Quinoline group modified aromatic compound as well as preparation method and application thereof in pH response type fiber membrane

Abstract

The invention discloses a quinoline group modified aromatic compound as well as a preparation method and application thereof in a pH response type fiber membrane. The compound has the following structural formula: # imgabs0 #, wherein R is selected from quinolyl. The compound of the scheme structure has a unique molecular structure, and the quinoline group structure has diversity and flexibility, so that the compound of the scheme structure is flexible in structural design, excellent in fluorescence performance and good in structural stability, and meanwhile, the compound of the scheme structure has the pH response characteristic. After the compound is prepared into a fiber membrane, the contact efficiency between compound molecules and acid-base steam to-be-detected substances is remarkably improved, and the compound has extremely high sensitive responsivity to pH.

Description

Technical Field

[0001] The present invention relates to the technical field of fluorescent materials, and in particular to a quinoline group-modified aromatic compound, a preparation method thereof, and application thereof in a pH-responsive fiber membrane. Background Art

[0002] In the interdisciplinary field of chemistry and materials science, fiber membrane materials have become a hot topic in functional material research due to their unique two-dimensional nanostructure characteristics (such as high specific surface area, controllable porosity and surface modifiability). This type of material has demonstrated irreplaceable application value in environmental governance (high-efficiency filtration and separation), biomedicine (targeted drug delivery, tissue engineering scaffolds) and advanced sensing. Although traditional polymer fiber membranes (such as polypropylene and polytetrafluoroethylene) have a mature industrial application foundation, their surface chemical inertness and single functionality have seriously restricted performance breakthroughs in cutting-edge fields such as precision sensing and in vivo imaging. Especially when it comes to molecular-level interaction scenarios, existing materials generally have technical bottlenecks such as response hysteresis and low signal transduction efficiency, which makes it difficult to meet the stringent requirements of intelligent material systems for real-time monitoring and dynamic feedback.

[0003] In the field of molecular optical detection, aggregation-induced emission (AIE) materials based on polyaromatic ring structures have shown significant advantages in constructing multiple stimulus-responsive fluorescent probes due to their unique intramolecular charge transfer (ICT) effect. However, traditional AIE probes face two core challenges in practical applications: first, the strong intermolecular π-π stacking effect in the solid / condensed state leads to excited state energy dissipation, significantly reducing the fluorescence quantum yield; second, the contact dynamics between the probe molecules and the target analytes (such as acidic / alkaline vapors) are limited by the diffusion mass transfer process, resulting in a response time constant generally greater than 30 seconds, which cannot meet the needs of real-time monitoring. Although the aggregation quenching effect can be partially alleviated by molecular engineering methods (such as introducing rigid twisted structures and increasing steric hindrance), there is no technical solution that can simultaneously solve the contradictory relationship between fluorescence efficiency and response rate.

[0004] Therefore, the development of a new fiber membrane-fluorescent probe composite system with both high-sensitivity response and fast kinetic characteristics is of great strategic significance for breaking through the technical bottleneck of existing sensing materials and promoting the practical application of smart materials in environmental monitoring, biomedical diagnosis and other fields. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention proposes a novel quinoline group-modified aromatic compound that, when applied to a fiber membrane, exhibits significant fluorescence intensity and rapidly produces significant contrast changes when the pH changes.

[0006] The present invention also provides a preparation method of the compound.

[0007] The present invention also provides the application of the above compounds.

[0008] According to one aspect of the present invention, a quinoline group-modified aromatic compound is provided, having the following structural formula:

[0009]

[0010] Wherein, R is selected from one of the following structures:

[0011]

[0012] The aromatic compounds modified with quinoline groups according to embodiments of the present invention have at least the following beneficial effects: the compounds have a unique molecular structure, and the quinoline group structure is diverse and flexible. Therefore, the compounds of the present invention have flexible structural design, excellent fluorescence properties and good structural stability. At the same time, the compounds of the present invention have pH-responsive properties. After being prepared into a fiber membrane, the contact efficiency between the compound molecules and the acid, base vapor, and other test substances is significantly improved, and they have extremely high sensitivity to pH.

[0013] According to another aspect of the present invention, a method for preparing the above-mentioned quinoline group-modified aromatic compound is also provided, comprising the following steps:

[0014] 2-(4'-(diphenylamino)-[1,1'-biphenyl]-4-yl)acetonitrile is reacted with a quinolinecarboxaldehyde derivative to produce the quinoline group-modified aromatic compound.

[0015] In some embodiments of the present invention, the structural formula of the quinolinecarboxaldehyde derivative is selected from one of the following structural formulas:

[0016]

[0017] In some embodiments of the present invention, the reaction conditions of 2-(4'-(diphenylamino)-[1,1'-biphenyl]-4-yl)acetonitrile and quinolinecarboxaldehyde derivative include at least one of the following conditions:

[0018] 1) The reaction system is in a solution state, and the solvent used includes an alcohol solvent or an aromatic hydrocarbon solvent (such as benzene, toluene and other aromatic hydrocarbon solvents azeotropically carry water to promote the complete reaction);

[0019] 2) The reaction is carried out under the action of a catalyst, wherein the catalyst comprises an alkaline substance, and the alkaline substance comprises at least one of a primary amine and its salt, a secondary amine and its salt, a tertiary amine and its salt, an inorganic base, a weak acid salt, a combination of a Lewis acid and a tertiary amine, or a basic ion resin;

[0020] 3) The reaction temperature is 85-95°C and the reaction time is 12-36 hours;

[0021] 4) The molar ratio of 2-(4'-(diphenylamino)-[1,1'-biphenyl]-4-yl)acetonitrile to the quinolinecarboxaldehyde derivative is 1:0.9-1.2.

[0022] In some embodiments of the present invention, the reaction conditions of 2-(4'-(diphenylamino)-[1,1'-biphenyl]-4-yl)acetonitrile and quinolinecarboxaldehyde derivative include at least one of the following conditions:

[0023] 1) The reaction system is in a solution state, and the solvent used is ethanol;

[0024] 2) The reaction is carried out under the catalysis of a catalyst, wherein the catalyst includes tetrabutylammonium hydroxide (TBAH), sodium hydroxide, sodium carbonate, potassium fluoride, aluminum phosphate, diammonium hydrogen phosphate, TiCl4 / Py or TiCl4 / Et3N;

[0025] 3) The reaction temperature is 90±2°C and the reaction time is 24±2h;

[0026] 4) The molar ratio of 2-(4'-(diphenylamino)-[1,1'-biphenyl]-4-yl)acetonitrile to the quinolinecarboxaldehyde derivative is 1:1 to 1.1.

[0027] According to another aspect of the present invention, there is also provided an application of the aromatic compound modified with a quinoline group, a fiber product, wherein the raw materials for preparing the fiber product include a polymer and the aromatic compound modified with a quinoline group.

[0028] In some embodiments of the present invention, the polymer includes at least one of polyurethane, polylactic acid (PLA), cellulose acetate (CA), and polystyrene (PS), and any spinnable polymer compound may be used.

[0029] In some embodiments of the present invention, the fiber product comprises a fiber material or a fiber film.

[0030] According to yet another aspect of the present invention, another application of the aromatic compound modified with a quinoline group is provided, that is, application of the aromatic compound modified with a quinoline group in the preparation of pH-responsive fiber products.

[0031] According to another aspect of the present invention, a method for preparing a fiber material is provided, comprising the following steps:

[0032] The electrospinning solution is taken and formed into filaments under the action of high-voltage static electricity to obtain the filaments; wherein the electrospinning solution contains a polymer and the aromatic compound modified with the quinoline group.

[0033] In some embodiments of the present invention, the voltage of the electrostatic action is 5 to 30 kV.

[0034] In some embodiments of the present invention, the voltage of the electrostatic action is 10 to 25 kV.

[0035] In some embodiments of the present invention, the voltage of the electrostatic action is 15 to 20 kV.

[0036] In some embodiments of the present invention, the voltage of the electrostatic action is 16-18 kV, such as 17 kV.

[0037] In some embodiments of the present invention, the working distance during filament formation under the action of high-voltage static electricity is 10 to 15 cm.

[0038] In some embodiments of the present invention, the working distance during filament formation under the action of high-voltage electrostatics is 13±1 cm.

[0039] According to another aspect of the present invention, a method for preparing a fiber membrane is provided, comprising the following steps:

[0040] The fiber materials prepared by the above preparation method are interwoven to form a fiber membrane.

[0041] In some embodiments of the present invention, the preparation method includes the step of depositing the fiber material into a film. Electrospinning technology uses a high-voltage electric field (typically 5-30kV) to stretch a polymer solution or melt into nano- to micron-sized fibers and deposit them into a film. The process begins with the formation of a charged Taylor cone at the spinneret. Under the action of the electric field force, the jet undergoes severe stretching and whipping instability. The solvent evaporates rapidly, causing the fibers to solidify. Finally, the fibers are deposited into a porous mesh film through a static or dynamic collector (such as a rotating drum).

[0042] According to another aspect of the present invention, there is also provided the use of the aromatic compound modified with the quinoline group or the fiber product in acid-base detection, environmental monitoring, and industrial control.

[0043] In some embodiments of the present invention, the industrial control includes anti-counterfeiting or textile inspection. The invention can be applied to a variety of industrial controls that require rapid response, directly or indirectly related to pH. Furthermore, based on the multi-responsive nature of the quinoline group, the invention can also be applied to other industrial controls, particularly those requiring rapid response.

[0044] The fiber material of the present invention has excellent fluorescence properties. Not only is the fluorescence intensity significant, but also its fluorescence color can produce significant contrast changes in a very short period of time when the acid-base environment changes. This characteristic makes the fiber membrane extremely sensitive and accurate in the field of acid-base detection. Even more remarkable is that the fiber membrane responds extremely quickly to acid-base environments and can react within just 1 second, providing strong technical support for real-time monitoring and rapid judgment. Therefore, in the fields of acid-base detection, environmental monitoring, anti-counterfeiting, textile testing, and industrial control that requires rapid response, the fiber membrane of the present invention has demonstrated huge potential application value and provided innovative solutions for the development of related industries.

[0045] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention.

[0046] In the description of the present invention Represents the junction site. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 The aromatic compound modified with a quinoline group obtained in Example 1 of the present invention 1 H NMR spectrum.

[0048] Figure 2 The aromatic compound modified with a quinoline group obtained in Example 2 of the present invention 1 H NMR spectrum.

[0049] Figure 3 The aromatic compound modified with quinoline group prepared in Example 3 of the present invention is 1 H NMR spectrum.

[0050] Figure 4 The aromatic compound modified with quinoline group prepared in Example 4 of the present invention 1 H NMR spectrum.

[0051] Figure 5 These are the characterization results of pure PLA and the fiber membrane prepared using TPABCNnQU (n=2, 3, 4) in Example 8 of the present invention under SEM magnification of 10k: (a) pure PLA, (b) PLA-TPABCN2QU, (c) PLA-TPABCN3QU, and (d) PLA-TPANCN4QU.

[0052] Figure 6These are the characterization results of pure PLA and the fiber membrane prepared using TPABCNnQU (n=5, 6, 7 or 8) in Example 8 of the present invention under SEM magnification of 10k: (a) PLA-TPABCN5QU, (b) PLA-TPABCN6QU, (c) PLA-TPABCN7QU, and (d) PLA-TPANCN8QU.

[0053] Figure 7 Acid stimulation response test and fluorescence photograph (365 nm) of PLA-TPABCN2QU prepared in Example 8 of the present invention, (a) normalized PL spectrum, (b) XRD spectrum of the compound and micro-nanofiber membrane, (c) fluorescence photograph under external stimulation (365 nm): O is the original sample, O-HCl is the acid-fumigated sample, and O-HCl-NH3 is the acid-fumigated and alkali-fumigated sample.

[0054] Figure 8 Acid stimulation response test and fluorescence photograph (365 nm) of PLA-TPABCN3QU prepared in Example 8 of the present invention, (a) normalized PL spectrum, (b) XRD spectrum of the compound and micro-nanofiber membrane, (c) fluorescence photograph under external stimulation (365 nm): O is the original sample, O-HCl is the acid-fumigated sample, and O-HCl-NH3 is the acid-fumigated and alkali-fumigated sample.

[0055] Figure 9 Acid stimulation response test and fluorescence photograph (365 nm) of PLA-TPABCN4QU prepared in Example 8 of the present invention, (a) normalized PL spectrum, (b) XRD spectrum of the compound and micro-nanofiber membrane, (c) fluorescence photograph under external stimulation (365 nm): O is the original sample, O-HCl is the acid-fumigated sample, and O-HCl-NH3 is the acid-fumigated and alkali-fumigated sample.

[0056] Figure 10 Acid stimulation response test and fluorescence photograph (365 nm) of PLA-TPABCN5QU prepared in Example 8 of the present invention, (a) normalized PL spectrum, (b) XRD spectrum of the compound and micro-nanofiber membrane, (c) fluorescence photograph under external stimulation (365 nm): O is the original sample, O-HCl is the acid-fumigated sample, and O-HCl-NH3 is the acid-fumigated and alkali-fumigated sample.

[0057] Figure 11 Acid stimulation response test and fluorescence photograph (365 nm) of PLA-TPABCN6QU prepared in Example 8 of the present invention, (a) normalized PL spectrum, (b) XRD spectrum of the compound and micro-nanofiber membrane, (c) fluorescence photograph under external stimulation (365 nm): O is the original sample, O-HCl is the acid-fumigated sample, and O-HCl-NH3 is the acid-fumigated and alkali-fumigated sample.

[0058] Figure 12 Acid stimulation response test and fluorescence photograph (365 nm) of PLA-TPABCN7QU prepared in Example 8 of the present invention, (a) normalized PL spectrum, (b) XRD spectrum of the compound and micro-nanofiber membrane, (c) fluorescence photograph under external stimulation (365 nm): O is the original sample, O-HCl is the acid-fumigated sample, and O-HCl-NH3 is the acid-fumigated and alkali-fumigated sample.

[0059] Figure 13 Acid stimulation response test and fluorescence photograph (365 nm) of PLA-TPABCN8QU prepared in Example 8 of the present invention, (a) normalized PL spectrum, (b) XRD spectrum of the compound and micro-nanofiber membrane, (c) fluorescence photograph under external stimulation (365 nm): O is the original sample, O-HCl is the acid-fumigated sample, and O-HCl-NH3 is the acid-fumigated and alkali-fumigated sample. DETAILED DESCRIPTION

[0060] The following will clearly and completely describe the concept of the present invention and the technical effects produced in conjunction with the embodiments, so as to fully understand the purpose, characteristics and effects of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention. Unless otherwise specified, the test methods used in the embodiments are all conventional methods; the materials, reagents, etc. used, unless otherwise specified, are reagents and materials obtained from commercial channels. Unless otherwise specified, the same parameter in each embodiment has the same value. The embodiments described below are exemplary and are only used to explain the present invention, and are not to be understood as limitations of the present invention.

[0061] In the description of the present invention, reference to the term "some embodiments" or the like indicates that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0062] In the description of the present invention, if there is a description of first, second, etc., it is only for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0063] Example 1

[0064] This example provides an aromatic compound modified with a quinoline group, the structural formula of which is as follows:

[0065] Where R is

[0066] The specific preparation process is as follows: Using the synthesis of TPABCN2QU as an example: 2-(4'-(diphenylamino)-[1,1'-biphenyl]-4-yl)acetonitrile (0.5 g, 1.39 mmol) was weighed into a three-necked flask, and 20 ml of anhydrous ethanol was added with stirring to dissolve. The temperature of the oil bath was adjusted to 90°C and refluxed. After complete dissolution, quinoline-2-carboxaldehyde (0.24 g, 1.51 mmol) was added. After the solution cleared, tetrabutylammonium hydroxide (TBAH) was added as a catalyst, and the reaction was continued for 24 hours. Filter the mixture, and rinse the residue twice with ethanol to obtain a green solid powder (0.59 g, 85%).

[0067]

[0068] The product obtained by the above operation was subjected to structural characterization, and the results were as follows: Figure 1 shown.

[0069] The specific data are as follows: 1 H NMR (500MHz, DMSO-d6) δ8.66(s,1H),8.34(s,1H),7.94(s,1H),7.81(t,J=8.4Hz,3H),7.44(s,1H),7.23–6.90(m,19H).

[0070] Example 2

[0071] This example provides an aromatic compound modified with a quinoline group, which differs from Example 1 in that: R is

[0072]

[0073] The preparation process thereof differs from that of Example 1 in that quinoline-2-carboxaldehyde is replaced by quinoline-4-carboxaldehyde, and an orange-yellow powder is obtained with a yield of 70%.

[0074] The product obtained by the above operation was subjected to structural characterization, and the results were as follows: Figure 2 shown.

[0075] The specific data are as follows: 1H NMR (500MHz, DMSO-d6) δ9.07(d,J=4.5Hz,1H),8.81(s,1H),8.27(d,J=8.5Hz,1H),8.14(d,J=8.4Hz,1H),8.00(d,J=8.5Hz,2 H), 7.93 (d, J = 4.5Hz, 1H), 7.87 (d, J = 8.3Hz, 3H), 7.72 (d, J = 8.6Hz, 3H), 7.35 (dd, J = 8.8, 6.9Hz, 4H), 7.13–7.03 (m, 7H). Example 3

[0076] This example provides an aromatic compound modified with a quinoline group, which differs from Example 1 in that: R is

[0077]

[0078] The preparation process thereof differs from that of Example 1 in that quinoline-2-carboxaldehyde is replaced by quinoline-6-carboxaldehyde, and the yield of the obtained yellow-green powder is 78%.

[0079] The product obtained by the above operation was subjected to structural characterization, and the results were as follows: Figure 3 shown.

[0080] The specific data are as follows: 1 H NMR (500MHz, DMSO-d6) δ8.99(s,1H),8.52(s,1H),8.47(d,J=8.3Hz,1H),8.37–8.30(m,2H),8.16(d,J=8.8Hz,1H),7.90(d,J=8 .5Hz,2H),7.83(d,J=8.5Hz,2H),7.70(d,J=8.6Hz,2H),7.63(dd,J=8.3,4.2Hz,1H),7.35(t,J=7.9Hz,4H),7.13–7.03(m,8H).

[0081] Example 4

[0082] This example provides an aromatic compound modified with a quinoline group, which differs from Example 1 in that: R is

[0083]

[0084] The preparation process is different from that of Example 1 in that quinoline-2-carboxaldehyde is replaced by quinoline-8-carboxaldehyde, and the yield of the obtained yellow-green powder is 83%.

[0085] The product obtained by the above operation was subjected to structural characterization, and the results were as follows: Figure 4 shown.

[0086] The specific data are as follows: 1 H NMR (500MHz, DMSO-d6) δ9.05(s,1H),9.02(s,1H),8.54–8.47(m,2H),8.18(d,J=8.9Hz,1H),7.89(d,J=8.5Hz,2H ),7.85(d,J=8.5Hz,2H),7.81(t,J=7.8Hz,1H),7.70(t,J=8.7Hz,3H),7.38–7.31(m,4H),7.09(q,J=7.6Hz,7H).

[0087] Example 5

[0088] This example provides an aromatic compound modified with a quinoline group, which differs from Example 1 in that: R is

[0089]

[0090] The difference between the preparation process and Example 1 is that quinoline-2-carboxaldehyde is replaced by quinoline-3-carboxaldehyde, and the yield of the green powder is 75%.

[0091] The product obtained by the above operation was characterized by nuclear magnetic resonance, and the results showed that the target compound was obtained (the reaction principle is similar to that of Examples 1 to 4, and the nuclear magnetic resonance data are not shown one by one to avoid redundancy).

[0092] Example 6

[0093] This example provides an aromatic compound modified with a quinoline group, which differs from Example 1 in that: R is

[0094]

[0095] The preparation process thereof differs from that of Example 1 in that quinoline-2-carboxaldehyde is replaced by quinoline-5-carboxaldehyde, and the yield of the obtained yellow-green powder is 79%.

[0096] The product obtained by the above operation was characterized by nuclear magnetic resonance, and the results showed that the target compound was obtained (the reaction principle is similar to that of Examples 1 to 4, and the nuclear magnetic resonance data are not shown one by one to avoid redundancy).

[0097] Example 7

[0098] This example provides an aromatic compound modified with a quinoline group, which differs from Example 1 in that: R is

[0099]

[0100] The preparation process is different from that of Example 1 in that quinoline-2-carboxaldehyde is replaced by quinoline-5-carboxaldehyde, and the yield of the obtained yellow-green powder is 80%.

[0101] The product obtained by the above operation was characterized by nuclear magnetic resonance, and the results showed that the target compound was obtained (the reaction principle is similar to that of Examples 1 to 4, and the nuclear magnetic resonance data are not shown one by one to avoid redundancy).

[0102] Example 8

[0103] In this example, a fiber membrane was prepared. 0.05g of the compound TPABCNnQU prepared in Examples 1-7 and 1g of a polymer (PLA) were dissolved in 8.95g of a DMF / DCM (v / v = 1 / 2) mixture to prepare an electrospinning solution. The solution was then loaded into a 10mL syringe and extruded through a spinneret at a rate of 1mL / h. The solution was then formed into filaments and deposited into a membrane under the action of high-voltage electrostatics. The spinning voltage was 17kV, the working distance was 13cm, and silicone oil paper was used as a grounded collector.

[0104] The microstructure of pure PLA and fiber membranes (PLA-TPABCNnQU) prepared by using aromatic compounds modified with quinoline groups prepared in Examples 1 to 7 was observed by scanning electron microscopy (SEM). Figure 5 and 6 Scanning electron microscopy revealed that the surface of the prepared composite fiber membrane was uniform and smooth, with no granular aggregates or beaded fibers observed. This indicates that the TPABCNnQU compound has good compatibility with polylactic acid, and that the addition of the TPABCNnQU compound does not affect the spinning and fiber-forming properties of polylactic acid.

[0105] Example 9

[0106] In this example, a fiber membrane was prepared. 0.05 g of the compound TPABCNnQU prepared in Examples 1-7 and 1 g of polymer (CA) were dissolved in 8.95 g of a DMF / DCM (v / v = 1 / 2) mixture to prepare an electrospinning solution. The solution was then loaded into a 10 mL syringe and extruded through a spinneret at a rate of 1 mL / h. The solution formed filaments and subsequently deposited into a membrane under the action of high-voltage electrostatics. The spinning voltage was 17 kV, the working distance was 13 cm, and silicone oil paper was used as a grounded collector.

[0107] Example 10

[0108] In this example, a fiber membrane was prepared. 0.05 g of the compound TPABCNnQU prepared in Examples 1-7 and 1 g of a polymer (polystyrene (PS)) were dissolved in 8.95 g of a DMF / DCM (v / v = 1 / 2) mixture to prepare an electrospinning solution. The solution was then loaded into a 10 mL syringe and extruded through a spinneret at a rate of 1 mL / h. The solution formed filaments and subsequently deposited into a membrane under the action of high-voltage electrostatics. The spinning voltage was 17 kV, the working distance was 13 cm, and silicone oil paper was used as a grounded collector.

[0109] The fiber membrane materials prepared in Examples 8 to 10 were tested for pH response performance. The test results of the fiber membrane material prepared in Example 8 are as follows: Figures 7-13 shown.

[0110] The testing process is as follows:

[0111] The micro-nanofiber membrane prepared by the above operation was cut into square samples of 1 cm × 1 cm in size, and 1 mL of concentrated hydrochloric acid was placed in a 20 mL sample bottle and fumigated for 5-10 seconds before fluorescence spectrometer testing. Subsequently, 1 mL of 20% wt ammonia water was placed in a 20 mL sample bottle and fumigated for 5-10 seconds for fluorescence spectrum testing.

[0112] like Figure 7 As shown, during the acid stimulation response experiment, the fluorescence emission of the micro-nanofiber membrane containing 1% PLA-TPABCN2QU compound showed no significant change after hydrochloric acid vapor fumigation. Fluorescence spectrometer testing revealed that after hydrochloric acid vapor fumigation, its maximum emission wavelength red-shifted from 521nm to 523nm. After ammonia vapor fumigation, the fluorescence test showed that it returned to the initial maximum emission wavelength of 521nm. Although there was no obvious change to the naked eye, it showed good reversibility. XRD testing revealed that the mixing with PLA to prepare the spinning solution resulted in uniform dispersion and amorphous state in the micro-nanofiber membrane. The preparation of micro-nanofiber fibers also fixed its molecular conformation, resulting in reversible acid-base stimulus response.

[0113] like Figure 8As shown, during an acid-responsive experiment, a micro-nanofiber membrane containing 1% PLA-TPABCN3QU compound exhibited a fluorescence shift from green to yellow-green after approximately 3 seconds of hydrochloric acid vapor fumigation. The maximum emission wavelength also red-shifted by 7 nm from 520 nm to 527 nm. Deprotonation with NH3 vapor restored the wavelength to its initial state. XRD analysis revealed that the PLA-TPABCN3QU spinning solution, when blended with PLA, resulted in a uniform dispersion and amorphous state within the micro-nanofiber membrane. Furthermore, the formation of micro-nanofibers stabilized the molecular conformation, resulting in reversible acid-base responsiveness. This demonstrates the stability and reversibility of the PLA-TPABCN3QU micro-nanofiber membrane's acid-base responsiveness.

[0114] like Figure 9 As shown, during the acid stimulation response experiment, the fluorescence color of the micro-nanofiber membrane containing 1% PLA-TPABCN4QU compound changed from yellow to bright yellow after being fumigated with hydrochloric acid vapor for approximately 3 seconds. The maximum emission wavelength of the fluorescence also red-shifted from 541nm to 552nm, a red shift of 11nm. Deprotonation with NH3 vapor restored the wavelength to its initial state. XRD testing revealed that the spinning solution prepared by blending with PLA resulted in uniform dispersion and amorphous state in the micro-nanofiber membrane. Furthermore, the molecular conformation of the prepared micro-nanofiber tends to be fixed, resulting in reversible acid-base stimulation response. This demonstrates that the acid-base stimulation response of the PLA-TPABCNnQU micro-nanofiber membrane is stable and reversible.

[0115] like Figure 10 As shown in the figure, during the acid stimulation response experiment, the fluorescence color of the micro-nanofiber membrane containing 1% PLA-TPABCN5QU compound changed from green to yellow-green after being fumigated with hydrochloric acid vapor for approximately 3 seconds. The maximum emission wavelength also red-shifted from 519nm to 547nm, a 28nm red-shift. Deprotonation with NH3 vapor restored the wavelength to its initial state. XRD analysis revealed that the PLA-TPABCN5QU micro-nanofiber membrane was uniformly dispersed in the spinning solution, exhibiting an amorphous state. Furthermore, the formation of micro-nanofiber membranes stabilized the molecular conformation, resulting in reversible acid-base responsiveness. This demonstrates the good stability and reversibility of the PLA-TPABCN5QU micro-nanofiber membrane's acid-base responsiveness.

[0116] like Figure 11As shown, during the acid stimulation response experiment, the fluorescence color of the micro-nanofiber membrane containing 1% PLA-TPABCN6QU changed from green to yellow after being fumigated with hydrochloric acid vapor for approximately 3 seconds, and the maximum emission wavelength also red-shifted from 508nm to 567nm, a 59nm red-shift. Deprotonation with NH3 vapor restored the wavelength to its initial state. XRD analysis revealed that the PLA-TPABCN6QU micro-nanofiber membrane, when blended with PLA to prepare the spinning solution, was uniformly dispersed in the micro-nanofiber membrane, exhibiting an amorphous state. Furthermore, the formation of micro-nanofiber membranes stabilized their molecular conformation, resulting in reversible acid-base responsiveness. This demonstrates the excellent stability and reversibility of the PLA-TPABCN6QU micro-nanofiber membrane's acid-base responsiveness.

[0117] like Figure 12 As shown in the acid stimulation response experiment, after being fumigated with hydrochloric acid vapor for approximately 3 seconds, the fluorescence color of a micro-nanofiber membrane containing 1% PLA-TPABCN7QU changed from green to dark yellow, and the maximum emission wavelength also red-shifted by 83 nm from 508 nm to 591 nm. Deprotonation with NH3 vapor restored the wavelength to its initial state. XRD analysis revealed that the PLA-TPABCN7QU micro-nanofiber membrane, when blended with PLA to prepare the spinning solution, was uniformly dispersed in the micro-nanofiber membrane, exhibiting an amorphous state. Furthermore, the formation of micro-nanofiber membranes stabilized their molecular conformation, resulting in reversible acid-base responsiveness. This demonstrates the excellent stability and reversibility of the PLA-TPABCN7QU micro-nanofiber membrane's acid-base responsiveness.

[0118] like Figure 13 As shown, during the acid stimulation response experiment, the micro-nanofiber membrane containing 1% PLA-TPABCN8QU showed no significant change in fluorescence emission after hydrochloric acid vapor fumigation. Fluorescence spectrometer testing revealed that the maximum emission wavelength red-shifted from 512nm to 514nm after hydrochloric acid vapor fumigation. After ammonia vapor fumigation, the fluorescence test showed a return to the initial maximum emission wavelength of 512nm. Although there was no visible change, the membrane exhibited good reversibility. XRD testing revealed that the PLA-TPABCN8QU compound was uniformly dispersed in the micro-nanofiber membrane during the spinning solution preparation, exhibiting an amorphous state. Furthermore, the molecular conformation of the micro-nanofiber membrane tended to be fixed due to its preparation into micro-nanofiber, resulting in reversible acid-base stimulus response.

[0119] The properties of the fiber membrane materials prepared in Examples 9 and 10 are similar and are not shown one by one to avoid redundancy.

[0120] 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 of ordinary technicians in the relevant technical field without departing from the scope of the present invention.

Claims

1. A quinoline group-modified aromatic compound, characterized in that: It has the following structural formula: Wherein, R is selected from one of the following structures:

2. The method for preparing a quinoline group-modified aromatic compound according to claim 1, wherein: The steps include: 2-(4'-(diphenylamino)-[1,1'-biphenyl]-4-yl)acetonitrile is reacted with a quinolinecarboxaldehyde derivative to produce the quinoline group-modified aromatic compound.

3. The preparation method according to claim 2, wherein: The reaction conditions of 2-(4'-(diphenylamino)-[1,1'-biphenyl]-4-yl)acetonitrile and quinolinecarboxaldehyde derivative include at least one of the following conditions: 1) The reaction system is in a solution state, and the solvent used includes an alcohol solvent or an aromatic hydrocarbon solvent; 2) The reaction is carried out under the action of a catalyst, wherein the catalyst comprises an alkaline substance, and the alkaline substance comprises at least one of a primary amine and its salt, a secondary amine and its salt, a tertiary amine and its salt, an inorganic base, a weak acid salt, a combination of a Lewis acid and a tertiary amine, or a basic ion resin; 3) The reaction temperature is 85-95°C and the reaction time is 12-36 hours; 4) The molar ratio of 2-(4'-(diphenylamino)-[1,1'-biphenyl]-4-yl)acetonitrile to the quinolinecarboxaldehyde derivative is 1:0.9-1.

2.

4. A fiber product, characterized in that: The raw materials for preparing the fiber product include a polymer and the aromatic compound modified with a quinoline group as claimed in claim 1.

5. The fiber product according to claim 4, characterized in that: The polymer includes at least one of polyurethane, polylactic acid, cellulose acetate, and polystyrene.

6. Use of the quinoline group-modified aromatic compound according to claim 1 in the preparation of pH-responsive fiber products.

7. A method for preparing a fiber material, characterized in that: The steps include: The electrospinning solution is taken and formed into filaments under the action of high-voltage static electricity to obtain the obtained product; wherein the electrospinning solution contains a polymer and the aromatic compound modified with a quinoline group as claimed in claim 1.

8. A method for preparing a fiber membrane, characterized in that: The steps include: The fiber material obtained by the preparation method according to claim 7 is interwoven to form a fiber membrane.

9. Use of the quinoline group-modified aromatic compound according to claim 1 or the fiber product according to claim 4 or 5 in acid-base detection, environmental monitoring, and industrial control.

10. The use according to claim 9, characterized in that: The industrial control includes anti-counterfeiting or textile inspection.

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