A cyano aromatic ether compound, a modified polyarylene ether nitrile, and a method for preparing the same

Abstract

This invention provides a cyano aromatic ether compound, a modified polyarylene ether nitrile, and a method for preparing the same, belonging to the field of polymer materials technology. A method for preparing a cyano aromatic ether compound includes the following steps: mixing p-hydroxybenzonitrile and 2,6-dichlorobenzonitrile, adding a catalyst, and carrying out a nucleophilic substitution reaction in a solvent to synthesize the cyano aromatic ether compound. The cyano aromatic ether compound is used as a crosslinking agent to prepare the modified polyarylene ether nitrile. This invention achieves the goal of using the cyano aromatic ether compound as a crosslinking agent to improve the compatibility with polyarylene ether nitrile and to improve the heat resistance and mechanical properties of the modified polyarylene ether nitrile.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, specifically to a cyano aromatic ether compound, a modified polyarylene ether nitrile, and a method for preparing the same. Background Technology

[0002] Polyarylene ether nitrile (PEN), a high-performance specialty engineering plastic, is widely used in aerospace, electronics, and automotive industries due to its excellent heat resistance, flame retardancy, mechanical properties, and electrical insulation. Its molecular backbone contains arylene bonds and nitrile groups. The arylene bonds impart good processability, while the nitrile groups promote adhesion to the substrate and serve as crosslinking sites.

[0003] However, with the expansion of application areas, especially in extreme high-temperature or high-intensity environments, the heat distortion temperature and solvent resistance of ordinary linear polyarylether nitrile still need improvement. Generally, introducing cross-linking structures is an effective means to improve the heat resistance and dimensional stability of polymers.

[0004] Chinese patent application CN110628014A discloses a method for synthesizing crosslinked polyarylether nitrile. This method focuses on the design of the molecular structure of such polyarylether nitrile, using hydroquinone with an amino group in its side chain as one of the reactant monomers to synthesize hydroxyl-terminated polyarylether nitrile. Then, phthalonitrile is introduced at the end of the molecular backbone to synthesize crosslinkable polyarylether nitrile. Crosslinked polyarylether nitrile films can be obtained using a casting and low-temperature self-crosslinking strategy. The resulting films exhibit excellent thermal, mechanical, and dielectric properties, and can be used as high-temperature resistant dielectric films. However, the mechanical properties of the crosslinked polyarylether nitrile obtained in the above technical solution still need further improvement.

[0005] Currently, crosslinking modification of polyarylene ether nitrile (PAN) is mostly achieved by adding external crosslinking agents. However, traditional crosslinking agents have poor compatibility with the PAN matrix and are prone to migration during processing, leading to uneven material properties. Therefore, developing a crosslinking agent with good compatibility with the PAN matrix, high reactivity, and the ability to effectively improve the overall performance of the material, along with its modification method, is of significant practical importance. Summary of the Invention

[0006] In view of this, the present invention provides a cyano aromatic ether compound, a modified polyarylene ether nitrile and a method for preparing the same, so as to achieve the purpose of using the cyano aromatic ether compound as a crosslinking agent to improve the compatibility with the polyarylene ether nitrile, and to improve the heat resistance and mechanical properties of the modified polyarylene ether nitrile.

[0007] To achieve the above objectives, the present invention provides a cyano aromatic ether compound, wherein the cyano aromatic ether compound has the following structure:

[0008] .

[0009] The cyano aromatic ether compound provided by this invention has similar aryl ether bonds and nitrile groups to the main chain of polyaryl ether nitrile, thus exhibiting strong compatibility with polyaryl ether nitrile. Compared with crosslinking agents in the prior art, it is more uniform in the processing, resulting in more stable material properties.

[0010] The present invention also provides a method for preparing a cyano aromatic ether compound, characterized by comprising the following steps: mixing p-hydroxybenzonitrile and 2,6-dichlorobenzonitrile, adding a catalyst, and carrying out a nucleophilic substitution reaction in a solvent to synthesize a cyano aromatic ether compound.

[0011] In the solution provided by this invention, the phenolic anions of two molecules of p-hydroxybenzonitrile react with one molecule of 2,6-dichlorobenzonitrile to generate a "tricyclic" compound containing two cyano groups and a diphenyl ether structure.

[0012] Optionally, the molar ratio of p-hydroxybenzonitrile to 2,6-dichlorobenzonitrile is (2~2.2):1.

[0013] The molar ratio of p-hydroxybenzonitrile to 2,6-dichlorobenzonitrile provided by this invention avoids resource waste. If the ratio is too high, p-hydroxybenzonitrile will be wasted; if it is too low, the reaction of 2,6-dichlorobenzonitrile will be incomplete, resulting in resource waste.

[0014] Optionally, the nucleophilic substitution reaction is carried out at a temperature of 140-180°C for a reaction time of 4-8 hours.

[0015] The reaction temperature and reaction time provided by this invention improve the conversion rate of the reaction.

[0016] Optionally, the catalyst is one of anhydrous potassium carbonate, sodium carbonate, and lithium carbonate.

[0017] Optionally, the solvent is a mixture of polar aprotic solvent and nonpolar aprotic solvent, wherein the polar aprotic solvent is one or a combination of two or more of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide and sulfolane; and the nonpolar aprotic solvent is toluene.

[0018] This invention uses a polar aprotic solvent, which has a wide solubility range and reduces side reactions.

[0019] The present invention also provides a cyano aromatic ether compound for use as a crosslinking agent in the preparation of modified polyarylether nitrile.

[0020] The cyano aromatic ether compound provided by this invention is applied to the field of preparing crosslinking agents for modified polyarylene ether nitrile, making the crosslinking agent structurally similar to the polyarylene ether nitrile, thereby achieving in-situ crosslinking modification of the polyarylene ether nitrile and improving the material properties of the modified polyarylene ether nitrile.

[0021] This invention also provides a method for preparing modified polyarylene ether nitrile, comprising the following steps: S1. Using 2,6-dichlorobenzonitrile and hydroquinone as monomers and anhydrous potassium carbonate as catalyst, a nucleophilic substitution reaction was carried out in a polar aprotic solvent to synthesize a hydroxyl-terminated polyarylether nitrile prepolymer; then 4-nitrophthalonitrile was added to carry out a capping reaction to obtain a linear polyarylether nitrile with phthalonitrile as the end group. S2. Mix p-hydroxybenzonitrile and 2,6-dichlorobenzonitrile, add a catalyst, and carry out a nucleophilic substitution reaction in a polar aprotic solvent to synthesize cyano aromatic ether compounds; S3. A linear polyarylene ether nitrile is mixed with a cyano aromatic ether compound and heated to undergo a cross-linking reaction to obtain a modified polyarylene ether nitrile.

[0022] In this invention, hydroquinone forms a phenoxy anion under the action of potassium carbonate, which nucleophilically replaces the chlorine on 2,6-dichlorobenzonitrile to form an aromatic ether bond, and gradually polymerizes to generate polyarylether nitrile. Finally, 4-nitrophthalonitrile is added, which has higher activity and can replace the chlorine at the end of the polymer chain, introducing phthalonitrile end groups.

[0023] In this invention, the cyano group in the cyano aromatic ether compound molecule or other active groups (such as triazine ring) generated during the reaction can undergo cross-linking reaction with the nitrile group or end group on the polyarylene ether nitrile molecular chain to form a three-dimensional network structure, thereby improving the mechanical properties and heat resistance of the modified polyarylene ether nitrile.

[0024] Optionally, the mass of the cyano aromatic ether compound is 1 to 15% of the mass of the linear polyarylene ether nitrile.

[0025] The mass ratio of cyano aromatic ether compounds to linear polyarylene ether nitrile provided by this invention reduces raw material waste and lowers costs.

[0026] Optionally, the mass of the cyano aromatic ether compound is 3 to 10% of the mass of the linear polyarylene ether nitrile.

[0027] Optionally, the heating temperature is 300~340℃.

[0028] Optionally, in step S1, the molar ratio of 2,6-dichlorobenzonitrile to hydroquinone is 1:(1~1.08). Optionally, in step S1, the molar amount of 4-nitrophthalonitrile is 1~5% of the molar amount of hydroquinone.

[0029] Optionally, the polar aprotic solvent in step S1 is one or a combination of two or more of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, and sulfolane.

[0030] Optionally, the temperature of the nucleophilic substitution reaction in step S1 is 140~220℃; the reaction time is 4~10h.

[0031] Optionally, the machine used for heating in step S3 is one of an internal mixer, a twin-screw extruder, and a flat vulcanizing machine, and the heating time is 5 to 30 minutes.

[0032] The above-described technical solution of the present invention has at least the following beneficial effects: 1. The cyano aromatic ether compound provided by the present invention and the polyarylether nitrile main chain structure both contain arylether bonds and nitrile groups. As a crosslinking agent, it has excellent compatibility with polyarylether nitrile resin, avoiding the migration and precipitation of the crosslinking agent during the processing.

[0033] 2. The cyano aromatic ether compound provided by this invention contains multiple reactive cyano groups in its molecular structure. It has high reactivity at high temperatures and can effectively form a cross-linked network in the polyarylene ether nitrile matrix. The three-dimensional network structure formed after cross-linking effectively restricts the movement of molecular chains, which significantly increases the glass transition temperature (Tg) and thermal decomposition temperature (Td) of the material. Its heat resistance is better than that of ordinary linear polyarylene ether nitrile, thus improving the material properties of modified polyarylene ether nitrile.

[0034] 3. The preparation method of modified polyarylene ether nitrile provided by the present invention has a simple and controllable process route, is easy to connect with existing processes, does not require complicated treatment, and is easy to industrialize. Attached Figure Description

[0035] Figure 1 The above are the 1H NMR spectrum and chemical structure diagram of the cyano aromatic ether compound in Example 1 of this invention; Figure 2 The image shows the carbon NMR spectrum of the cyano aromatic ether compound in Example 1 of this invention. Figure 3 The above are the 1H NMR spectrum and chemical structure diagram of the linear polyarylene ether nitrile in Example 2 of this invention. Figure 4 This is the carbon NMR spectrum of the linear polyarylether nitrile in Example 2 of the present invention; Figure 5 The triazine ring structure present in the modified polyarylene ether nitrile in Example 2 of this invention; Figure 6 The phthalocyanine ring structure present in the modified polyarylether nitrile in Example 2 of this invention; Figure 7 The above is the 1H NMR spectrum of the modified polyarylene ether nitrile in Example 2 of this invention; Figure 8 This is the carbon NMR spectrum of the modified polyarylether nitrile in Example 2 of the present invention.

[0036] Figure 1The chemical structure in the upper right corner is the structural formula of a cyano aromatic ether compound; Figure 3 The chemical structure in the upper right corner is the structural formula of a linear polyarylene ether nitrile. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following will be described in conjunction with the accompanying drawings of the embodiments of the present invention. Figures 1-5 The technical solutions of the embodiments of the present invention will be clearly and completely described herein. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0038] Example 1 A method for preparing a cyano aromatic ether compound, comprising the following steps: In a 250 mL four-necked flask, 0.2 mol (23.82 g) of p-hydroxybenzonitrile, 0.1 mol (17.20 g) of 2,6-dichlorobenzonitrile, 0.22 mol (30.41 g) of anhydrous potassium carbonate, and 150 mL of N,N-dimethylacetamide (DMAC) were added and mixed. The mixture was heated to 160 °C under nitrogen protection and reacted for 6 hours. After the reaction was complete, the reaction solution was cooled and poured into ice water to precipitate the precipitate. The precipitate was filtered, washed with dilute acid and water until neutral, and dried to obtain a white crystalline powder, i.e., the cyanoaromatic ether compound. The structure was confirmed by 1H NMR and 1C NMR spectroscopy. The 1H NMR spectrum and chemical structure diagram of the cyanoaromatic ether compound are shown below. Figure 1 The carbon NMR spectrum is shown below. Figure 2 .

[0039] Example 2 A method for preparing modified polyarylene ether nitrile includes the following steps: S1. In a 500 mL four-necked flask equipped with a nitrogen inlet, thermometer, mechanical stirrer, and water separator, add 0.5 mol (86.00 g) of 2,6-dichlorobenzonitrile, 0.5 mol (55.05 g) of hydroquinone, 0.5 mol (69.1 g) of anhydrous potassium carbonate, 300 mL of N-methylpyrrolidone (NMP), and 50 mL of toluene. Purge with nitrogen and heat the system to 140 °C under nitrogen protection, then reflux for 2 hours to remove water. After dehydration, begin distilling the toluene; after distilling off the toluene, raise the temperature to 200 °C and maintain the reaction for 6 hours. After the reaction is complete, cool to 100 °C, add 0.015 mol (2.60 g) of 4-nitrophthalonitrile, and continue the reaction for 2 hours to seal the reaction. The reaction solution was poured into methanol to precipitate the precipitate, which was then filtered and repeatedly washed with acetone to remove unreacted monomers. After drying, a pale yellow fibrous linear polyarylene ether nitrile was obtained. The structure was confirmed by 1H NMR and 1C NMR spectroscopy. The 1H NMR spectrum and chemical structure diagram of the linear polyarylene ether nitrile are shown below. Figure 3 The carbon NMR spectrum is shown below. Figure 4 .

[0040] In a 250 mL four-necked flask, 0.2 mol (23.82 g) of p-hydroxybenzonitrile, 0.1 mol (17.20 g) of 2,6-dichlorobenzonitrile, 0.22 mol (30.41 g) of anhydrous potassium carbonate, and 150 mL of N,N-dimethylacetamide (DMAC) were added and mixed. The mixture was heated to 160 °C under nitrogen protection and reacted for 6 hours. After the reaction was completed, the reaction solution was cooled and poured into ice water to precipitate the precipitate. The precipitate was filtered, washed with dilute acid and water until neutral, and dried to obtain a white crystalline powder, which is the cyano aromatic ether compound. S3. Take 100g of the synthesized linear polyarylene ether nitrile, add 5g of crosslinking agent (cyano aromatic ether compound) and 2g of zinc chloride, and mix evenly in a high-speed mixer. Then add the mixture to a twin-screw extruder, heat to induce a crosslinking reaction, extrude and granulate, the heating temperature is 320℃, the heating time is 15min, and the mixture is injection molded into sample strips to obtain modified polyarylene ether nitrile; the product is subjected to performance testing and spectral analysis. The performance test results of the modified polyarylene ether nitrile are shown in Table 1. The structures present in the modified polyarylene ether nitrile include triazine rings (see... Figure 5 ), Phthalocyanine ring (see Figure 6 The proton NMR spectrum of the modified polyarylether nitrile is shown below. Figure 7 The carbon NMR spectrum is shown below. Figure 8 .

[0041] Example 3 The difference from Example 2 is that the mass of the crosslinking agent added in S3 is 10g, while the remaining steps and raw materials are the same as in Example 2.

[0042] Example 4 A method for preparing modified polyarylene ether nitrile includes the following steps: S1. In a 500 mL four-necked flask equipped with a nitrogen inlet, thermometer, mechanical stirrer, and water separator, add 0.5 mol (86.00 g) of 2,6-dichlorobenzonitrile, 0.54 mol (59.46 g) of hydroquinone, 0.54 mol (74.6 g) of anhydrous potassium carbonate, 300 mL of NMP, and 50 mL of toluene. Purge with nitrogen and heat the system to 140 °C under nitrogen protection, then reflux for 2 hours to remove water. After dehydration, distill off the toluene; after distilling off the toluene, heat to 220 °C and maintain the reaction temperature for 4 hours. After the reaction is complete, cool to 110 °C, add 0.005 mol (0.87 g) of 4-nitrophthalonitrile, and continue the reaction for 3 hours to seal the end-capped product. Pour the reaction solution into methanol to precipitate the precipitate, filter, and wash repeatedly with acetone to remove unreacted monomers. After drying, obtain a pale yellow fibrous linear polyarylene ether nitrile.

[0043] In a 250 mL four-necked flask, 0.22 mol (26.21 g) of p-hydroxybenzonitrile, 0.1 mol (17.20 g) of 2,6-dichlorobenzonitrile, 0.22 mol (30.41 g) of anhydrous potassium carbonate, and 150 mL of N,N-dimethylacetamide (DMAC) were added and mixed. The mixture was heated to 140 °C under nitrogen protection and reacted for 8 hours. After the reaction was completed, the reaction solution was cooled and poured into ice water to precipitate the precipitate. The precipitate was filtered, washed with dilute acid and water until neutral, and dried to obtain a white crystalline powder, i.e., the cyano aromatic ether compound. S3. Take 100g of the synthesized linear polyarylene ether nitrile, add 3g of crosslinking agent (cyano aromatic ether compound) and 2g of zinc chloride, and mix evenly in a high-speed mixer. Then add the mixture to a twin-screw extruder, heat to induce a crosslinking reaction, extrude and granulate, the heating temperature is 340℃, the heating time is 5min, and the mixture is injection molded into sample strips to obtain modified polyarylene ether nitrile; the product is subjected to performance testing and spectral analysis, and the performance test results of the modified polyarylene ether nitrile are shown in Table 1.

[0044] Example 5 A method for preparing modified polyarylene ether nitrile includes the following steps: S1. In a 500 mL four-necked flask equipped with a nitrogen inlet, thermometer, mechanical stirrer, and water separator, add 0.5 mol (86.00 g) of 2,6-dichlorobenzonitrile, 0.525 mol (57.81 g) of hydroquinone, 0.5 mol (69.1 g) of anhydrous potassium carbonate, 300 mL of N,N-dimethylformamide (DMF), and 50 mL of toluene. Purge with nitrogen and heat the system to 140 °C under nitrogen protection, then reflux for 2 hours to remove water. After dehydration, begin distilling the toluene; after distilling off the toluene, raise the temperature to 160 °C and maintain the reaction for 10 hours. After the reaction is complete, cool to 90 °C, add 0.025 mol (4.33 g) of 4-nitrophthalonitrile, and continue the reaction for 3 hours to seal the reaction. The reaction solution was poured into methanol to precipitate the precipitate, filtered, and repeatedly washed with acetone to remove unreacted monomers. After drying, a pale yellow fibrous linear polyarylene ether nitrile was obtained.

[0045] In a 250 mL four-necked flask, 0.21 mol (25.02 g) of p-hydroxybenzonitrile, 0.1 mol (17.20 g) of 2,6-dichlorobenzonitrile, 0.22 mol (30.41 g) of anhydrous potassium carbonate, and 150 mL of N,N-dimethylacetamide (DMAC) were added and mixed. The mixture was heated to 180 °C under nitrogen protection and reacted for 4 hours. After the reaction was completed, the reaction solution was cooled and poured into ice water to precipitate the precipitate. The precipitate was filtered, washed with dilute acid and water until neutral, and dried to obtain a white crystalline powder, which is the cyano aromatic ether compound. S3. Take 100g of the synthesized linear polyarylene ether nitrile, add 15g of crosslinking agent (cyano aromatic ether compound) and 2g of zinc chloride, and mix evenly in a high-speed mixer. Then add the mixture to a twin-screw extruder, heat to induce a crosslinking reaction, extrude and granulate, the heating temperature is 300℃, the heating time is 30min, and the mixture is injection molded into sample strips to obtain modified polyarylene ether nitrile; the product is subjected to performance testing and spectral analysis, and the performance test results of the modified polyarylene ether nitrile are shown in Table 1.

[0046] Comparative Example 1 The difference from step S1 in Example 2 is that 4-nitrophthalonitrile is not used for end-capping. All other raw materials and steps are the same, and the operation is as follows: In a 500 mL four-necked flask equipped with a nitrogen inlet, thermometer, mechanical stirrer, and water separator, 0.5 mol (86.00 g) of 2,6-dichlorobenzonitrile, 0.5 mol (55.05 g) of hydroquinone, 0.05 mol (6.91 g) of anhydrous potassium carbonate, 300 mL of NMP, and 50 mL of toluene were added. Nitrogen gas was introduced, and the system was heated to 140 °C under nitrogen protection and refluxed for 2 hours to remove water. After dehydration, toluene was distilled off; after the toluene was distilled off, the temperature was raised to 200 °C and maintained for 6 hours. After the reaction was completed, the reaction solution was poured into methanol to precipitate the precipitate, filtered, and repeatedly washed with acetone to remove unreacted monomers. After drying, a grayish-white linear polyarylene ether nitrile was obtained.

[0047] Comparative Example 2 The linear polyarylene ether nitrile prepared in step S1 of Example 2.

[0048] Comparative Example 3 The only difference from Example 2 is that the existing crosslinking agent phthalonitrile is used instead of the cyano aromatic ether compound for crosslinking, resulting in modified polyarylene ether nitrile.

[0049] The polyarylene ether nitrile prepared in Examples 2-5 and Comparative Examples 1-2 were hot-pressed into standard test strips at 320°C using a flat vulcanizing machine. Their glass transition temperature (Tg, DSC method, heating rate 5°C / min), mechanical properties (GB / T1040, GBT / 1041), and thermodynamic deformation temperature (GB / T1634, load 1.8 MPa) were tested. The results are shown in Table 1.

[0050] Table 1. Performance test results of polyarylene ether nitrile prepared in Examples 2-5 and Comparative Examples 1-2

[0051] As shown in Table 1, the mechanical properties (tensile strength, flexural strength, and elongation at break) of the modified polyarylene ether nitrile prepared in this invention are all higher than those of the polyarylene ether nitrile prepared in the comparative example. The heat resistance (heat distortion temperature and glass transition temperature) of the modified polyarylene ether nitrile prepared in this invention are also higher than those of the polyarylene ether nitrile prepared in the comparative example. In other words, the mechanical properties and heat resistance of the modified polyarylene ether nitrile provided by the preparation method of this invention are further improved.

[0052] As shown in Table 1, the only difference between the modified polyarylene ether nitrile prepared in Example 2 and the polyarylene ether nitrile prepared in Comparative Example 2 is the use of the crosslinking agent (cyano aromatic ether compound) prepared in this invention. The mechanical properties and heat resistance of the modified polyarylene ether nitrile prepared in Example 2 are higher than those of Comparative Example 2. It can be seen that the crosslinking agent prepared in this invention is beneficial to improving the mechanical properties and heat resistance of polyarylene ether nitrile.

[0053] As shown in Table 1, the only difference between the modified polyarylene ether nitrile prepared in Example 2 and the polyarylene ether nitrile prepared in Comparative Example 3 is the use of different crosslinking agents. The mechanical properties and heat resistance of the modified polyarylene ether nitrile prepared in Example 2 are higher than those of Comparative Example 3. It can be seen that the crosslinking agent prepared in this invention is more conducive to improving the mechanical properties and heat resistance of polyarylene ether nitrile than existing crosslinking agents.

[0054] The cyano aromatic ether compound provided by this invention has a structure of three benzene rings connected by two ether bonds to form an aromatic ether skeleton, each with a cyano group. It is highly similar to the structure of the aromatic rings, ether bonds, and side / terminal cyano groups on the main chain of polyarylether nitrile, and has good thermodynamic compatibility.

[0055] The above are preferred embodiments of the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A cyano aromatic ether compound, characterized in that, The cyano aromatic ether compound has the following structure: 。 2. A method for preparing the cyano aromatic ether compound as described in claim 1, characterized in that, Includes the following steps: A nucleophilic substitution reaction was carried out in a solvent by mixing p-hydroxybenzonitrile and 2,6-dichlorobenzonitrile, adding a catalyst, to synthesize cyano aromatic ether compounds.

3. The method for preparing the cyanoaromatic ether compound according to claim 1, characterized in that, The molar ratio of p-hydroxybenzonitrile to 2,6-dichlorobenzonitrile is (2~2.2):

1.

4. The method for preparing the cyanoaromatic ether compound according to claim 1, characterized in that, The nucleophilic substitution reaction is carried out at a temperature of 140~180℃ for a reaction time of 4~8h.

5. The method for preparing the cyanoaromatic ether compound according to claim 1, characterized in that, The catalyst is one of anhydrous potassium carbonate, sodium carbonate, and lithium carbonate.

6. The method for preparing the cyanoaromatic ether compound according to claim 1, characterized in that, The solvent is a mixture of polar aprotic solvent and nonpolar aprotic solvent. The polar aprotic solvent is one or a combination of two or more of N-methylpyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide and sulfolane; the nonpolar aprotic solvent is toluene.

7. The cyano aromatic ether compound as described in claim 1 is applied to the field of crosslinking agents for preparing modified polyarylether nitrile.

8. A method for preparing modified polyarylene ether nitrile, characterized in that, Includes the following steps: S1. Using 2,6-dichlorobenzonitrile and hydroquinone as monomers and anhydrous potassium carbonate as catalyst, a nucleophilic substitution reaction was carried out in a polar aprotic solvent to synthesize a hydroxyl-terminated polyarylether nitrile prepolymer; then 4-nitrophthalonitrile was added to carry out a capping reaction to obtain a linear polyarylether nitrile with phthalonitrile as the end group. S2. Mix p-hydroxybenzonitrile and 2,6-dichlorobenzonitrile, add a catalyst, and carry out a nucleophilic substitution reaction in a polar aprotic solvent to synthesize cyano aromatic ether compounds; S3. A linear polyarylene ether nitrile is mixed with a cyano aromatic ether compound and heated to undergo a crosslinking reaction, thereby obtaining a modified polyarylene ether nitrile.

9. The method for preparing modified polyarylene ether nitrile according to claim 8, characterized in that, The mass of the cyano aromatic ether compound is 1 to 15% of the mass of the linear polyarylene ether nitrile.

10. The method for preparing modified polyarylene ether nitrile according to claim 8, characterized in that, The heating temperature is 300~340℃.

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