / h (preferably 1.0 mL / h) under the action of high-voltage static electricity to form fibers; wherein the spinning voltage is 15-20 kV (preferably 17 kV), and the working distance is 11-15 cm (preferably 13 cm).

[0020] The tetraphenylstyrene-3,4-dihydropyrimidine-2(lH)-one has the following structural formula:

[0021]

[0022] In some embodiments of the present application, a silicon oil paper is used as a grounding collector in the preparation of the fiber membrane.

[0023] According to another aspect of the present application, the above fiber membrane is applied in the field of detection or anti-counterfeiting.

[0024] In some embodiments of the present application, the detection includes at least one of the following detection contents:

[0025] 1) acidic substances;

[0026] 2) textile damage.

[0027] In some embodiments of the present application, the damage refers to damage caused by mechanics; preferably, the mechanics is mechanical force, more preferably including scratching and collision.

[0028] In some embodiments of the present application, the detection includes the following steps: applying the detection content to the fiber membrane, irradiating the compound by a UV light source as an excitation light source, and observing the fluorescence change.

[0029] In some embodiments of the present application, the detection content can be applied to the surface or the inside of the product to be detected without complex operations such as photopolymerization, the detection method of the present application is simple and convenient to operate, has high detection efficiency, can realize batch full-automatic detection, and has good industrial application prospect.

[0030] In some preferred embodiments of the present application, the application includes at least one of coating, dipping, and fumigation. The detection content is applied to the surface of the product to be detected by coating, dipping, or fumigation, and the operation is simple and convenient.

[0031] In some preferred embodiments of the present application, the wavelength of the UV light source is 320-405 nm; preferably 345-385 nm; more preferably 365 nm.

[0032] According to the application of the preferred embodiment, at least the following advantages are provided: the compound of the application has strong fluorescence, and after being prepared into a fiber membrane, the compound has a larger specific surface area, so that the response to external stimuli is faster. The fiber membrane of the application responds quickly to acid and alkali, and the response to acid fumigation can be as low as within 1s, which has good industrial application prospect.

[0033] According to another aspect of the application, a stress detection method is provided, comprising the following steps: attaching the fiber membrane to the surface and / or inside of the product to be detected, realizing the force-induced response by acting on the product to be detected by mechanical force, and observing the change of fluorescence intensity by irradiating the fiber membrane with an ultraviolet light source as an excitation light source to detect the change of stress.

[0034] According to another aspect of the application, the application of the fiber membrane in preparing toys, shape memory materials, impact-resistant protective materials, force sensor materials, mechanical probe materials is provided.

[0035] A material comprising the fiber membrane; wherein the material can be used to prepare at least one of the following products:

[0036] 1) toys;

[0037] 2) shape memory materials;

[0038] 3) impact-resistant protective materials;

[0039] 4) force sensor materials;

[0040] 5) mechanical probe materials;

[0041] 6) optical switch materials;

[0042] 7) anti-counterfeiting materials;

[0043] 8) flexible electronic products;

[0044] 9) intelligent packaging materials.

[0045] Other features and advantages of the present application will be set forth in the description that follows, and in part will become apparent to those skilled in the art upon examination of the following or can be learned by practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0046] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the following description, taken in conjunction with the accompanying drawings, in which:

[0047] Figure 1 Figure 1 is a SEM image of the nanofiber membrane prepared in Example 1 of the present application: a) 5.0kX magnification; b) 10.0kX magnification.

[0048] Figure 2 are the daylight lamp photos a), the ultraviolet lamp photos b), and the inverted fluorescence microscope photos c) of the PLA-TPE-DHPM micro-nano fiber membrane prepared in Example 1 of the present application; the daylight lamp photos d), the ultraviolet lamp photos e), and the inverted fluorescence microscope photos f) of the PS-TPE-DHPM micro-nano fiber membrane prepared in Example 3 of the present application.

[0049] Figure 3 are the PL spectra and fluorescence photos of the PLA-TPE-DHPM micro-nano fiber membrane prepared in Example of the present application under external stimulation.

[0050] Figure 4 are the "AIE" pattern a) drawn by the powder of the TPE-DHPM compound in the comparative example of the present application, and the photo b) of the PLA-TPE-DHPM micro-nano fiber membrane under external stimulation. The photo is taken under the ultraviolet irradiation of 365 nm. DETAILED DESCRIPTION

[0051] The concept and the technical effects of the present application will be described clearly and completely in combination with the examples, so as to fully understand the purpose, features and effects of the present application. Obviously, the described examples are only some of the examples of the present application, but not all the examples. Based on the examples of the present application, other examples obtained by those skilled in the art without creative labor are within the protection scope of the present application. The test methods used in the examples are conventional methods, and the materials and reagents used are commercially available, unless otherwise specified. The same parameters are used in the same way in each example, unless otherwise specified. The examples described below are exemplary and are used to explain the present application, and cannot be understood as limiting the present application.

[0052] In the description of the present application, the description of the terms "one embodiment", "some embodiments", "exemplary embodiment", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in combination with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the exemplary description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0053] Some of the raw materials used in the following examples and comparative examples are shown in Table 1 below:

[0054] Table 1

[0055]

[0056] The instruments used in the following examples and comparative examples are shown in Table 2 below:

[0057] Table 2

[0058]

[0059]

[0060] The methods and main parameter information used in the test characterization process are as follows:

[0061] Compound 1 H-NMR and 13 C-NMR were measured on a Bruker AVANCE NEO 500 spectrometer with deuterated chloroform as the solvent, tetramethylsilane (TMS) as the internal standard, to test the chemical structure of the compound.

[0062] Fluorescence spectra and ultraviolet-visible absorption spectra were used to analyze the photophysical properties of the compound. The excitation and emission slits of the fluorescence spectrum for AIE performance test were 10 nm and 15 nm, and the rest were 3 nm and 5 nm.

[0063] X-ray diffractometer with Cu Kα (λ = 0.1541 nm) as the light source, test voltage 40 kV, 40 mA, used to characterize the aggregate structure of the compound.

[0064] Steady-state / transient combined fluorescence spectrometer and calibrated integrating sphere tested the fluorescence quantum efficiency of the compound.

[0065] Scanning electron microscope was used to observe the microstructure of the fiber membrane, and the operating voltage was 15 kV.

[0066] TPEA can be self-made (referring to the literature Iminoboronate-based peptide cyclization that responds to pH, oxidation, and small molecule modulators [J]. Journal of the American Chemical Society, 2016, 138 (7): 2098-2101. Preparation) or purchased from the market with cas number 1289218-74-1.

[0067] To the prepared three-necked flask, 20 mL THF was added under nitrogen atmosphere. The mixture was heated to 90 °C until the starting material was dissolved. 0.5 mmol TBAB and 18 mL aqueous solution containing 0.036 mol potassium carbonate were added and the mixture in the three-necked flask was stirred for 30 min. Then Pd(PPh3)4(0.12 g, 0.1 mmol) was added. The reaction was followed by thin layer chromatography until the starting material disappeared. After cooling to room temperature, the reaction solution in the prepared three-necked flask was mixed with a mixture solution of water and ethyl acetate (1 :3) and extracted three times, and the organic solution was collected. After drying with anhydrous sodium sulfate, the solid product was obtained by a rotary evaporator. The crude product was purified by silica gel chromatography column with a mixture solution of DCM and n-hexane (1 :2) to obtain the pure solid product TPEA (3.23 g, yield 89%).

[0068]

[0069] The prepared product was mixed and used for the preparation of the product of the following examples.

[0070] The preparation process of TPE-DHPM is as follows:

[0071] TPEA (0.50 g, 1.38 mmol) was added to 30 mL anhydrous ethanol and heated and stirred. After TPEA was fully dissolved, anhydrous magnesium chloride (0.015 g, 0.138 mmol) and catalyst glacial acetic acid (9 mL, 30% of ethanol) were added, and the stirring was continued at 78 °C for 10 min. Urea (0.13 g, 2.08 mmol) and acetylacetone (0.138 g, 1.38 mmol) were added to the three-necked flask, and the reaction was continued for 24 h. After filtration, the filter residue was washed with ethanol repeatedly three times to obtain white powder (0.4 g, 80%).

[0072] 1 H NMR (500 MHz, Chloroform-d) δ 8.01 (s, 1H), 7.14 - 6.94 (m, 18H), 5.58 (d, J = 2.5 Hz, 1H), 5.32 (d, J = 2.8 Hz, 1H), 2.32 (s, 3H), 2.03 (s, 3H). 13 C NMR (151 MHz,) δ 194.35, 151.93, 148.13, 143.11, 142.23, 140.61, 140.24, 130.77, 130.61, 127.84, 127.79, 126.60, 126.51, 126.04, 109.13, 53.60, 30.11, 19.65.

[0073] Example 1

[0074] A fiber membrane was prepared in this example. 0.05 g of tetraphenylethylene-3,4-dihydropyrimidine-2(1H)-one TPE-DHPM prepared in the above operation, 1 g of polymer (PLA) were dissolved in 8.95 g of a mixed solution of DMF / DCM (v / v=1 / 2) to prepare an electrospinning solution. Then, the solution was loaded into a 10 mL syringe, and the spinneret was extruded at a speed of 1 mL / h to form fibers under the action of high-voltage static electricity. The spinning voltage was 17 kV, the working distance was 13 cm, and a silicone oil paper was used as a grounded collector.

[0075] Example 2

[0076] A fiber membrane was prepared in this example. 0.05 g of tetraphenylethylene-3,4-dihydropyrimidine-2(1H)-one TPE-DHPM prepared in the above operation, 1 g of polymer (CA) were dissolved in 8.95 g of a mixed solution of DMF / DCM (v / v=1 / 2) to prepare an electrospinning solution. Then, the solution was loaded into a 10 mL syringe, and the spinneret was extruded at a speed of 1 mL / h to form fibers under the action of high-voltage static electricity. The spinning voltage was 17 kV, the working distance was 13 cm, and a silicone oil paper was used as a grounded collector.

[0077] Example 3

[0078] A fiber membrane was prepared in this example. 0.05 g of tetraphenylethylene-3,4-dihydropyrimidine-2(1H)-one TPE-DHPM prepared in the above operation, 1 g of polymer (polystyrene (PS)) were dissolved in 8.95 g of a mixed solution of DMF / DCM (v / v=1 / 2) to prepare an electrospinning solution. Then, the solution was loaded into a 10 mL syringe, and the spinneret was extruded at a speed of 1 mL / h to form fibers under the action of high-voltage static electricity. The spinning voltage was 17 kV, the working distance was 13 cm, and a silicone oil paper was used as a grounded collector.

[0079] Comparative Example

[0080] A fluorescent material was provided in this example, which was 0.05 g of 3,4-dihydropyrimidine-2(1H)-one TPE-DHPM prepared in the above operation.

[0081] Test Example

[0082] The acid-base stimulus response performance of the fiber membrane prepared in the example and the fluorescent material of the comparative example was tested in this test example. The specific operation was as follows:

[0083] The samples of the examples and comparative examples were subjected to treatment by acid vapor (HCI) and base vapor (NH3) fumigation under the same conditions to test their response time and fluorescence change. Since HCI and NH3 are both volatile, a small amount of acid or base solution was present in a closed container at room temperature (25°C) and the container was filled with acid or base vapor after a period of time. A period of time was allowed to pass to allow the sample to be fully protonated or deprotonated. At 25°C, a small amount of hydrochloric acid solution or ammonia water was placed in a closed desiccator (hydrochloric acid aqueous solution was used, with HCI content of 36% to 38%; base solution used ammonia water, with NH3 content of 25% to 28%. 10 to 15 ml of hydrochloric acid or ammonia water solution was placed in a desiccator of about 6.28 liters, and the container was filled with acid or base vapor at room temperature (about 25°C) for about 30 minutes), after the acid vapor and ammonia vapor filled the desiccator, the sample was placed in a petri dish and placed in the desiccator, a 365 nm UV lamp was used to observe the fluorescence change, and the response time was recorded.

[0084] It was found that the TPE-DHPM compound required a relatively long time to test the acid-base stimulation in powder state, because the acid vapor first contacted the outermost layer of the powder, and it took time to diffuse to the inner layer. After the initial powder of TPE-DHPM was fumigated by hydrochloric acid vapor, the fluorescence color changed obviously: from the initial light blue fluorescence to dark blue fluorescence, and the emission wavelength also changed from the initial 474 nm to 456 nm, which indicated that the solid powder of TPE-DHPM had obvious acid stimulation response. Subsequently, the sample was fumigated by ammonia vapor and returned to the initial state. After the powder was ground thoroughly, the fluorescence color changed from green to yellow after fumigation by hydrochloric acid vapor under UV irradiation (~ 4 s), and the yellow fluorescence gradually faded to the original green color in the dark environment after the UV light was turned off for several hours. No photochromic phenomenon was observed for the pristine powder after fumigation by hydrochloric acid vapor.

[0085] The results of the electron microscopy characterization of the PLA-TPE-DHPM fiber membrane are shown in Figure 1 As can be seen from the figure, the surface of the prepared composite fiber membrane is uniform and smooth, and no granular aggregates are observed, indicating that the TPE-DHPM compound has good compatibility with PLA, and the addition of the TPE-DHPM compound does not affect the spinning performance of PLA. At the same time, the TPE-DHPM compound was compounded with PS to prepare a micro-nano fiber membrane to explore the fluorescence stability of the TPE-DHPM compound in different polymers, and it was found that it had good fluorescence stability.

[0086] As shown in Figure 2As shown, the PLA-TPE-DHPM micro-nanofiber membrane and the PS-TPE-DHPM micro-nanofiber membrane emit blue fluorescence under a 365 nm ultraviolet lamp, and it can be seen from the inverted fluorescence microscope photos that the TPE-DHPM compound is uniformly dispersed in the PS and PLA polymers. The results show that the TPE-DHPM compound has good fluorescence stability in different polymers.

[0087] During the acid stimulus response experiment, after the PLA-TPE-DHPM micro-nanofiber membrane was fumigated with hydrochloric acid vapor for a period of time and irradiated with UV light for about 1 s, the fluorescence color changed from light blue to yellow, and the maximum emission wavelength of the fluorescence also red-shifted from 469 nm to 565 nm, with a red shift of 96 nm (as shown in Figure 3 The photochromic time of the micro-nanofiber membrane after UV light irradiation and HCl fumigation was shortened from 4 s in the grinding state of the compound in Comparative Example 1 to 1 s, mainly because the micro-nanofiber membrane has high porosity and large specific surface area, and during the HCl vapor fumigation process, more HCl vapor interacts with the TPE-DHPM molecules, thereby making the photoresponse time faster.

[0088] The effects of other embodiments are similar to those of Embodiment 1, and to avoid redundancy, they are not shown one by one.

[0089] Based on the photochromic properties of the TPE-DHPM compound after HCl vapor fumigation, it is shown that it has great application potential as an optical recording material. To verify its potential applications, the following tests were conducted:

[0090] First, the Pristine powder was evenly smeared on the weighing paper, and then the "AIE" word was written on the paper to prepare the initial prototype. After HCl vapor fumigation, the AIE word was irradiated with a UV lamp, and the fluorescence color gradually changed from light green to yellow emission (as shown in Figure 4 Due to the powder being in an amorphous state, the photochromic properties will only be exhibited after HCl vapor fumigation. The PLA-TPE-DHPM micro-nanofiber membrane was prepared by electrospinning technology and a "pen" pattern was made, as shown in Figure 4 After HCl vapor fumigation, the "pen head" irradiated with a UV lamp showed yellow fluorescence emission, while the "pen shaft" not irradiated with a UV lamp had the same initial fluorescence color. This high-sensitivity HCl vapor-induced photochromic performance has great application prospects in anti-counterfeiting and textile detection.

[0091] In summary, the present invention's composite of TPE-DHPM with polymers such as polylactic acid to prepare PLA-TPE-DHPM micro-nanofiber membranes improves acid response and imparts photochromic properties upon acid fumigation. Studies have shown that the photochromic properties are primarily caused by the photocyclic reaction of the TPE-DHPM compound.

[0092] The embodiments of the present invention are described in detail above, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge scope of ordinary technicians in the relevant technical field without departing from the scope of the present invention.

Claims

1. A fibrous membrane characterized by: The preparation raw material of the fiber film comprises a polymer and a tetraphenylstyrene-3,4-dihydropyrimidine-2(1H)-one compound, and the structural formula of the tetraphenylstyrene-3,4-dihydropyrimidine-2(1H)-one compound is as follows: ； The polymer comprises at least one of cellulose acetate, polystyrene and polylactic acid; and the mass ratio of the polymer to 3,4-dihydropyrimidine-2(1H)-one is 1:0.01-0.

1.

2. The fibrous membrane according to claim 1, characterized in that: The preparation raw material further comprises a solvent, and the solvent is selected from a mixed solution of DMF and DCM.

3. The fibrous membrane according to claim 2, characterized in that: The volume ratio of the DMF to DCM is 1:1-3.

4. A method for producing a fibrous membrane, characterized by: The method comprises the following steps: The tetraphenylstyrene-3,4-dihydropyrimidine-2(1H)-one compound and the polymer are weighed and dissolved in a solvent to prepare an electrospinning solution, the solution is loaded into a syringe, and the solution is extruded from a spinneret at a speed of 0.8-1.2 mL / h to form a fiber under the action of high-voltage electrostatic field; wherein the spinning voltage is 15-20 kV, and the working distance is 11-15 cm; the polymer comprises at least one of cellulose acetate, polystyrene and polylactic acid; and the mass ratio of the polymer to 3,4-dihydropyrimidine-2(1H)-one is 1:0.01-0.

1. The structural formula of the tetraphenylstyrene-3,4-dihydropyrimidine-2(1H)-one is as follows: 。 5. Application of the fiber film according to any one of claims 1-3 in the field of detection or anti-counterfeiting.

6. Use according to claim 5, characterized in that: The detection comprises at least one of the following detection contents: 1) acidic substances; 2) textile damage.

7. A stress detection method characterized by: The method comprises the following steps: attaching the fiber film according to any one of claims 1-3 to the surface and / or interior of a product to be detected, realizing a force-induced response by acting on the product to be detected by mechanical force, and observing the change in fluorescence intensity by irradiating the fiber film with an ultraviolet light source as an excitation light source to detect the stress change.

8. Application of the fiber film according to any one of claims 1-3 in the preparation of toys, shape memory materials, impact-resistant protective materials, force sensor materials, mechanical probe materials.

9. A material characterized in that: The material comprises the fiber film according to any one of claims 1-3; and the material can be used to prepare at least one of the following products: 1) toys; 2) shape memory materials; 3) impact-resistant protective materials; 4) force sensor materials; 5) mechanical probe materials; 6) optical switch materials; 7) anti-counterfeiting materials; 8) flexible electronic products; 9) intelligent packaging materials.

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