Preparation method and modification method of aromatic polythiourea compound
The synthesis of aromatic thioureas via carbon disulfide and multi-aromatic amines in dimethyl sulfoxide, followed by modification with hydrindone ketone, addresses the inefficiencies of existing methods, resulting in high refractive index and mechanically robust optical materials.
Patent Information
- Application Number
- CN202510395917.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-31
- Publication Date
- 2025-07-15
AI Technical Summary
The existing synthesis methods of aromatic polythiourea have problems such as high energy consumption, highly toxic drugs, complex synthesis and low yield, making it difficult to achieve the development of aromatic polythiourea with diverse structures and novel functions.
The polymerization reaction of carbon disulfide and polyvinyl amine compounds in dimethyl sulfoxide is used to combine with ninhydrin for backbone modification to prepare aromatic polythiourea compounds, avoid the use of catalysts and control the reaction conditions.
It has achieved efficient synthesis under low cost and mild conditions, and prepared aromatic polythiourea compounds with high refractive index and luminescent properties, with excellent optical and mechanical properties, suitable for large-scale production.
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Abstract
Description
Technical Field
[0001] The present invention belongs to the fields of polymer chemistry and materials science, and particularly relates to a preparation method and a modification method of aromatic polythiourea compounds. Background Art
[0002] Aromatic polythioureas are a class of classic sulfur-containing polymers, which have excellent properties such as high refractive index, high breakdown strength, and efficient metal coordination ability, and have a wide range of application scenarios in optoelectronic materials and other fields. The existing methods for synthesizing aromatic polythioureas are mainly the reactions of diamine monomers with active sulfur-containing compounds, including sulfur sources such as thiourea, thiophosgene, diisothiocyanate, and carbon disulfide. However, these methods have some disadvantages. For example, the reaction conditions of thiourea monomers and amines require high-energy-consuming microwave assistance; thiophosgene is a highly toxic drug; the synthesis and purification of diisothiocyanate are complex; although carbon disulfide can efficiently synthesize aliphatic polythioureas with aliphatic amine monomers, there are problems such as low molecular weight, low yield, and release of toxic hydrogen sulfide gas in the preparation of aromatic polythioureas. The above factors are not conducive to the development of aromatic polythioureas with diverse structures and novel functions (Adv. Mater., 2013, 25, 1734 - 1738.; J. Mater. Chem. A, 2015, 3, 14845 - 14852.; Macromolecules 2019, 52, 22, 8596–8603).
[0003] The main-chain restructuring chemistry of polymers is an efficient way to edit the main-chain structure of polymers. Different from traditional post-modification, this modification method can construct polymers with new main-chain structures and material functions. The research on the synthesis, function, application, and recycling of aromatic polythioureas has been close to saturation. If it is regarded as a polymer modification precursor for research, it may bring unexpected breakthroughs to the field of sulfur-containing polymers (Nature Reviews Chemistry, 2023, 7, 9, 600 - 615.).
[0004] Therefore, it is of great scientific and industrial value to develop a synthesis method of aromatic polythioureas with simple synthesis, mild conditions, and high reaction efficiency and to achieve the main-chain restructuring of aromatic polythioureas. Summary of the Invention
[0005] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a preparation method and a modification method of aromatic polythiourea compounds.
[0006] In order to achieve the above invention purpose, the present invention provides the following technical solutions:
[0007] The present invention provides a preparation method of aromatic polythiourea compounds, comprising the following steps:
[0008] Carbon disulfide and polyaromatic amine compounds are subjected to a polymerization reaction in dimethyl sulfoxide to obtain aromatic polythiourea compounds.
[0009] Preferably, the molar ratio of carbon disulfide to the aromatic amine functional groups of the polyaromatic amine compounds is 1:2 to 3:2;
[0010] Preferably, the temperature of the polymerization reaction is 60 to 100 °C and the time is 1 to 24 h;
[0011] Preferably, the concentration of the polyaromatic amine compounds in dimethyl sulfoxide is 0.50 to 1.50 mol / L.
[0012] Preferably, the stirring speed of the polymerization reaction is 300 to 500 rpm.
[0013] Preferably, the polyaromatic amine compounds include diaromatic amine compounds, triaromatic amine compounds, and tetraaromatic amine compounds. The reaction formula is shown in Figure 8 .
[0014] Preferably, the polyaromatic amine compounds are selected from one or more of the following:
[0015]
[0016] Preferably, the solution after the polymerization reaction is dissolved in an organic solvent and then added to a precipitant, allowed to stand, filtered, and dried to obtain aromatic polythiourea compounds;
[0017] More preferably, the organic solvent is one or more of dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, and tetrahydrofuran;
[0018] More preferably, the precipitant is a poor solvent;
[0019] Even more preferably, the precipitant is one or both of methanol and ethanol.
[0020] The present invention provides aromatic polythiourea compounds prepared by the above preparation method.
[0021] Preferably, the structural formula of the aromatic polythiourea compounds is as follows:
[0022]
[0023] wherein n is an integer from 2 to 600, and Ar 1 ~Ar 3 are aromatic hydrocarbon groups.
[0024] The present invention provides a modification method for aromatic polythiourea compounds, comprising the following steps:
[0025] React the aromatic polythiourea compound prepared by the above preparation method with ninhydrin in an organic solvent to obtain a polyindenone and thiourea compound.
[0026] Preferably, the molar ratio of the ninhydrin to the thiourea functional group of the aromatic polythiourea compound is 1.1:1 to 2:1;
[0027] Preferably, the concentration of the aromatic polythiourea compound in the organic solvent is 0.10 to 1.50 mol / L in terms of the number of repeating units;
[0028] Preferably, the temperature of the reaction is 60 to 100 °C and the time is 1 to 4 h;
[0029] Preferably, the organic solvent is one or more of dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, and tetrahydrofuran.
[0030] Preferably, the stirring speed of the reaction is 300 to 500 rpm.
[0031] Preferably, add the solution after the reaction to a precipitant, let it stand, filter, and dry to obtain a polyindenone and thiourea compound.
[0032] More preferably, the precipitant is a poor solvent;
[0033] Even more preferably, the precipitant is one or both of methanol and ethanol.
[0034] The present invention provides a polyindenone and thiourea compound prepared by the above modification method.
[0035] Preferably, the structural formula of the polyindenone and thiourea compound is as follows:
[0036]
[0037] wherein n is an integer from 2 to 600, and Ar 4～ Ar 6 is an aromatic hydrocarbon group.
[0038] The present invention provides the application of the aromatic polythiourea compound prepared by the above preparation method or the polyindenone and thiourea compound prepared by the above modification method as a high refractive index material and a luminescent material.
[0039] Compared with the prior art, the present invention has the following advantages and beneficial effects:
[0040] (1) The reaction raw materials used in the preparation method of the present invention can be directly purchased commercially and are inexpensive; the polymerization conditions are mild, the process is simple, the polymerization efficiency is high, and large-scale preparation can be carried out;
[0041] (2) The preparation method of the present invention does not require any catalyst and avoids the generation of hydrogen sulfide;
[0042] (3) The present invention has developed a main-chain modification reaction of aromatic polythiourea through the main-chain editing tool ninhydrin. This reaction is efficient, mild in conditions, simple in process, and can be prepared on a large scale;
[0043] (4) The refractive index of the aromatic polythiourea compound film prepared in the present invention reaches 1.7574@633nm; the refractive index of the polymer obtained by chemically modifying the aromatic polythiourea is 1.7200, and the Abbe number is increased from 16.6 to 19.1. The modified film has a certain toughness, the tensile strength can reach 55.7 MPa, the elongation at break is 66%, and it has luminescent properties and a certain flexibility. Description of the Drawings
[0044] Figure 1 It is a comparison diagram of the nuclear magnetic resonance hydrogen spectrum and carbon spectrum of the aromatic polythiourea compound, polyindanone thiourea compound, and model compound prepared in Example 1 of the present invention in deuterated DMSO.
[0045] Figure 2 It is an infrared absorption spectrum diagram of the aromatic polythiourea compound, polyindanone thiourea compound, and model compound prepared in Example 1 of the present invention.
[0046] Figure 3 It is a relationship spectrum diagram of the refractive index and wavelength of the polymers P1, P2, P1n, and P2n prepared in Examples 1 and 2 of the present invention.
[0047] Figure 4 It is a physical picture of the film formation of the polymers P1 and P1n prepared in Example 1 of the present invention.
[0048] Figure 5 It is a stress-strain tensile diagram of the polymers P1n and P2n prepared in Examples 1 and 2 of the present invention.
[0049] Figure 6 It is a fluorescence spectrum diagram of the polymers P1, P1n, and P2n prepared in Examples 1 and 2 of the present invention.
[0050] Figure 7 It is a fluorescence spectrum diagram of the polymer P2n and the model compound indanone thiourea prepared in Example 2 of the present invention.
[0051] Figure 8 It is a reaction formula of binary aromatic amine compounds, ternary aromatic amine compounds, and quaternary aromatic amine compounds. Detailed Embodiments
[0052] The technical solutions in the embodiments of the present invention will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.
[0053] In the following examples, the molar amount or molar concentration of the polymer is calculated based on the molar amount of the repeating unit of the polymer.
[0054] Example 1
[0055] An aromatic polythiourea compound, whose structural formula is shown as P1:
[0056]
[0057] The described aromatic polythiourea compound is prepared by the direct reaction of carbon disulfide and aromatic diamine in dimethyl sulfoxide, and the reaction formula is as formula (I):
[0058]
[0059] Among them, monomer 2 is 1,4-diaminodiphenylmethane, and the solvent is dimethyl sulfoxide, both of which can be purchased from the market. In this example, they are purchased from Aladdin Industrial Corporation; 1 is carbon disulfide, which can be purchased from the market. In this example, it is purchased from TCI.
[0060] The synthesis steps of the described aromatic polythiourea are as follows: Under an air atmosphere, monomer 1 and monomer 2 are sequentially added to a polymerization tube according to a molar ratio of 1.5:1, and dimethyl sulfoxide is injected until the concentration of monomer 2 is 0.67 mol / L. The temperature is raised to 80 °C, and the temperature is kept constant while stirring at a rate of 400 rpm for 12 h; after the reaction is completed, the reaction mother liquor is dissolved in dimethyl sulfoxide (DMSO), and then it is dropped into methanol, allowed to stand, filtered, and dried to obtain the described aromatic polythiourea compound P1.
[0061] After determination and analysis, the yield of the final product aromatic polythiourea compound P1 is 98%, the number-average molecular weight is 37800 g / mol, and the molecular weight distribution is 1.93.
[0062] To prove the oxidation-promoting effect of dimethyl sulfoxide in the polymerization reaction of carbon disulfide and aromatic diamine, N,N-dimethylformamide (DMF) and N-methylpyrrolidone (NMP) were used as reaction solvents for verification (Table 1). By keeping the concentration of monomer 2 unchanged and adding different proportions of DMF and DMSO, when gradually increasing the solvent proportion of DMSO, the molecular weight and yield of the reaction product showed an obvious upward trend. The yield increased from 40% to 98%, and the number-average molecular weight increased from 4100 g / mol to 37800 g / mol. And in the reaction system with 1 mL or more of DMSO added, sulfur powder or sulfur crystals would precipitate as the reaction proceeded. The atmosphere at the end of the reaction in the reaction system with 1 mL or more of DMSO added was monitored by aqueous silver nitrate solution, and no obvious generation of hydrogen sulfide gas was found, indicating that dimethyl sulfoxide might play an oxidation-promoting role in the reaction system.
[0063] Table 1
[0064]
[0065] The input amount of monomer 2 (2 mmol) and CS2 (3 mmol), the temperature was 80 °C, and the reaction time was 12 h.
[0066] The modified polyindanone-thiourea compound has a structural formula as shown in P1n:
[0067]
[0068] The said polyindanone-thiourea compound is prepared by directly reacting aromatic polythiourea and ninhydrin, and the reaction formula is as formula (II):
[0069]
[0070] Among them, monomer 3 is ninhydrin, and the solvent is dimethyl sulfoxide, both of which can be purchased from the market. In this example, they were purchased from Aladdin Industrial Corporation;
[0071] The synthesis steps of the said polyindanone-thiourea compound are as follows: Under an air atmosphere, polymer P1 and reactant 3 were successively added to a polymerization tube according to a molar ratio of 1:1.5, and dimethyl sulfoxide was injected until the concentration of P1 was 0.5 mol / L. Then the temperature was raised to 80 °C, and the temperature was kept unchanged while stirring at a rate of 400 rpm for 4 h; after the reaction ended, the reaction mother liquor was diluted in dimethyl sulfoxide (DMSO), and then it was dropped into methanol, allowed to stand, filtered, and dried to obtain the said polymer P1n.
[0072] After determination and analysis, the yield of the final product dihydroxy polyindanone-thiourea compound P1n was 96%, the number-average molecular weight was 20100 g / mol, and the molecular weight distribution was 1.36.
[0073] The comparison chart of the 1H NMR spectra of the polythiourea compound and its corresponding monomer is shown in Figure 1 . Compared with the thiourea model compound, in the 1H NMR spectrum of the polythiourea compound P1 ( Figure 1 C in), the chemical shift value of the H in -NH- of the thiourea group is at a low field of 9.66 ppm, which is close to the chemical shift value of 9.42 ppm of the -NH- hydrogen of the thiourea group in the model molecule ( Figure 1 A in). The chemical shift value of the alkyl hydrogen -CH2- connected to the benzene ring is at a high field of 3.87 ppm. There are two sets of aromatic hydrogens on the benzene ring, and their chemical shift values are doublets at 7.36 ppm and 7.18 ppm. Similarly, in the 13C NMR spectrum, for the polythiourea P1 ( Figure 1 G in), the chemical shift value of C═S is at 179.94 ppm, and -CH2- is at 40.88 ppm. For the thiourea model compound ( Figure 1 E in), the chemical shift value of C═S is at 180.66 ppm.
[0074] The comparison chart of the 1H NMR spectra of the polythiourea compound and its modified polymer is shown in Figure 1 . Compared with the thiourea model compound ( Figure 1 A in), the -NH- peak of the thiourea group is not found at 9.42 ppm in the indanone-fused thiourea model compound ( Figure 1 B in), and characteristic peaks of dihydroxy -OH appear at 7.80 ppm and 7.74 ppm. Compared with the polythiourea ( Figure 1 C in), for the poly(indanone-fused thiourea) ( Figure 1 D in), the H in -NH- of the thiourea group at 9.66 ppm disappears, and characteristic peaks of dihydroxy -OH appear at 7.82 ppm and 7.85 ppm. The dihydroxy peaks of the indanone-fused thiourea model compound are at 7.80 ppm and 7.74 ppm, which are close to the characteristic peaks of the polymer. In the 13C NMR spectrum, for the poly(indanone-fused thiourea) ( Figure 1 H in), the chemical shift value of C═S is at 179.61 ppm, and the chemical shift value of C═O is at 194.35 ppm. Its C═S peak is close to the chemical shift value of 179.94 ppm of C═S of the polythiourea.
[0075] The infrared absorption spectrum is shown in Figure 2 . For the polythiourea P1, the stretching vibration absorption peak of the C═S bond is at 1530 cm -1 , and the stretching vibration peak of N-H is at 3254 cm -1 . For the poly(indanone-fused thiourea) N-P1, the stretching vibration absorption peak of the C═S bond is at 1520 cm -1 , and the stretching vibration peak of O-H is at 3600 - 3200 cm -1 .
[0076] Example 2
[0077] An aromatic polythiourea compound, the structural formula of which is shown in P2:
[0078]
[0079] The said polythiourea compound is prepared by the direct reaction of carbon disulfide and aromatic diamine in dimethyl sulfoxide, and the reaction formula is as shown in formula (III):
[0080]
[0081] Among them, monomer 4 is 1,4-diaminodiphenyl ether, and the solvent is dimethyl sulfoxide, both of which can be purchased from the market. In this example, they are purchased from Aladdin; 1 is carbon disulfide, which can be purchased from the market. In this example, it is purchased from the company.
[0082] The synthesis steps of the said polythiourea are as follows: Under an air atmosphere, monomer 1 and monomer 4 are successively added to a polymerization tube according to a molar ratio of 1.5:1, and dimethyl sulfoxide is injected until the concentration of monomer 4 is 0.67 mol / L. The temperature is raised to 80 °C, and the temperature is kept constant while stirring at a rate of 400 rpm for 12 h; after the reaction is completed, the reaction mother liquor is dissolved in dimethyl sulfoxide (DMSO), and then it is dropped into methanol, allowed to stand, filtered, and dried to obtain the said aromatic polythiourea compound P2.
[0083] After determination and analysis, the yield of the final product, the aromatic polythiourea compound P2, is 99%, the number-average molecular weight is 59400 g / mol, and the molecular weight distribution is 1.52.
[0084] The modified polyindenedione thiourea compound, the structural formula of which is shown in P2n:
[0085]
[0086] The said polyindenedione thiourea compound is prepared by the direct reaction of aromatic polythiourea and ninhydrin, and the reaction formula is as shown in formula (IV):
[0087]
[0088] Among them, monomer 3 is ninhydrin, and the solvent is dimethyl sulfoxide, both of which can be purchased from the market. In this example, they are purchased from Aladdin;
[0089] The synthesis steps of the described dihydroxypolyindanone thiourea compound are as follows: Under an air atmosphere, polymer P2 and reactant 3 are sequentially added to a polymerization tube in a molar ratio of 1:1.5. Dimethyl sulfoxide is injected until the concentration of P2 is 0.5 mol / L. The temperature is raised to 80 °C, and the temperature is kept constant while stirring at a rate of 400 rpm for 4 h. After the reaction is completed, the reaction mother liquor is diluted in dimethyl sulfoxide (DMSO), and then it is dropped into methanol, allowed to stand, filtered, and dried to obtain the polymer P2n described above.
[0090] Upon determination and analysis, the yield of the final product, the dihydroxypolyindanone thiourea compound P2n, is 96%, the number-average molecular weight is 33500 g / mol, and the molecular weight distribution is 1.18.
[0091] Example 3
[0092] In Example 1, polymer P1 was spin-coated into a film and tested. 30 mg of polymer P1 was weighed and dissolved in 1 mL of N,N-dimethylacetamide, and then 20 mL of chlorobenzene was added and mixed thoroughly. Then it was filtered through a 0.22 mm nylon filter membrane, and 40 mL of the filtrate was dropped onto a 2.0 cm * 2.0 cm silicon wafer for spin-coating. The selected spin coater model was KW-41, and the rotation speed was 2000 rpm. The prepared film was vacuum-dried for 12 h, and then its refractive index was measured by a variable-angle spectroscopic ellipsometer. The selected instrument model was V-VASE. The wavelength range was 400 - 1700 nm, the film thickness was 157 nm, and the relationship spectrum of its refractive index with wavelength was as Figure 3 shown. The results showed that the refractive index of the polymer P1 film was 1.754 at a wavelength of 590 nm, 1.7455 at 633 nm, and still maintained a high refractive index of 1.7041 at a wavelength of 1700 nm. The polymers P1n, P2, and P2n synthesized in Example 1 and Example 2 were used to prepare polymer films according to the film-forming method of polymer P1, and the refractive index was measured. The refractive index of the P2 polymer film was 1.7574 at 633 nm, and the thickness was 152 nm; the refractive index of the P1n polymer film was 1.7006 at 633 nm, and the thickness was 125 nm. Its Abbe number increased from 16.2 (P1) to 20.9 (P1n); the refractive index of the P2n polymer film was 1.7200 at 633 nm, and the thickness was 133 nm. Its Abbe number increased from 16.6 (P2) to 19.1 (P2n). The above data indicate that polythiourea has excellent optical properties and can adjust the refractive index and Abbe number through main-chain reconstruction.
[0093] Next, the synthesized polymers were used to prepare dumbbell-shaped specimens. Since the film-forming properties of polythioureas P1 and P2 were poor, their mechanical properties could not be tested ( Figure 4), only the mechanical properties after polymer reconstruction were tested. Figure 5 ) Dissolve 600 mg of P1n polymer in 6 mL of N,N-dimethylformamide. After adding the solution to an aluminum foil dish and placing it in a vacuum oven, slowly evacuate the air. Heat it to 120 °C and keep it for 24 hours to obtain a polymer film. Cut the film using an international type-IV dumbbell-shaped spline mold. Then, test the dumbbell-shaped spline through a universal tensile machine. The relationship diagram of stress and strain is as Figure 5 shown. The results show that the tensile strength of polymer P1n is 39.5 MPa and the elongation at break is 33%; the tensile strength of P2n is 55.7 MPa and the elongation at break is 66%. The above data indicate that ninhydrin can be used as an editing tool to adjust the polymer backbone structure and regulate the polymer flexibility, so as to prepare polythiourea derivatives with good tensile properties.
[0094] To test the luminescence spectrum, prepare a DMSO polymer solution with a concentration of 10 -3 mol / L and a DMSO indanethiourea solution with a concentration of 10 -3 mol / L. As Figure 6 shown, aromatic polythiourea P1 has no luminescence property, while the polymer shows luminescence property due to the structural change after the backbone reconstruction. However, there are no obvious chromophores and luminescence units in the polymer and ninhydrin. Therefore, this may be the cluster luminescence phenomenon caused by the interaction between the reconstructed dihydroxy groups and sulfur atoms. The luminescence wavelengths of P1n and P2n are 586 nm and 602 nm. By comparing the luminescence spectra of the model compound indanethiourea and polymer P2n, the luminescence wavelength of the polymer has a certain red shift relative to the small molecule, and the luminescence has a certain enhancement trend. This may be due to the change in the intramolecular aggregation state, resulting in the change of luminescence properties. Finally, it is proved that ninhydrin can be used as a backbone editing tool to construct new functional polymers.
[0095] The above examples show that the refractive index of the film prepared from the polythiourea compounds prepared by the present invention reaches 1.7574, and the Abbe number reaches 16.6, having excellent optical properties; the refractive index of the reconstructed polymer film of polythiourea prepared by the present invention reaches 1.7200, and the Abbe number reaches 20.9. In addition to having good refractive properties, it also has good mechanical properties. The tensile strength can reach 55.7 MPa and the elongation at break is 66%; the modified polymer has certain luminescence properties. And the reaction raw materials of the preparation method of the present invention can be commercially purchased, and the polymerization process is simple, the synthesis conditions are mild, the polymerization efficiency is high, and it can be prepared on a large scale.
[0096] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.
Claims
1. A method for preparing an aromatic polythiourea compound, characterized in that, It includes the following steps: Carbon disulfide and polyaromatic amine compounds are subjected to a polymerization reaction in dimethyl sulfoxide to obtain aromatic polythiourea compounds.
2. The preparation method of the aromatic polythiourea compound according to claim 1, characterized in that The molar ratio of carbon disulfide to the aromatic amine functional groups of the polyaromatic amine compounds is 1:2 to 3:2; The temperature of the polymerization reaction is 60 to 100 °C, and the time is 1 to 24 h; The concentration of the polyaromatic amine compounds in dimethyl sulfoxide is 0.50 to 1.50 mol / L.
3. The preparation method of the aromatic polythiourea compound according to claim 1, wherein, The polyaromatic amine compounds are selected from one or more of the following:
4. The preparation method of the aromatic polythiourea compound according to claim 1, characterized in that, The solution after the polymerization reaction is dissolved in an organic solvent, then added to a precipitant, allowed to stand, filtered, and dried to obtain aromatic polythiourea compounds; The organic solvent is one or more of dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, and tetrahydrofuran; The precipitant is one or both of methanol and ethanol.
5. An aromatic polythiourea compound prepared by the preparation method according to any one of claims 1-4, characterized in that, The structural formula is as follows: Among them, n is an integer from 2 to 600, and Ar 1 ~Ar 3 is an aromatic hydrocarbon group.
6. A modification method of an aromatic polythiourea compound, characterized in that, It includes the following steps: The aromatic polythiourea compounds prepared by the preparation method according to any one of claims 1-4 and ninhydrin are reacted in an organic solvent to obtain polyindenone and thiourea compounds.
7. The modification method of the aromatic polythiourea compound according to claim 6, characterized in that, The molar ratio of ninhydrin to the thiourea functional groups of the aromatic polythiourea compounds is 1.1:1 to 2:1; The concentration of the aromatic polythiourea compounds in the organic solvent is 0.10 to 1.50 mol / L in terms of the number of repeating units; The temperature of the reaction is 60 to 100 °C, and the time is 1 to 4 h; The organic solvent is one or more of dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, and tetrahydrofuran.
8. The modification method of the aromatic polythiourea compound according to claim 6, characterized in that, The solution after the reaction is added to a precipitant, allowed to stand, filtered, and dried to obtain polyindenone and thiourea compounds; The precipitant is one or both of methanol and ethanol.
9. The polyindenone thiourea compound prepared by the modification method according to any one of claims 6-8, characterized in that, The structural formula is as follows: wherein, n is an integer from 2 to 600, and Ar 4～ Ar 6 is an aromatic hydrocarbon group.
10. Use of the aromatic polythiourea compounds prepared by the preparation method according to any one of claims 1-4 or the polyindenone and thiourea compounds prepared by the modification method according to any one of claims 6-8 as high refractive index materials and luminescent materials.