A method for preparing grafted thiophene polymer materials

Abstract

This invention discloses a method for preparing a grafted thiophene polymer material, comprising the following steps: mixing poly(3-hexylthiophene), a grafting monomer, a catalyst, and an auxiliary agent, and heating the mixture to obtain the grafted thiophene polymer material; the structural formula of the grafting monomer is shown in formula (I); wherein, B is fluorine, chlorine, bromine, or iodine, A is a carbon atom or a nitrogen atom, and R is a cyano, formyl, methoxycarbonyl, or cyano; this invention avoids the pre-synthesis of complex functional monomers, eliminates the need for expensive catalysts or ligands, and can directly modify the poly(3-hexylthiophene) backbone without interfering with the polymerization reaction of poly(3-hexylthiophene) itself, while also possessing the advantages of simplified steps and low cost.

Description

Technical Field

[0001] This invention belongs to the technical field of grafted thiophene polymer synthesis methods, and particularly relates to a method for preparing grafted substituted thiophene polymer materials. Background Technology

[0002] In recent years, to address the increasingly severe energy and environmental problems, people have turned their attention to the development and utilization of new energy sources. Among various new energy technologies, solar power generation is undoubtedly one of the most promising directions. Among the many new types of solar cells, perovskite solar cells have stood out in the past two years due to their advantages such as low raw material prices, simple production processes, ability to be fabricated on flexible substrates, and the ability to be fabricated on a large area using methods such as coating and printing.

[0003] Perovskite solar cells mainly consist of a substrate layer, a hole transport layer, a wetting layer, a perovskite active layer, an electron transport layer, a hole blocking layer, and an electrode layer. Among these, the hole transport layer is a crucial component of perovskite solar cells, playing a key role in carrier extraction and transport, as well as suppressing carrier recombination. Thiophene polymers are an important material for preparing hole transport layers; however, existing thiophene polymers suffer from disadvantages such as the need for pre-synthesizing complex functional monomers, lengthy monomer preparation steps, and the use of expensive catalysts or ligands. Summary of the Invention

[0004] To address the shortcomings of the prior art, this invention provides a method for preparing grafted thiophene polymer materials. This method successfully grafts functional monomers onto the β-H sites of poly-3-hexylthiophene, obtaining grafted thiophene polymers with different grafting rates. This invention avoids the pre-synthesis of complex functional monomers, eliminates the need for expensive catalysts or ligands, and can directly modify the poly-3-hexylthiophene backbone without interfering with the polymerization reaction of poly-3-hexylthiophene itself. It also has the advantages of simplified steps and low cost.

[0005] The purpose of this invention is to provide a method for preparing grafted thiophene polymer materials, comprising the following steps:

[0006] Poly(3-hexylthiophene), grafted monomers, catalysts and auxiliaries are mixed and heated to react, yielding grafted substituted thiophene polymer materials.

[0007] The structural formula of the grafted monomer is shown in formula (Ⅰ):

[0008] ;

[0009] Equation (Ⅰ);

[0010] Where B is fluorine, chlorine, bromine, or iodine, A is a carbon atom or a nitrogen atom, and R is a cyano group, formyl group, methoxycarbonyl group, or... .

[0011] In some embodiments of the present invention, B is bromine.

[0012] In some embodiments of the present invention, the molar ratio of the poly(3-hexylthiophene), the grafted monomer and the catalyst is 1:0.05~1.8:0.005~0.035.

[0013] In some embodiments of the present invention, the catalyst comprises palladium chloride.

[0014] In some embodiments of the present invention, the adjuvants include organophosphorus ligands, inorganic bases, organic acids, and solvents.

[0015] In some embodiments of the present invention, the organophosphorus ligand is selected from triphenylphosphine.

[0016] In some embodiments of the present invention, the inorganic base is selected from potassium carbonate.

[0017] In some embodiments of the present invention, the organic acid is selected from pivalic acid.

[0018] In some embodiments of the present invention, the solvent is selected from toluene.

[0019] In some embodiments of the present invention, the molar ratio of the poly(3-hexylthiophene) to the organophosphorus ligand is 1:0.001~0.06.

[0020] In some embodiments of the present invention, the molar ratio of the poly(3-hexylthiophene) to the inorganic base is 1:0.1~2.0.

[0021] In some embodiments of the present invention, the molar ratio of the poly(3-hexylthiophene) to the organic acid is 1:0.01~0.3.

[0022] In some embodiments of the present invention, the heating reaction is carried out at a temperature of 80-120°C for 18-30 hours.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] (1) The method of the present invention successfully grafted functional monomers onto the β-H site of poly(3-hexylthiophene) to obtain grafted thiophene polymers with different grafting rates.

[0025] (2) This invention avoids the pre-synthesis of complex functional monomers, and can directly modify the poly(3-hexylthiophene) backbone without the use of expensive catalysts or ligands, without interfering with the polymerization reaction of poly(3-hexylthiophene) itself. It also has the advantages of simplified steps and low cost. Attached Figure Description

[0026] The accompanying drawings are provided to further illustrate the present application and form part of the specification. Together with the embodiments of the present application, they serve to explain the present application but do not constitute a limitation thereof. In the drawings:

[0027] Figure 1 The 1H NMR spectrum of the 2-cyanopyridine-grafted thiophene polymer material prepared in Example 1 is shown.

[0028] Figure 2 The 1H NMR spectrum of the 2-pyridinecarboxaldehyde-grafted thiophene polymer material prepared in Example 2 is shown.

[0029] Figure 3 The 1H NMR spectrum of the 2-pyridinecarboxylate-grafted thiophene polymer material prepared in Example 3 is shown.

[0030] Figure 4 The 1H NMR spectrum of the functionalized phenyl-grafted thiophene polymer material prepared in Example 4.

[0031] Figure 5 The 1H NMR spectrum of the functionalized phenyl-grafted thiophene polymer material prepared in Example 5.

[0032] Figure 6 The 1H NMR spectrum of the thiophene polymer material grafted with diethyl benzyl phosphite prepared in Example 6 is shown. Detailed Implementation

[0033] To enable those skilled in the art to better understand the technical solutions of this invention, the technical solutions of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this invention.

[0034] All raw materials used in this invention are commercially available.

[0035] The structure of commercially available poly-3-hexylthiophene used in all embodiments and comparative examples of this invention is as follows:

[0036] The structure of poly-3-hexylthiophene is as follows:

[0037] ;

[0038] Poly(3-hexylthiophene a) represents poly(3-hexylthiophene) with a number-average molecular weight of 10.1 kDa, a molecular weight distribution index of 2.3, and an isotacticity of 92%.

[0039] Poly(3-hexylthiophene b) represents poly(3-hexylthiophene) with a number-average molecular weight of 16.3 kDa, a molecular weight distribution index of 2.4, and an isotacticity of 92%.

[0040] Poly(3-hexylthiophene)c represents poly(3-hexylthiophene) with a number-average molecular weight of 15.7 kDa, a molecular weight distribution index of 2.9, and an isotacticity of 94%.

[0041] Example 1

[0042] This embodiment provides a 2-cyanopyridine-grafted thiophene polymer material, the preparation method of which includes the following steps:

[0043] Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene a) (1.0 mmol), 2-cyano-5-bromopyridine (0.1 mmol), potassium carbonate (0.2 mmol), palladium chloride (0.001 mmol), triphenylphosphine (0.002 mmol), tervaponic acid (0.03 mmol), and toluene (10 mL) were reacted at 100 °C for 24 h. After the reaction, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and then washed repeatedly with ultrapure water and n-hexane. After drying, a 2-cyanopyridine-grafted thiophene polymer material was obtained with a yield of 78%, a number-average molecular weight (Mn) of 11.3 kDa, a molecular weight distribution index (PDI) of 2.3, and a 2-cyanopyridine-grafted segment comprising 1.6% of the 2-cyanopyridine-grafted thiophene polymer material, i.e., a grafting rate of 1.6%. mol% , wherein the 2-cyanopyridine-grafted thiophene polymer material comprises a 2-cyanopyridine-grafted thiophene polymer and poly-3-hexylthiophene without unparticipated grafting reaction, and the structure of the 2-cyanopyridine-grafted thiophene polymer is shown below:

[0044] .

[0045] Example 2

[0046] This embodiment provides a 2-pyridinecarboxaldehyde-grafted thiophene polymer material, the preparation method of which includes the following steps:

[0047] Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene a) (1.0 mmol), 5-bromo-2-pyridinecarboxaldehyde (0.1 mmol), potassium carbonate (0.2 mmol), palladium chloride (0.001 mmol), triphenylphosphine (0.002 mmol), tervamolic acid (0.03 mmol), and toluene (10 mL) were reacted at 100 °C for 24 h. After the reaction, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and then washed repeatedly with ultrapure water and n-hexane. The polymer was then dried to obtain a 2-pyridinecarboxaldehyde-grafted thiophene polymer material with a yield of 82%, a number-average molecular weight (Mn) of 12.0 kDa, a molecular weight distribution index (PDI) of 2.3, and a 2-pyridinecarboxaldehyde-grafted segment comprising 1.1% of the 2-pyridinecarboxaldehyde-grafted thiophene polymer material, i.e., a grafting rate of 1.1%. mol% , wherein the 2-pyridinecarboxaldehyde-grafted thiophene polymer material comprises a 2-pyridinecarboxaldehyde-grafted thiophene polymer and poly-3-hexylthiophene that has not participated in the grafting reaction, and the structure of the 2-pyridinecarboxaldehyde-grafted thiophene polymer is shown below:

[0048] .

[0049] Example 3

[0050] This embodiment provides a thiophene polymer material grafted with methyl 2-pyridinecarboxylate, the preparation method of which includes the following steps:

[0051] Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene a) (1.0 mmol), methyl 5-bromopyridine-2-carboxylate (0.1 mmol), potassium carbonate (0.2 mmol), palladium chloride (0.001 mmol), triphenylphosphine (0.002 mmol), terpentine (0.03 mmol), and toluene (10 mL) were reacted at 100 °C for 24 h. After the reaction, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and then washed repeatedly with ultrapure water and n-hexane. The polymer was then dried to obtain a 2-pyridinecarboxylate-grafted thiophene polymer material with a yield of 73% and a number-average molecular weight (Mn) of 11.2. The molecular weight distribution index (PDI) is 2.2, and the methyl 2-pyridinecarboxylate segment accounts for 1.0% of the 2-pyridinecarboxylate-grafted thiophene polymer material, i.e., the grafting rate is 1.0 mol%. The 2-pyridinecarboxylate-grafted thiophene polymer material comprises a 2-pyridinecarboxylate-grafted thiophene polymer and no unreacted poly-3-hexylthiophene. The structure of the 2-pyridinecarboxylate-grafted thiophene polymer is shown below:

[0052] .

[0053] Example 4

[0054] This embodiment provides a functionalized phenyl-grafted thiophene polymer material, the preparation method of which includes the following steps:

[0055] Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene b) (1.0 mmol), 4-bromobenzonitrile (0.1 mmol), potassium carbonate (0.2 mmol), palladium chloride (0.001 mmol), triphenylphosphine (0.002 mmol), tervaponic acid (0.03 mmol), and toluene (10 mL) were reacted at 100 °C for 24 h. After the reaction, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and then washed repeatedly with ultrapure water and n-hexane. The polymer was then dried to obtain a functionalized phenyl-grafted thiophene polymer material with a yield of 80%, a number-average molecular weight (Mn) of 17.7 kDa, a PDI of 2.6, and a benzonitrile graft segment comprising 1.4% of the functionalized phenyl-grafted thiophene polymer material, i.e., a grafting rate of 1.4%. mol% , wherein the functionalized phenyl-grafted thiophene polymer material comprises a benzonitrile-grafted thiophene polymer and poly-3-hexylthiophene without unparticipated grafting reaction, and the structure of the benzonitrile-grafted thiophene polymer is shown below:

[0056] .

[0057] Example 5

[0058] This embodiment provides a functionalized phenyl-grafted thiophene polymer material, the preparation method of which includes the following steps:

[0059] Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene b) (1.0 mmol), 4-bromobenzaldehyde (0.1 mmol), potassium carbonate (0.2 mmol), palladium chloride (0.001 mmol), triphenylphosphine (0.002 mmol), tervamolic acid (0.03 mmol), and toluene (10 mL) were reacted at 100 °C for 24 h. After the reaction, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and then washed repeatedly with ultrapure water and n-hexane. After drying, a functionalized phenyl-grafted thiophene polymer material was obtained with a yield of 88%, a number-average molecular weight (Mn) of 18.1 kDa, a PDI of 2.6, and a benzaldehyde graft segment comprising 1.7% of the functionalized phenyl-grafted thiophene polymer material, i.e., a grafting rate of 1.7%. mol% , wherein the functionalized phenyl-grafted thiophene polymer material comprises benzaldehyde-grafted thiophene polymer and poly-3-hexylthiophene without unparticipated grafting reaction, and the structure of the benzaldehyde-grafted thiophene polymer is shown below:

[0060] .

[0061] Example 6

[0062] This embodiment provides a thiophene polymer material grafted with diethyl benzyl phosphite, the preparation method of which includes the following steps:

[0063] Under a nitrogen atmosphere, commercially available poly(3-hexylthiophene C) (1.0 mmol), diethyl 4-bromobenzyl phosphite (1.5 mmol), potassium carbonate (2.0 mmol), palladium chloride (0.03 mmol), triphenylphosphine (0.06 mmol), tervamol acid (0.3 mmol), and toluene (10 mL) were reacted at 80 °C for 48 h. After the reaction, the mixture was cooled to room temperature, the polymer was precipitated with methanol, and then washed repeatedly with ultrapure water and n-hexane. The polymer was then dried to obtain a benzyl phosphite-grafted thiophene polymer material with a yield of 75%, a number-average molecular weight (Mn) of 17.0 kDa, a PDI of 3.1, and a benzyl phosphite graft segment comprising 5.8% of the total molar percentage of the benzyl phosphite-grafted thiophene polymer material, i.e., a grafting rate of 5.8%. mol% , wherein the benzyl diethyl phosphite-grafted thiophene polymer material comprises a benzyl diethyl phosphite-grafted thiophene polymer and poly-3-hexylthiophene that has not participated in the grafting reaction, and the structure of the benzyl diethyl phosphite-grafted thiophene polymer is shown below:

[0064] .

[0065] As can be seen from Examples 1-6, the method for preparing grafted thiophene polymer materials of the present invention successfully grafts different groups onto the β-H sites of poly-3-hexylthiophene, obtaining grafted thiophene polymers with different grafting rates; it avoids the pre-synthesis of complex functional monomers, does not require the use of expensive catalysts or ligands, and can directly modify the poly-3-hexylthiophene backbone without interfering with the polymerization reaction of poly-3-hexylthiophene itself, while having the advantages of simplified steps and low cost.

[0066] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that after reading this application specification, they can still modify or make equivalent substitutions to the specific implementation of the present invention, but these modifications or changes do not depart from the protection scope of the pending claims of the present invention.

Claims

1. A method for preparing a grafted thiophene polymer material, characterized in that, Includes the following steps: Poly(3-hexylthiophene), grafted monomers, catalysts and auxiliaries are mixed and heated to react, yielding grafted substituted thiophene polymer materials. The structural formula of the grafted monomer is shown in formula (Ⅰ): ； Equation (Ⅰ); Where B is fluorine, chlorine, bromine, or iodine, A is a carbon atom or a nitrogen atom, and R is a cyano group, formyl group, methoxycarbonyl group, or... .

2. The method for preparing the grafted thiophene polymer material according to claim 1, characterized in that, B is bromine.

3. The method for preparing the grafted thiophene polymer material according to claim 1, characterized in that, The molar ratio of poly(3-hexylthiophene), grafted monomer and catalyst is 1:0.05~1.8:0.005~0.

035.

4. The method for preparing the grafted thiophene polymer material according to claim 1, characterized in that, The catalyst includes palladium chloride.

5. The method for preparing the grafted thiophene polymer material according to claim 1, characterized in that, The additives include organophosphorus ligands, inorganic bases, organic acids, and solvents.

6. The method for preparing the grafted thiophene polymer material according to claim 5, characterized in that, The organophosphorus ligand is selected from triphenylphosphine; And / or, the inorganic base is selected from potassium carbonate; And / or, the organic acid is selected from pivalic acid; And / or, the solvent is selected from toluene.

7. The method for preparing the grafted thiophene polymer material according to claim 5, characterized in that, The molar ratio of poly(3-hexylthiophene) to organophosphorus ligands is 1:0.001~0.

06.

8. The method for preparing the grafted thiophene polymer material according to claim 5, characterized in that, The molar ratio of poly(3-hexylthiophene) to inorganic base is 1:0.1~2.

0.

9. The method for preparing the grafted thiophene polymer material according to claim 5, characterized in that, The molar ratio of poly(3-hexylthiophene) to organic acid is 1:0.01~0.

3.

10. The method for preparing the grafted thiophene polymer material according to claim 1, characterized in that, The heating reaction is carried out at a temperature of 80~120℃ for 18~30 hours.

Images