A polymer semiconductor material containing benzene or pyridine acetylene group triphenylamine and a hole transport material and application formed by cross-linking thereof

Abstract

The application belongs to the field of polymer semiconductor materials, and discloses a polymer semiconductor material containing benzene or pyridine acetylene group triphenylamine and a hole transport material formed by cross-linking of the polymer semiconductor material and applications. The polymer semiconductor material has the structure shown in the following formula (I) or formula (II), and the polymer semiconductor material can be subjected to a "sulfhydryl-alkyne" click chemistry reaction with a small molecule containing sulfhydryl to obtain a cross-linked polymer hole transport material. The polymer semiconductor material has a relatively suitable HOMO energy level, and through the "sulfhydryl-alkyne" click chemistry reaction with a small molecule containing sulfhydryl cross-linking agent, a relatively low cross-linking temperature and a relatively high hole mobility can be achieved, and the polymer semiconductor material has a broad commercial prospect in the fields of optoelectronic semiconductor materials such as organic light-emitting diodes, organic solar cells, organic field effect transistors and perovskite solar cells.

Description

Technical Field

[0001] This invention belongs to the field of polymer semiconductor materials, and specifically relates to a polymer semiconductor material containing benzene or pyridine ethynyltriphenylamine, a hole transport material formed by crosslinking thereof, and its applications. Background Technology

[0002] Organic light-emitting diodes (OLEDs) are widely used in display and lighting fields due to their self-emissive nature, wide viewing angle, low driving voltage, thin and light device, ease of large-area fabrication, and flexibility.

[0003] OLED devices primarily consist of an ITO anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and a metal cathode. The main methods for fabricating these functional layers are vacuum evaporation and solution processing. Vacuum evaporation is suitable for fabricating small-sized thin films, producing uniform and dense films with precise thickness control, making it the primary fabrication process for commercial OLEDs. In contrast, solution processing offers advantages in improving material utilization, simplifying device fabrication processes, and fabricating large-area devices, making it commercially viable. However, interlayer miscibility in solution processing can damage the functional layers. Using cross-linked hole transport materials, the resulting cross-linked films exhibit solvent resistance, resolving the interlayer miscibility issue and meeting the requirements for solution-based OLED fabrication.

[0004] Current cross-linked hole transport materials suffer from drawbacks such as high cross-linking temperature and low hole mobility, which lead to poor device performance and limit their commercial application. Therefore, developing cross-linked polymer hole transport materials with low cross-linking temperature and high mobility is a current research hotspot. Summary of the Invention

[0005] In order to overcome the shortcomings and deficiencies of the prior art, the primary objective of this invention is to provide a polymer semiconductor material containing benzene or pyridine ethynyltriphenylamine.

[0006] Another object of the present invention is to provide a method for preparing the above-mentioned polymer semiconductor material containing benzene or pyridine ethynyltriphenylamine.

[0007] Another object of the present invention is to provide a crosslinked polymer hole transport material obtained by the "thiol-yne" click chemical reaction of the above polymer semiconductor material containing phenyl or pyridyl ethynyl triphenylamine and a small molecule containing a thiol group. The polymer semiconductor material containing phenyl or pyridyl ethynyl triphenylamine has a relatively appropriate HOMO energy level. By undergoing the "thiol-yne" click chemical reaction with a small molecule crosslinking agent containing a thiol group, it can achieve a relatively low crosslinking temperature and a relatively high hole mobility, and is suitable for devices such as OLEDs and perovskite solar cells prepared by solution methods.

[0008] Another object of the present invention is to provide a preparation process for the above crosslinked polymer hole transport material.

[0009] Another object of the present invention is to provide the above polymer semiconductor material containing phenyl or pyridyl ethynyl triphenylamine and the crosslinked polymer hole transport material as hole transport layer materials in the fields of organic electroluminescent devices, organic solar cells, organic thin film transistors, and perovskite solar cells.

[0010] The object of the present invention is achieved by the following solutions:

[0011] A polymer semiconductor material containing phenyl or pyridyl ethynyl triphenylamine refers to a polymer semiconductor material containing phenyl ethynyl triphenylamine or a polymer semiconductor material containing pyridyl ethynyl triphenylamine, and has a structure shown in the following formula (I) or formula (II):

[0012]

[0013] In the said formula (I):

[0014] x and y are the molar fractions of each unit of the polymer monomer, where 0 < x ≤ 0.4, 0 < y ≤ 0.4, and x + y = 0.5; n is the degree of polymerization, and n is an integer from 10 to 300;

[0015] R1 is one of a straight-chain alkyl group with 1 to 5 carbon atoms or a branched-chain alkyl group with 1 to 5 carbon atoms;

[0016] R2 is relatively independently one of a straight-chain alkyl group with 6 to 16 carbon atoms or a branched-chain alkyl group with 4 to 30 carbon atoms;

[0017] Ar1 is one of the following structures, but is not limited to the following structural formulas;

[0018]

[0019] In the said formula (II):

[0020] x and y are the mole fractions of each unit of the polymer monomer, where 0 ≤ x ≤ 0.4, 0 < y ≤ 0.5, 0 < x + y ≤ 0.5; n is the repeating unit, and n is an integer from 10 to 300;

[0021] Ar1 is one of the structures shown below, but is not limited to the following structural formulas;

[0022]

[0023] Ar2 is one of the structures shown below, but is not limited to the following structural formulas;

[0024]

[0025] Preferably, the polymer semiconductor material containing phenyl or pyridyl ethynyl triphenylamine contains one of the following structures:

[0026]

[0027] A method for preparing the polymer semiconductor material containing phenyl or pyridyl ethynyl triphenylamine as described above, comprising the following steps:

[0028] (1) React N,N-bis(4-bromophenyl)-4-iodoaniline with Ar1-C≡H to obtain monomer compound M1;

[0029] The structural formula of the N,N-bis(4-bromophenyl)-4-iodoaniline is:

[0030]

[0031] (2) Place monomer compound M1, 4-bromo-N-(4-bromophenyl)-N-(4-alkylphenyl)aniline monomer a and 9,9-alkylfluorene-2,7-diboronic acid dipinacol ester monomer b in a solvent for palladium-catalyzed coupling reaction, and after the reaction is completed, obtain the polymer semiconductor formula (I);

[0032] The structural formula of the 4-bromo-N-(4-bromophenyl)-N-(4-alkylphenyl)aniline monomer a is:

[0033] [[ID=4​​​​​​​​​​

[0038] (3) Monomer compound M1, N,N-bis(4-bromophenyl)-2,4,6-trimethylaniline monomer c, Br-Ar2-Br and N,N-bis(4-boronic acid pinene ester phenyl)-2,4,6-trimethylaniline monomer d were placed in a solvent for palladium-catalyzed coupling reaction. After the reaction was completed, polymer semiconductor formula (II) was obtained.

[0039] The structural formula of monomer c, N,N-bis(4-bromophenyl)-2,4,6-trimethylaniline, is:

[0040]

[0041] The structural formula of N,N-bis(4-boronic acid pinene ester phenyl)-2,4,6-trimethylaniline monomer d is:

[0042]

[0043] Preferably, the preparation method of the polymer semiconductor material containing benzene or pyridine ethynyltriphenylamine specifically includes the following steps:

[0044] (1) N,N-bis(4-bromophenyl)-4-iodoaniline, Ar1-C≡H, cuprous iodide, palladium catalyst and solvent were mixed evenly, and then the mixture was refluxed and stirred for 1–10 hours. After cooling to room temperature, the reaction solution was purified to obtain monomer compound M1.

[0045] (2) M1, 4-bromo-N-(4-bromophenyl)-N-(4-alkylphenyl)aniline monomer a, 9,9-alkylfluorene-2,7-diboronic acid dipinarate monomer b, solvent and palladium catalyst were mixed evenly, and then the mixture was refluxed and stirred at 80-120°C for 10-72 hours. After cooling to room temperature, the reaction solution was purified to obtain the final product (I).

[0046] (3) M1, N,N-bis(4-bromophenyl)-2,4,6-trimethylaniline monomer c, Br-Ar2-Br, N,N-bis(4-boronic acid pinene ester phenyl)-2,4,6-trimethylaniline monomer d, solvent and palladium catalyst were mixed evenly, and then the mixture was refluxed and stirred at 80-120°C for 10-72 hours. After cooling to room temperature, the reaction solution was purified to obtain the final product (II).

[0047] The aforementioned polymer semiconductor materials containing benzene or pyridine ethynyltriphenylamine are used as hole transport materials in organic electroluminescent devices, organic solar cells, organic thin-film transistors, and perovskite solar cells.

[0048] The aforementioned polymer semiconductor material containing benzene or pyridine ethynyltriphenylamine can be cross-linked individually to form an amorphous thin film, and the cross-linked hole transport film can be obtained by heating in an inert gas or vacuum environment.

[0049] When preparing hole transport in organic electroluminescent devices, the polymer semiconductor material containing benzene or pyridine ethynyltriphenylamine is prepared by thermal initiation. The polymer semiconductor material containing benzene or pyridine ethynyltriphenylamine is spin-coated or spray-printed on a substrate and thermally initiated in an inert gas or vacuum environment to obtain a cross-linked hole transport film.

[0050] A cross-linked polymer hole transport material is characterized by being obtained by mixing the above-mentioned polymer semiconductor material containing benzene or pyridine ethynyl triphenylamine and a small molecule containing thiol and undergoing a cross-linking reaction through a "thiol-acetylene" click chemical reaction.

[0051] The structure of the small molecule containing a thiol group is shown in formula (III) below:

[0052]

[0053] When preparing hole transport for optoelectronic devices using this cross-linked polymer hole transport material, a small molecule cross-linked material containing thiol groups is blended with a polymer semiconductor material containing benzene or pyridine ethynyl triphenylamine. The resulting blend is dissolved in an organic solvent, and the cross-linked polymer hole transport material is spin-coated or spray-printed onto a substrate. After being irradiated with ultraviolet light and heated in an inert gas or vacuum environment, a "thiol-acetylene" click chemical reaction occurs, resulting in a cross-linked hole transport film.

[0054] A preparation process for the above-mentioned cross-linked polymer hole transport material includes the following steps:

[0055] (1) Solution preparation: Dissolve the polymer semiconductor material containing benzene or pyridine ethynyl triphenylamine in an organic solvent to prepare a solution, and then add a small molecule crosslinking agent containing thiol to form a mixed solution;

[0056] (2) Spin-coating hole transport layer: The prepared hole transport material and the mixture of small molecules containing thiol groups are coated on the substrate, then irradiated under ultraviolet light and then heated to obtain a fully cross-linked hole transport layer.

[0057] The organic solvent mentioned in step (1) is at least one of toluene, chlorobenzene, chloroform or xylene; the concentration of the solution prepared in step (1) is preferably 0.5-20 mg / mL.

[0058] The amount of the thiol-containing small molecule crosslinked material used in step (1) is 0.5-20 wt% of the mass of the polymer semiconductor material containing benzene or pyridine ethynyl triphenylamine.

[0059] The substrate mentioned in step (2) is preferably cleaned before use. The cleaning steps are as follows: wash the ultrasonic ITO substrate with water-anhydrous ethanol-acetone-isopropanol-anhydrous ethanol for 30 minutes in sequence, then boil the ethanol and dry the ITO substrate with nitrogen gas; bombard the cleaned ITO substrate with plasma in an oxygen plasma cleaner for 5 minutes.

[0060] The coating mentioned in step (2) refers to high-speed coating at a rotation speed of 500-4000 r / min for 5-50 s.

[0061] The irradiation under ultraviolet light mentioned in step (2) refers to irradiation with ultraviolet light of 250-380nm for 1-5 minutes under the protection of inert gas (such as nitrogen); the heating treatment refers to heating at 100-230℃ for 5-40 minutes under the protection of inert gas (such as nitrogen).

[0062] The above-mentioned cross-linked polymer hole transport materials are used in organic electroluminescent devices, organic solar cells, organic thin-film transistors, and perovskite solar cells.

[0063] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0064] 1. The synthesis method has the advantages of strong universality, short synthesis route, high synthesis yield and easy availability of reaction raw materials, and can be widely used in industrial scale-up synthesis and production;

[0065] 2. The main chain of this type of polymer has a large π-conjugated backbone, which can enhance the π-π interaction between molecular chains and improve carrier mobility.

[0066] 3. The cross-linked polymer hole transport material of the present invention can be mixed with cross-linked materials containing thiol groups to form an amorphous film through a "thiol-acetylene" click chemical reaction. This results in a material with a lower cross-linking temperature and better thermal stability.

[0067] 4. The series of benzene or pyridine ethynyltriphenylamine polymer hole transport materials disclosed in this invention have broad commercial prospects in the field of optoelectronic semiconductor materials such as organic light-emitting diodes, organic solar cells, organic field-effect transistors and perovskite solar cells. Attached Figure Description

[0068] Figure 1 The DSC curve of TFB-WC1, a polymer of benzene or pyridine ethynyl triphenylamine prepared in Example 1, is shown.

[0069] Figure 2 The DSC curve of PTAA-WC1, a benzene or pyridine ethynyl triphenylamine polymer prepared in Example 2, is shown.

[0070] Figure 3 The UV-Vis absorption spectra of the crosslinked film of the benzene or pyridine ethynyl triphenylamine polymer TFB-WC1 material prepared in Example 1 after heating at 200℃ for 30 min and then immersing it in chloroform for 5 min are shown.

[0071] Figure 4 The UV-Vis absorption spectra of the TFB-WC1 polymer material of benzene or pyridine ethynyltriphenylamine prepared in Example 1, after being crosslinked with a small molecule crosslinking agent containing thiol groups, after being irradiated with 365 nm UV light for 3 min and heated at 150 °C for 15 min, and then immersed in a solvent for 5 min.

[0072] Figure 5 The UV-Vis absorption spectra of the PTAA-WC1 polymer material of benzene or pyridine ethynyltriphenylamine prepared in Example 2, after being crosslinked with a small molecule crosslinking agent containing thiol groups, after being irradiated with 365 nm UV light for 3 min and heated at 150 °C for 15 min, and then immersed in a solvent for 5 min.

[0073] Figure 6 The voltage-current curves of the hole transport layer prepared in Example 1 are obtained by testing using the space charge-limited current method (SCLC).

[0074] Figure 7 The photoluminescence spectrum of the organic light-emitting diode prepared in Example 1 is shown. Detailed Implementation

[0075] The present invention will be further described in detail below with reference to embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto. Unless otherwise specified, the methods described are conventional methods. Unless otherwise specified, the raw materials are all commercially available. The reaction substrates N,N-bis(4-bromophenyl)aniline, N,N-bis(4-bromophenyl)-2,4,6-trimethylaniline, N,N-bis(4-boronic acid pinene ester phenyl)-2,4,6-trimethylaniline, N,N-bis(4-bromophenyl)-2,4,6-trimethylaniline, and N,N-bis(4-boronic acid pinene ester phenyl)-2,4,6-trimethylaniline used in the following embodiments are all commercially available, as are the reaction solvents and catalysts used.

[0076] Example 1

[0077] The synthetic route of a polymer semiconductor material with the chemical structure TFB-WC1 is shown below:

[0078]

[0079] (1) Synthesis of the intermediate with chemical structural formula a: N,N-bis(4-bromophenyl)aniline (2.02 g, 5.0 mmol), potassium iodide (0.83 g, 5.2 mmol), potassium iodate (1.6 g, 7.7 mmol), and acetic acid (15 mL) were sequentially added to a 50 mL double-necked round-bottom flask equipped with a condenser, a magnetic stirrer, and nitrogen inlet and outlet. The reaction mixture was stirred overnight at 80 °C under nitrogen. The mixture was then cooled to room temperature and poured into 200 mL of water. The precipitate was collected, dissolved in CH2Cl2, washed with aqueous Na2S2O3 solution, and dried over anhydrous MgSO4. After desolventizing by vacuum rotary evaporation, the product was collected and recrystallized with acetone to give a white solid (1.54 g, 61%).

[0080] The structural characterization data are as follows:

[0081] FT-IR (KBr, cm -1 ):3053,1573,1485,1312,1282,1270(CN),1173,1103,1071,1003,939,818,709,666. 1 H NMR(CDCl3,ppm)δ:7.58-7.52(d,2H),7.41-7.32(d,4H),6.99-6.89(d,4H),6.84-6.77(d,2H). 13 C NMR (CDCl3, ppm) δ: 146.80, 145.98, 138.48, 132.59, 125.84, 125.79, 116.23, 86.40 (CI).

[0082] As can be seen from the above, the structure of the compound is correct, and it is the compound shown, N,N-bis(4-bromophenyl)-4-iodoaniline.

[0083] (2) Synthesis of the monomer with chemical structure M1: Phenylacetylene (197 mg, 1.89 mmol) was added to a 50 mL double-necked round-bottom flask containing Pd(PPh3)2Cl2 (65.8 mg, 0.094 mmol), CuI (18.9 mg, 0.189 mmol), N,N-bis(4-bromophenyl)-4-iodoaniline (1.0 g, 1.89 mmol), triethylamine (NEt3) (5.5 mL), and anhydrous tetrahydrofuran (11 mL). The reaction mixture was stirred at room temperature for 24 h. The mixture was then filtered, and the solvent was removed under vacuum. The target product obtained by silica gel column chromatography was a white solid (0.70 g, 74%).

[0084] The structural characterization data are as follows:

[0085] FT-IR (KBr, cm -1 ):3059(ar.CH),3033,2215(C≡C),1581,1507,1483(ar.C=C),1314,1286,1267(CN),1070,1008,822,755,689. 1 H NMR(CDCl3,ppm)d:7.52-7.49(m,2H),7.42-7.26(m,9H),7.01-6.94(dd,6H). 13 C NMR(CDCl3,ppm)d:146.89,145.98,132.84,132.60,131.55,128.39,128. 17,126.13,123.40,123.11,117.55,116.37,89.24('C≡C),89.22(C≡C').

[0086] As can be seen from the above, the structure of the compound is correct, and it is the compound shown, N,N-bis(4-bromophenyl)-4-(2-phenylethynyl)aniline.

[0087] (3) Synthesis of polymer TFB-WC1 with chemical structure shown in formula (I): Under the protection of argon atmosphere, monomers 4-bromo-N-(4-bromophenyl)-N-(4-sec-butylphenyl)aniline (82.66 mg, 0.18 mmol), 9,9-di-n-octylfluorene-2,7-diboronic acid dipinarate (192.77 mg, 0.30 mmol), N,N-bis(4-bromophenyl)-4-(2-phenylethynyl)aniline (60.12 mg, 0.12 mol), tetra-triphenylphosphine palladium (2 mg), tricyclohexylphosphine (4 mg), tetraethylammonium hydroxide (1.5 mL) and purified toluene (8 mL) were added to a 50 mL two-necked flask, heated to 80 °C and reacted for 24 hours, and then capped with phenylboronic acid (25 mg) and bromobenzene (0.5 mL) for 6 hours in succession. After the reaction was completed, the mixture was allowed to cool naturally and stand. Then, it was precipitated into 200 mL of methanol. The filtered solid was dried and purified by Soxhlet extraction with methanol, acetone, and chloroform. The chloroform fraction was concentrated and dissolved in an appropriate amount of toluene. It was then purified by a double-layer column of silica gel and alumina with a 200-300 mesh as the eluent. The toluene solution was concentrated and added dropwise to 200 mL of methanol solution again for precipitation. The solution was filtered and dried in a vacuum oven to obtain a yellow flocculent solid with a yield of 90%.

[0088] The molecular weight characterization data of the obtained polymer are as follows: weight average molecular weight is 111.9 kDa, number average molecular weight is 24.7 kDa, and polymer molecular weight distribution index is 4.54.

[0089] Example 2

[0090] The synthetic route of a polymer semiconductor material with the chemical structure PTAA-WC1 is shown below:

[0091]

[0092] (1) Synthesis of the intermediate with chemical structural formula a: synthesized according to the synthesis method of Example 1 above.

[0093] (2) Synthesis of monomer with chemical structure M1: synthesized according to the synthesis method of Example 1 above.

[0094] (3) Under the protection of argon atmosphere, monomers N,N-bis(4-bromophenyl)-2,4,6-trimethylaniline (79.74 mg, 0.18 mmol), N,N-bis(4-boronic acid pinene ester phenyl)-2,4,6-trimethylaniline (164.40 mg, 0.30 mmol), N,N-bis(4-bromophenyl)-4-(2-phenylethynyl)aniline (60.12 mg, 0.12 mol), tetratriphenylphosphine palladium (2 mg), tricyclohexylphosphine (4 mg), tetraethylammonium hydroxide (1.5 mL) and purified toluene (8 mL) were added to a 50 mL two-necked flask, heated to 80 °C and reacted for 24 hours. Then, the flask was sealed with phenylboronic acid (25 mg) and bromobenzene (0.5 mL) for 6 hours. After the reaction was completed, the mixture was allowed to cool naturally and stand. Then, the solid was precipitated into 200 mL of methanol. The filtered solid was dried and purified by Soxhlet extraction with methanol, acetone, and chloroform. The chloroform fraction was concentrated and dissolved in an appropriate amount of toluene. The solid was purified by a double-layer column of silica gel and alumina with a 200-300 mesh as the eluent. The toluene solution was concentrated and added dropwise to 200 mL of methanol solution for precipitation. The solution was filtered and dried in a vacuum oven to obtain a yellow powdery solid with a yield of 90%.

[0095] The molecular weight characterization data of the obtained polymer are as follows: weight average molecular weight is 68.1 kDa, number average molecular weight is 16.7 kDa, and polymer molecular weight distribution index is 4.07.

[0096] Example 3

[0097] The synthetic route of a polymer semiconductor material with the chemical structure PTAA-WC2 is shown below:

[0098]

[0099] (1) Synthesis of the intermediate with chemical structural formula a: synthesized according to the synthesis method of Example 1 above.

[0100] (2) Synthesis of monomer with chemical structure M1: synthesized according to the synthesis method of Example 1 above.

[0101] (3) Under the protection of argon atmosphere, monomers 3,5-dibromopyridine (4.70 mg, 0.02 mmol), N,N-bis(4-bromophenyl)-2,4,6-trimethylaniline monomer (70.88 mg, 0.16 mmol), N,N-bis(4-boronic acid pinene ester phenyl)-2,4,6-trimethylaniline (164.40 mg, 0.30 mmol), N,N-bis(4-bromophenyl)-4-(2-phenylethynyl)aniline (60.12 mg, 0.12 mol), tetratriphenylphosphine palladium (2 mg), tricyclohexylphosphine (4 mg), tetraethylammonium hydroxide (1.5 mL) and purified toluene (8 mL) were added to a 50 mL two-necked flask, heated to 80 °C and reacted for 24 hours, and then the flask was sealed with phenylboronic acid (25 mg) and bromobenzene (0.5 mL) for 6 hours in sequence. After the reaction was completed, the mixture was allowed to cool naturally and stand. Then, the solid was precipitated into 200 mL of methanol. The filtered solid was dried and purified by Soxhlet extraction with methanol, acetone, and chloroform. The chloroform fraction was concentrated and dissolved in an appropriate amount of toluene. The solid was purified by a double-layer column of silica gel and alumina with a mesh size of 200-300 mesh. The eluent was toluene. The toluene solution was concentrated and added dropwise to 200 mL of methanol solution for precipitation. The solution was filtered and dried in a vacuum oven to obtain a yellow powder solid with a yield of 90%.

[0102] The molecular weight characterization data of the obtained polymer are as follows: weight average molecular weight is 79.0 kDa, number average molecular weight is 17.0 kDa, and polymer molecular weight distribution index is 4.65.

[0103] Example 4

[0104] The synthetic route of a polymer semiconductor material with the chemical structure PTAA-WC3 is shown below:

[0105]

[0106] (1) Synthesis of the intermediate with chemical structural formula a: synthesized according to the synthesis method of Example 1 above.

[0107] (2) Synthesis of the monomer with chemical structure M2: Pyridineacetylene (195 mg, 1.89 mmol) was added to a 50 mL double-necked round-bottom flask containing Pd(PPh3)2Cl2 (65.8 mg, 0.094 mmol), CuI (18.9 mg, 0.189 mmol), N,N-bis(4-bromophenyl)-4-iodoaniline (1.0 g, 1.89 mmol), triethylamine (NEt3) (5.5 mL), and anhydrous tetrahydrofuran (11 mL). The reaction mixture was stirred at room temperature for 24 h. The mixture was then filtered, and the solvent was removed under vacuum. The target product obtained by silica gel column chromatography was a white solid (0.79 g, 83%).

[0108] The structural characterization data are as follows:

[0109] FT-IR (KBr, cm -1 ):3032,2240(C=N),2212(C≡C),1647,1599,1575,1504,

[0110] 1479(ar.C=C),1404,1314,1284,1265(CN),1179,1142,1001,818,803,700. 1 HNMR(CDCl3,ppm)d:8.77-8.73(s,1H),8.58-5.50(d,1H),7.52-7.49(m,2H),7.42-7.26(m,9H),7.01-6.94(dd,6H). 13 C NMR(CDCl3,ppm)d:150.06(C=N),148.15,146.68,132.57,132.16,129.7 0,129.52,124.72,120.88,118.46,112.59,89.24('C≡C),89.22(C≡C').

[0111] As can be seen from the above, the structure of the compound is correct, and it is the compound shown, N,N-bis(4-bromophenyl)-4-(2-pyridylethynyl)aniline.

[0112] (3) Under the protection of argon atmosphere, monomers N,N-bis(4-bromophenyl)-2,4,6-trimethylaniline (73.78 mg, 0.18 mmol), N,N-bis(4-boronic acid pinene ester phenyl)-2,4,6-trimethylaniline (164.40 mg, 0.30 mmol), N,N-bis(4-bromophenyl)-4-(2-pyridylethynyl)aniline (60.12 mg, 0.12 mol), tetratriphenylphosphine palladium (2 mg), tricyclohexylphosphine (4 mg), tetraethylammonium hydroxide (1.5 mL) and purified toluene (8 mL) were added to a 50 mL two-necked flask, heated to 80 °C and reacted for 24 hours. Then, the flask was sealed with phenylboronic acid (25 mg) and bromobenzene (0.5 mL) for 6 hours. After the reaction was completed, the mixture was allowed to cool naturally and stand. Then, the solid was precipitated into 200 mL of methanol. The filtered solid was dried and purified by Soxhlet extraction with methanol, acetone, and chloroform. The chloroform fraction was concentrated and dissolved in an appropriate amount of toluene. The solid was purified by a double-layer column of silica gel and alumina with a 200-300 mesh as the eluent. The toluene solution was concentrated and added dropwise to 200 mL of methanol solution for precipitation. The solution was filtered and dried in a vacuum oven to obtain a yellow powdery solid with a yield of 90%.

[0113] The molecular weight characterization data of the obtained polymer are as follows: weight-average molecular weight is 75.1 kDa, number-average molecular weight is 18.7 kDa, and polymer molecular weight distribution index is 4.02.

[0114] Example 5

[0115] Crosslinked hole transport layer fabrication process

[0116] (1) Solution preparation: Dissolve the polymer semiconductor material in toluene to prepare a solution with a concentration of 10 mg / mL and add 5 wt% of a crosslinking agent containing thiol small molecules to the polymer semiconductor material.

[0117] (2) Cleaning the substrate: The ultrasonically cleaned ITO substrate was washed sequentially with deionized water, anhydrous ethanol, acetone, isopropanol, and anhydrous ethanol for 30 minutes. Then, the ethanol was boiled and the ITO substrate was dried with nitrogen. The cleaned ITO substrate was bombarded with plasma in an oxygen plasma cleaner for 5 minutes to remove residual organic contaminants, improve the interface contact angle, and increase the work function.

[0118] (3) Take 20 μL of the prepared polymer semiconductor and mercapto-containing small molecule mixture solution and coat it at a high speed of 2000 r / min for 30 s. Then, irradiate it with 365 nm ultraviolet light in a glove box under nitrogen atmosphere for 3 min and heat it at 150 °C for 10 min under nitrogen atmosphere to obtain a fully cross-linked hole transport layer.

[0119] The UV-Vis absorption spectra of the fully cross-linked hole transport layer film prepared in this example using the benzene or pyridine ethynyltriphenylamine-based polymer TFB-WC1 material and a thiol-containing small molecule cross-linking agent, after immersion in a solvent for 5 minutes, are shown below. Figure 4 As shown, the UV-Vis absorption spectra of the fully cross-linked hole transport layer film prepared in this example using the benzene or pyridine ethynyltriphenylamine polymer PTAA-WC1 material prepared in Example 2 and the thiol-containing small molecule cross-linking agent are shown before and after immersion in a solvent for 5 minutes. Figure 5 As shown, from Figure 4 and Figure 5 As can be seen from this, the fully cross-linked hole transport layer film of the present invention does indeed solve the problem of interlayer co-solution.

[0120] The hole transport layer prepared from the polymer semiconductor material in Example 1 using the fabrication process described in this example was subjected to performance testing. The hole carrier mobility was tested using the space charge confined current method (SCLC), and the voltage-current curves are shown below. Figure 6 As shown. From Figure 6 It can be seen that cross-linking can reduce the hole mobility of TFB-WC1 from 3.23 × 10⁻⁶. -4 Increased to 4.78×10 -3 cm 2 V -1 s -1 .

[0121] Application Example 1

[0122] The hole transport layer prepared in Example 1 was applied to an organic light-emitting diode (OLED). The specific steps are as follows:

[0123] (1) Spin-coating hole injection layer PEDOT: PSS is applied to the anode ITO and then annealed at 140℃ for 20 min to obtain a hole injection layer with a thickness of 30 nm.

[0124] (2) The polymer semiconductor material with chemical structure TFB-WC1 in Example 1 was dissolved in toluene to prepare a solution with a concentration of 10 mg / mL and a crosslinking agent containing thiol small molecules PETMP was added as 5 wt% of the polymer molecules; it was spin-coated onto PEDOT:PSS and then annealed at 140 °C for 10 min under 365 nm ultraviolet light to obtain a hole transport layer with a thickness of 25 nm.

[0125] (3) Spin-coat the polymer luminescent material PFSO (60nm) onto the hole transport layer obtained in step (2) in a glove box, and then anneal at 100°C for 5 minutes to obtain a luminescent film;

[0126] (4) At a vacuum degree of 6×10 -4Under the condition of Pa, an electron transport layer CsF (thickness of 1 nm) is vapor-deposited on the luminescent material in step (3);

[0127] (5) At a vacuum degree of 6×10 -4 Under the condition of Pa, a cathode layer Al (thickness of 100 nm) is vapor-deposited into the electron transport layer of step (4) to obtain a quantum dot light-emitting diode.

[0128] In contrast, the polymer semiconductor material with the chemical structure TFB-WC1 in Example 1 of step (2) is replaced with polymer TFB.

[0129] Table 1. Photoelectric performance indicators of electroluminescent devices with cross-linked materials formed by polymer TFB and thiol-containing small molecules as hole transport layers, and TFB-WCl and cross-linked materials formed by thiol-containing small molecules as hole transport layers.

[0130]

[0131] As shown in Table 1, compared with the photoelectric performance of electroluminescent devices prepared by using cross-linked materials formed by TFB and thiol-containing small molecules as hole transport layers, the maximum efficiency and maximum brightness of TFB-WC1 and cross-linked materials formed by thiol-containing small molecules are significantly improved, while the turn-on voltage is not significantly different.

[0132] Figure 7 The photoluminescence spectrum of the organic light-emitting diode prepared in Example 1 is shown. Figure 7 It can be seen that the EL wavelength shift of the organic light-emitting diode is 454nm and the full width at half maximum (FWHM) is 40nm, indicating that the polymer described in this example does not affect the luminescence performance and can enable the luminescent polymer to emit light effectively.

[0133] The above embodiments are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A polymer semiconductor material containing benzene or pyridine-ethynyltriphenylamine, characterized in that... It has the structure shown in the following formula (I) or formula (II): In the said formula (I): x, y, and z are the molar fractions of each unit of the polymer monomer, where 0 < x ≤ 0.4, 0 < y ≤ 0.4, x + y = 0.5, and x + y + z = 1; n is the degree of polymerization, and n is an integer from 10 to 300; R1 is one of a straight-chain alkyl group with 1 - 5 carbon atoms or a branched-chain alkyl group with 1 - 5 carbon atoms; R2 is independently one of a straight-chain alkyl group with 6 - 16 carbon atoms or a branched-chain alkyl group with 4 - 30 carbon atoms; Ar1 is one of the following structures; In the said formula (II): x, y, and z are the molar fractions of each unit of the polymer monomer, where 0 ≤ x ≤ 0.4, 0 < y ≤ ​ ​ 2. The polymer semiconductor material containing benzene or pyridine ethynyltriphenylamine according to claim 1, characterized in that... ​ 3. A method for preparing a polymer semiconductor material containing benzene or pyridine ethynyltriphenylamine according to claim 1 or 2, characterized in that... ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 4. The method for preparing polymer semiconductor materials containing benzene or pyridine-acetylene-based triphenylamines according to claim 3, characterized in that... ​ ​ (2) M1, 4-bromo-N-(4-bromophenyl)-N-(4-alkylphenyl)aniline monomer a, 9,9-alkylfluorene-2,7-diboronic acid dipinarate monomer b, solvent and palladium catalyst were mixed evenly, and then the mixture was refluxed and stirred at 80-120°C for 10-72 hours. After cooling to room temperature, the reaction solution was purified to obtain the final product (I). (3) M1, N,N-bis(4-bromophenyl)-2,4,6-trimethylaniline monomer c, Br-Ar2-Br, N,N-bis(4-boronic acid pinene ester phenyl)-2,4,6-trimethylaniline monomer d, solvent and palladium catalyst were mixed evenly, and then the mixture was refluxed and stirred at 80-120°C for 10-72 hours. After cooling to room temperature, the reaction solution was purified to obtain the final product (II).

5. A cross-linked polymer hole transport material, characterized in that... The mixture of a polymer semiconductor material containing benzene or pyridine ethynyl triphenylamine as described in claim 1 or 2 and a small molecule containing thiol groups undergoes a cross-linking reaction via a "thiol-alkynyl" click chemistry reaction. The structure of the small molecule containing a thiol group is shown in formula (III) below:

6. A preparation process for a cross-linked polymer hole transport material according to claim 5, characterized in that... Includes the following steps: (1) Solution preparation: Dissolve the polymer semiconductor material containing benzene or pyridine ethynyl triphenylamine in an organic solvent to prepare a solution, and then add a small molecule crosslinking agent containing thiol to form a mixed solution; (2) Spin-coating hole transport layer: The prepared hole transport material and the mixture of small molecules containing thiol groups are coated on the substrate, then irradiated under ultraviolet light and then heated to obtain a fully cross-linked hole transport layer.

7. The preparation process of the cross-linked polymer hole transport material according to claim 6, characterized in that: The organic solvent mentioned in step (1) is at least one of toluene, chlorobenzene, chloroform or xylene; the concentration of the polymer semiconductor material containing benzene or pyridine ethynyl triphenylamine dissolved in the organic solvent in step (1) is 0.5-20 mg / mL. The amount of the thiol-containing small molecule crosslinked material used in step (1) is 0.5-20 wt% of the mass of the polymer semiconductor material containing benzene or pyridine ethynyl triphenylamine.

8. The preparation process of the cross-linked polymer hole transport material according to claim 6, characterized in that: The substrate described in step (2) is first cleaned before use. The cleaning steps are as follows: the ultrasonic ITO substrate is washed sequentially with water-anhydrous ethanol-acetone-isopropanol-anhydrous ethanol for 30 minutes, then the ethanol is boiled and the ITO substrate is dried with nitrogen gas; the cleaned ITO substrate is bombarded with plasma in an oxygen plasma cleaner for 5 minutes.

9. The preparation process of the cross-linked polymer hole transport material according to claim 6, characterized in that: The coating mentioned in step (2) refers to high-speed coating at a rotation speed of 500-4000 r / min for 5-50 s; The irradiation under ultraviolet light mentioned in step (2) refers to irradiation with ultraviolet light of 250-380nm for 1-5 minutes under inert gas protection; the heating treatment refers to heating at 100-230℃ for 5-40 minutes under inert gas protection.

10. The application of the polymer semiconductor material containing benzene or pyridine ethynyltriphenylamine as described in claim 1 or 2 and the cross-linked polymer hole transport material as described in claim 5 in the fields of organic electroluminescent devices, organic solar cells, organic thin-film transistors and perovskite solar cells.

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