Conjugation-breaking polyperoxynaphthalene bis-spirocyclic compounds, methods of making and use thereof
By preparing conjugated, broken polyoxanthracene bispirocyclic compounds, the stability problem of polymer semiconductor materials was solved, enabling efficient flexible light-emitting displays and information display applications.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NANJING UNIV OF POSTS & TELECOMM
- Filing Date
- 2023-04-28
- Publication Date
- 2026-07-24
AI Technical Summary
Existing polymer semiconductor materials have failed to meet commercial requirements in terms of thermal stability, spectral stability, and device performance, limiting their application in the field of flexible electronics.
Conjugated broken polyoxanthracene bispirocyclic compounds were prepared by linking oxanthracene bispirocyclic units via the Yamamoto coupling condensation reaction, and then processed using a solution method for use in organic light-emitting diode devices.
It improves the thermal and spectral stability of the material, enhances the device's lifespan and luminous efficiency, and is suitable for flexible light-emitting display and information display technologies.
Smart Images
Figure CN116496473B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of organic polymer semiconductor materials technology, specifically relating to a conjugated, fragmented polyoxanthracene bispirocyclic compound, its preparation method, and its applications. Background Technology
[0002] Currently, the semiconductor industry is trending towards flexibility and thinness. Compared to inorganic / organic small-molecule semiconductor materials, polymers have significant advantages in flexible electronics. These advantages include flexibility, thinness, large area, low cost, solution processing capability, high mechanical flexibility, and a wide variety of materials. However, currently, the mainstream commercial semiconductor materials are still inorganic semiconductors. This is because polymer semiconductor materials still have some shortcomings, such as insufficient stability to meet commercial requirements (including thermal stability, spectral stability, and mechanical stability) and lower component performance. Therefore, there is an urgent need to develop new polymer semiconductor materials to address these issues.
[0003] Oxanthracene compounds belong to spirocyclic aromatic hydrocarbons and are an important class of building blocks for organic semiconductors. Their unique non-planar spiroconjugation effect, cross-shaped conformation, and steric hindrance effect can effectively improve the photoelectric performance and device stability of organic semiconductor materials. Oxanthracene polymers, as a special type of conjugated-disruption polymers, exhibit a more pronounced hypersteric effect, effectively reducing chain entanglement strength. Simultaneously, the shorter conjugated chain length is beneficial for deep blue light emission. These characteristics make conjugated-disruption polymers promising for broad applications in organic optoelectronic devices, photovoltaic devices, and catalytic reactions. Summary of the Invention
[0004] The purpose of this invention is to provide a conjugated disrupted polyoxanthracene bispirocyclic compound and its preparation method. The conjugated disrupted polyoxanthracene bispirocyclic compound of this invention has good spectral stability and thermal stability, and high fluorescence quantum efficiency, and can be used as a blue light emitting material in organic light-emitting diode devices.
[0005] The objective of this invention is achieved through the following technical solution:
[0006] A conjugated, fragmented poly(oxanthracene) bispirocyclic compound is obtained by linking bispirocyclic units of oxanthracene via a Yamamoto coupling condensation polymerization reaction. The conjugated, fragmented poly(oxanthracene) bispirocyclic compound has the structure shown in Formula I.
[0007]
[0008] Wherein: R is hydrogen or a straight-chain, branched, cyclic alkyl chain or its alkoxy chain having 1 to 8 carbon atoms.
[0009] Furthermore, the conjugated, disrupted polyoxanthracene bispirocyclic compound has the following structure:
[0010]
[0011] On the other hand, the present invention provides a method for preparing the conjugated, disrupted, polyoxanthracene bispirocyclic compound as described above, the preparation method specifically comprising:
[0012] Step S1: Add 2-bromofluorenone, resorcinol and p-toluenesulfonic acid to a reaction flask, inject toluene under light-protected and nitrogen-protected conditions, then heat the reaction system to 120-130℃ and stir for 12-18 hours to allow the reaction to complete.
[0013] Step S2: After the reaction described in step S1 is completed, cool to room temperature, add potassium carbonate and bromooctane (Br-R) to the reaction solution, set the temperature to 100-120℃ and stir for 12-18 hours, and then separate the monomeric oxane bispirocyclic ring after post-treatment.
[0014] Step S3: Under an inert gas and light-protected environment, bipyridine, bis(1,5-cyclooctadiene)nickel, 1,5-cyclooctadiene, and solvent toluene / N,N-dimethylformamide, along with the dispirocycloanthracene bispirocyclic compound obtained in step S2, were added to a reaction tube and sealed. The temperature was set at 85°C, and the reaction was carried out for 3 days. On the third day, bromobenzene was added to the reaction tube to seal the reaction tube. After the reaction was completed, the polymer product, a conjugated broken poly(dispirocycloanthracene bispirocyclic compound, was obtained by filtration, gravity sedimentation, and Soxhlet extraction.
[0015] Furthermore, the molar ratio of 2-bromofluorenone, resorcinol, and p-toluenesulfonic acid added in step S1 is 1:1.5:3.
[0016] On the other hand, the present invention also provides an application of the conjugated disrupted polyoxanthracene bispirocyclic compound as described above, or the conjugated disrupted polyoxanthracene bispirocyclic compound prepared by the above preparation method, in the fields of organic electroluminescence and organic optical storage.
[0017] Furthermore, particularly the application of the conjugated, broken polyoxanthracene bispirocyclic compound in the light-emitting layer of a light-emitting diode device.
[0018] Furthermore, the conjugated, fragmented polyoxanthracene bispirocyclic compound luminescent layer is prepared using a solution method, specifically a spin coating method. The luminescent layer prepared by the spin coating method has more internal voids and channels, allowing electrons and holes to diffuse more easily, resulting in higher luminous efficiency, better integration with other materials, high stability, and a long lifespan.
[0019] Compared with the prior art, the beneficial effects of the present invention are:
[0020] 1. The conjugated, fragmented polyoxanthracene bispirocyclic compound prepared in this invention has smaller intermolecular spacing, stronger rigidity, and more regular structure. Its strong steric hindrance effectively suppresses π-π stacking interactions between molecules, which is beneficial for the design of amorphous organic semiconductors, thereby improving material stability and extending device lifespan. Thermogravimetric analysis and differential thermal analysis showed that its thermal decomposition temperature reached 439.6℃, exhibiting good thermal stability. Fluorescence quantum efficiency tests showed that its efficiency in solution reached 81%, which is relatively high. After annealing in a nitrogen environment at 220℃ for 10 minutes, its emission spectrum did not show significant changes, indicating that the molecular material has good spectral stability. Furthermore, the OLED device prepared using this compound was successfully lit at 9V, with the maximum emission peak located at 408nm, exhibiting blue-violet light.
[0021] 2. The conjugate-disrupted polyoxanthracene bispirocyclic compound of the present invention is obtained by connecting the bispirocyclic units of oxanthracene through the traditional Yamamoto coupling condensation polymerization reaction. The reaction steps are few, the operation is simple, the material is easy to prepare, and when applied to light-emitting diode devices, it is processed by solution method, which can be widely used in the field of light-emitting display and lighting and new information display technology. Attached Figure Description
[0022] Figure 1 The TG (thermogravimetric) curves of the conjugated, broken polyoxanthracene bispirocyclic compound prepared in Example 1 are shown.
[0023] Figure 2 The DSC (differential scanning calorimetry) curve of the conjugated broken polyoxanthracene bispirocyclic compound prepared in Example 1 is shown.
[0024] Figure 3 GPC (gel permeation chromatography) curve of the conjugated fragmented polyoxanthracene bispirocyclic compound prepared in Example 1;
[0025] Figure 4 The UV absorption and fluorescence emission spectra of the conjugated broken polyoxanthracene bispirocyclic compound prepared in Example 1 in the original film and annealed film states are shown.
[0026] Figure 5 The flexible luminescent thin film on a PDMS substrate formed by the conjugated broken polyoxanthracene bispirocyclic compound in Example 3;
[0027] Figure 6 The voltage-brightness curve of the OLED device of the conjugated broken polyoxanthracene bispirocyclic compound formed in Example 4;
[0028] Figure 7The voltage-current density curves of the OLED device of the conjugated broken polyoxanthracene bispirocyclic compound formed in Example 4 are shown.
[0029] Figure 8 The brightness-external quantum efficiency curve of the OLED device of the conjugated broken polyoxanthracene bispirocyclic compound formed in Example 4;
[0030] Figure 9 The electroluminescence (EL) curves of the OLED device of the conjugated broken polyoxanthracene bispirocyclic compound formed in Example 4 at different voltages are shown. Detailed Implementation
[0031] To enable those skilled in the art to better understand the content of this invention, the embodiments of this invention are described in detail below. These embodiments are implemented based on the technical solution of this invention, and provide detailed implementation methods and specific operation processes. However, the content of this invention is not limited to the following examples.
[0032] The sources of raw materials and reagents involved in the embodiments of this invention are described as follows: the compound materials used were purchased from Aldrich Chemical Co.; the reagents used were purchased from Sinopharm Chemical Reagent Co., Ltd. Unless otherwise stated, no further purification was performed before use.
[0033] This invention provides a conjugated, fragmented polyoxanthracene bispirocyclic compound, which is obtained by linking bispirocyclic units of oxanthracene via Yamamoto coupling condensation polymerization, and its structural formula is as follows:
[0034]
[0035] Wherein: R is hydrogen or a straight-chain, branched, cyclic alkyl chain or its alkoxy chain having 1 to 8 carbon atoms.
[0036] Example 1:
[0037] A conjugated, disrupted, polyoxanthracene bispirocyclic compound of the following formula is prepared by the following method:
[0038]
[0039] Step 1): Add 2-bromofluorenone (2.58 g, 10 mmol), resorcinol (1.65 g, 15 mmol), and p-toluenesulfonic acid (5.6 g, 30 mmol) to a 250 mL two-necked round-bottom reaction flask. Seal the reaction apparatus with a sealing film and rubber stopper, and tightly wrap it with aluminum foil. Evacuate the reaction apparatus and purge with nitrogen three times to ensure the reaction system is anhydrous and oxygen-free. Then, inject dry toluene into the reaction apparatus using a syringe. Place the reaction system in an oil bath and heat to 120°C, stirring for 12 hours.
[0040] Step 2): After the reaction in the previous step was completed and cooled to room temperature, potassium carbonate (8.48 g, 51.52 mmol) and bromooctane (7.46 g, 38.62 mmol) were added sequentially to the reaction solution. The temperature was set to 120 °C and stirred for 18 hours. After the reaction was completed, water was added to quench the reaction system. The reaction solution was extracted multiple times with dichloromethane and water, and the organic layer was retained and thoroughly dried with anhydrous sodium sulfate. Subsequently, the solvent was removed by rotary evaporation and the solution was concentrated. 100-200 mesh silica gel powder was added to the concentrate and stirred. The product was separated by 40 cm silica gel column chromatography with petroleum ether:dichloromethane = 10:1 to obtain a white solid monomeric dioxane bispirocyclic ring with a yield of 46%. 1 HNMR(400MHz,Chloroform-d)δ7.48(d,J=7.6Hz,2H),7.36(d,J=8.1Hz,2H),7.29(dd,J=8.1,1.8Hz,2H),7.20(td,J=7.5,1.1Hz,2H),7.12(td,J= 7.5,1.1Hz,2H),7.07-7.04(m,3H),6.94(d,J=7.6Hz,2H),6.74(d,J=2.5 Hz, 2H), 6.33 (dd, J = 8.7, 2.5 Hz, 2H), 6.19 (d, J = 8.7 Hz, 2H), 5.33 (s, 1H).
[0041]
[0042] Step 3): In a water- and oxygen-free glove box under light-protected conditions, add bipyridine (0.25 g, 1.5 mmol) and bis(1,5-cyclooctadiene) nickel (0.5 g, 1.8 mmol) to a 150 mL reaction tube. Seal the reaction apparatus with sealing film and a rubber stopper, then wrap it tightly with aluminum foil. Remove the reaction tube from the glove box, add 1,5-cyclooctadiene (0.25 mL, 1.8 mmol), and transfer the reaction tube to a constant-temperature oil bath stirrer. Insert a nitrogen balloon and set the temperature to 70°C to begin preheating. Dissolve 0.3 g, 0.3 mmol of oxanthracene bispirocyclic compound in 10 mL of toluene (re-dried using sodium wire) and 2 mL of N,N-dimethylformamide (ultra-dry, molecular sieve packaging). After preheating for half an hour, add the mixed solution, raise the temperature to 85°C, and react for 3 days. On the third day, add 1 mL of bromobenzene to the reaction tube to seal it. After the reaction, the catalyst was initially removed by filtration, followed by multiple washes with tetrahydrofuran. The filtrate was then filtered again using a column packed with neutral alumina, and the eluent was collected. The eluent was concentrated using a rotary evaporator, and methanol was added to the concentrate for gravity sedimentation. After stirring for half an hour, the concentrate was filtered to obtain a powdery crude product. Subsequently, the crude product was subjected to Soxhlet extraction with acetone at 85°C. After 3 days of extraction, the product was vacuum dried to obtain a pale yellow polymerized product, a conjugated, fragmented poly(oxanthracene) bispiral molecule, with a yield of 71%, a molecular weight of Mn = 29787, and a degree of polymerization DPn = 35.
[0043]
[0044] Example 2: Performance Testing
[0045] 1) Thermal analysis and determination
[0046] Thermogravimetric analysis (TGA): The instrument was a NETZSCH STA2500 thermogravimetric analyzer from Germany. The test environment was nitrogen, and the heating scan rate was 10℃ / min, from room temperature to 700℃. Differential scanning calorimetry (DSC): The instrument was a NETZSCH DSC214 differential scanning calorimeter from Germany. The test environment was nitrogen, and the heating scan rate was 10℃ / min, with 2 cycles of testing.
[0047] Figure 1 The TG curve of the conjugated, broken polyoxanthracene bispirocyclic compound prepared in Example 1;
[0048] Figure 2 The DSC curve of the conjugated, broken polyoxanthracene bispirocyclic compound prepared in Example 1 is shown.
[0049] Figure 3 The GPC curve is shown for the conjugated, fragmented, polyoxanthracene bispirocyclic compound prepared in Example 1. Figure 1-3As shown, the thermal decomposition temperature reaches 439.6℃, indicating that it has excellent heat resistance; the DSC test cyclically scanned twice from room temperature to 350℃, and no obvious endothermic or exothermic peaks or glass transition temperature were observed, showing excellent thermal stability; the GPC test showed that its molecular weight Mn = 29787 and degree of polymerization DPn = 35.
[0050] 2) Measurement of photophysical properties
[0051] Ultraviolet-visible absorption spectroscopy (UV) test: The instrument model is PerkinElmer Lamda35 UV-Vis spectrophotometer from the United States;
[0052] Fluorescence emission spectroscopy (PL) testing: The instrument was a Shimadzu RF-6000 fluorescence spectrophotometer. The thin film was prepared using a solution spin-coating technique. A 5 mg / mL chloroform solution of the polymer was prepared, and 60 μL was pipetted onto a quartz slide. The spin-coating speed was 1000 rpm, and the spin-coating time was 30 seconds. The film was then annealed at 220°C for 10 minutes under nitrogen protection. Photoluminescence spectroscopy was measured at the wavelength of maximum ultraviolet absorption.
[0053] Figure 4 The figure shows the UV absorption and fluorescence emission spectra of the conjugated fragmented polyoxanthracene bispirocyclic compound prepared in Example 1 in its original and annealed film states. After annealing at 220°C in a nitrogen atmosphere for 10 minutes, the emission spectrum did not show significant changes.
[0054] Example 3: Preparation of Flexible Light-Emitting Thin Film
[0055] Take the conjugated fragmented polyoxanthracene bispirocyclic compound prepared in Example 1, prepare a 5 mg / mL toluene solution, take 100 μL of the above toluene solution and drop it onto a quartz sheet. After air drying, attach a PDMS (polydimethylsiloxane) flexible substrate to the surface, and then roll it at room temperature using a laminator. Remove the flexible substrate, and the polymer film on the quartz sheet will be successfully transferred to the flexible substrate to obtain a flexible light-emitting polymer film. Figure 5 The image shows a flexible luminescent thin film of a conjugated, disrupted polyoxanthracene bispirocyclic compound on a PDMS substrate.
[0056] Example 4: Fabrication of OLED devices using solution spin coating
[0057] The conjugated, fragmented polyoxanthracene bispirocyclic molecular material designed and prepared in this invention can be applied to light-emitting diode (LED) devices. The specific details of preparing organic light-emitting diode (OLED) devices include:
[0058] Step 1: The indium tin oxide substrate is cleaned in an ultrasonic bath using detergent, acetone, ethanol, dichloromethane and deionized water, and dried in an oven at 120°C for 2 hours.
[0059] Step 2: Based on Step 1, spin coat a 40 nm thick layer of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid) at a spin coating speed of 1500 rpm for 30 seconds, and anneal at 120°C for 20 minutes.
[0060] Step 3: Based on Step 2, dissolve the conjugated disrupted polyoxanthracene bispirocyclic compound prepared in Example 1 in toluene (10 mg / mL), and take 80 μL of the solution to spin coat the light-emitting layer at a spin coating speed of 1500 rpm for 30 seconds. Anneal at 120°C for 20 minutes in a nitrogen atmosphere.
[0061] Step 4: Based on Step 3, 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene, lithium fluoride and aluminum layers are deposited by thermal evaporation to obtain the blue light emitting diode device of the present invention.
[0062] The device structure of the aforementioned blue light-emitting diode is indium tin oxide / poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid) (40nm) / light-emitting layer (50nm) / 1,3,5-tris(1-phenyl-1H-benzimidazol-2-yl)benzene (20nm) / lithium fluoride (1nm) / aluminum (100nm).
[0063] Electroluminescence tests were performed on the fabricated blue light-emitting diode device, such as... Figure 6 and Figure 7 As shown, the OLED device was successfully lit at a voltage of 10V; the efficiency at different brightness levels is as follows. Figure 8 As shown, the external quantum efficiency of the fabricated OLED device is around 0.1%; the electroluminescence (EL) curves at different voltages are shown below. Figure 9 Test results show that its maximum emission peak is 408 nm, and its CIE coordinates are (x = 0.20, y = 0.19), exhibiting blue-violet light emission.
[0064] The above description is only a preferred embodiment of the present invention and is not limited to the above implementation method. Any equivalent modifications, substitutions and improvements made by those skilled in the art based on the content disclosed in the present invention should be included in the protection scope of the claims.
Claims
1. A conjugated, disrupted polyoxanthracene bispirocyclic compound, characterized in that, It has the structure shown in Equation I: Ⅰ； Where: R is hydrogen or a straight-chain, branched, or cyclic alkyl chain with 1 to 8 carbon atoms; n is the degree of polymerization, n=35.
2. The conjugated, disrupted, polyoxanthracene bispirocyclic compound according to claim 1, characterized in that, The conjugated, fragmented, polyoxanthracene bispirocyclic compound has the following structure: 。 3. A method for preparing the conjugated, disrupted, polyoxanthracene bispirocyclic compound as described in claim 2, characterized in that, The preparation method specifically includes: Step S1: Add 2-bromofluorenone, resorcinol and p-toluenesulfonic acid to a reaction flask, inject toluene under light-protected and nitrogen-protected conditions, then heat the reaction system to 120-130 °C and stir for 12-18 hours to allow the reaction to complete. Step S2: After the reaction described in step S1 is completed, cool to room temperature, add potassium carbonate and bromooctane to the reaction solution, set the temperature to 100-120 ℃ and stir for 12-18 hours, and then separate the monomeric oxane bispirocyclic ring after post-treatment. Step S3: Under an inert gas and light-protected environment, bipyridine, bis(1,5-cyclooctadiene)nickel, 1,5-cyclooctadiene, and solvent toluene / N,N-dimethylformamide, along with the dispirocycloanthracene bispirocyclic compound obtained in step S2, were added to a reaction tube and sealed. The temperature was set at 85°C, and the reaction was carried out for 3 days. On the third day, bromobenzene was added to the reaction tube to seal the reaction tube. After the reaction was completed, the polymer product, a conjugated broken poly(dispirocycloanthracene bispirocyclic compound, was obtained by filtration, gravity sedimentation, and Soxhlet extraction.
4. The method for preparing the conjugated, disrupted, polyoxanthracene bispirocyclic compound according to claim 3, characterized in that, The molar ratio of 2-bromofluorenone, resorcinol and p-toluenesulfonic acid added in step S1 is 1:1.5:
3.
5. The application of the conjugated disrupted polyoxanthracene bispirocyclic compound according to any one of claims 1-2 or the conjugated disrupted polyoxanthracene bispirocyclic compound prepared by the method according to any one of claims 3-4 in the fields of organic electroluminescence and organic optical storage.
6. The application of the conjugated, disrupted, polyoxanthracene bispirocyclic compound according to claim 5, characterized in that, This includes the application of the conjugated, broken polyoxanthracene bispirocyclic compound in the light-emitting layer of a light-emitting diode device.
7. The application of the conjugated, disruptive, polyoxanthracene bispirocyclic compound according to claim 6, characterized in that, The light-emitting layer of the conjugated fragmented polyoxanthracene bispirocyclic compound was prepared by a solution method, namely the spin coating method.