Method for synthesizing aromatic amine polymers and aromatic amine polymers

Abstract

A homogeneous and high-purity aromatic amine polymer is obtained. [Solution] The method for synthesizing aromatic amine polymers according to the present invention is characterized by comprising contacting at least one monomer, which is a tertiary aromatic amine, with iodine. The aromatic amine polymer according to the present invention is characterized by being produced by a production method comprising contacting at least one monomer, which is a tertiary aromatic amine, with iodine.

Description

[Technical Field]

[0001] This invention relates to a method for synthesizing aromatic amine polymers and to aromatic amine polymers. [Background technology]

[0002] Aromatic amine polymers are materials that are expected to be used as porous polymers (POPs), which are porous materials composed solely of organic molecules. Porous polymers allow for precise control of pore shape and function based on molecular design.

[0003] Conventionally, methods for synthesizing aromatic amine polymers include electrolytic polymerization, in which aromatic amine monomers are electrochemically oxidized on an electrode (Non-Patent Documents 1 and 2), and chemical polymerization, in which aromatic amine monomers are bonded together using metal salts or metal complexes as oxidizing agents or catalysts (Non-Patent Documents 3 to 7). [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] C. Gu, et. al., Angew. Chem. Int. Ed. Engl. 2005, 54, 13594-13598 [Non-Patent Document 2] A. Yassin, et. al., ChemElectroChem 2014, 1, 1219-1225 [Non-Patent Document 3] Y. Liao, et. al., ACS Appl. Mater. Interfaces 2017, 9, 38390-38400 [Non-Patent Document 4] H. Bildirir, et. al., Chemistry 2014, 20, 9543-9548 [Non-Patent Document 5] B. Bonillo, et. al., Chemistry of Materials 2016, 28, 3469-3480 [Non-Patent Document 6] M. Trunk, et. al., Chemistry 2016, 22, 7179-7183 [Non-Patent Document 7] G. Cheng, et. al., Angew. Chem. Int. Ed. Engl. 2012, 51, 12727-12731 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] In electropolymerization (Non-Patent Documents 1 and 2), it is difficult to maintain a uniform current distribution on the electrodes during the polymerization reaction, which can lead to localized polymerization in areas where the current is concentrated on the electrodes. In addition, scaling up electropolymerization has been difficult.

[0006] In chemical polymerization methods (Non-Patent Documents 3-7), metal components used as oxidizing agents or catalysts sometimes remained as impurities in the resulting aromatic amine polymers. Because of this, conventional synthesis methods for aromatic amine polymers have made it difficult to obtain homogeneous and high-purity aromatic amine polymers.

[0007] Therefore, there is a need for a method for synthesizing aromatic amine polymers that can produce homogeneous and high-purity aromatic amine polymers, and for realizing aromatic amine polymers synthesized by such a method. [Means for solving the problem]

[0008] The method for synthesizing aromatic amine polymers according to the present invention is characterized by comprising contacting at least one monomer, which is a tertiary aromatic amine, with iodine.

[0009] The aromatic amine polymer according to the present invention is characterized by being produced by a production method including bringing at least one monomer which is a tertiary aromatic amine into contact with iodine.

[0010] According to these configurations, an aromatic amine polymer superior to the aromatic amine polymer obtained by a conventional method in terms of homogeneity and purity can be obtained.

[0011] Hereinafter, preferred embodiments of the present invention will be described. However, the scope of the present invention is not limited by the preferred embodiment examples described below.

[0012] As one aspect, the method for synthesizing an aromatic amine polymer according to the present invention preferably includes bringing the monomer into contact with the iodine in a solvent.

[0013] According to this configuration, scale-up is relatively easy.

[0014] As one aspect, the method for synthesizing an aromatic amine polymer according to the present invention preferably includes the solvent containing a chlorine-containing compound.

[0015] According to this configuration, the reaction easily proceeds.

[0016] As one aspect, the method for synthesizing an aromatic amine polymer according to the present invention further preferably includes forming a film containing the monomer on a substrate, and bringing the film into contact with iodine vapor to bring the monomer into contact with the iodine.

[0017] According to this configuration, a film-like aromatic amine polymer can be obtained.

[0018] As one aspect, the method for synthesizing an aromatic amine polymer according to the present invention preferably further includes washing the crude product obtained by bringing the monomer into contact with the iodine with a washing liquid in which both the monomer and the iodine are dissolved.

[0019] According to this configuration, the purity of the aromatic amine polymer can be further increased.

[0020] As one aspect, the method for synthesizing an aromatic amine polymer according to the present invention preferably further includes heating a crude product obtained by bringing the monomer into contact with iodine to 60°C or higher.

[0021] According to this configuration, the purity of the aromatic amine polymer can be further increased.

[0022] As one aspect, the method for synthesizing an aromatic amine polymer according to the present invention preferably has the monomer having three or more reaction points per molecule.

[0023] According to this configuration, the obtained aromatic amine polymer is likely to exhibit properties as an amorphous porous polymer.

[0024] As one aspect, the method for synthesizing an aromatic amine polymer according to the present invention preferably has the monomer being at least one compound selected from the group consisting of triphenylamine, tris(4-biphenylyl)amine, tris[4-(2-thienyl)phenyl]amine, tris[4'-(2-thienyl)-4-biphenylyl]amine, N,N,N',N'-tetraphenylbenzidine, 1,3,5-tris[4-(diphenylamino)phenyl]benzene, and bis(4-phenyl)(2,4,6-trimethylphenyl)amine.

[0025] According to this configuration, an aromatic amine polymer useful as an electrode material, a catalyst, an adsorbent, etc. can be obtained.

[0026] Further features and advantages of the present invention will become more apparent from the following illustrative and non-limiting description of embodiments described with reference to the drawings.

Brief Description of Drawings

[0027] [Figure 1] It is the mass spectrum of poly(triphenylamine) of Synthesis Example 1 in Example 1. [Figure 2] This is the mass spectrum of poly(triphenylamine) from Example 1 and Synthesis Example 2. [Figure 3] This is the mass spectrum of poly(triphenylamine) from Example 1 and Synthesis Example 3. [Figure 4] This is the mass spectrum of poly(triphenylamine) from Example 1 and Synthesis Example 4. [Figure 5] This is the mass spectrum of poly(triphenylamine) from Example 1 and Synthesis Example 5. [Figure 6] This is the mass spectrum of poly(triphenylamine) from Example 1 and Synthesis Example 6. [Figure 7] This is the mass spectrum of poly(triphenylamine) from Example 1 and Synthesis Example 7. [Figure 8] These are the Raman spectra of the poly(triphenylamine) and monomer from Example 1 and Synthesis Example 2. [Figure 9] These are the infrared absorption spectra of poly(triphenylamine) and monomers from Example 1 and Synthesis Example 2. [Figure 10] Examples 1 and 7 show the infrared absorption spectra of poly(triphenylamine) and monomers. [Figure 11] These are the thermogravimetric loss curves of the poly(triphenylamine) and monomers from Example 1 and Synthesis Example 2. [Figure 12] This is the SEM-EDX spectrum of poly(triphenylamine) from Example 1 and Synthesis Example 2. [Figure 13] These are the X-ray diffraction spectra of poly(triphenylamine) and monomers from Example 1 and Synthesis Example 2. [Figure 14] This is the mass spectrum of poly(triphenylamine) from Example 2. [Figure 15] These are the X-ray diffraction spectra of poly(triphenylamine) and monomer from Example 2. [Modes for carrying out the invention]

[0028] The method for synthesizing aromatic amine polymers and embodiments of aromatic amine polymers according to the present invention will be described.

[0029] [Monomers and aromatic amine polymers] The aromatic amine polymer produced in this embodiment is a polymer in which monomers that are tertiary aromatic amines are repeated units. The aromatic amine polymer may be a homopolymer in which a single monomer is repeated unit, or a copolymer in which multiple monomers are repeated units, but it is preferable that it be a homopolymer.

[0030] As an example of an aromatic amine polymer, poly(triphenylamine)(P1) is shown in the following formula. Poly(triphenylamine)(P1) is a homopolymer with triphenylamine(M1) as the monomer. Poly(triphenylamine)(P1) has a structure in which each phenyl group of the triphenylamine unit is bonded to the phenyl group of another triphenylamine unit at the para position. This is due to the fact that the para position of each phenyl group of triphenylamine(M1) has higher substitution activity than the ortho and meta positions. [ka]

[0031] In poly(triphenylamine)(P1), each triphenylamine unit is bonded to other triphenylamine units at three locations. This gives poly(triphenylamine)(P1) a three-dimensional network molecular structure, making it easy to exhibit properties as an amorphous porous polymer (POPs). Amorphous porous polymers have high chemical and thermal stability, as well as a high specific surface area, and are therefore expected to be applied to electrode catalysts and positive electrode active materials for batteries. It is preferable that each repeating unit is bonded to other repeating units at three or more locations, as in the poly(triphenylamine)(P1) described above, because it makes it easier to exhibit properties as an amorphous porous polymer. In other words, it is preferable that each monomer has three or more reaction sites per molecule. Here, "reaction site" refers to an atom in which a bond between monomers occurs when a polymerization reaction proceeds within the range of chemical reactions that a person skilled in the art can ordinarily conceive of, for example, the para position of each phenyl group in triphenylamine(M1).

[0032] Non-limiting examples of monomers include triphenylamine (M1), tris(4-biphenylyl)amine (M2), tris[4-(2-thienyl)phenyl]amine (M3), tris[4'-(2-thienyl)-4-biphenylyl]amine (M4), N,N,N',N'-tetraphenylbenzidine (M5), 1,3,5-tris[4-(diphenylamino)phenyl]benzene (M6), and bis(4-phenyl)(2,4,6-trimethylphenyl)amine (M7). All monomers according to this embodiment, including those exemplified herein, are available as commercially available reagents sold by companies such as Tokyo Chemical Industry Co., Ltd. (Japan) and Merck KGaA (Germany), or as products obtained by known synthesis methods using commercially available reagents as starting materials. [ka]

[0033] In the following explanation, when referring to the monomers exemplified above, they may be abbreviated using the symbols representing each monomer. For example, "monomer M1" means triphenylamine. Also, the homopolymers that use each monomer as a repeating unit are called polymers P1 to P7, respectively. For example, "polymer P1" represents poly(triphenylamine), which is a homopolymer of monomer M1 (triphenylamine).

[0034] Of the examples above, polymers P2, P3, and P4, which are homopolymers of monomers M2, M3, and M4, have a structure in which each repeating unit is bonded to other repeating units at three points, similar to polymer P1. Therefore, polymers P2, P3, and P4, like polymer P1, have a three-dimensional network molecular structure and exhibit the properties of amorphous, porous polymers.

[0035] Monomer M2 has a structure in which three 4-biphenylyl groups are bonded to the nitrogen atom, and the substitution activity is highest at the para position of the terminal phenyl group of each 4-biphenylyl group. Therefore, polymer P2 has a structure in which the para positions of the terminal phenyl groups of each repeating unit are bonded together. In monomers M3 and M4, the substitution activity is highest at the 3 position of the thienyl group bonded to the site furthest from the nitrogen atom, and polymers P3 and P4 have a structure in which the 3 positions of the thienyl groups of each repeating unit are bonded together.

[0036] Polymer P5, a polymer of monomer M5, has a structure in which each repeating unit is bonded to other repeating units at four points. In monomer M5, the substitution activity is highest at the para positions of the four phenyl groups, and polymer P5 has a structure in which the para positions of the phenyl groups of each repeating unit are bonded to each other.

[0037] Polymer P6, a polymer of monomer M6, has a structure in which each repeating unit is bonded to other repeating units at six locations. In monomer M6, the substitution activity is highest at the para positions of the six phenyl groups, and polymer P6 has a structure in which the para positions of the phenyl groups of each repeating unit are bonded to each other.

[0038] Polymer P7, a polymer of monomer M7, has a structure in which each repeating unit is bonded to other repeating units at two locations. In monomer M7, the substitution activity is highest at the para positions of the two phenyl groups, and polymer P7 has a structure in which the para positions of the phenyl groups of each repeating unit are bonded to each other.

[0039] [Method for synthesizing aromatic amine polymers] The method for synthesizing aromatic amine polymers according to this embodiment involves contacting at least one monomer, which is a tertiary aromatic amine, with iodine. The tertiary aromatic amine is oxidized by iodine to generate a radical, and radical polymerization proceeds with the radical as the active species. The monomer may be purified by a known method before contacting it with iodine. Alternatively, the method for synthesizing aromatic amine polymers according to this embodiment may involve purifying the crude product obtained by contacting the monomer with iodine.

[0040] In the following, as specific examples of the synthesis method according to this embodiment, solution polymerization and gas-phase polymerization as examples of means for contacting the monomer with iodine, and the purification of the obtained crude product will be described.

[0041] (1) Solution polymerization In solution polymerization, contact between the monomer and iodine is carried out in a solvent. Examples of solvents used here include, but are not limited to, 1,2-dichloroethane, chlorobenzene, and chloroform. The solvent preferably contains a chlorine-containing compound. Therefore, the solvent preferably contains 1,2-dichloroethane, chlorobenzene, chloroform, etc., and more preferably contains 1,2-dichloroethane. The solvent may be a single compound or a mixture of several compounds.

[0042] The concentration of the monomer in the solvent is not particularly limited, but for example it may be between 0.03 mol / L and 0.1 mol / L. The concentration of iodine in the solvent is not particularly limited, but for example it may be between 0.3 mol / L and 15 mol / L. The molar ratio of monomer to iodine in the solvent is not particularly limited, but for example the concentration of iodine may be between 3 and 500 times the concentration of the monomer.

[0043] The temperature at which the monomer and iodine are brought into contact in the solvent is not particularly limited, but can be, for example, between 50°C and 90°C. From the viewpoint of facilitating the polymerization reaction, a temperature of 60°C or higher is preferable, and 80°C or higher is more preferable. Furthermore, considering that solution polymerization must be carried out at a temperature below the boiling point of the solvent, a temperature of 80°C or lower is preferable, and 60°C or lower is more preferable, from the viewpoint of providing a relatively wide range of solvent options.

[0044] The reaction time when contacting the monomer with iodine in a solvent is not particularly limited, but can be, for example, between 1 hour and 48 hours. As shown in the examples described later, the polymerization reaction in this embodiment proceeds significantly within about 1 hour after the start of the reaction. Therefore, if the reaction time is within the above range, the synthesis of aromatic amine polymers can be carried out under economically advantageous conditions in terms of both yield and required time.

[0045] After contacting (reacting) the monomer with iodine at a predetermined temperature and reaction time, the crude product is separated from the reaction solution. For example, the crude product can be obtained by filtration of the precipitate obtained by adding the reaction solution to a solvent in which the aromatic amine polymer has relatively low solubility.

[0046] (2) Gas phase polymerization method In vapor polymerization, iodine vapor is brought into contact with the monomer. Here, as an example, we will describe a case in which a film containing the monomer is formed on a substrate, and then the film is brought into contact with iodine vapor to bring the monomer into contact with iodine.

[0047] The substrate used when forming a monomer film is not particularly limited, but may include, for example, glass, conductive glass (e.g., transparent glass coated with indium tin oxide (ITO)), glassy carbon, carbon paper, or conductive plastic film (e.g., polyethylene terephthalate film coated with poly(3,4-ethylenedioxythiophene) doped with conductive poly(4-styrene sulfonic acid)). The method for forming the film on the substrate may be a known method, such as spin coating, bar coating, flow coating, or drop casting, but is not limited to these. The monomer may also be dissolved in a solvent when forming the film. Such a solvent is not limited as long as it is a solvent in which the monomer dissolves, but may include, for example, 1,2-dichloroethane, chlorobenzene, or chloroform.

[0048] Contact between the monomer film formed on the substrate and iodine can be carried out by any method. For example, one method involves placing the substrate with the film formed on it into a sealed container filled with iodine vapor. The temperature at which the monomer film and iodine are brought into contact is not particularly limited, as in the case of solution polymerization, and can be, for example, between 80°C and 120°C. From the viewpoint of facilitating the polymerization reaction, a temperature of 90°C or higher is preferable. Furthermore, from the viewpoint of increasing the options for usable substrates and containers, a temperature of 100°C or lower is preferable, and 90°C or lower is more preferable. In the case of the method using a sealed container as exemplified above, for example, the monomer film and iodine vapor can be brought into contact at a predetermined temperature by placing the sealed container into an electric furnace or the like maintained at a predetermined temperature.

[0049] In vapor-phase polymerization, the polymerization reaction proceeds on the substrate, producing a film-like crude product.

[0050] (3) Purification Next, the purification of aromatic amine polymers will be described. The purification methods described below are applicable regardless of the reaction method, as long as they do not contradict the characteristics of the crude product obtained in the reaction step (solution polymerization, gas-phase polymerization, or other methods described above).

[0051] The first purification method to be exemplified is heating. By heating the crude product, any remaining iodine or solvent can be volatilized and removed. The temperature to be heated can be determined by considering, for example, the boiling point of the solvent used as the reaction site (in the case of solution polymerization) or the solvent used during film formation (in the case of gas-phase polymerization), but it can be, for example, 80°C or higher.

[0052] The second example of a purification method is washing with a washing solution. The washing solution is a liquid composition in which both the monomer and iodine are dissolved, and may be, for example, ethanol, methanol, or acetone. Washing with the washing solution may be carried out at room temperature or at a temperature higher than room temperature. The specific method of washing the crude product with the washing solution may be selected according to the form of the crude product. For example, if the crude product is a powder, washing may be carried out by mixing the powder with the washing solution and then filtering it. Also, for example, if the crude product is a film on a substrate, washing may be carried out by immersing the film together with the substrate in the washing solution. It is advisable to remove the washing solution after washing (e.g., by heating and drying, or vacuum drying).

[0053] The heating and washing methods exemplified above, as well as purification methods not exemplified, may be carried out in appropriate combinations.

[0054] [Comparison with conventional synthesis methods] Conventionally known methods for synthesizing aromatic amine polymers include electropolymerization, in which monomers are electrochemically oxidized on an electrode, and chemical polymerization, in which monomers are bonded together using metal salts or metal complexes as oxidizing agents or catalysts.

[0055] In electropolymerization, it is difficult to maintain a uniform distribution of current on the electrodes while the polymerization reaction is progressing, so the polymerization reaction may proceed locally in areas where the current on the electrodes is concentrated. Therefore, when comparing aromatic amine polymers obtained by the synthesis method according to this embodiment with aromatic amine polymers obtained by electropolymerization, the aromatic amine polymer obtained by the synthesis method according to this embodiment is considered to have superior homogeneity as a material. Here, homogeneity refers to homogeneity in terms of the molecular weight and pore configuration of the aromatic amine polymer.

[0056] In chemical polymerization methods, aromatic amine polymers have been synthesized by oxidative coupling using iron chloride or aluminum chloride as an oxidizing agent, or by named reactions (Suzuki-Miyaura coupling, Yamamoto coupling, etc.) using transition metal catalysts. In these methods, metal components used as oxidizing agents or catalysts may remain as impurities in the resulting aromatic amine polymer. Therefore, when comparing aromatic amine polymers obtained by the synthesis method according to this embodiment with aromatic amine polymers obtained by chemical polymerization, the aromatic amine polymer according to this embodiment has superior material purity.

[0057] Thus, the aromatic amine polymer obtained by the synthesis method according to this embodiment is superior to the aromatic amine polymer obtained by conventional methods, at least in terms of homogeneity and purity. Furthermore, in the examples described later, it was confirmed that the aromatic amine polymer obtained by the synthesis method according to this embodiment exhibits a unique gas adsorption behavior not seen in aromatic amine polymers obtained by conventional methods. Although it has been experimentally confirmed that the aromatic amine polymer obtained by the synthesis method according to this embodiment is different as a substance from the aromatic amine polymer obtained by conventional methods, at the time of filing this application, the differences between the two have not been clarified in terms of specific physical properties of the substances themselves.

[0058] [Examples] The present invention will be further described below with reference to examples. However, the following examples are not limiting to the present invention.

[0059] (1) Example 1: Synthesis of aromatic amine polymers by solution polymerization (Synthesis Example 1) To 10 mL of 1,2-dichloroethane, 248.0 mg (1.01 mmol) of triphenylamine and 771.2 mg (3.04 mmol) of iodine were added, and the mixture was stirred at 80°C for 20 hours. The mixture was then added to ethanol. The resulting precipitate was collected and, after filtration and washing with ethanol, 49.3 mg of the product was obtained. The product was a pale green powder.

[0060] (Examples 2-6 of the synthesis) The product was obtained in the same manner as in Example 1, except that one or more of the following conditions were changed: the amount of triphenylamine and iodine used, the type of solvent, and the reaction temperature and time. The conditions and results of the six synthesis examples, including Synthesis Example 1, are shown in Table 1. In the "Solvent" column of Table 1, "DCE" represents 1,2-dichloroethane and "CB" represents chlorobenzene.

[0061] Table 1: Synthesis Examples 1-6 [Table 1]

[0062] (Analysis of composite examples) Mass spectrometry was performed on the products obtained in Synthesis Examples 1-7 using a matrix-assisted laser desorption / ionization time-of-flight mass spectrometer (MALDI-TOFMS) (MALDI-8030, Shimadzu Corporation). The laser output was kept the same for each synthesis example. The mass spectra of each synthesis example are shown in Figures 1-7. In all synthesis examples, fragment peaks with m / z intervals of 245.3 that can be attributed to triphenylamine units were observed. In Synthesis Examples 2, 3, and 6, peaks that can be attributed to triphenylamine 20-mers or more were detected, indicating that aromatic amine polymers with a relatively high degree of polymerization were obtained among Synthesis Examples 1-7. On the other hand, in Synthesis Examples 1 and 4, the dimer peaks were the most prominent, and the largest peak was a dodecamer peak, indicating that aromatic amine polymers with a relatively low degree of polymerization were obtained among Synthesis Examples 1-7.

[0063] The Raman spectra of each monomer and product were measured using a Raman microscope (Renishaw inVia® confocal Raman microscope). The incident light wavelength was set to 532 nm. As a representative example, the Raman spectra of the monomer and product for synthesis example 2 are shown in Figure 8. Comparing the Raman spectra of the monomer and the product, a peak (997 cm²) is attributed to the CH bending vibration of the monosubstituted benzene in the monomer. -1 ) and peaks (1028 cm) attributed to ring deformation vibrations -1 While these peaks were clearly observed in the product, they were hardly seen in the product.

[0064] The infrared absorption spectra of each monomer and product were measured using an FT-IR spectrophotometer (IRSpirit®, Shimadzu Corporation). The FT-IR spectrophotometer used was equipped with an accessory for total internal reflection (ATR). Figure 9 shows the infrared absorption spectra of the monomer and product for synthesis example 2, as a representative example. Comparing the infrared absorption spectra of the monomer and the product, a peak (747 cm²) attributed to the CH bending vibration of the monosubstituted benzene was observed in the monomer. -1) is attenuated in the product, and a peak (819 cm -1 ) attributed to the C-H bending vibration of 1,4-disubstituted benzene appears newly in the product.

[0065] From the analysis of the above Raman spectrum and infrared absorption spectrum, it was shown that the polymerization reaction proceeded with the para position of triphenylamine as the reaction point.

[0066] Also, by comparing the intensity of the peak (747 cm -1 ) attributed to the C-H bending vibration of monosubstituted benzene in the infrared absorption spectrum between the monomer and the product, the difference in the reactivity for each polymerization condition was compared. The spectra obtained by subjecting the infrared absorption spectra of the monomer and the products of Synthesis Examples 1 to 7 to absorbance conversion and normalization treatments are shown in Fig. 10. In Fig. 10, it can be said that the higher the reactivity, the smaller the absorbance peak at 747 cm -1 .

[0067] Comparing Synthesis Examples 1 to 3 with different iodine equivalents, in Synthesis Example 2 using 5 equivalents of iodine and Synthesis Example 3 using 20 equivalents of iodine, compared with Synthesis Example 1 using 3 equivalents of iodine, the absorbance peak at 747 cm -1 was smaller. From the comparison of these synthesis examples, it was found that the higher the iodine equivalent, the easier the polymerization reaction proceeds, but the reactivity is almost saturated around 5 equivalents.

[0068] Comparing Synthesis Example 2 and Synthesis Example 6 with different reaction temperatures, in Synthesis Example 2 reacted at 80 °C, compared with Synthesis Example 6 reacted at 60 °C, the absorbance peak at 747 cm -1 was smaller. From the comparison of these synthesis examples, it was shown that the higher the reaction temperature, the easier the polymerization reaction proceeds.

[0069] Comparing Synthesis Example 2 and Synthesis Example 7 with different solvents, in Synthesis Example 2 using 1,2-dichloroethane, compared with Synthesis Example 7 using chlorobenzene, the absorbance peak at 747 cm -1The absorbance peak was small. A comparison of these synthesis examples showed that polymerization proceeded more easily when using 1,2-dichloroethane than when using chlorobenzene. This is thought to be due to the higher solubility of the monomer and polymer of 1,2-dichloroethane compared to chlorobenzene.

[0070] Thermogravimetric analysis (TGA) was performed on each product obtained in Synthesis Examples 1-7 using a thermal analyzer (Shimadzu Corporation DTG-60A). The atmosphere during measurement was nitrogen, and the heating rate was set to 1°C per minute. As a representative example, the thermogravimetric loss curves for the monomer and product in Synthesis Example 2 are shown in Figure 11. The product showed higher thermal stability than the monomer, and the 5% weight loss temperature of the product was 491°C.

[0071] Energy-dispersive X-ray spectroscopy (SEM-EDX) analysis was performed on each product obtained in Synthesis Examples 1 to 7 using a scanning electron microscope (SU6600, Hitachi High-Tech Corporation). The SEM-EDX spectrum for Synthesis Example 2 is shown in Figure 12 as a representative example. The absence of a peak in the region corresponding to the iodine L line in this spectrum indicates that the residual amount of iodine in the product of Synthesis Example 2 is below the detection limit (0.1 atm%). Furthermore, the absence of peaks originating from metal elements in this spectrum indicates that the metal content of the product of Synthesis Example 2 is below the detection limit (0.1 atm%). For the other synthesis examples not shown, it was confirmed that the iodine and metal content were also below the detection limit (0.1 atm%).

[0072] Powder X-ray diffraction measurements of each product obtained in Synthesis Examples 1 to 7 were performed using a fully automated multi-purpose X-ray diffractometer (SmartLab®, manufactured by Rigaku Corporation). Figure 13 shows the X-ray diffraction spectra of the monomer and product for Synthesis Example 2, as a representative example. No peaks originating from the crystalline structure were observed in the X-ray diffraction spectrum of the product. This indicates that the obtained product has an amorphous structure.

[0073] The BET specific surface area of ​​each product obtained in Synthesis Examples 1-7 was measured using a high-precision gas / vapor adsorption analyzer (BELSORP® MAX X, manufactured by Microtrac-Bel Corporation). The BET specific surface area of ​​each example is shown in Table 2. The BET specific surface area of ​​conventional poly(triphenylamine) obtained by chemical polymerization is 5 m². 2 Considering that the values ​​are approximately / g (Z. Chen et al., J. Polym. Sci, Part A: Polym. Chem. 2018, 56, 2574-2583), it can be said that all synthesis examples showed BET specific surface area values ​​higher than those of conventional techniques.

[0074] Table 2: BET specific surface area [Table 2]

[0075] (2) Example 2: Synthesis of aromatic amine polymers by gas-phase polymerization Triphenylamine was dissolved in 1,2-dichloroethane to obtain a 10 mg / mL solution. 0.4 mL of this solution was applied to a glassy carbon substrate by spin coating to form a triphenylamine film. The spin coating conditions were 1500 rpm and 30 seconds. Subsequently, the substrate with the triphenylamine film was sealed in a sealed container pre-filled with iodine vapor. When this sealed container was heated at 80°C for 1 hour, a dark red film-like crude product was obtained on the substrate. The substrate was removed from the sealed container, washed with ethanol, and then immersed in ethanol overnight. After removing the substrate from the ethanol, it was washed again with ethanol and dried in air at 80°C. The film-like product after washing and drying was colorless.

[0076] The obtained product was subjected to mass spectrometry in the same manner as in Example 1. The mass spectrum of the product is shown in Figure 14. Similar to synthesis examples 1-7 of Example 1, fragment peaks with m / z intervals of 245.3 that can be attributed to triphenylamine units were observed. In this example, peaks that can be attributed to triphenylene dimers to hexamers were detected.

[0077] The obtained product was subjected to powder X-ray diffraction measurements in the same manner as in Example 1. The X-ray diffraction spectra of the monomer and the product are shown in Figure 15. Similar to synthesis examples 1-7 in Example 1, no peaks originating from the crystalline structure were observed in the X-ray diffraction spectrum of the product in this example. This indicates that the obtained product has an amorphous structure.

[0078] [Other Embodiments] With regard to other configurations, the embodiments disclosed herein are illustrative in all respects, and it should be understood that the scope of the present invention is not limited thereto. Those skilled in the art will readily understand that modifications can be made as appropriate without departing from the spirit of the invention. Therefore, other embodiments modified without departing from the spirit of the invention are naturally included within the scope of the present invention. [Industrial applicability]

[0079] This invention can be used as a catalyst, adsorbent, and the like.

Claims

1. A method for synthesizing an aromatic amine polymer, comprising contacting at least one monomer that is a tertiary aromatic amine with iodine.

2. The synthesis method according to claim 1, wherein the monomer and the iodine are brought into contact in a solvent.

3. The synthesis method according to claim 2, wherein the solvent contains a chlorine-containing compound.

4. The method further includes forming a film containing the monomer on a substrate, The synthesis method according to claim 1, wherein the monomer and the iodine are brought into contact by bringing the film and the iodine vapor into contact.

5. The synthesis method according to claim 1, further comprising washing the crude product obtained by contacting the monomer with the iodine with a washing solution in which both the monomer and the iodine are dissolved.

6. The synthesis method according to claim 1, further comprising heating the crude product obtained by contacting the monomer with the iodine to 60°C or higher.

7. The synthesis method according to claim 1, wherein the monomer has three or more reaction sites per molecule.

8. The synthesis method according to any one of claims 1 to 7, wherein the monomer is at least one compound selected from the group consisting of triphenylamine, tris(4-biphenylyl)amine, tris[4-(2-thienyl)phenyl]amine, tris[4'-(2-thienyl)-4-biphenylyl]amine, N,N,N',N'-tetraphenylbenzidine, 1,3,5-tris[4-(diphenylamino)phenyl]benzene, and bis(4-phenyl)(2,4,6-trimethylphenyl)amine.

9. An aromatic amine polymer produced by a manufacturing method comprising contacting at least one monomer that is a tertiary aromatic amine with iodine.

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