A green preparation method and application of furanyl polyamide suitable for industrial production

Abstract

This invention provides a green preparation method and application of furanyl polyamide suitable for industrial production. Steps: S1, Obtaining the main reaction solution: Under inert gas protection, furanyl diacid monomer is added to an organic solvent to form a homogeneous suspension, obtaining the main reaction solution; S2, Obtaining furanyl polyamide: The main reaction solution is cooled to 0℃~25℃, a catalyst is added, and the mixture is stirred for activation. The catalyst is 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride (DMT-MM); a diamine monomer is dissolved in the same organic solvent as the main reaction solution to prepare a diamine solution; the diamine solution is added to the main reaction solution, and after the reaction is complete, the product is separated to obtain furanyl polyamide. Advantages: Sustainable development using biomass diacid monomer as raw material; organic catalyst avoids metal residue, poses no risk of oxidation to the furan ring, and does not damage the monomer structure; mild reaction conditions, simple operation, and easy separation and purification of by-products.

Description

Technical Field

[0001] This invention belongs to the field of bio-based polymer materials technology, and relates to a green preparation method for bio-based polyamides, particularly a green preparation method for furanyl polyamides suitable for industrial production. Background Technology

[0002] Polyamide is a widely used engineering plastic in machinery, automotive, electrical appliances, textile equipment, chemical equipment, aerospace, and metallurgy. With increasing awareness of environmental protection and sustainable development, furanyl polyamide has received significant attention, and the U.S. Department of Energy has listed it as one of the twelve most promising bio-based platform compounds.

[0003] Compared with petroleum-based polyamides, furan-based polyamides have the following advantages: (1) The monomer 2,5-furandicarboxylic acid is derived from renewable biomass, making it environmentally friendly. (2) Furandicarboxylic acid is a five-membered aromatic ring, and its structure and thermal properties are similar to those of terephthalic acid. However, due to the oxygen atom in the furan ring, the intermolecular hydrogen bonding force is reduced and the van der Waals force is enhanced, thus significantly improving its solubility and processability. (3) The introduction of oxygen atoms greatly enhances the coloring properties of furan-based polyamides, which is particularly beneficial for applications in the fiber industry. These characteristics make furan-based polyamides considered to have excellent development potential and application prospects.

[0004] There are existing methods for preparing furanyl polyamides, but all of them have problems: (1) CN105801843A discloses a semi-biomass furanyl soluble aromatic polyamide and its preparation method and application. It uses furanyl dicarboxylic acid monomers that can be derived from biomaterials. The basic monomers are furanyl dicarboxylic acid or its derivatives and p-phenylenediamine. Inorganic metal salts are required as catalysts in the synthesis. However, inorganic metal salts such as LiCl are difficult to completely remove in the reaction system. The residual inorganic salts will reduce the mechanical properties of the polyamide product. Its synthesis needs to be completed in multiple steps at 90-130℃ (i.e., the preparation process is complicated), and the number average molecular weight of the aromatic polyamide obtained is low (less than 200,000). (2) CN112661957A discloses a green synthesis method for furanyl polyamide. This method uses 6-chlorobenzotriazole-1,1,3,3-tetramethylurea hexafluorophosphate (HCTU) as a catalyst, which to some extent overcomes the adverse effects of traditional inorganic metal salt residues on polymer properties. However, this catalyst system still has significant limitations: the hexafluorophosphate ion (PF6) in its molecular structure... -During the reaction, the catalyst may weakly interact with the electron-rich furan ring, potentially interfering with the monomer's reactivity and affecting polymerization efficiency. This can also lead to trace amounts of catalyst components remaining in the final product. Using fine separation methods such as chromatography significantly increases the complexity of the process and the overall cost. Furthermore, the synthetic route of HCTU itself is relatively complex, and the raw material costs are high, further limiting the application prospects of this method in large-scale industrial production.

[0005] Therefore, there is an urgent need for a method for preparing furanyl polyamide suitable for industrial production. Summary of the Invention

[0006] In order to solve the above-mentioned technical problems, the purpose of this invention is to: (1) provide a green preparation method of furanyl polyamide suitable for industrial production; (2) provide the application of furanyl polyamide prepared by the above-mentioned green preparation method of furanyl polyamide suitable for industrial production.

[0007] To achieve the above-mentioned objectives, this invention provides a green preparation method for furanyl polyamide suitable for industrial production, comprising the following steps:

[0008] S1. Obtaining the main reaction solution: Under inert gas protection, furan diacid monomer is added to an organic solvent and stirred at room temperature until a homogeneous suspension is formed, or heated to 40℃~60℃ to assist in dissolution and form a homogeneous suspension, thereby obtaining the main reaction solution; wherein the furan diacid monomer is a furan-based core monomer or a mixture of comonomers composed of a furan-based core monomer and a second type of diacid; the organic solvent is at least one of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methylpyrrolidone (NMP), and acetonitrile;

[0009] S2. Obtaining furanyl polyamide: Under continuous inert gas protection and stirring, the main reaction solution is cooled to 0℃~25℃, a catalyst is added, and the mixture is stirred and activated. The catalyst is 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride (DMT-MM), and the molar ratio of the catalyst to the diacid monomer is (1.05:1)~(1.5:1). The diamine monomer is dissolved in the same organic solvent as the main reaction solution to prepare a diamine solution. The diamine monomer is selected from aromatic diamines or aliphatic diamines, and the mass ratio of the organic solvent to the diamine monomer in the diamine solution is (1:1)~(3:1). The diamine solution is added dropwise to the main reaction solution, and the temperature is maintained at 0℃~25℃. After the addition is completed, the reaction continues under stirring. After the reaction is completed, the product is separated to obtain furanyl polyamide.

[0010] Furthermore, in the green preparation method of furan-based polyamide suitable for industrial production provided by the present invention, the core monomer of furan is substituted or unsubstituted furan dicarboxylic acid; the substituent is C1-C4 alkyl.

[0011] Furthermore, in the green preparation method of furan-based polyamide suitable for industrial production provided by the present invention, the core monomer of furan is 2,5-furandicarboxylic acid.

[0012] Furthermore, in the green preparation method of furan-based polyamide suitable for industrial production provided by the present invention, the molar ratio of furan-based core monomer to second diacid in the comonomer mixture is 9:1 to 1:9; the second diacid is one of terephthalic acid, isophthalic acid, adipic acid, azelaic acid, and dodecanoic acid.

[0013] Furthermore, in the green preparation method of furan-based polyamide suitable for industrial production provided by the present invention, the molar ratio of furan-based core monomer to second diacid in the comonomer mixture is 4:1 to 1:4.

[0014] Furthermore, in the green preparation method of furanyl polyamide suitable for industrial production provided by the present invention, the aromatic diamine is any one of 4,4'-diaminodiphenyl ether, p-phenylenediamine, m-phenylenediamine, and 4,4-diaminodiphenylmethane; the aliphatic diamine is any one of 1,6-hexanediamine, 1,3-propanediamine, and 1,4-butanediamine.

[0015] Furthermore, in the green preparation method of furanyl polyamide suitable for industrial production provided by the present invention, the mass ratio of organic solvent to diamine monomer in the main reaction solution is (4:1) to (8:1).

[0016] Furthermore, in the green preparation method of furanyl polyamide suitable for industrial production provided by the present invention, the molar ratio of furanyl dicarboxylic acid monomer to diamine monomer is (1:0.98) to (1:1.02).

[0017] Furthermore, in the green preparation method of furanyl polyamide suitable for industrial production provided by the present invention, the product separation adopts water washing → vacuum filtration / centrifugation → drying.

[0018] To achieve the above-mentioned objectives, this invention also provides applications of furanyl polyamide prepared according to any of the above-mentioned green preparation methods suitable for industrial production, which are applied to any of the fields of fibers, membrane materials, and nanoparticle / polymer composite materials.

[0019] Compared with existing technologies, the green preparation method of furanyl polyamide suitable for industrial production provided by this invention has the following technical effects: (1) It uses diacid monomers derived from biomass as raw materials, which is in line with the concept of green and sustainable development. (2) In the synthesis process, the organic catalyst 4-(4,6-dimethoxy-1,3,5-triazine-2-yl)-4-methylmorpholine chloride is used to replace the traditional inorganic metal salt catalyst, which effectively avoids the adverse effects of metal residues on polymer performance, and it has no risk of oxidation of furan ring (electron-rich heterocycle) and does not damage the monomer structure. (3) The process reaction conditions are mild and can be carried out at room temperature and pressure. (4) The operation is simple, the by-products are highly water-soluble, easy to separate and purify, and significantly reduce the post-processing cost. (5) The obtained furanyl polyamide has excellent thermodynamic and mechanical properties and is suitable for a variety of high-end application fields such as fibers, membrane materials and nanoparticle / polymer composite materials. Detailed Implementation

[0020] In order to overcome the problems of existing furanyl polyamide preparation methods, such as difficulty in removing catalysts, residual catalysts affecting the mechanical properties of polyamide products, complex preparation processes, low polymerization efficiency, and high costs, this invention aims to provide a green preparation method for furanyl polyamide suitable for industrial production.

[0021] The inventive concept of this invention is to select a catalyst with high catalytic efficiency, good compatibility with furan monomers, easy residue removal, and controllable cost to achieve efficient synthesis of furan-based polyamides under mild reaction conditions, while ensuring that the product has excellent thermodynamic and mechanical properties to meet the needs of industrial production and the application requirements of various fields for high-performance bio-based polyamide materials.

[0022] This invention provides a method for preparing furanyl polyamide suitable for industrial production, comprising the following steps:

[0023] S1. Preparation of the main reaction solution: Under the protection of an inert gas, furanyl diacid monomer is added to an organic solvent and stirred at 200-500 r / min at room temperature until a homogeneous suspension is formed or heated to 40℃-60℃ to assist in dissolution, thereby obtaining the main reaction solution;

[0024] S2. Obtaining furanyl polyamide: Under continuous inert gas protection and stirring at 200–500 r / min, the main reaction solution is cooled to 0°C–25°C, and then a catalyst is added and stirred to activate it. The diamine monomer is dissolved in the same organic solvent as the main reaction solution to prepare a diamine solution, with the mass ratio of organic solvent to diamine monomer being (1:1)–(3:1). The diamine solution is added dropwise to the reaction system, and the feeding rate is controlled to maintain the system temperature at 0°C–25°C. After the feeding is completed, the reaction continues under stirring. After the reaction is completed, the product is separated to obtain furanyl polyamide.

[0025] Regarding furan diacid monomers: Furan diacid monomers are furan-based core monomers or a mixture of comonomers composed of furan-based core monomers and a second diacid. The furan-based core monomer is a substituted or unsubstituted furan diacid, wherein the substituent is a C1-C4 alkyl group; preferably, the furan-based core monomer is 2,5-furan diacid. The comonomer mixture consists of two monomers, one of which is a furan-based core monomer, and the other is one of terephthalic acid, isophthalic acid, adipic acid, azelaic acid, or dodecanoic acid; when the furan diacid monomer is a comonomer mixture, the molar ratio of the furan-based core monomer to the second diacid is 9:1 to 1:9, preferably 4:1 to 1:4.

[0026] Regarding the organic solvent: The organic solvent is at least one of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methylpyrrolidone (NMP), and acetonitrile, and the mass ratio of the organic solvent to the diamine monomer in the main reaction system is (4:1) to (8:1).

[0027] Regarding the catalyst: The catalyst is 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride (DMT-MM). The molar ratio of catalyst to diacid monomer is (1.05:1) to (1.5:1).

[0028] Regarding the diamine monomer. The diamine monomer is selected from aromatic diamines or aliphatic diamines; wherein, the aromatic diamine is any one of 4,4'-diaminodiphenyl ether, p-phenylenediamine, m-phenylenediamine, and 4,4-diaminodiphenylmethane; the aliphatic diamine is any one of 1,6-hexanediamine, 1,3-propanediamine, and 1,4-butanediamine; the molar ratio of furanyl bisacrylic acid monomer to diamine monomer is (1:0.98) to (1:1.02).

[0029] Regarding the selection of process parameters in the green preparation method: The polymerization reaction time is 2~12h. Product separation involves water washing → filtration / centrifugation → drying. If high-purity purification is required, a second water washing-ultrafiltration-drying step can be performed.

[0030] The furanyl polyamide prepared by the above-mentioned green preparation method suitable for industrial production can be applied to any field of fiber, membrane material, and nanoparticle / polymer composite material.

[0031] Example 1

[0032] All chemical reagents used in this embodiment are commercially available. In this embodiment, the diamine is 4,4'-diaminodiphenyl ether, the organic solvent is N,N-dimethylformamide, the diacid is 2,5-furandicarboxylic acid, and the catalyst is 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride. The furanyl polyamide is prepared according to the following steps:

[0033] S1. Under nitrogen protection, 1.00 mol of 2,5-furandicarboxylic acid was added to DMF (the mass ratio of the main system solvent to the diamine was 6:1), and stirred at 350 r / min at room temperature until a homogeneous suspension was formed to obtain the main reaction solution.

[0034] S2. Under continuous nitrogen protection and stirring at 350 r / min, the main reaction solution was cooled to 15℃, and 1.25 mol DMT-MM was added for stirring and activation. 1.00 mol 4,4'-diaminodiphenyl ether was dissolved in DMF (solvent to diamine mass ratio of 1:1) to prepare a diamine solution, which was added dropwise to the reaction system, and the addition rate was controlled to maintain the system temperature at 15℃. After the addition was completed, the reaction was stirred at 350 r / min for 6 h. After the reaction was completed, the product was separated by washing with water, filtration, and vacuum drying to obtain furanyl polyamide.

[0035] The resulting furanyl polyamide has a tensile strength of 108.5 MPa, an elongation at break of 10.5%, and a thermal decomposition temperature (Td, 5%) of 386 °C with 5% mass loss.

[0036] Example 2

[0037] All chemical reagents used in this embodiment are commercially available. In this embodiment, p-phenylenediamine is used as the diamine, N-methylpyrrolidone is used as the organic solvent, 2,5-furandicarboxylic acid and terephthalic acid are used as the diacids, and 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride is used as the catalyst. The furanyl polyamide is prepared according to the following steps:

[0038] S1. Under nitrogen protection, 0.90 mol of 2,5-furandicarboxylic acid and 0.10 mol of terephthalic acid were added to NMP (the mass ratio of the main system solvent to the diamine was 8:1), and heated to 60 °C with stirring at 500 r / min to assist dissolution, thus obtaining the main reaction solution;

[0039] S2. Under continuous nitrogen protection and stirring at 500 r / min, the main reaction solution was cooled to 25°C, and 1.50 mol DMT-MM was added for stirring and activation. 1.02 mol p-phenylenediamine was dissolved in NMP (solvent to diamine mass ratio of 3:1) to prepare a diamine solution, which was added dropwise to the reaction system, and the addition rate was controlled to maintain the system temperature at 25°C. After the addition was completed, the reaction was stirred at 500 r / min for 12 h. After the reaction was completed, the product was separated by washing with water, centrifugation, and vacuum drying to obtain furanyl polyamide.

[0040] The resulting furanyl polyamide has a tensile strength of 116 MPa, an elongation at break of 8.2%, and a thermal decomposition temperature (Td, 5%) of 395 °C with 5% mass loss.

[0041] Example 3

[0042] All chemical reagents used in this embodiment are commercially available. In this embodiment, the diamine used is 1,6-hexanediamine, the organic solvent is N,N-dimethylacetamide, the diacids are 2,5-furandicarboxylic acid and adipic acid, and the catalyst is 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride. The furanyl polyamide is prepared according to the following steps:

[0043] S1. Under nitrogen protection, 0.10 mol of 2,5-furandicarboxylic acid and 0.90 mol of adipic acid were added to DMAc (the mass ratio of the main system solvent to the diamine was 4:1), and stirred at 200 r / min at room temperature until completely dissolved to obtain the main reaction solution.

[0044] S2. Under continuous nitrogen protection and stirring at 200 r / min, the main reaction solution was cooled to 0℃, and 1.05 mol DMT-MM was added for stirring and activation. 0.98 mol 1,6-hexanediamine was dissolved in DMAc (solvent to diamine mass ratio of 1:1) to prepare a diamine solution, which was added dropwise to the reaction system, and the addition rate was controlled to maintain the system temperature at 0℃. After the addition was completed, the reaction was stirred at 200 r / min for 2 h. After the reaction was completed, the product was separated by water washing, vacuum filtration, secondary water washing, ultrafiltration, and vacuum drying to obtain high-purity furanyl polyamide.

[0045] The resulting furanyl polyamide has a tensile strength of 75 MPa, an elongation at break of 18.5%, and a thermal decomposition temperature (Td, 5%) of 345 °C with 5% mass loss.

[0046] Example 4

[0047] All chemical reagents used in this embodiment are commercially available. In this embodiment, the diamine used is 4,4-diaminodiphenylmethane, the organic solvent is DMF, the diacids are 2,5-furandicarboxylic acid and isophthalic acid, and the catalyst is 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride. The furanyl polyamide is prepared according to the following steps:

[0048] S1. Under nitrogen protection, 0.60 mol of 2,5-furandicarboxylic acid and 0.40 mol of isophthalic acid were added to DMF (the mass ratio of the main system solvent to the diamine was 6:1), and the mixture was heated to 50 °C with stirring at 400 r / min to assist in dissolution, thus obtaining the main reaction solution.

[0049] S2. Under continuous nitrogen protection and stirring at 400 r / min, the main reaction solution was cooled to 20℃, and 1.30 mol DMT-MM was added for stirring and activation. 1.00 mol 4,4-diaminodiphenylmethane was dissolved in DMF (solvent to diamine mass ratio of 2:1) to prepare a diamine solution, which was added dropwise to the reaction system, and the addition rate was controlled to maintain the system temperature at 20℃. After the addition was completed, the reaction was stirred at 400 r / min for 8 h. After the reaction was completed, the product was separated by washing with water, centrifugation, and vacuum drying to obtain furanyl polyamide.

[0050] The resulting furanyl polyamide has a tensile strength of 101 MPa, an elongation at break of 9.8%, and a thermal decomposition temperature (Td, 5%) of 378 °C with 5% mass loss.

[0051] Example 5

[0052] All chemical reagents used in this embodiment are commercially available. In this embodiment, 1,3-propanediamine was selected as the diamine, DMAc as the organic solvent, 2,5-furandicarboxylic acid and azelaic acid as the diacids, and 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride as the catalyst. The furanyl polyamide was prepared according to the following steps:

[0053] S1. Under nitrogen protection, 0.75 mol of 2,5-furandicarboxylic acid and 0.25 mol of azelaic acid were added to DMAc (the mass ratio of the main system solvent to the diamine was 6:1). The mixture was stirred at 300 r / min at room temperature until a homogeneous suspension was formed, thus obtaining the main reaction solution.

[0054] S2. Under continuous nitrogen protection and stirring at 300 r / min, the main reaction solution was cooled to 10℃, and 1.20 mol DMT-MM was added for stirring and activation. 1.00 mol 1,3-propanediamine was dissolved in DMAc (solvent to diamine mass ratio of 2:1) to prepare a diamine solution, which was added dropwise to the reaction system, and the addition rate was controlled to maintain the system temperature at 10℃. After the addition was completed, the reaction was stirred at 300 r / min for 5 h. After the reaction was completed, the product was separated by washing with water, filtration, and vacuum drying to obtain furanyl polyamide.

[0055] The resulting furanyl polyamide has a tensile strength of 86 MPa, an elongation at break of 15.3%, and a thermal decomposition temperature (Td, 5%) of 358 °C with 5% mass loss.

[0056] Example 6

[0057] All chemical reagents used in this embodiment are commercially available. In this embodiment, 1,4-butanediamine is used as the diamine, acetonitrile is used as the organic solvent, 2,5-furandicarboxylic acid and dodecanoic acid are used as the diacids, and 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride is used as the catalyst. The furanyl polyamide is prepared according to the following steps:

[0058] S1. Under nitrogen protection, 0.20 mol of 2,5-furandicarboxylic acid and 0.80 mol of dodecanoic acid were added to acetonitrile (the mass ratio of the main system solvent to the diamine was 6:1), and heated to 40 °C with stirring at 250 r / min to assist dissolution and obtain the main reaction solution.

[0059] S2. Under continuous nitrogen protection and stirring at 250 r / min, the main reaction solution was cooled to 5℃, and 1.10 mol DMT-MM was added for stirring and activation. 0.99 mol 1,4-butanediamine was dissolved in acetonitrile (the mass ratio of solvent to diamine was 2:1) to prepare a diamine solution, which was added dropwise to the reaction system while controlling the addition rate to maintain the system temperature at 5℃. After the addition was completed, the reaction was stirred at 250 r / min for 4 h. After the reaction was completed, the product was separated by washing with water, centrifugation, secondary washing with water, ultrafiltration, and vacuum drying to obtain high-purity furanyl polyamide.

[0060] The resulting furanyl polyamide has a tensile strength of 73 MPa, an elongation at break of 19.2%, and a thermal decomposition temperature (Td, 5%) of 342 °C with 5% mass loss.

[0061] Example 7

[0062] All chemical reagents used in this embodiment are commercially available. In this embodiment, the diamine used is m-phenylenediamine, the organic solvent is DMAc, the diacids are 3-methylfuran-2,5-dicarboxylic acid and isophthalic acid, and the catalyst is 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride. The furanyl polyamide is prepared according to the following steps:

[0063] S1. Under nitrogen protection, 0.70 mol of 3-methylfuran-2,5-dicarboxylic acid and 0.30 mol of isophthalic acid were added to DMAc (the mass ratio of the main system solvent to the diamine was 6:1), and heated to 50 °C with stirring at 350 r / min to assist dissolution and obtain the main reaction solution.

[0064] Under continuous nitrogen protection and stirring at 350 r / min, the main reaction solution was cooled to 15℃, and 1.25 mol DMT-MM was added for stirring and activation. 1.00 mol m-phenylenediamine was dissolved in DMAc (solvent to diamine mass ratio of 2:1) to prepare a diamine solution, which was added dropwise to the reaction system, and the addition rate was controlled to maintain the system temperature at 15℃. After the addition was completed, the reaction was stirred at 350 r / min for 6 h. After the reaction was completed, the product was separated by washing with water, centrifugation, and vacuum drying to obtain high-purity furanyl polyamide.

[0065] The resulting furanyl polyamide has a tensile strength of 98 MPa, an elongation at break of 10.8%, and a thermal decomposition temperature (Td, 5%) of 376 °C with 5% mass loss.

Claims

1. A green process for the production of furan-based polyamides suitable for industrial production, characterized by, Including the following steps: S1. Obtaining the main reaction solution: Under inert gas protection, furan diacid monomer is added to an organic solvent and stirred at room temperature until a homogeneous suspension is formed, or heated to 40℃~60℃ to assist in dissolution and form a homogeneous suspension, thereby obtaining the main reaction solution; the furan diacid monomer is a furan-based core monomer or a mixture of comonomers composed of a furan-based core monomer and a second type of diacid; the organic solvent is at least one of N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), N-methylpyrrolidone (NMP), and acetonitrile; S2. Obtaining furanyl polyamide: Under continuous inert gas protection and stirring, the main reaction solution is cooled to 0℃~25℃, a catalyst is added, and the mixture is stirred to activate it. The catalyst is 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholine chloride (DMT-MM), and the molar ratio of the catalyst to the diacid monomer is (1.05:1)~(1.5:1). The diamine monomer is dissolved in the same organic solvent as the main reaction solution to prepare a diamine solution. The diamine monomer is selected from aromatic diamines or aliphatic diamines, and the mass ratio of the organic solvent to the diamine monomer in the diamine solution is (1:1)~(3:1). The diamine solution is added dropwise to the main reaction solution while maintaining the temperature at 0℃~25℃. After the addition is complete, the reaction continues under stirring. After the reaction is completed, the product is separated to obtain furanyl polyamide.

2. A process for the green preparation of furan-based polyamides suitable for industrial production according to claim 1, characterized in that, The core monomer of the furan is substituted or unsubstituted furan dicarboxylic acid; the substituent is a C1-C4 alkyl group.

3. A process for the green preparation of furan-based polyamides suitable for industrial production according to claim 2, characterized in that, The core monomer of the furan class is 2,5-furandicarboxylic acid.

4. The process for the green preparation of furan-based polyamides according to claim 1, characterized in that, In the copolymer monomer mixture, the molar ratio of the furan-based core monomer to the second diacid is 9:1 to 1:9, and the second diacid is one of terephthalic acid, isophthalic acid, adipic acid, azelaic acid, and dodecanoic acid.

5. A process for the green preparation of furan-based polyamides suitable for industrial production according to claim 4, characterized in that, In the copolymer monomer mixture, the molar ratio of the furan-type core monomer to the second diacid is 4:1 to 1:

4.

6. The method for green preparation of furan-based polyamide according to claim 1, wherein, The aromatic diamine is any one of 4,4'-diaminodiphenyl ether, p-phenylenediamine, m-phenylenediamine, and 4,4-diaminodiphenylmethane; the aliphatic diamine is any one of 1,6-hexanediamine, 1,3-propanediamine, and 1,4-butanediamine.

7. The method for green preparation of furan-based polyamide according to claim 1, wherein, The mass ratio of the organic solvent to the diamine monomer in the main reaction solution is (4:1) to (8:1).

8. The method for green preparation of furan-based polyamide according to claim 1, wherein, The molar ratio of furanolic acid monomer to diamine monomer is (1:0.98) to (1:1.02).

9. The green preparation method of furanyl polyamide suitable for industrial production as described in claim 1, characterized in that, The product separation process involves water washing, filtration / centrifugation, and drying.

10. The application of furanyl polyamide prepared by any of the green preparation methods suitable for industrial production of furanyl polyamide according to claims 1 to 10, characterized in that... It can be applied to any field of fiber, membrane materials, and nanoparticle / polymer composite materials.