A method for preparing fluorescent polymer and fluorescent polymer products obtained therefrom and applications thereof

Abstract

The present invention relates to a method for preparing a fluorescent polymer and a fluorescent polymer product and application thereof, wherein a full-donor fluorescent polymer and a donor-acceptor fluorescent polymer are prepared by reacting an aryl Grignard reagent with an aryl halide. The preparation method is as follows: firstly prepare a corresponding donor-type aryl bi-Grignard reagent; then the obtained donor-type aryl bi-Grignard reagent is subjected to a coupling reaction with a tetrahydrofuran mixed solution of a donor-type or acceptor-type aryl halide, reacted at 20-60°C for 6-24 hours, and a fluorescent polymer is obtained after purification. The reactant selectivity of the present invention is high, and the occurrence of side reactions is effectively reduced. The fluorescent color of the prepared fluorescent polymer can be regulated by a donor-type or acceptor-type reaction monomer, and the fluorescent polymer has many advantages such as high regularity, strong luminescence, high quantum yield, strong heat resistance, simple process, and low cost.

Description

Technical Field

[0001] The invention relates to the field of synthesis technology, and in particular to a method for preparing a fluorescent polymer and the obtained fluorescent polymer product and application thereof. Background Art

[0002] Fluorescent materials are materials that absorb light of a certain wavelength and then emit light of different wavelengths (such as blue, green, yellow, orange and other bright colors). As one of the important branches of photofunctional materials, fluorescent materials have attracted great attention from scientists due to their high sensitivity, rich and eye-catching colors. They are also widely used in daily life and improve our quality of life. At present, fluorescent materials are widely used in fluorescent sensors, probes, bioimaging, light-emitting diodes and organic electronic devices. Conjugated polymers have excellent electrical conductivity and strong light capture ability, which can be used to amplify fluorescent sensing signals. They play an increasingly important role in disease diagnosis, photovoltaic materials and biological detection.

[0003] Fluorescent polymers have the common advantages of fluorescent small molecules and conjugated polymers. Therefore, many properties and practical applications of fluorescent small molecules are also applicable to fluorescent polymers, such as fluorescent chemical sensing, biological probes, bioimaging and optoelectronic devices. Due to the inherent properties of conjugated polymers, fluorescent polymers show superior performance in these applications than their corresponding small molecules. For example, in chemical and biological sensing applications, conjugated polymers have higher sensitivity than small molecule fluorescent probes; in the preparation of optoelectronic devices, conjugated polymers show the advantage of easier processing; the excellent stability of conjugated polymers makes them more valuable in cell imaging and even long-term tracking of cells. In addition, the easy modification of fluorescent polymers has a wider range of applications compared with small molecules. For example, by combining fluorescent materials and thermosensitive polymers, a corresponding signal with reversible fluorescence that changes with ambient temperature is achieved. Moreover, by extending their conjugated system, some fluorescent polymers have nonlinear optical properties, and because they have a rigid structure of repeating units, they can even achieve polarized luminescence. Fluorescent polymer films also have interesting functions, such as high and adjustable refractive index, photocrosslinking, etc. The three-dimensional structure gives the material a high porosity.

[0004] Early research on fluorescent polymers focused on polythiophene, polyaniline, polyfluorene, polypyrrole, polycarbazole, etc. Their unit structures are electron-rich, have relatively high energy gaps and good mobility, and are usually used as electron donors (Donor, D). Although all-donor fluorescent polymers have rich structural combinations and excellent properties, it is difficult to obtain green electrochromic materials. Since green materials should absorb blue and red light in two separate bands at the same time, materials with only a single absorption peak are difficult to achieve no matter how they are regulated. Therefore, people turned their attention to the copolymerization of electron donors (D) and electron acceptors (Accept, A) to achieve this goal.

[0005] The preparation method of fluorescent polymers is relatively simple, with high cost and complicated synthesis steps, and there is room for further improvement. The reaction of aromatic bis-Grignard reagents with aromatic dihalides has good selectivity and can generate all-donor fluorescent polymers and donor-acceptor fluorescent polymers with regular structures, making up for the defects of existing fluorescent polymers, expanding the adjustable range of fluorescent color of fluorescent polymers, and preparing fluorescent materials with high performance.

[0006] Based on the needs of industry and practical applications, it is necessary to find a method for synthesizing a new type of fluorescent polymer with better performance, simple process and low cost. Summary of the invention

[0007] The purpose of the present invention is to synthesize a linear fluorescent polymer by stepwise polymerization using a highly selective di-Grignard reagent to react with dibasic acid chlorides, dibasic esters, and dibasic nitriles, so as to solve the problems of the existing methods such as high branching degree and more side reactions.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0009] A method for preparing a fluorescent polymer comprises the following general reaction formula:

[0010]

[0011] The phenyl group in the formula also includes the exchange of thienyl, carbazolyl or fluorenyl;

[0012] X = F, Cl, Br, I;

[0013] Y = F, Cl, Br, I;

[0014] Ar includes one or more of phenyl, thienyl, benzothienyl, benzothiadiazolyl, pyridyl, and substitutions thereof containing one or more of alkyl, aryl or alicyclic groups, halogen, sulfonic acid, and nitro groups;

[0015] R' includes one or more of hydrogen, alkyl, aryl or alicyclic group, halogen, sulfonic acid group, and nitro group;

[0016] R'' includes one or more of hydrogen, alkyl, aryl or alicyclic group, halogen, sulfonic acid group, and nitro group;

[0017] The reaction product of the general reaction formula has fluorescent properties.

[0018] A fluorescent polymer is prepared by reacting an aryl Grignard reagent with an aryl halide. The fluorescent polymer has a full-donor type and a donor-acceptor type conjugated structure.

[0019] Preferably, the method comprises the following steps:

[0020] A. Obtain double Grignard reagent;

[0021] B. The aromatic dihalide is dissolved in a reaction solvent, and under the protection of an inert gas, the di-Grignard reagent is added dropwise to carry out a polymerization reaction to obtain a crude product; adding the Grignard reagent dropwise under the protection of an inert gas can prevent the di-Grignard reagent from reacting with oxygen and water in the air and affecting the normal progress of the reaction.

[0022] C. Purify the crude product to obtain a fluorescent polymer.

[0023] The fluorescent polymer prepared by the above synthesis method has a low degree of branching, and the product is a full-donor fluorescent polymer and a donor-acceptor fluorescent polymer, which has good heat resistance and luminescence, and has a high fluorescence quantum yield and conductivity. The molecular weight, structure and performance can be modified by controlling the feed ratio, reaction time, reaction temperature, raw materials and formula adjustment, and can also be regulated by selecting different substituents to obtain a modified fluorescent polymer to regulate its solubility, softness, film-forming property, luminescent color and heat resistance and other properties.

[0024] Preferably, the aryl di-Grignard reagent includes one or more of o-, p-, m-phenyl di-Grignard reagents or thienyl or carbazole or fluorenyl di-Grignard reagents, and the halogen contained includes one of chlorine, bromine and iodine. The aryl di-Grignard reagent can be an aryl di-Grignard reagent containing an alkyl, aryl or alicyclic group, halogen, sulfonic acid group, or nitro substituent on the aromatic ring.

[0025] Preferably, the aryl dihalide is one or more of o-, p-, m-phenyl dihalide, naphthyl, fluorenyl, pyridyl, and thienyl dihalide, the halogen of the binary halide is one or more of chlorine, bromine, and iodine, and the aryl dihalide can be an aryl dihalide containing alkyl, aryl or alicyclic groups, halogen, sulfonic acid, or nitro substituents on the benzene ring.

[0026] Preferably, the operation of step A comprises: mixing iodine particles, aromatic dihalide and magnesium powder in a reaction solvent, and heating and performing ultrasonic reaction under the protection of an inert gas to obtain the double Grignard reagent.

[0027] Preferably, in step A, the molar ratio of the aromatic dihalide to the magnesium powder is 1:3; the reaction temperature of the ultrasonic reaction is 20° C. to 50° C., the reaction time is 20 to 60 min, and the ultrasonic power is 300 to 1500 W.

[0028] Preferably, the inert gas includes one or more of nitrogen and argon; and the reaction solvent includes tetrahydrofuran.

[0029] Preferably, in step B, the dropping process of the di-Grignard reagent includes slow dropping and rapid stirring, and the dropping time includes 0.1 to 1 hour; the reaction temperature of the polymerization reaction includes 20 to 60° C., and the reaction time includes 6 to 24 hours.

[0030] The double Grignard reagent needs to be added slowly and stirred quickly, with a total addition time of 0.1 to 1 hour being appropriate. This can prevent the reaction from being too intense and better control the reaction process.

[0031] Preferably, the purification treatment in step C includes: adding a quencher (alcohol solvent, organic acid or water) to the crude product for quenching, removing the solvent, dissolving and washing alternately with water, alcohol solvent and halogenated alkane in sequence, precipitating in an alcohol solvent, and drying to obtain the fluorescent polymer.

[0032] Preferably, in step C, the quenching agent includes one or more of methanol, ethanol, butanol, formic acid, acetic acid, butyric acid, and water; the alcohol solvent includes one or more of methanol, ethanol, and butanol; the halogenated alkane includes one or more of chloroform, dichloromethane, dichloroethane, and carbon tetrachloride; and the means for removing the solvent includes distillation.

[0033] A fluorescent polymer product obtained by the method for preparing a fluorescent polymer, the fluorescent polymer product comprises one or more of a fluorescent polymer with a full-donor conjugated structure and a fluorescent polymer with a donor-acceptor conjugated structure.

[0034] Fluorescent polymers with all-donor conjugated structures and fluorescent polymers with donor-acceptor conjugated structures can have stronger luminescence properties and can be used in certain fields with special needs.

[0035] When preparing a fully donor fluorescent polymer, the aryl Grignard reagent is an aryl di-Grignard reagent, and the aryl di-Grignard reagent includes one or more of phenyl, thienyl, carbazole or fluorenyl di-Grignard reagents, and the halogen contained includes one of fluorine, chlorine, bromine and iodine. The di-Grignard reagent can be an aryl di-Grignard reagent containing alkyl, aryl or alicyclic groups, halogen, sulfonic acid group, nitro substituents on the aromatic ring. The aryl dihalide is one or more of the ortho, para and meta dihalides of phenyl, thienyl, carbazole, pyridyl, fluorenyl dihalides, and the halogenated compound is one of fluorine, chlorine, bromine and iodine.

[0036] When preparing a donor-acceptor type fluorescent polymer, the aryl Grignard reagent is an aryl di-Grignard reagent, the aryl dihalide is one or more of phenyl, naphthyl, benzothiophenyl, and benzothiadiazolyl, and the halogen is one of fluorine, chlorine, bromine, and iodine. The aryl di-Grignard reagent or aryl di-halide may contain an alkyl, aryl, or alicyclic group, halogen, sulfonic acid group, or nitro group on the aromatic ring.

[0037] An application of the fluorescent polymer product is used for one or more of luminescence, light capture, conductivity, solar cells, preparation of disease diagnosis equipment or preparations, and preparation of biological detection equipment or preparations.

[0038] The obtained fluorescent polymer has good luminescence and heat resistance, strong light capture ability and conductivity, and is mainly used as photovoltaic materials, fluorescent sensor signal amplification materials in the biomedical field, solar cells, and conductive materials. It has applications in the fields of fluorescent sensors, probes, biological imaging, light-emitting diodes, and organic electronic devices.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] The present invention relates to a new method for preparing a fluorescent polymer, wherein a full-donor fluorescent polymer and a donor-acceptor fluorescent polymer are prepared by reacting an aryl Grignard reagent with an aryl halide. The preparation method comprises the following steps: firstly preparing a corresponding donor-type aryl bi-Grignard reagent; then subjecting the prepared donor-type aryl bi-Grignard reagent to a coupling reaction with a tetrahydrofuran mixed solution of a donor-type or acceptor-type aryl halide, reacting at 20 to 60°C for 6 to 24 hours, and obtaining a fluorescent polymer after purification. The present invention has high selectivity of reactants, effectively reduces the occurrence of side reactions, and the fluorescent color of the prepared fluorescent polymer can be regulated by a donor-type or acceptor-type reaction monomer, and has many advantages such as high regularity, strong luminescence, high quantum yield, strong heat resistance, simple process, low cost, etc.

[0041] The present invention can prepare the corresponding aryl di-Grignard reagent by using aryl dihalide as raw material, react the prepared aryl di-Grignard reagent with one or more tetrahydrofuran solutions of aryl dihalide to prepare a crude fluorescent polymer product, and obtain a refined fluorescent polymer after purification.

[0042] The substituent of the aryl halide may be in one or more of the para, ortho or meta positions; the phenyl group may be substituted by a thienyl group, a carbazole group or a fluorenyl group, and the aryl halide may also contain substituents such as an alkyl group, an aryl group or an alicyclic group, a halogen group, a sulfonic acid group, a nitro group, etc.;

[0043] The invention can prepare linear or hyperbranched fluorescent polymers with high regularity under mild conditions due to the simple preparation process of the aromatic Grignard reagent, high activity and good selectivity. Fluorescent polymers with different molecular weights, structures and properties can be prepared by controlling the reaction temperature, time, feed ratio and substrate selection.

[0044] The invention prepares fluorescent polymers by using aromatic di-Grignard reagents and aromatic dihalides, and the reaction conditions are mild, and the reaction can be carried out at room temperature and normal pressure, and the reaction time is short; since high temperature and high pressure are not involved, the operation is simple; the reactants are halogenated hydrocarbons, which are easy to purchase, store and transport. The reactants have high selectivity, and highly regular all-donor fluorescent polymers and donor-acceptor fluorescent polymers are prepared, which have excellent photoelectric properties, heat resistance and crystallinity. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 The infrared spectrum of poly (2,5-dimethoxy-1,4-phenylene-3,4-ethylenedioxy-2,5-thienylene) prepared by using 2,5-dibromo-3,4-ethylenedioxythiophene in the present invention;

[0046] Figure 2 The poly{carbonyl-1,4-[bis(1,4-phenylene)]naphthylene} prepared by using 4,4'-dibromobenzophenone of the present invention 1 H-NMR spectrum;

[0047] Figure 3 The thermal weight loss curve of poly[2-(2,5-dimethyl-1,4-phenylene)-3,6-thiophene[3,2-b]thienyl] prepared by using 3,6-dibromothiophene[3,2-b]thiophene in the present invention;

[0048] Figure 4 This is the GPC spectrum of poly (9,9-dimethyl-2,7-fluorenylene-4,7-phenylene-2,1,3-benzothiadiazole) prepared by using 4,7-dibromo-2,1,3-benzothiadiazole in the present invention. DETAILED DESCRIPTION

[0049] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings.

[0050] Example 1

[0051] Add 2.36 g of p-dibromobenzene, 1 iodine, and 30 mL of tetrahydrofuran to a dry Schlenk bottle, evacuate and replace with argon three times, and ultrasonically heat at 45 °C for 30 min to prepare p-dibromobenzene double Grignard reagent. Add 3.26 g of 2,5-dibromo-3-hexylthiophene, 40.65 mg of NiCl 2 (dppp), 30 mL tetrahydrofuran, vacuum and replace argon 3 times. Slowly add dibromobenzene diGrignard reagent to the three-necked flask, stir rapidly, and react at room temperature for 8 hours. Add 40 mL of anhydrous methanol solution to the three-necked flask and stir at room temperature for 1 hour. Evaporate to dryness. Wash with water and methanol, extract with methanol for 24 hours, and dry. Add a small amount of chloroform to dissolve and precipitate in methanol. Filter and dry. The fluorescent polymer is obtained.

[0052] The number average molecular weight of the fluorescent polymer prepared in this example is 21220 g / mol, and the weight average molecular weight is 35340 g / mol.

[0053] Example 2

[0054] In a dry Schlenk bottle, add 3.58 g of 1,4-diiodo-2,5-dimethylbenzene, 1 iodine, and 30 mL of tetrahydrofuran, evacuate and replace with argon three times, and ultrasonically heat at 30 °C for 25 min to prepare 1,4-diiodo-2,5-dimethylbenzene bis-Grignard reagent. In a dry three-necked bottle, add 2.98 g of 2,6-dibromothiophene[3,2-b]thiophene, 81.30 mg of NiCl 2 (dppp), 60 mL tetrahydrofuran, vacuum and replace argon 3 times. Slowly add 1,4-diiodo-2,5-dimethylbenzene diGrignard reagent to the three-necked flask, stir rapidly, and react at 50 ℃ for 24 hours. Add 40 mL of anhydrous ethanol solution to the three-necked flask and stir at room temperature for 1 hour. Evaporate to dryness. Wash with water and methanol, extract with methanol for 24 hours, and dry. Add a small amount of chloroform to dissolve and precipitate in methanol. Filter and dry. The fluorescent polymer is obtained.

[0055] The conjugated polymer prepared in this example has a temperature of 423°C when losing 5% of its weight and a temperature of 522°C when losing 50% of its weight, and has good heat resistance. The fluorescent polymer prepared in this example has a number average molecular weight of 24310 g / mol and a weight average molecular weight of 37250 g / mol.

[0056] Example 3

[0057] Add 2.96 g 1,4-dibromo-2,5-dimethoxybenzene, 1 iodine, and 30 mL tetrahydrofuran to a dry Schlenk bottle, evacuate and replace with argon three times, and ultrasonically heat at 50°C for 45 min to prepare 2.96 g 1,4-dibromo-2,5-dimethoxybenzene bis-Grignard reagent. Add 2.99 g 2,5-dibromo-3,4-ethylenedioxythiophene, 40.65 mg NiCl 2 (dppp), 60 mL tetrahydrofuran, vacuum and replace argon 3 times. Slowly drop 2.96 g 1,4-dibromo-2,5-dimethoxybenzene di-Grignard reagent into the three-necked flask, stir rapidly, and react at room temperature for 14 h. Add 40 mL acetic acid solution to the three-necked flask and stir at room temperature for 1 h. Evaporate to dryness. Wash with water and methanol, extract with methanol for 24 h, and dry. Add a small amount of dichloromethane to dissolve and precipitate in methanol. Filter and dry. The fluorescent polymer is obtained.

[0058] The number average molecular weight of the fluorescent polymer prepared in this example is 43420 g / mol, and the weight average molecular weight is 77650 g / mol.

[0059] Example 4

[0060] Add 2.96 g 1,4-dibromo-2,5-dimethoxybenzene, 1 iodine, and 20 mL tetrahydrofuran to a dry Schlenk bottle, evacuate and replace with argon three times, and ultrasonically heat at 50 °C for 45 min to prepare 1,4-dibromo-2,5-dimethoxybenzene bis-Grignard reagent. Add 2.78 g 4,7-dibromobenzofurazan, 40.65 mg NiCl 2 (dppp), 60 mL tetrahydrofuran, vacuum and replace argon 3 times. Slowly add 1,4-dibromo-2,5-dimethoxybenzene diGrignard reagent to the three-necked flask, stir rapidly, and react at 50 °C for 24 h. Add 40 mL butanol to the three-necked flask and stir at room temperature for 1 h. Evaporate to dryness. Wash with water and methanol, extract with methanol for 24 h, and dry. Add a small amount of dichloroethane to dissolve and precipitate in methanol. Filter and dry. The fluorescent polymer is obtained.

[0061] The fluorescent polymer prepared in this example has a number average molecular weight of 31310 g / mol and a weight average molecular weight of 51750 g / mol.

[0062] Example 5

[0063] Add 2.86 g 1,4-dibromonaphthalene, 1 iodine, and 30 mL tetrahydrofuran to a dry Schlenk bottle, evacuate and replace with argon three times, and ultrasonically heat at 45 °C for 45 min to prepare 1,4-dibromonaphthalene double Grignard reagent. Add 3.40 g 4,4'-dibromobenzophenone, 4.05 g FeCl 3 , 3.5 mL TEMED, 60 mL tetrahydrofuran, vacuum and replace argon three times. Slowly drop 1,4-dibromonaphthalene di-Grignard reagent into the three-necked flask, stir rapidly, and react at 25 °C for 20 h. Add 40 mL water to the three-necked flask and stir at room temperature for 1 h. Evaporate to dryness. Wash with water and methanol, and filter. Add N,N-dimethylformamide to dissolve, and precipitate in petroleum ether. Filter and dry. The fluorescent polymer is obtained.

[0064] The fluorescent polymer prepared in this example has a number average molecular weight of 8510 g / mol and a weight average molecular weight of 15140 g / mol.

[0065] Example 6

[0066] Add 3.52 g 9,9-dimethyl-2,7-dibromofluorene, 1 iodine, and 30 mL tetrahydrofuran to a dry Schlenk bottle, evacuate and replace with argon three times, and ultrasonically heat at 50°C for 40 min to prepare 9,9-dimethyl-2,7-dibromofluorene double Grignard reagent. Add 2.94 g 4,7-dibromo-2,1,3-benzothiadiazole, 81.30 mg NiCl to a dry three-necked flask. 2 (dppp), 60 mL tetrahydrofuran, vacuum and replace argon 3 times. Slowly add 9,9-dimethyl-2,7-dibromofluorene bis-Grignard reagent to the three-necked flask, stir rapidly, and react at 50 °C for 24 h. Add 40 mL of anhydrous methanol solution to the three-necked flask and stir at room temperature for 1 h. Evaporate to dryness. Wash with methanol, extract with methanol for 24 h, and dry. Add a small amount of chloroform to dissolve and precipitate in methanol. Filter and dry. The fluorescent polymer is obtained.

[0067] The fluorescent polymer prepared in this example has a number average molecular weight of 63270 g / mol and a weight average molecular weight of 106450 g / mol.

[0068] In Examples 1-6, phenyl dihalide, biphenyl dihalide, and fluorenyl dihalide can be replaced with each other. Phenyl dihalide, fluorenyl dihalide, thienyl dihalide, and carbazolyl dihalide can be replaced with each other.

[0069] Effect Example 1

[0070] Taking the samples prepared in Examples 1, 3, and 4 as examples, fluorescence intensity tests were carried out, using 309 nm, 366 nm, and 369 nm as excitation wavelengths, respectively. All three samples emitted strong fluorescence. The maximum emission wavelength range of the sample in Example 1 was from 414 nm to 424 nm, the maximum emission wavelength range of Example 3 was from 519 nm to 541 nm, and the maximum emission wavelength range of Example 4 was from 519 nm to 541 nm.

[0071] Poly(2,5-dimethoxy-1,4-phenylene-3,4-ethylenedioxy-2,5-thienylene), poly{carbonyl-1,4-[bis(1,4-phenylene)]naphthylene}, poly[2-(2,5-dimethyl-1,4-phenylene)-3,6-thienylene[3,2-b]thienyl], poly(9,9-dimethyl-2,7-fluorenylene-4,7-phenylene-2,1,3-benzothiadiazole) etc. prepared by the method described in Examples 1-6 were subjected to infrared, 1 H-NMR, TGA, GPC characterization, such as Figure 1-4 As shown. Figure 1 The infrared spectrum of the prepared poly (2,5-dimethoxy-1,4-phenylene-3,4-ethylenedioxy-2,5-thienylene) can confirm the structure; according to Figure 2 The NMR spectrum of the prepared poly{carbonyl-1,4-[bis(1,4-phenylene)]naphthylene} can confirm the structure; according to Figure 3 The thermal decomposition temperature shows that the prepared poly[2-(2,5-dimethyl-1,4-phenylene)-3,6-thienylene[3,2-b]thienyl] has good heat resistance; Figure 4 The molecular weight of poly(9,9-dimethyl-2,7-fluorenylene-4,7-phenylene-2,1,3-benzothiadiazole) showed a unimodal distribution, indicating that there was only one reaction mechanism for the preparation of poly(9,9-dimethyl-2,7-fluorenylene-4,7-phenylene-2,1,3-benzothiadiazole) by this method, which was beneficial to the control of the reaction.

[0072] The above disclosure is only the preferred embodiment of the present invention, which cannot be used to limit the scope of the present invention. Therefore, equivalent changes made according to the claims of the present invention are still within the scope of the present invention.

Claims

1. A method for preparing a fluorescent polymer, characterized in that: The reaction formula includes the following: The phenyl group in the formula also includes the exchange of thienyl, carbazolyl or fluorenyl; X = F, Cl, Br, I; Y = F, Cl, Br, I; Ar includes one or more of phenyl, thienyl, benzothienyl, benzothiadiazolyl, pyridyl, and substitutions thereof containing one or more of alkyl, aryl or alicyclic groups, halogen, sulfonic acid, and nitro groups; R' includes one or more of hydrogen, alkyl, aryl or alicyclic group, halogen, sulfonic acid group, and nitro group; R'' includes one or more of hydrogen, alkyl, aryl or alicyclic group, halogen, sulfonic acid group, and nitro group; The reaction product of the general reaction formula has fluorescent properties.

2. The method for preparing a fluorescent polymer according to claim 1, characterized in that: The steps include: A. Obtain double Grignard reagent; B. dissolving the aromatic dihalide in a reaction solvent, and under the protection of an inert gas, dropwise adding the di-Grignard reagent to carry out a polymerization reaction to obtain a crude product; C. Purify the crude product to obtain a fluorescent polymer.

3. The method for preparing a fluorescent polymer according to claim 2, characterized in that: The operation of step A comprises: mixing iodine particles, aromatic dihalide and magnesium powder in a reaction solvent, and heating and performing ultrasonic reaction under the protection of an inert gas to obtain the double Grignard reagent.

4. The method for preparing a fluorescent polymer according to claim 3, characterized in that: In step A, the molar ratio of the aromatic dihalide to the magnesium powder is 1:3; the reaction temperature of the ultrasonic reaction is 20° C. to 50° C., the reaction time is 20 to 60 min, and the ultrasonic power is 300 to 1500 W.

5. The method for preparing a fluorescent polymer according to claim 2 or 3, characterized in that: The inert gas includes one or more of nitrogen and argon; the reaction solvent includes tetrahydrofuran.

6. The method for preparing a fluorescent polymer according to claim 2, characterized in that: In step B, the process of adding the double Grignard reagent includes slow addition and rapid stirring; the reaction temperature of the polymerization reaction is 20-60° C., and the reaction time is 6-24 hours.

7. The method for preparing a fluorescent polymer according to claim 2, characterized in that: The purification treatment in step C includes: adding a quencher to the crude product for quenching, removing the solvent, dissolving and washing alternately with water, alcohol solvent and halogenated alkane in sequence, precipitating in an alcohol solvent, and drying to obtain the fluorescent polymer.

8. The method for preparing a fluorescent polymer according to claim 7, characterized in that: In step C, the quenching agent includes one or more of methanol, ethanol, butanol, formic acid, acetic acid, butyric acid, and water; the alcohol solvent includes one or more of methanol, ethanol, and butanol; the halogenated alkane includes one or more of chloroform, dichloromethane, dichloroethane, and carbon tetrachloride; and the means for removing the solvent includes distillation.

9. A fluorescent polymer product obtained by the method for preparing a fluorescent polymer according to claim 1, characterized in that: The fluorescent polymer product includes one or more of a fluorescent polymer with a full donor type conjugated structure and a fluorescent polymer with a donor-acceptor type conjugated structure.

10. An application of the fluorescent polymer product as claimed in claim 9, characterized in that: Used for one or more of luminescence, light capture, conduction, solar cells, preparation of disease diagnosis equipment or preparations, preparation of biological detection equipment or preparations.

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