(Benzene-thiophene) derivative conjugated polymer and application thereof

Abstract

The invention discloses a (benzene-thiophene) derivative conjugated polymer, and relates to an organic photoelectric material. According to the preparation method, the (benzene-thiophene) derivative monomer is prepared through the coupling reaction, then the (benzene-thiophene) derivative conjugated polymer is prepared through the direct arylation polycondensation reaction, the transmittance, coloring efficiency, response time and other properties of the polymer are optimized, and the preparation method has important guiding significance on electrochromic application of the polymer. The invention discloses a preparation method of a (benzene-thiophene) derivative conjugated polymer, the polymer material is prepared through direct arylation condensation polymerization, the structural formula of the polymer material is shown in the specification, R1 is H,-C6H13 and-OC6H13 straight chains, R2 is-C6H13 and-C8H17 straight chains, and n is a natural number of 1-10000. According to the series of conjugated polymers, the side chain structure is changed, so that the optical contrast and coloring efficiency of electrochromism are improved.

Description

Technical Field

[0001] This invention relates to organic optoelectronic materials, particularly the application of (benzene-thiophene) derivative conjugated polymers in the field of electrochromism. Background Technology

[0002] Electrochromic materials are materials whose optical properties change stably and reversibly under the influence of an applied electric field, resulting in changes in color or transparency. These materials have already achieved commercial applications in fields such as electronic displays, building energy conservation, military security, aerospace, and 3C products. The global electrochromic materials market is projected to reach 22.51 billion yuan by 2030, with a compound annual growth rate of 7.14%. The electrochromic field is full of both tremendous opportunities and challenges.

[0003] Conjugated polymers, as typical electrochromic materials, have attracted widespread attention from researchers due to their advantages such as light weight, rich colors, ease of synthesis, and simple fabrication of corresponding devices. Researchers have been working to improve the electron transport performance of electrochromic materials through strategies such as chemical structure design and thin film morphology optimization, and to enhance their ion transport performance by constructing cross-linked structures and preparing intrinsically porous polymers. Improvements in electron and ion transport performance can effectively improve key properties of electrochromic materials and devices, such as response speed, coloring efficiency, and cycle stability, thereby enhancing the overall performance of the devices. (Benzene-thiophene) derivative conjugated polymers possess many excellent properties, including high coloring efficiency, rich color changes, and good stability, thus attracting widespread attention. Furthermore, the benzene and thiophene rings can be easily functionalized through substituents to adjust the polymer's solubility, molecular planarity, and HOMO / LUMO energy levels. Currently, a series of (benzene-thiophene) derivative conjugated polymers have been reported in the field of electrochromism, but the structure-activity relationship between the polymer side chain structure and electrochromic performance is unclear, necessitating further research. Summary of the Invention

[0004] This invention addresses the shortcomings of existing technologies by researching methods for preparing (benzene-thiophene) derivative conjugated polymers and exploring their applications in electrochromic processes. This series of conjugated polymers, by altering the side chain structure of the benzene and thiophene rings, improves the optical contrast and color development efficiency of electrochromic processes, representing a novel type of electrochromic functional layer material.

[0005] This invention is achieved through the following technical solution:

[0006] A first aspect of the present invention provides a (benzene-thiophene) derivative conjugated polymer, characterized in that it has the following structure:

[0007]

[0008] Where R1 is H, -C6H 13 -OC6H 13 Straight chain, R2 is -C6H 13 -C8H 17 A straight chain, where n is a natural number from 1 to 10000.

[0009] A second aspect of the present invention provides a method for preparing the above-mentioned (benzene-thiophene) derivative conjugated polymer, comprising the following steps:

[0010]

[0011] A direct arylation polycondensation reaction was carried out with a certain molar ratio of (benzene-thiophene) derivative monomers and 3,4-dialkoxythiophene dibromo monomers, along with a certain proportion of terpentine, palladium acetate, potassium carbonate, and dimethylacetamide, to obtain a conjugated polymer. Wherein, R1 is H,-C6H. 13 -OC6H 13 Straight chain, R2 is -C6H 13 -C8H 17 Straight chain.

[0012] Preferably, in the above steps, the molar mass ratio of the (benzene-thiophene) derivative monomer to the 3,4-dialkoxythiophene dibromo monomer is 1:1.

[0013] Preferably, in the above steps, the direct arylation polycondensation reaction is as follows: under a nitrogen atmosphere, a certain molar mass ratio of (benzene-thiophene) derivative monomer and 3,4-dialkoxythiophene dibromo monomer, as well as a certain proportion of terpentine, palladium acetate, and potassium carbonate are dissolved in dimethylacetamide, and the mixture is heated to 120 °C and refluxed for 24 hours.

[0014] A third aspect of the present invention provides a method for preparing the (benzene-thiophene) derivative monomer required for the above-mentioned conjugated polymer, comprising the following steps:

[0015]

[0016] Where R1 is H, -C6H 13 -OC6H 13 Straight chain.

[0017] A coupling reaction was carried out in toluene with a certain molar ratio of dibromobenzene derivative, tin-butyl EDOT and tetra-triphenylphosphine palladium to obtain (benzene-thiophene) derivative monomer.

[0018] Preferably, in the above steps, the molar ratio of the dibromobenzene derivative to tin-butyl EDOT is 1:2.1.

[0019] Preferably, in the above steps, the coupling reaction is as follows: under a nitrogen atmosphere, a certain molar ratio of dibromobenzene derivative, tin-butyl EDOT, and tetra-triphenylphosphine palladium are dissolved in toluene, and the mixture is heated to 120 °C and refluxed for 12 hours.

[0020] A fourth aspect of the present invention provides the application of the above-described conjugated polymer in the field of electrochromism. Attached Figure Description

[0021] Figure 1 It has a (benzene-thiophene) derivative polymer structure.

[0022] Figure 2 The 1H NMR spectrum of monomer 1, a (benzene-thiophene) derivative.

[0023] Figure 3 The 1H NMR spectrum of monomer 2, a (benzene-thiophene) derivative.

[0024] Figure 4 The images show the spectroelectrochemical spectra of (benzene-thiophene) derivative conjugated polymers P1 and P2.

[0025] Figure 5 The kinetic curves are for (benzene-thiophene) derivative conjugated polymers P1 and P2. Detailed Implementation

[0026] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0027] To enable those skilled in the art to better understand the technical solutions of this application, the technical solutions of this application will be described in detail below with reference to specific embodiments. Unless otherwise specified, experimental conditions not detailed in the embodiments are generally based on conventional conditions or conditions recommended by the reagent company; reagents, consumables, etc., used in the following embodiments can be obtained commercially unless otherwise specified. Example

[0028] Preparation of (benzene-thiophene) derivative conjugated polymer P1

[0029] The chemical reaction process is shown below, with specific reaction steps and conditions as follows:

[0030]

[0031] Under nitrogen protection, monomer 1 (600 mg, 1.14 mmol) of the (benzene-thiophene) derivative was added to a pressure-resistant flask along with 3,4-dihexyloxythiophene dibromide (566 mg, 1.14 mmol), pentylamino acid (34.91 mg, 0.34 mmol), palladium acetate (3.22 mg, 0.023 mmol), and potassium carbonate (393.53 mg, 2.85 mmol). 10 mL of N,N-dimethylacetamide was added, and the mixture was stirred until homogeneous. The mixture was then refluxed at 120 °C for 24 h. After cooling to room temperature, 100 mL of anhydrous methanol was added, and the mixture was filtered through filter paper to obtain a red precipitate. The polymer was then extracted sequentially with anhydrous methanol and n-hexane using a Soxhlet extractor. Finally, the polymer was recrystallized from chloroform and anhydrous methanol in 75% yield.

[0032] Example 2

[0033] Preparation of (benzene-thiophene) derivative conjugated polymer P2

[0034] The chemical reaction process is shown below, with specific reaction steps and conditions as follows:

[0035]

[0036] Under nitrogen protection, monomer 2 (600 mg, 1.68 mmol) of the (benzene-thiophene) derivative was added to a pressure-resistant flask along with 3,4-dihexyloxythiophene dibromide (831 mg, 1.68 mmol), pentylamino acid (51.33 mg, 0.50 mmol), palladium acetate (4.76 mg, 0.034 mmol), and potassium carbonate (579.94 mg, 4.20 mmol). N,N-dimethylacetamide (10 mL) was added, and the mixture was stirred until homogeneous. The mixture was then refluxed at 120 °C for 24 h. After cooling to room temperature, 100 mL of anhydrous methanol was added, and the mixture was filtered through filter paper to obtain a red precipitate. The polymer was then extracted sequentially with anhydrous methanol and n-hexane using a Soxhlet extractor. Finally, the polymer was recrystallized from chloroform and anhydrous methanol in 75% yield.

[0037] Example 3

[0038] Preparation of (benzene-thiophene) derivative monomer 1

[0039] A coupling reaction was carried out in a specific molar ratio of dibromobenzene derivative, tin-butyl-3,4-dialkoxythiophene, and tetratetraphenylphosphine palladium to obtain a (benzene-thiophene) derivative monomer. R1 is H,-C6H. 13 -OC6H 13 Straight chain.

[0040] The chemical reaction process is shown below, with specific reaction steps and conditions as follows:

[0041]

[0042] Under nitrogen protection, dibromobenzene derivative (1.0 g, 2.49 mmol), tin-butyl EDOT (2.26 g, 5.22 mmol), and tetrakis(triphenylphosphine)palladium (28.9 mg, 0.025 mmol) were added to a pressure-resistant flask, followed by the addition of toluene (10 mL). The mixture was stirred thoroughly and heated to reflux at 120 °C for 12 h. After cooling to room temperature, the toluene solvent was removed by vacuum distillation to obtain the crude product. The crude product was purified by silica gel column chromatography with 300-mesh silica gel as the stationary phase and a mixed solvent of petroleum ether and dichloromethane as the mobile phase to obtain (benzene-thiophene) derivative monomer 1. Nuclear magnetic resonance (NMR) spectra were then analyzed. Figure 2 ).

[0043] Example 4

[0044] Preparation of (benzene-thiophene) derivative monomer 2

[0045] The chemical reaction process is shown below, with specific reaction steps and conditions as follows:

[0046]

[0047] Under nitrogen protection, dibromobenzene derivative (1.0 g, 4.27 mmol), tin-butyl EDOT (3.88 g, 8.97 mmol), and tetraphenylphosphine palladium (49.71 mg, 0.043 mmol) were added to a pressure-resistant flask, followed by the addition of toluene (10 mL). The mixture was stirred thoroughly and heated to reflux at 120 °C for 12 h. After cooling to room temperature, the toluene solvent was removed by vacuum distillation to obtain the crude product. The crude product was purified by silica gel column chromatography with 300-mesh silica gel as the stationary phase and a mixed solvent of petroleum ether and dichloromethane as the mobile phase to obtain (benzene-thiophene) derivative monomers. Nuclear magnetic resonance (NMR) spectra were then analyzed. Figure 3 ).

[0048] Example 5

[0049] Taking the polymer materials obtained in Examples 1 and 2 as examples, their application in the field of electrochromic materials.

[0050] The following examples will illustrate the polymer provided by the present invention and its application process in the field of electrochromic technology, but the present invention is not limited to the examples given.

[0051] (1) Spectroelectrochemistry

[0052] The polymers obtained in Examples 1 and 2 were sprayed onto ITO conductive glass to form a polymer film. The ITO conductive glass coated with the polymer film was placed in a three-electrode electrolytic cell containing an acetonitrile solution of tetrabutylammonium hexafluoride. The working electrode was the ITO conductive glass with the polymer film, the counter electrode was a platinum sheet, and the reference electrode was an Ag / AgCl electrode. Using a potentiostatic method, the voltage applied to the working electrode was adjusted by an electrochemical workstation, and the changes in the absorption spectrum of the polymer at different voltages were recorded using a UV-Vis spectrometer, thus obtaining the spectroelectrochemical spectrum of the polymer. Figure 4 ).

[0053] (2) Dynamics

[0054] The transmittance of a polymer film in its oxidized and reduced states at a specific wavelength under a square wave potential was measured using a UV-Vis spectrophotometer, thereby calculating optical contrast, response time, etc. The UV-Vis spectrophotometer records a time-transmittance curve, while the electrochemical workstation records a time-current curve. The coloring efficiency can also be calculated from these two curves. Figure 5 .

[0055] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A (benzene-thiophene) derivative conjugated polymer, characterized in that, It has the following structure: ， Where R1 is H, -C6H 13 -OC6H 13 Straight chain, R2 is -C6H 13 -C8H 17 A straight chain, where n is a natural number from 1 to 10000.

2. The method for preparing the conjugated polymer according to claim 1, characterized in that, A direct arylation polycondensation reaction was carried out with a certain molar ratio of (benzene-thiophene) derivative monomers and 3,4-dialkoxythiophene dibromide, along with a certain proportion of terpentine, palladium acetate, potassium carbonate, and dimethylacetamide, to obtain a conjugated polymer. Wherein, R1 is H,-C6H. 13 -OC6H 13 Straight chain, R2 is -C6H 13 -C8H 17 Straight chain 。 3. The method for preparing the (benzene-thiophene) derivative monomer according to claim 2, characterized in that, A coupling reaction was carried out with a certain molar ratio of dibromobenzene derivative, tin-butyl EDOT, and tetratetraphenylphosphine palladium to obtain a (benzene-thiophene) derivative monomer, wherein R1 is H,-C6H. 13 -OC6H 13 Straight chain 。

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