A method for preparing a thienopyrrolodione polymer

Abstract

The application belongs to the technical field of polymer synthesis and organic photovoltaic cells, and discloses a preparation method of thienopyrrole diketone polymer, which is a three-component polymer containing a TPD unit and prepared by one-step polymerization based on dialdehyde, cyclic imide and elemental sulfur. The polymer has unique optical properties, high molecular weight, and a weight average molecular weight ranging from 5000 to 20000 g / mol. The synthesis method has the advantages of easy raw materials, simple operation steps and few by-products.

Description

Technical Field

[0001] This invention belongs to the field of polymer synthesis technology and organic photovoltaic cells, and relates to a method for constructing thienopyrrole dione (TPD) polymers by three-component polymerization of dialdehyde monomers, elemental sulfur and cyclic imide monomers. Background Technology

[0002] Organic semiconductor materials have advantages such as wide availability, simple preparation, and low cost, and are widely used in solar cells. Developing high-performance photovoltaic materials is one of the important ways to improve the power conversion efficiency (PCE) of solar cells. TPD is an electron-withdrawing material with a symmetrical, compact, rigid fused coplanar structure. Because various functional groups can be introduced into pyrrole sites, the solubility, processability, and energy levels of the synthesized polymers can be controlled (Conjugated Polymers Based on 1,3-Dithien-2-yl-thieno[3,4-c]pyrrole-4,6-dione: Synthesis, Characterization, and Solvent Effects on Photovoltaic Performance). Therefore, donor-acceptor polymers containing TPD units can enhance intra-chain and inter-chain interactions, form quinone-type structures through thiophene-maleimide structures, and stabilize excited-state energy. Therefore, TPD-based polymers will exhibit high open-circuit voltage (VOC). Recently, Leclerc et al. reported the synthesis of an alternating copolymer of dithienothiophene and thienopyrrole-4,6-dione using benzo[1,2-b;3,4-b]dithiophene (BDT) as the electron-donating unit and TPD as the electron-withdrawing unit (Bulk Heterojunction Solar Cells Using Thieno[3,4-c]pyrrole-4,6-dione and Dithieno[3,2-b:2′,3′-d]silole Copolymer with a Power Conversion Efficiency of 7.3%). This polymer was identified as having a PCE of 5.5%, a HOMO level of 5.56 eV, and a VOC of 0.85 V. Reynolds et al. (Dithienogermole As a Fused ElectronDonor in Bulk Heterojunction Solar Cells) obtained a polymer with 7.3% PCE by polymerizing dithiophene germanium and TPD units, and investigated its photophysical properties, thermal stability, electrochemical properties, charge transport capacity, and application in solar cells. Currently, traditional methods for preparing polymers containing TPD units often involve multiple steps, toxic organotin reagents, and residual transition metal catalysts. To address these issues, it is crucial to develop a simple and atom-economical synthetic route to conveniently construct polymers containing TPD structural units. Therefore, we developed a novel multicomponent polymerization reaction based on a three-component system of elemental sulfur cyclic imides and dialdehydes, preparing a novel library of polymers containing TPD units, which is both challenging and significant. Summary of the Invention

[0003] To address the shortcomings of the above technologies, this invention provides a method for constructing TPD-like polymers by polymerizing elemental sulfur, cyclic imide, and dialdehyde in three components. This method has the advantages of producing polymers with high molecular weight, high yield, and well-defined structure.

[0004] The technical solution of this invention:

[0005] A method for preparing a TPD-type polymer includes the following preparation steps:

[0006] Accurately weigh 1 molar equivalent of dialdehyde monomer A, 1 molar equivalent of cyclic imide monomer B, 0.1-0.5 molar equivalent of elemental sulfur (S8), 0.3-1.0 molar equivalent of base, 0.1-0.6 molar equivalent of oxide, and 0.8-1.6 molar equivalent of deionized water, and dissolve them in a solvent to obtain a reaction solution; wherein the reaction concentration of dialdehyde monomer A is controlled at 0.1-0.6 M; the above reaction solution is continuously stirred at 100-150℃ for 3-10 h, and then cooled to room temperature; the crude product is precipitated in methyl tert-butyl ether (MTBE), and the precipitate is collected by centrifugation; the precipitate is redissolved with N,N'-dimethylformamide (DMF), and precipitated again in MTBE, and the above process is repeated three times; after washing the precipitate twice with MTBE, the product is placed in a vacuum drying oven and dried to constant weight;

[0007] The general reaction formula is as follows:

[0008]

[0009] Wherein, R1 is an ether group or an aromatic group of different lengths, and R2 is an alkyl group of different lengths; the degree of polymerization n is greater than 5; the weight-average molecular weight of the obtained polymer ranges from 6000 to 20000 g / mol, and the molecular weight distribution ranges from 1.0 to 1.5.

[0010] The alkali is one or two of cesium carbonate, potassium carbonate, and tetramethylguanidine, mixed in any proportion;

[0011] The oxide is one of tert-butyl peroxide, hydrogen peroxide, and potassium permanganate;

[0012] The solvent is one or more of dimethyl sulfoxide, n-hexane, and DMF, mixed in any proportion.

[0013] The structure of the dialdehyde monomer A is as follows:

[0014]

[0015] The structure of the cyclic imide monomer B is as follows:

[0016]

[0017] The beneficial effects of this invention are:

[0018] (1) This invention proposes a one-step preparation of a three-component polymer containing TPD units based on the three-component polymerization of dialdehyde, cyclic imide and elemental sulfur.

[0019] (2) This type of polymer has unique optical properties and high molecular weight (weight average molecular weight range of 5000-20000 g / mol).

[0020] (3) The synthesis method proposed in this invention has readily available raw materials, simple operation steps, and few by-products. Attached Figure Description

[0021] Figure 1 The image shows the NMR spectrum of the three-component TPD polymer P1 prepared in Example 1 of this invention.

[0022] Figure 2 The image shows the NMR spectrum of the three-component TPD polymer P2 prepared in Example 2 of this invention.

[0023] Figure 3 The image shows the NMR spectrum of the three-component TPD polymer P3 prepared in Example 3 of this invention.

[0024] Figure 4 This is the NMR spectrum of the three-component TPD polymer P4 prepared in Example 4 of the present invention.

[0025] Figure 5 This is the NMR spectrum of the three-component TPD polymer P5 prepared in Example 5 of the present invention.

[0026] Figure 6 This is the NMR spectrum of the three-component TPD polymer P6 prepared in Example 6 of the present invention.

[0027] Figure 7 The image shows the NMR spectrum of the three-component TPD polymer P7 prepared in Example 7 of this invention. Detailed Implementation

[0028] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and technical solutions.

[0029] Example 1

[0030] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in DMF (2 mL) and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE, and this process was repeated three times. After washing the precipitate twice with MTBE, the product was dried in a vacuum drying oven to constant weight to obtain powdered product P1 with a yield of 83%. The molecular weight was 20000 g / mol, and the polydispersity index (PDI) was 1.15.

[0031] Example 2

[0032] Dialdehyde A2 (141.78 mg, 0.4 mmol), cyclic imide B1 (73.3 mg, 0.4 mmol), elemental sulfur (1.92 mg, 0.06 mmol), cesium carbonate (65.16 mg, 0.2 mmol), tert-butyl peroxide (11 μl, 0.08 mmol), and deionized water (9 μl, 0.5 mmol) were dissolved in DMF (4 mL) and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P2 with a yield of 54%. The molecular weight was 9400 g / mol, and the polydispersity index (PDI) was 1.15.

[0033] Example 3

[0034] Dialdehyde A3 (112.13 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in DMF (2 mL) and reacted at 100 °C for 10 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE, and the product was dried in a vacuum drying oven to constant weight to obtain powdered product P3 with a yield of 88%. The molecular weight was 8500 g / mol, and the polydispersity index (PDI) was 1.15.

[0035] Example 4

[0036] Dialdehyde A4 (251.14 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in 2 mL of DMF and reacted at 130 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P4 with a yield of 57%. The molecular weight was 8200 g / mol, and the polydispersity index (PDI) was 1.11.

[0037] Example 5

[0038] Dialdehyde A5 (321.96 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in DMF (2 mL). The reaction was carried out at 150 °C for 3 h, and then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P5 with a yield of 56%. The molecular weight was 9600 g / mol, and the polydispersity index (PDI) was 1.17.

[0039] Example 6

[0040] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B2 (112.94 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in DMF (2 mL) and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P6 with a yield of 77%. The molecular weight was 9500 g / mol, and the polydispersity index (PDI) was 1.15.

[0041] Example 7

[0042] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B3 (157.83 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in DMF (2 mL) and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P7 with a yield of 61%. The molecular weight was 5800 g / mol, and the polydispersity index (PDI) was 1.01.

[0043] Example 8

[0044] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), tetramethylguanidine (46.07 mg, 0.4 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in 1.3 mL of DMF and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P1 with a yield of 65%. The molecular weight was 8700 g / mol, and the polydispersity index (PDI) was 1.50.

[0045] Example 9

[0046] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (16 mg, 0.4 mmol), potassium carbonate (110.42 mg, 0.8 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in DMF (1.3 mL) and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P1 with a yield of 65%. The molecular weight was 7100 g / mol, and the polydispersity index (PDI) was 1.23.

[0047] Example 10

[0048] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.2 mg, 0.1 mmol), cesium carbonate (78.19 mg, 0.24 mmol), tert-butyl peroxide (59 μl, 0.32 mmol), and deionized water (12 μl, 0.64 mmol) were dissolved in 1.3 mL of DMF and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P1 with a yield of 68%. The molecular weight was 6400 g / mol, and the polydispersity index (PDI) was 1.17.

[0049] Example 11

[0050] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), tert-butyl peroxide (88 μl, 0.48 mmol), and deionized water (23 μl, 1.28 mmol) were dissolved in 2 mL of DMF and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P1 with a yield of 43%. The molecular weight was 5100 g / mol, and the polydispersity index (PDI) was 1.45.

[0051] Example 12

[0052] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), potassium permanganate (25.3 mg, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in DMF (2 mL) and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P1 with a yield of 63%. The molecular weight was 5100 g / mol, and the polydispersity index (PDI) was 1.05.

[0053] Example 13

[0054] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), hydrogen peroxide (4 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in 2 mL of DMF and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P1 with a yield of 49%. The molecular weight was 5500 g / mol, and the polydispersity index (PDI) was 1.01.

[0055] Example 14

[0056] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), potassium carbonate (55.28 mg, 0.4 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μL, 1.0 mmol) were dissolved in DMF (2 mL) and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P1 with a yield of 56%. The molecular weight was 7000 g / mol, and the polydispersity index (PDI) was 1.10.

[0057] Example 15

[0058] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in n-hexane (2 mL) and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P1 with a yield of 44%. The molecular weight was 7800 g / mol, and the polydispersity index (PDI) was 1.34.

[0059] Example 16

[0060] Dialdehyde A1 (168.18 mg, 0.8 mmol), cyclic imide B1 (146.6 mg, 0.8 mmol), elemental sulfur (3.84 mg, 0.12 mmol), cesium carbonate (130.33 mg, 0.4 mmol), tert-butyl peroxide (30 μl, 0.16 mmol), and deionized water (18 μl, 1.0 mmol) were dissolved in dimethyl sulfoxide (2 mL) and reacted at 150 °C for 6 h, then cooled to room temperature. The crude product was precipitated in MTBE, and the precipitate was collected by centrifugation. The precipitate was reconstituted with DMF and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE. The product was then dried in a vacuum drying oven to constant weight to obtain powdered product P1 with a yield of 80%. The molecular weight was 7600 g / mol, and the polydispersity index (PDI) was 1.15.

Claims

1. A method for preparing a TPD-type polymer, characterized in that, The preparation steps include the following: Accurately weigh 1 mole of monomer A, 1 mole of cyclic imide monomer B, 0.1-0.5 moles of elemental sulfur S8, 0.3-1.0 moles of base, 0.1-0.6 moles of oxide, and 0.8-1.6 moles of deionized water, and dissolve them in a solvent to obtain a reaction solution; wherein the reaction concentration of monomer A is controlled at 0.1-0.6 M; the above reaction solution is continuously stirred at 100-150 °C for 3-10 h, and then cooled to room temperature; the crude product is precipitated in methyl tert-butyl ether (MTBE), and the precipitate is collected by centrifugation; the precipitate is then used... N,N' The product was redissolved in dimethylformamide (DMF) and precipitated again in MTBE. This process was repeated three times. The precipitate was washed twice with MTBE and then dried in a vacuum oven to constant weight. The general reaction formula is as follows: Wherein, R1 is an ether group or an aromatic group of different lengths, and R2 is an alkyl group of different lengths; the degree of polymerization n is greater than 5; the weight-average molecular weight of the obtained polymer ranges from 6000 to 10000 g / mol, and the molecular weight distribution ranges from 1.0 to 1.

5. The structure of monomer A is: ； The structure of cyclic imide monomer B is as follows: 。 2. The preparation method according to claim 1, characterized in that, The alkali is one or two of cesium carbonate, potassium carbonate, and tetramethylguanidine, mixed in any proportion.

3. The preparation method according to claim 1, characterized in that, The oxide is one of tert-butyl peroxide, hydrogen peroxide, and potassium permanganate.

4. The preparation method according to claim 1, characterized in that, The solvent is one or more of dimethyl sulfoxide, n-hexane, and DMF, mixed in any proportion.

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