Bio-based flame-retardant polyamide resin and preparation method thereof

Abstract

The invention relates to a bio-based flame-retardant polyamide resin and a preparation method thereof in the technical field of polyamide. The bio-based flame-retardant polyamide resin comprises the following components: 2-8 wt% of a component A, 89-95 wt% of a component B and 2-3 wt% of a component C, the component A is a reactive halogen-free flame retardant, serves as a flame-retardant component and participates in polyamide polymerization reaction, the component B is a bio-based polyamide PA5X saline solution and serves as a polymerized resin main body, and the component C is a combination of a polymerization catalyst, a stabilizer and an antioxidant and serves as an additive component. The bio-based flame-retardant polyamide resin with the performance reaching the standard is successfully prepared by using a one-pot method, the flame retardant DOPO-2COOH can be uniformly dispersed in a matrix by participating in a polymerization reaction, the flame retardant property of the material is remarkably improved, the flame retardant grade of the material can reach V-0 grade, meanwhile, no negative influence is generated on the polymerization reaction, and good mechanical properties are maintained.

Description

Technical Field

[0001] The present invention relates to the technical field of polyamides, and particularly relates to a bio-based flame-retardant polyamide resin and a preparation method thereof. Background Art

[0002] Polyamide (PA), as an important engineering plastic, has been extremely widely used in many fields such as automotive manufacturing, electronics and electrical appliances, textiles, aerospace, etc. due to its excellent mechanical properties, good wear resistance, chemical corrosion resistance, and easy processability. In the automotive field, polyamide is used to manufacture engine components, interior materials, and electrical equipment housings, etc.; in the electronics and electrical appliances industry, it is commonly used to produce various electrical appliance housings, connectors, circuit boards and other components; in the textile industry, it can be made into fibers for making high-performance industrial fabrics and clothing fabrics.

[0003] However, most traditional polyamide resins rely on fossil raw materials for preparation. With the increasing global resource tension and the continuous reduction of fossil resource reserves, this not only leads to large fluctuations in the production cost of polyamide, but also causes great pressure on the environment. In addition, the flame-retardant performance of ordinary polyamide is poor, and there are great potential safety hazards in many application scenarios, especially in the electronics and electrical appliances and construction fields with high fire safety requirements. Once a fire occurs, ordinary polyamide products are easy to burn and release a large amount of heat and toxic smoke, posing a serious threat to the lives and property safety of people.

[0004] In order to meet the requirements of sustainable development and the increasingly strict fire safety standards, the research and development of polyamide resins prepared from bio-based raw materials and having good flame-retardant performance has become an important research direction in the field of polyamides. Bio-based raw materials are widely sourced and renewable, which can effectively reduce the dependence on fossil resources and reduce carbon emissions, and have positive significance for environmental protection. At the same time, polyamide resins with excellent flame-retardant performance can significantly improve the safety of related products and broaden the application scope of polyamides. At present, although there have been some research reports on bio-based polyamides and flame-retardant polyamides, effectively combining the two to prepare bio-based flame-retardant polyamide resins with excellent comprehensive properties and developing an efficient and environmentally friendly preparation method are still the key problems to be solved in this field. Summary of the Invention

[0005] Aiming at the defects in the prior art, the purpose of the present invention is to provide a bio-based flame-retardant polyamide resin and a preparation method thereof.

[0006] According to the preparation method of a bio-based flame-retardant polyamide resin provided by the present invention, it includes the following steps: S1. Add 2 - 8 wt% of component A, 89 - 95 wt% of component B, and 2 - 3 wt% of component C into the batch polymerization kettle. After purging the air in the kettle with nitrogen, maintain the pressure at 2 - 8 bar under a nitrogen atmosphere. Component A is a reactive halogen - free flame retardant, which serves as a flame - retardant component and participates in the polyamide polymerization reaction. Component B is an aqueous solution of bio - based polyamide PA5X with a concentration of 40 - 70%, serving as the resin matrix after polymerization. Component C is a combination of a polymerization catalyst, a stabilizer, and an antioxidant, serving as an additive component. S2: Start the heating program of the batch polymerization kettle, raise the temperature of the solution to 170 - 230 °C, and raise the pressure to 17 - 20 bar. S3. Based on step S2, continue to raise the temperature to 250 - 290 °C, and perform exhaust and pressure maintenance for 1 - 3 h during the temperature - rising process, and keep stirring the solution during the exhaust and pressure - maintenance period. S4. After step S3, reduce the pressure to 0 - 0.3 bar, evacuate for 5 - 60 min, and then extrude the resin melt out of the polymerization kettle under a nitrogen pressure of 6 - 9 bar. After cooling and pelletizing, a bio - based flame - retardant polyamide resin is obtained.

[0007] In some embodiments, the reactive halogen - free flame retardant is a D0P0 derivative, and the D0P0 derivative is DOPO - 2COOH, and its structural formula is: .

[0008] Component A is a reactive halogen - free flame retardant (DOPO - 2COOH), which serves as a flame - retardant component and participates in the polyamide polymerization reaction. Its backbone structure is 9,10 - dihydro - 9 - oxa - 10 - phosphaphenanthrene - 10 - oxide (DOPO), which is modified by a dicarboxyl group and can participate in the polyamide polymerization reaction to ensure its stability and dispersion in the resin matrix. Due to the presence of the carboxylic acid structure, DOPO - 2COOH has higher thermal stability than DOPO, ensuring that it will not decompose during the polymerization process.

[0009] In some embodiments, the amine component in the aqueous solution of bio - based polyamide PA5X is bio - based pentamethylenediamine, and X is a dicarboxylic acid monomer. The dicarboxylic acid monomer is one or more combinations of bio - based sebacic acid, bio - based dodecanedioic acid, and bio - based long - chain dicarboxylic acid Pripol TM 1009, where the structural formula of bio - based long - chain dicarboxylic acid Pripol TM 1009 is: .

[0010] Biobased pentamethylenediamine is selected to replace traditional hexamethylenediamine. Pentamethylenediamine is prepared by biological fermentation of amylase in corn or straw, and is a green and environmentally friendly monomer; in terms of carboxylic acid, commercial biobased dicarboxylic acid monomers are selected to replace traditional adipic acid. Component B is an aqueous solution of biobased polyamide PA5X salt with a concentration of 40-70%, serving as the main body of the resin after polymerization.

[0011] In some embodiments, the molar ratio of the pentamethylenediamine to the dicarboxylic acid monomer is (0.90 to 1.20):1.

[0012] In some embodiments, the pH value of the aqueous solution of biobased polyamide PA5X salt is 7.3 to 8.9, and the pH value is measured at 20 °C in a 10 wt% concentration saline solution.

[0013] In some embodiments, the catalyst is one or a combination of hypophosphorous acid, hypophosphite, sulfonic acid, and sulfonate.

[0014] In some embodiments, the stabilizer is one or a combination of polycarbodiimide, S-EED, inorganic copper salt, and organic copper salt.

[0015] In some embodiments, the antioxidant is one or a combination of antioxidant 1010, antioxidant 1098, antioxidant 168, antioxidant 1076, and antioxidant DNP.

[0016] In some embodiments, the mass ratio of the catalyst, stabilizer, and antioxidant in Component C is (0.01 to 0.05):(0.85 to 1.15):1.

[0017] The present invention also provides a biobased flame-retardant polyamide resin, comprising the following components: 2-8 wt% of Component A, 89-95 wt% of Component B, and 2-3 wt% of Component C; Component A is a reactive halogen-free flame retardant, and the reactive halogen-free flame retardant is a D0P0 derivative. The D0P0 derivative is DOPO-2COOH, and its structural formula is:

[0018] Component B is an aqueous solution of biobased polyamide PA5X salt. The amine component in the aqueous solution of biobased polyamide PA5X salt is biobased pentamethylenediamine, X is a dicarboxylic acid monomer, and the dicarboxylic acid monomer is one or a combination of biobased sebacic acid, biobased dodecanedioic acid, and biobased long-chain dicarboxylic acid Pripol TM 1009, and the structural formula of biobased long-chain dicarboxylic acid Pripol TM 1009 is:

[0019] Component C is a combination of a polymerization catalyst, a stabilizer and an antioxidant. The mass ratio of the catalyst, the stabilizer and the antioxidant in Component C is (0.01 - 0.05):(0.85 - 1.15):1.

[0020] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention successfully prepares a bio-based flame-retardant polyamide resin with qualified performance by using a one-pot method. The flame retardant DOPO-2COOH can be uniformly dispersed in the matrix by participating in the polymerization reaction, and the flame retardant performance of the material is significantly improved. Its flame retardant grade can reach V-0 level, and at the same time, it does not have a negative impact on the polymerization reaction, maintaining good mechanical properties. The prepared resin has stable performance, reducing both the dependence on petroleum resources and the environmental impact. The preparation method is simple in operation and low in cost, and has great potential for large-scale industrial application.

[0021] 2. For the bio-based flame-retardant polyamide resin prepared by the present invention, in terms of resources and environment, using bio-based raw materials to prepare polyamide resin greatly reduces the dependence on petroleum resources, effectively alleviates the cost fluctuation problem caused by the shortage of petroleum resources, and at the same time reduces carbon emissions and negative environmental impacts during the production process, conforming to the concept of sustainable development and carbon neutrality, and contributing to environmental protection; in terms of material properties, the prepared polyamide resin has excellent mechanical properties, can meet various application scenarios with high requirements for material strength and durability, and its excellent flame retardant performance can effectively inhibit combustion during a fire, greatly reducing the fire spread speed, heat release and toxic smoke release amount, providing strong support for ensuring personnel safety and reducing property losses. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] By reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings, other features, objects and advantages of the present invention will become more apparent: Figure 1 It is a process flow chart of the preparation method of the bio-based flame-retardant polyamide resin of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several changes and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0024] The present invention provides a preparation method of a bio-based flame-retardant polyamide resin, and its process flow is as Figure 1As shown, it aims to achieve a green transformation in the production of polyamide resin through innovative raw material selection and preparation processes, reduce dependence on petroleum resources, fill the relevant technological gaps, and provide new solutions for the industry development. In the following examples, all chemical reagents are commercial reagents and can be purchased from the market.

[0025] Example 1: Add 196.0 kg of 53% concentration PA510 salt solution, 4.2 kg of DOPO-2COOH, 0.2 kg of sodium hypophosphite, 0.8 kg of antioxidant 1098, 0.3 kg of antioxidant 168, and 0.7 kg of S-EED stabilizer into the polymerization kettle. Replace the air in the polymerization kettle with nitrogen three times, fill the polymerization kettle with nitrogen, and keep the pressure at 4 bar. Start heating under a nitrogen atmosphere. The solution is heated to 210 °C, and the pressure rises to 19.5 bar. Exhaust and maintain pressure at this pressure and continue heating to 265 °C. Keep the pressure for 2 h, while maintaining stirring. Reduce the pressure to remove water vapor. Reduce the pressure to 0 bar (gauge pressure), evacuate for 60 min, then discharge the material. After cooling with cooling water and pelletizing, a bio-based flame-retardant polyamide resin is obtained.

[0026] Comparative Example 1: Add 196.0 kg of 53% concentration PA510 salt solution, 0.2 kg of sodium hypophosphite, 0.8 kg of antioxidant 1098, 0.3 kg of antioxidant 168, and 0.7 kg of S-EED stabilizer into the polymerization kettle. Replace the air in the polymerization kettle with nitrogen three times, fill the polymerization kettle with nitrogen, and keep the pressure at 4 bar. Start heating under a nitrogen atmosphere. The solution is heated to 210 °C, and the pressure rises to 19.5 bar. Exhaust and maintain pressure at this pressure and continue heating to 265 °C. Keep the pressure for 2 h, while maintaining stirring. Reduce the pressure to remove water vapor. Reduce the pressure to 0 bar (gauge pressure), evacuate for 60 min, then discharge the material. After cooling with cooling water and pelletizing, a bio-based polyamide resin is obtained.

[0027] Example 2: Add 196 kg of 42% concentration PA512 salt solution, 3.3 kg of DOPO-2COOH, 0.2 kg of sodium hypophosphite, 0.8 kg of antioxidant 1098, 0.3 kg of antioxidant 168, and 0.7 kg of S-EED stabilizer into the polymerization kettle. Replace the air in the polymerization kettle with nitrogen three times, fill the polymerization kettle with nitrogen, and keep the pressure at 4 bar. Start heating under a nitrogen atmosphere. The solution is heated to 210 °C, and the pressure rises to 19.5 bar. Exhaust and maintain pressure at this pressure and continue heating to 265 °C. Keep the pressure for 2 h, while maintaining stirring. Reduce the pressure to remove water vapor. Reduce the pressure to 0 bar (gauge pressure), evacuate for 50 min, then discharge the material. After cooling with cooling water and pelletizing, a bio-based flame-retardant polyamide resin is obtained.

[0028] Comparative Example 2: 196 kg of a 42% concentration PA512 salt solution, 0.2 kg of sodium hypophosphite, 0.8 kg of antioxidant 1098, 0.3 kg of antioxidant 168, and 0.7 kg of S-EED stabilizer were added to a polymerization kettle. The air in the polymerization kettle was replaced with nitrogen three times, and the polymerization kettle was filled with nitrogen, maintaining a pressure of 4 bar. Heating was started under a nitrogen atmosphere, and the solution was heated to 210 °C, and the pressure rose to 19.5 bar. Under this pressure, exhaust gas was discharged and the pressure was maintained, and the temperature was continued to be raised to 265 °C, and the pressure was maintained for 2 h. Stirring was maintained during this period, and the pressure was reduced to remove water vapor. The pressure was reduced to 0 bar (gauge pressure), and after vacuuming for 50 min, the product was discharged, cooled by cooling water, and pelletized to obtain a bio-based polyamide resin.

[0029] Example 3: 196.0 kg of a 33% concentration PA5P salt solution, 2.6 kg of DOPO-2COOH, 0.2 kg of sodium hypophosphite, 0.8 kg of antioxidant 1098, 0.3 kg of antioxidant 168, and 0.7 kg of S-EED stabilizer were added to a polymerization kettle. The air in the polymerization kettle was replaced with nitrogen three times, and the polymerization kettle was filled with nitrogen, maintaining a pressure of 4 bar. Heating was started under a nitrogen atmosphere, and the solution was heated to 210 °C, and the pressure rose to 19.5 bar. Under this pressure, exhaust gas was discharged and the pressure was maintained, and the temperature was continued to be raised to 265 °C, and the pressure was maintained for 2 h. Stirring was maintained during this period, and the pressure was reduced to remove water vapor. The pressure was reduced to 0 bar (gauge pressure), and after vacuuming for 40 min, the product was discharged, cooled by cooling water, and pelletized to obtain a bio-based flame-retardant polyamide resin.

[0030] Comparative Example 3: 196.0 kg of a 33% concentration PA5P salt solution, 0.2 kg of sodium hypophosphite, 0.8 kg of antioxidant 1098, 0.3 kg of antioxidant 168, and 0.7 kg of S-EED stabilizer were added to a polymerization kettle. The air in the polymerization kettle was replaced with nitrogen three times, and the polymerization kettle was filled with nitrogen, maintaining a pressure of 4 bar. Heating was started under a nitrogen atmosphere, and the solution was heated to 210 °C, and the pressure rose to 19.5 bar. Under this pressure, exhaust gas was discharged and the pressure was maintained, and the temperature was continued to be raised to 265 °C, and the pressure was maintained for 2 h. Stirring was maintained during this period, and the pressure was reduced to remove water vapor. The pressure was reduced to 0 bar (gauge pressure), and after vacuuming for 40 min, the product was discharged, cooled by cooling water, and pelletized to obtain a bio-based polyamide resin.

[0031] Example 4: 196.0 kg of 33% PA5P salt solution, 3.9 kg of DOPO-2COOH, 0.2 kg of sodium hypophosphite, 0.8 kg of antioxidant 1098, 0.3 kg of antioxidant 168, and 0.7 kg of S-EED stabilizer were added to the polymerization kettle. The air in the polymerization kettle was replaced with nitrogen three times, and then the kettle was filled with nitrogen, maintaining a pressure of 4 bar. Heating was started under a nitrogen atmosphere. The solution was heated to 210 °C, and the pressure rose to 19.5 bar. At this pressure, exhaust and pressure maintenance were carried out, and the temperature was further raised to 265 °C and maintained for 2 h. Stirring was maintained during this period, and the pressure was reduced to remove water vapor. The pressure was reduced to 0 bar (gauge pressure), and after vacuum pumping for 40 min, the product was discharged, cooled by cooling water, and pelletized to obtain the bio-based flame-retardant polyamide resin.

[0032] Example 5: 196.0 kg of 33% PA5P salt solution, 5.2 kg of DOPO-2COOH, 0.2 kg of sodium hypophosphite, 0.8 kg of antioxidant 1098, 0.3 kg of antioxidant 168, and 0.7 kg of S-EED stabilizer were added to the polymerization kettle. The air in the polymerization kettle was replaced with nitrogen three times, and then the kettle was filled with nitrogen, maintaining a pressure of 4 bar. Heating was started under a nitrogen atmosphere. The solution was heated to 210 °C, and the pressure rose to 19.5 bar. At this pressure, exhaust and pressure maintenance were carried out, and the temperature was further raised to 265 °C and maintained for 2 h. Stirring was maintained during this period, and the pressure was reduced to remove water vapor. The pressure was reduced to 0 bar (gauge pressure), and after vacuum pumping for 40 min, the product was discharged, cooled by cooling water, and pelletized to obtain the bio-based flame-retardant polyamide resin.

[0033] Example 6: 196.0 kg of 33% PA5P salt solution, 6.0 kg of DOPO-2COOH, 0.2 kg of sodium hypophosphite, 0.8 kg of antioxidant 1098, 0.3 kg of antioxidant 168, and 0.7 kg of S-EED stabilizer were added to the polymerization kettle. The air in the polymerization kettle was replaced with nitrogen three times, and then the kettle was filled with nitrogen, maintaining a pressure of 4 bar. Heating was started under a nitrogen atmosphere. The solution was heated to 210 °C, and the pressure rose to 19.5 bar. At this pressure, exhaust and pressure maintenance were carried out, and the temperature was further raised to 265 °C and maintained for 2 h. Stirring was maintained during this period, and the pressure was reduced to remove water vapor. The pressure was reduced to 0 bar (gauge pressure), and after vacuum pumping for 40 min, the product was discharged, cooled by cooling water, and pelletized to obtain the bio-based flame-retardant polyamide resin.

[0034] The test methods are as follows: The tensile strength and elongation at break of the specimen were tested according to standard GB / T 1040. The specimen was of type 5, with a thickness of 2 ± 0.2 mm, and the test rate was 50 mm / min.

[0035] The limiting oxygen index of the material was tested according to the ISO 4589-2 method. After placing the test strips (80*10*4 mm) at a temperature of 20±2 °C and a humidity of 65±1% for 80 h, different oxygen concentrations (%) were set. The test strips were ignited at this oxygen concentration, and the burning time and burning length of the test strips were recorded. The limiting oxygen index of the material was calculated based on the burning state of the test strips at different oxygen concentrations.

[0036] The flame retardancy of the material was tested according to the UL-94 standard. The specimen (125*13*0.8 mm in thickness) was vertically fixed and ignited with a flame of a specified power for 10 seconds and then removed. The burning time of the specimen and whether there was any burning material dripping to ignite the cotton below were recorded.

[0037] The test results are shown in Table 1 as follows: Table 1 Tensile strength (MPa) Elongation at break (%) Limiting oxygen index (%) Flame retardant grade Example 1 67.2 138.2% 32.6 V-0 Example 2 50.9 178.9% 33.1 V-0 Example 3 29.7 230.9% 32.2 V-0 Example 4 28.4 229.9% 33.9 V-0 Example 5 28.3 233.7% 35.7 V-0 Example 6 27.9 234.6% 35.9 V-0 Comparative example 1 66.8 142.9% 25.3 V-2 Comparative example 2 50.7 169.3% 24.3 V-2 Comparative example 3 28.2 228.9% 26.1 V-2 It can be seen from the comparison between Example 1 and Example 6 that the flame retardancy grades of the bio-based flame retardant polyamide resins prepared by the present invention can all reach V-0 level; it can be seen from the comparison between Example 3 and Example 6 that as the content of the flame retardant DOPO-2COOH in the resin matrix increases, the limiting oxygen index of the material increases. As the content further increases, the limiting oxygen index reaches a threshold value.

[0038] It can be seen from the comparison between the examples and the comparative examples that compared with the matrix resin without the addition of the flame retardant, the changes in the mechanical properties of the bio-based flame retardant polyamide resin prepared by the present invention are not significant, and all the mechanical property indexes can meet the actual use requirements. This fully shows that the flame retardant DOPO-2COOH can be uniformly dispersed in the matrix and will not have a negative impact on the polymerization reaction, thus maintaining good mechanical properties while ensuring the improvement of the flame retardancy of the material.

[0039] In summary, the present invention successfully prepares bio-based flame retardant polyamide resins with qualified properties by a one-pot method. The flame retardant DOPO-2COOH can be uniformly dispersed in the matrix by participating in the polymerization reaction. The flame retardancy of the material is significantly improved, and its flame retardancy grade can reach V-0 level. At the same time, it does not have a negative impact on the polymerization reaction and maintains good mechanical properties. The prepared resin has stable properties, reduces the dependence on petroleum resources and environmental impact, and the preparation method is simple in operation and low in cost, with great potential for large-scale industrial application.

[0040] The above embodiments are only used to illustrate the technical concept and characteristics of the present invention, and their purpose is to enable those who are familiar with this technology to understand the content of the present invention and implement it. It cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A preparation method of a bio-based flame-retardant polyamide resin, characterized in that, It includes the following steps: S1. Add 2-8 wt% of component A, 89-95 wt% of component B, and 2-3 wt% of component C into the batch polymerization kettle. After replacing the air in the kettle with nitrogen, maintain the pressure at 2-8 bar under a nitrogen atmosphere. Component A is a reactive halogen-free flame retardant, component B is an aqueous solution of bio-based polyamide PA5X salt, and component C is a combination of a polymerization catalyst, a stabilizer, and an antioxidant; S2. Start the heating program of the batch polymerization kettle, heat the solution to 170-230 °C, and raise the pressure to 17-20 bar; S3. On the basis of step S2, continue to heat up to 250-290 °C, and exhaust and maintain pressure for 1-3 h during the heating process, and keep stirring the solution during the exhaust and pressure maintenance period; S4. After step S3, reduce the pressure to 0-0.3 bar, evacuate for 5-60 min, and then extrude the resin melt out of the polymerization kettle under a nitrogen pressure of 6-9 bar. After cooling and pelletizing, a bio-based flame-retardant polyamide resin is obtained.

2. The preparation method of the bio-based flame-retardant polyamide resin according to claim 1, wherein The reactive halogen-free flame retardant is a D0P0 derivative, and the D0P0 derivative is DOPO-2COOH, and its structural formula is: 。 3. The preparation method of the bio-based flame-retardant polyamide resin according to claim 2, characterized in that, In the aqueous solution of the bio-based polyamide PA5X, the amine component is bio-based pentamethylenediamine, X is a dicarboxylic acid monomer, and the dicarboxylic acid monomer is bio-based sebacic acid, bio-based dodecanedioic acid, bio-based long-chain dicarboxylic acid Pripol TM one or a combination of more than one of 1009, wherein the bio-based long-chain dicarboxylic acid Pripol TM The structural formula of 1009 is: 。 4. The preparation method of the bio-based flame-retardant polyamide resin according to claim 3, wherein, The molar ratio of the pentamethylenediamine to the dicarboxylic acid monomer is (0.90-1.20):

1.

5. The preparation method of the bio-based flame-retardant polyamide resin according to claim 1, characterized in that, The pH value of the aqueous solution of bio-based polyamide PA5X salt is 7.3-8.9, and the pH value is measured at 20 °C for a 10 wt% concentration aqueous salt solution.

6. The preparation method of the bio-based flame-retardant polyamide resin according to claim 1, characterized in that, The catalyst is one or a combination of hypophosphorous acid, hypophosphite, sulfonic acid, and sulfonate.

7. The preparation method of the bio-based flame-retardant polyamide resin according to claim 6, characterized in that, The stabilizer is one or a combination of polycarbodiimide, S-EED, inorganic copper salt, and organic copper salt.

8. The preparation method of the bio-based flame-retardant polyamide resin according to claim 7, characterized in that, The antioxidant is one or a combination of antioxidant 1010, antioxidant 1098, antioxidant 168, antioxidant 1076, and antioxidant DNP.

9. The preparation method of the bio-based flame-retardant polyamide resin according to claim 8, characterized in that, The mass ratio of the catalyst, stabilizer, and antioxidant in component C is (0.01-0.05):(0.85-1.15):

1.

10. A bio-based flame-retardant polyamide resin, characterized in that, It includes the following components: 2-8 wt% of component A, 89-95 wt% of component B, and 2-3 wt% of component C; Component A is a reactive halogen-free flame retardant, the reactive halogen-free flame retardant is a D0P0 derivative, and the D0P0 derivative is DOPO-2COOH, and its structural formula is: ； The component B is an aqueous solution of bio-based polyamide PA5X. In the aqueous solution of bio-based polyamide PA5X, the amine component is bio-based pentamethylenediamine, X is a dicarboxylic acid monomer, and the dicarboxylic acid monomer is bio-based sebacic acid, bio-based dodecanedioic acid, and bio-based long-chain dicarboxylic acid Pripol TM One or a combination of more than one of 1009, wherein the bio-based long-chain dicarboxylic acid Pripol TM The structural formula of 1009 is: ； Component C is a combination of a polymerization catalyst, a stabilizer, and an antioxidant, and the mass ratio of the catalyst, stabilizer, and antioxidant in component C is (0.01-0.05):(0.85-1.15):1.

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