CN113563566A

CN113563566A - Amplified conjugated fluorescent porous polymer, fluorescent sensing film, and preparation method and application thereof

Info

Publication number: CN113563566A
Application number: CN202111118876.2A
Authority: CN
Inventors: 陈海波; 李鹏; 李灵锋
Original assignee: Suzhou University
Current assignee: Suzhou University
Priority date: 2021-09-23
Filing date: 2021-09-23
Publication date: 2021-10-29
Anticipated expiration: 2041-09-23
Also published as: CN113563566B

Abstract

The invention relates to the technical field of fluorescent sensing materials, in particular to an amplified conjugated fluorescent porous polymer, a fluorescent sensing film, and a preparation method and application thereof. The porous polymer provided by the invention has a structure shown in a formula 3-formula 5, is used for preparing a fluorescent sensing film, has sensitive and rapid response signal and high selectivity, and can be widely applied to the fluorescent detection of gaseous trace nitro explosives, peroxide explosives, biomolecules, heavy metals and drugs.

Description

Amplified conjugated fluorescent porous polymer, fluorescent sensing film, and preparation method and application thereof

Technical Field

The invention relates to the technical field of fluorescent sensing materials, in particular to an amplified conjugated fluorescent porous polymer, a fluorescent sensing film, and a preparation method and application thereof.

Background

In recent years, with continuous progress of industrial level, the use of chemicals is becoming more and more common, and while the living level and convenience of chemicals are greatly improved, the chemicals also pose threats to ecological environment, public safety, public health and other aspects due to the dangerousness of the chemicals, so that the rapid and trace monitoring of the chemicals, especially dangerous chemicals, is urgently needed in the relevant fields of industrial control, environmental monitoring, public safety and the like.

The dangerous chemicals refer to highly toxic chemicals and other chemicals which have the properties of toxicity, corrosion, explosion, combustion-supporting and the like and are harmful to human bodies, facilities and environments, the dangerous chemicals are various in variety, and the existing chemicals with higher danger mainly comprise explosives, heavy metal ions, organic amine pollutants, nerve gases, synthetic drugs and the like. At present, detection aiming at the dangerous chemicals is mainly based on a gas chromatography-mass spectrometry combined technology, an immunoassay method, infrared chromatography, ion chromatography and the like, and the gas chromatography-mass spectrometry combined technology is complex in equipment and is not suitable for on-site rapid detection; the immunoassay method has good specificity and high sensitivity, but the preparation of the monoclonal antibody is difficult and tedious, the detection period is long, and the stability of the antibody is poor, so that the monoclonal antibody is not suitable for long-time storage; the infrared chromatography technology is greatly influenced by water and carbon dioxide, and the detection sensitivity is low; ion mobility spectrometry techniques typically employ radioactive sources, which have an impact on the operator's body.

The fluorescence sensor technology is a technology for analyzing and detecting a substance to be detected through the fluorescence emission intensity, the maximum emission wavelength position, the fluorescence spectrum morphology, the fluorescence life and the change of signals such as fluorescence anisotropy and the like of a fluorescence active molecule or a material before and after the signals react with the substance to be detected.

In recent years, fluorescent sensors based on conjugated polymers have attracted extensive attention due to the advantages of convenient, rapid and sensitive test process, no need of pretreatment of samples and the like, but the polymers adopted by the existing fluorescent sensors cannot further meet the requirements of the fluorescent sensors on rapidness, sensitivity and high selectivity, so that a new polymer is urgently needed to be developed and applied to the fluorescent sensors to detect dangerous goods more efficiently and sensitively.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to overcome the defect that the polymer adopted by the existing fluorescence sensor can not further meet the requirements of the fluorescence sensor on rapidness, sensitivity and high selectivity, and further provides an amplified conjugated fluorescence porous polymer, a fluorescence sensing film, and preparation methods and applications thereof.

The scheme adopted by the invention is as follows:

an amplified conjugated fluorescent porous polymer having a structure represented by formula 3 to formula 5:

，

wherein R is₁-R₂Identical or different, each R₁、R₂Independently selected from H, halogen, hydroxyl, cyano, amino, nitro, carboxyl and C_1-12Alkyl radical, C_2-12Alkenyl radical, C_2-12Alkynyl, C_5-12Aryl radical, C_3-12Cycloalkyl radical, C_3-12Cycloalkenyl radical, C_4-12Heterocyclic group, C_4-12Heteroaryl, -R⁵OR⁶、-OR⁵OR⁶、-OR⁵、-SR⁵、-SO₂R⁵、-C(O)R⁵、-S(O)R⁵、-NR⁵R⁶、-COOR⁵、-OC(O)R⁵、-CONR⁵R⁶、-NR⁵COR⁶；

R⁵And R⁶Are the same or different and are each independently selected from H, C_1-12Alkyl radical, C_2-12Alkenyl radical, C_2-12Alkynyl, C_5-12Aryl radical, C_3-12Cycloalkyl radical, C_3-12Cycloalkenyl or C_4-12A heteroaryl group;

R_a、R_bthe same or different, are independently selected from C_1-12Alkyl, alkoxy;

n is selected from the group consisting of integers between 1 and 20And (4) counting. Optionally, n is selected from 1, 5, 8, 10, 15, 18, 20. Preferably, R₁-R₂Identical or different, each R₁、R₂Independently selected from H, halogen, hydroxyl, cyano, amino, nitro, carboxyl and C_1-12Alkyl, -R⁵OR⁶、-OR⁵OR⁶、-OR⁵；

R⁵And R⁶Are the same or different and are each independently selected from C_1-12An alkyl group;

R_a、R_bthe same or different, are independently selected from C_1-12An alkyl group.

Preferably, the first and second liquid crystal materials are,

said C is_1-12The alkyl is selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tertiary butyl, pentyl, hexyl, heptyl and octyl;

said C is_3-12The cycloalkyl is selected from cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl;

said C is_5-12Aryl is selected from phenyl, biphenyl, naphthyl, binaphthyl, phenylnaphthyl, fluorenyl, phenylfluorenyl, phenanthryl, anthryl, indenyl, pyrenyl;

said C is_4-12Heteroaryl is selected from the group consisting of furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, triazolyl, indolyl, quinolinyl, isoquinolinyl.

Preferably, the method comprises the following steps: carrying out coupling reaction on a compound shown in a raw material formula A and a compound shown in a raw material formula B to obtain a polymer shown in a formula 3-5;

the compound shown in the formula A of the raw material has the following structure:

；

the compound shown in the formula B of the raw material has a structure shown in any one of the following formulas:

、

、

；

wherein X is halogen. Preferably, X is selected from chlorine, bromine, iodine.

The invention also provides the application of the polymer or the polymer prepared by the preparation method in fluorescence detection of gaseous nitro explosives, peroxide explosives, biomolecules, heavy metals and drugs. Optionally, the gaseous nitro-explosive is a gaseous trace nitro-explosive.

The present invention relates generally to the use of the above polymers in nitro explosives, but the scope of application is not limited thereto, and it is within the scope of protection to use the molecules encompassed by the present invention.

Alternatively, the nitro-explosive may be TNT, a class B explosive, octogen, hexogen or nitramine.

The invention also provides a fluorescent sensing film which is prepared by adopting the polymer or the polymer prepared by the preparation method.

Preferably, the thickness of the fluorescence sensing film is 5-1000 nm, and preferably, the thickness of the fluorescence sensing film is 5-200 nm.

The invention also provides a preparation method of the fluorescence sensing film, which comprises the following steps: the fluorescence sensing film is prepared on the substrate of glass, quartz, silicon chips, organic and high-molecular solid carriers, microspheres, nano particles, nano fibers or nano tubes by a pulling, spin coating or evaporation method. Preferably, the substrate is colorless and transparent and has good light transmittance.

Preferably, the preparation method of the fluorescence sensing film comprises the following steps:

1) washing glass or quartz substrate with water, blow-drying, and immersing in a solution containing H₂SO₄And H₂O₂In the mixed solution of (1), the mixed solution is heated to activate the glass or quartz substrateCooling after activation, taking the glass or quartz substrate out of the mixed solution, washing with water, and drying to obtain an activated substrate;

2) mixing a silanization reagent with an organic solvent to prepare a silanization reagent solution;

3) soaking the activated substrate prepared in the step 1) into the silanization reagent solution obtained in the step 2), taking out the substrate after soaking is finished, washing with an organic solvent, and drying to obtain a silanized substrate;

4) forming an organic polymer fluorescent coating on the silanized substrate obtained in the step 3) by using a pulling, spin coating or evaporation method for the fluorescent polymer solution to obtain the fluorescent sensing film.

Preferably, the mixed solution in the step 1) is prepared by mixing 96-98% of H by mass fraction₂SO₄The solution and the mass fraction of H are 25-35 percent₂O₂The solution is prepared according to the volume ratio of (2.8-3.2) to 1; the activation temperature is 80-100 ℃, and the activation time is 1-2 h;

in the step 2), the silanization reagent is selected from one of chloropropylene oxide, methyl chlorosilane oxide, propylamine chlorosilane oxide and 3-glycidoxypropylether trimethoxy silane; the organic solvent is toluene; the silylation reagent solution is a conventional silylation reagent solution in the field, and the concentration and the dosage of the silylation reagent solution are conventional dosages in the field, which are not described herein again.

In the step 3), the soaking temperature is 40-60 ℃, the soaking time is 12-48h, and the organic solvent is toluene;

in the step 4), the fluorescent polymer is the fluorescent polymer or the fluorescent polymer prepared by the preparation method; the concentration of the fluorescent polymer solution is 0.1-10 mol/ml, and the solvent is any one of dichloromethane, trichloromethane, tetrahydrofuran and pyridine.

The invention also provides an application of the fluorescent sensing film or the fluorescent sensing film prepared by the preparation method in preparation of a fluorescent sensing device.

Optionally, the fluorescence sensing device has only one detection gas path, and multiple fluorescence sensing thin-film devices can be simultaneously carried in the same gas path to simultaneously test the sensing performance of multiple fluorescence sensing materials.

The invention has the beneficial effects that:

the novel amplified conjugated fluorescent porous polymer provided by the invention has a specific structure shown in a formula 3-5, the structure adopts pentacene rigid monomer coupling, pi-pi quenching between molecules is effectively prevented during film forming, the fluorescent intensity is enhanced to a certain extent, meanwhile, the structure is embedded into a molecular chain, a molecular gap is formed during film forming, gaseous diffusion of explosives is facilitated, the response time of a fluorescent sensor can be effectively shortened through the design of a high molecular skeleton formed by mutual crosslinking of a rigid group and a condensed ring, and therefore, the high molecular fluorescent material sensor is applied to the field of rapid detection.

Compared with monomer and small molecular fluorescent materials, the amplified conjugated fluorescent porous polymer provided by the invention has the advantages that the fluorescence intensity with the same molar weight is increased by hundreds of times and thousands of times, and the sensing performance can be theoretically increased by hundreds of times and thousands of times when the amplified conjugated fluorescent porous polymer is prepared into a fluorescent sensor for use. Meanwhile, the fluorescent polymer can effectively inhibit the problem of fluorescence quenching caused by aggregation of the fluorescent material in a solid state, the luminous performance of the fluorescent polymer in a solid state is good, obvious fluorescence quenching can be generated in a short time under the action of the fluorescent polymer and gaseous explosives, the detection of the gaseous trace explosives can be realized according to the quenching of the fluorescence intensity of the fluorescent polymer, and the fluorescent polymer is a novel fluorescent sensing material for detecting the gaseous trace explosives. Meanwhile, the amplified conjugated fluorescent porous polymer provided by the invention is used for preparing a fluorescent sensing film, has sensitive and quick response signal and high selectivity, can be widely applied to the fluorescent detection of gaseous trace nitro explosives, peroxide explosives, biomolecules, heavy metals and drugs, can be repeatedly used for hundreds of times to detect the explosives, is estimated by a sensing mechanism, can be used for infinite times, and has the characteristics of high efficiency, convenience, quickness in detection and convenience for use by non-professionals.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a nuclear magnetic hydrogen spectrum of Compound 2-1.

FIG. 2 is a nuclear magnetic hydrogen spectrum of Compound 2-2.

FIG. 3 is a nuclear magnetic hydrogen spectrum of compound 2-3.

FIG. 4 is a nuclear magnetic hydrogen spectrum of compounds 2-4.

FIG. 5 is a high resolution spectrum of compounds 2-4.

Detailed Description

The following examples are provided to further understand the present invention, not to limit the scope of the present invention, but to provide the best mode, not to limit the content and the protection scope of the present invention, and any product similar or similar to the present invention, which is obtained by combining the present invention with other prior art features, falls within the protection scope of the present invention.

The examples do not show the specific experimental steps or conditions, and can be performed according to the conventional experimental steps described in the literature in the field. The reagents or instruments used are not indicated by manufacturers, and are all conventional reagent products which can be obtained commercially.

Example 1

This example provides intermediates 2-4, whose synthetic pathways are shown below:

；

the preparation method of the monomers 2-4 specifically comprises the following steps:

1) synthesis of Compound 2-1

；

Placing anthracene (3.55 g, 20.0 mmol), 1, 4-benzoquinone (1.30 g, 12.0 mmol) and 2,3,5, 6-tetrachlorobenzoquinone (4.90 g, 20.0 mmol) into a reaction bottle, adding glacial acetic acid (125 mL), heating, refluxing, stirring and reacting for 16 h, recovering to room temperature after the reaction is finished, performing suction filtration by using a Buchner funnel under vacuum condition to obtain a filter cake solid, washing the solid by using glacial acetic acid, methanol and diethyl ether to obtain a crude product, separating and purifying the crude product by using silica gel column chromatography, wherein the used eluent is a mixed solvent of dichloromethane and ethyl acetate in a volume ratio of 50: 1, and finally obtaining a yellow solid 2-1 (3.10 g, 68%). The nuclear magnetic hydrogen spectrum of the compound 2-1 is shown in FIG. 1.

2) Synthesis of Compound 2-2

；

Trimethylsilylacetylene (0.80 g, 8.15 mmol) was placed in a three-necked flask, and ultra-dry tetrahydrofuran (15 mL) treated with Na-K alloy was added to the flask under nitrogen protection with a syringe, 0^oN-butyllithium (3.20 mL, 8.15 mmol, 2.5M in n-hexane), 0, was added under C^oStirring for 45 min under C, adding compound 2-1 (0.92 g, 2.00 mmol), recovering to room temperature, stirring for reaction for 16 h, after the reaction is finished, adjusting the pH value to weak acidity with dilute hydrochloric acid, extracting with dichloromethane, drying an organic layer with anhydrous sodium sulfate, concentrating under vacuum condition by using a rotary evaporator to obtain a crude product, precipitating with dichloromethane/petroleum ether, centrifuging to obtain a solid, and drying in a vacuum oven for 24 h to finally obtain a white solid 2-2 (0.94 g, 72%). The nuclear magnetic hydrogen spectrum of compound 2-2 is shown in FIG. 2.

3) Synthesis of Compounds 2-3

Compound 2-2 (0.65 g, 0.98 mmol) and stannous chloride (0.26 g) were placed in a three-necked flask, 50% acetic acid solution (5 mL) and acetone (5 mL), 60%^oStirring for 12 min under C, extracting with dichloromethane after reaction, and using anhydrous organic layerDrying with sodium sulfate, concentrating the organic layer under vacuum with rotary evaporator to obtain crude product, separating and purifying the crude product with silica gel column chromatography, wherein the eluent is mixed solvent of dichloromethane and petroleum ether at volume ratio of 1:2 to obtain white solid 2-3 (0.56 g, 92%). The nuclear magnetic hydrogen spectrum of compound 2-3 is shown in FIG. 3.

4) Synthesis of Compounds 2-4

Putting the compound 2-3 (0.50 g, 0.80 mmol) into a 100 mL three-necked flask, adding a tetrahydrofuran solution (30 mL) of tetrabutylammonium fluoride (0.50 g, 1.91 mmol) and dichloromethane (30 mL), stirring at room temperature for 2h, after the reaction is finished, extracting with dichloromethane, drying an organic layer by using anhydrous sodium sulfate, concentrating the organic layer by using a rotary evaporator under vacuum conditions to obtain a crude product, and separating and purifying the crude product by using a silica gel sand core filtering mode to finally obtain a white solid 2-4 (0.35 g, 91%). The nuclear magnetic hydrogen spectrum of the compound 2-4 is shown in FIG. 4.

And performing secondary characterization on the structure of the compound 2-4 by using a time flight-electrospray ionization high-resolution mass spectrometer, and performing cross validation on the characterization result of the nuclear magnetic resonance spectrometer to show that the pterene monomeric compound 2-4 is correct again, and the high-resolution spectrum of the compound 2-4 is shown in FIG. 5.

Example 2

This example provides an amplified conjugated fluorescent porous polymer (polymer 1), the synthesis route of polymer 1 is shown below:

；

the preparation method of the polymer 1 specifically comprises the following steps:

under argon atmosphere, the compound pentadecene 2-4 (0.478 g, 1 mmol), 1, 6-dibromopyrene (0.360 g, 1 mmol) and a catalyst Pd (PPh)₃)₄(0.058 g, 0.05 mmol) and copper iodide (CuI) (0.010 g, 0.05 mmol) were reactedIn a bottle, nitrogen was evacuated three times with a double calandria, and super-dry toluene (12 mL) treated with potassium-sodium alloy and isopropylamine (K-Na alloy: (K-Na alloy) (K-Na alloy)) were addedi-Pr₂NH) (6 mL), heated to 130 deg.F^oAnd C, stirring and reacting for two days, after the reaction is finished, pouring the reaction mixture cooled to room temperature into deionized water, extracting for five times by using dichloromethane, combining organic layers, drying by using anhydrous sodium sulfate, concentrating the organic layer under the vacuum condition by using a rotary evaporator to obtain a primary concentrated crude product, filtering the crude product by using a microporous filtering device under pressure to remove catalyst residues, concentrating the crude product under the vacuum condition by using the rotary evaporator again, performing reverse precipitation in methanol to obtain a yellow-green precipitate, centrifuging to obtain the precipitate, washing the precipitate for 3 times by using the methanol, and finally drying the precipitate in a vacuum oven to obtain the light-emitting polymer yellow-green solid polymer 1 (0.325 g, 48%).

Example 3

This example provides an amplified conjugated fluorescent porous polymer (polymer 2), the synthesis route of polymer 2 is shown below:

；

the preparation method of the polymer 2 specifically comprises the following steps:

under argon atmosphere, the compound pentadecene 2-4 (0.478 g, 1 mmol), 9, 9-dioctyl-2, 7-dibromofluorene (0.760 g, 1 mmol) and a catalyst Pd (PPh)₃)₄(0.058 g, 0.05 mmol) and CuI (0.010 g, 0.05 mmol) were placed in a reaction flask, nitrogen was evacuated three times with a double-row tube, and extra dry toluene (12 mL) treated with K-Na alloy and isopropylamine (C) (N isi-Pr₂NH) (6 mL), heated to 130 deg.F^oC, stirring and reacting for two days, pouring the reaction mixture cooled to room temperature into deionized water after the reaction is finished, extracting for five times by using dichloromethane, combining organic layers, drying by using anhydrous sodium sulfate, concentrating the organic layers under the vacuum condition by using a rotary evaporator to obtain a primary concentrated crude product, filtering the crude product by using a microporous filtering device under pressure to remove catalyst residues, and recycling the rotary evaporation to obtain a productThe crude product was concentrated under vacuum and then precipitated in methanol in reverse to give a yellow-green precipitate, which was centrifuged to give a precipitate and washed 3 times with methanol, and finally dried in a vacuum oven to give the light-emitting polymer, polymer 2, a yellow-green solid (0.550 g, 51%).

Example 4

This example provides an amplified conjugated fluorescent porous polymer (polymer 3), the synthesis route of polymer 3 is shown below:

；

the preparation method of the polymer 3 specifically comprises the following steps:

under argon atmosphere, the compound pentadecene 2-4 (0.478 g, 1 mmol), 9, 10-dibromoanthracene (0.336 g, 1 mmol) and a catalyst Pd (PPh)₃)₄(0.058 g, 0.05 mmol) and CuI (0.010 g, 0.05 mmol) were placed in a reaction flask, nitrogen was evacuated three times with a double-row tube, and extra dry toluene (12 mL) treated with K-Na alloy and isopropylamine (C) (N isi-Pr₂NH) (6 mL), heated to 130 deg.F^oAnd C, stirring and reacting for two days, after the reaction is finished, pouring the reaction mixture cooled to room temperature into deionized water, extracting for five times by using dichloromethane, combining organic layers, drying by using anhydrous sodium sulfate, concentrating the organic layer under the vacuum condition by using a rotary evaporator to obtain a primary concentrated crude product, filtering the crude product by using a microporous filtering device under pressure to remove catalyst residues, concentrating the crude product under the vacuum condition by using the rotary evaporator again, performing reverse precipitation in methanol to obtain a yellow-green precipitate, centrifuging to obtain the precipitate, washing the precipitate for 3 times by using the methanol, and finally drying the precipitate in a vacuum oven to obtain a light-emitting polymer yellow-green solid polymer 3 (0.350 g, 53%).

Example 5

The embodiment provides a fluorescent sensing film, and a preparation method thereof comprises the following steps:

1) washing a quartz substrate with pure water, drying the quartz substrate by blowing, and immersing the quartz substrate in 98% H by mass fraction₂SO₄The solution and the mass fraction of the solution are 30 percent of H₂O₂In a mixed solution prepared by the solution according to the volume ratio of 3:1, heating the mixed solution to activate a quartz substrate, wherein the activation temperature is 90 ℃, the activation time is 1.5h, naturally cooling to room temperature after the activation is finished, taking out the quartz substrate from the mixed solution, washing with pure water, and drying to obtain an activated substrate;

2) mixing 3-glycidol propyl ether trimethoxy silane and toluene to prepare a silanization reagent solution (the mass concentration of the silanization reagent solution is 10%);

3) soaking the activated substrate prepared in the step 1) into the silanization reagent solution obtained in the step 2), wherein the soaking temperature is 50 ℃, the soaking time is 20 hours, taking out the substrate after soaking is finished, washing the substrate with toluene to remove the residual silanization reagent solution on the surface of the substrate, and drying the substrate to obtain the silanization substrate;

4) mixing the polymer 1 and dichloromethane to prepare a solution with the concentration of 1mol/ml, preparing a spin-coated organic polymer fluorescent coating on a silanized substrate by using a spin coater, wherein the rotation speed of the spin coater is 80 r/min, the spin-coating time is 20 min, and finally, drying in vacuum at 40 ℃ for 4 h to obtain the fluorescent sensing film.

Example 6

This example provides a fluorescence sensing film which differs from example 5 only in that polymer 1 is replaced with polymer 2 in step 4).

Example 7

This example provides a fluorescence sensing film which differs from example 5 only in that polymer 1 is replaced with polymer 3 in step 4).

Example 8

The fluorescence sensing films prepared in examples 5 to 7 were each measured using a fluorescence explosive detector, and the detection limit and response time to TNT gas are shown in table 1.

TABLE 1 detection Limit and response time test results for fluorescent sensing films on TNT gas

Polymer and method of making same	1	2	3
				Response time	1~5s	Over 20s	1~5s
Alarm min limit	1~5ng	Above 20ng	Above 5ng

From the data in the table, the polymer formed by connecting the pentacene-like rigid group and the specific group has obvious advantages for detecting TNT nitro explosives, and is an excellent improved route selection.

Example 9

When the detection limit and the response time of the fluorescent sensing film prepared in the above examples 5 to 7 are detected, the detection performance of 1ng TNT of the film can reach hundreds of times and can be stably repeated, the response time is almost instant, accurate measurement cannot be carried out, and the response time is basically less than 1 s, so that the requirement of good rapid on-site detection is met.

Example 10

The fluorescence intensity of the fluorescence sensing film prepared in the above examples 5 to 7 is tested (material adhesion test), and multiple detections show that the fluorescence intensity of the previous material is reduced with time (the adhesion of the surface material is not strongly blown away by the airflow), and after 30 detections, the fluorescence intensity of the fluorescence film is basically stable and unchanged (the bottom material is close to the rough quartz surface, the adhesion is strong, and the bottom material is not easily blown away by the airflow).

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims

1. An amplified conjugated fluorescent porous polymer having a structure represented by formula 3 to formula 5:

，

n is selected from an integer between 1 and 20.

2. The amplified conjugated fluorescent porous polymer of claim 1, wherein R is₁-R₂Identical or different, each R₁、R₂Independently selected from H, halogen, hydroxyl, cyano, amino, nitro, carboxyl and C_1-12Alkyl, -R⁵OR⁶、-OR⁵OR⁶、-OR⁵；

3. The amplified conjugated fluorescent porous polymer according to claim 1 or 2,

said C is_4-12Heteroaryl radicalSelected from the group consisting of furyl, thiophenyl, pyrrolyl, imidazolyl, pyrazolyl, thiazolyl, triazolyl, indolyl, quinolinyl, isoquinolinyl.

4. The method for preparing an enlarged conjugated fluorescent porous polymer according to any one of claims 1 to 3, comprising the steps of: carrying out coupling reaction on a compound shown in a raw material formula A and a compound shown in a raw material formula B to obtain a polymer shown in a formula 3-5;

;

、

、

；

wherein X is chlorine, bromine or iodine.

5. Use of the polymer according to any one of claims 1 to 3 or the polymer prepared by the preparation method according to claim 4 in fluorescence detection of gaseous nitro explosives, peroxide explosives, biomolecules, heavy metals and drugs.

6. Use according to claim 5, wherein the nitro-explosive is TNT, a class B explosive, octogen, hexogen or nitramine.

7. A fluorescence sensing film, which is produced by using the polymer according to any one of claims 1 to 3 or the polymer produced by the production method according to claim 4.

8. The fluorescence sensing film of claim 7, wherein the thickness of the fluorescence sensing film is 5-1000 nm.

9. Use of the fluorescence sensing film according to claim 7 or 8 for the preparation of a fluorescence sensing device.

10. The application of claim 9, wherein the fluorescence sensing device has only one detection gas path, and multiple fluorescence sensing thin film devices can be simultaneously carried in the same gas path to simultaneously test the sensing performance of multiple fluorescence sensing materials.