Long fiber reinforced halogen-free flame retardant bio-based polyamide composites and methods of making the same

Abstract

The application provides a long-fiber reinforced halogen-free flame-retardant bio-based polyamide composite material and a preparation method thereof. The bio-based polyamide is used as a resin matrix to connect continuous long fibers to each other, and other additives such as a halogen-free flame retardant are added, the raw material formula and the preparation process are improved on the basis of the traditional LFT process, and the long-fiber reinforced halogen-free flame-retardant bio-based polyamide composite material with excellent mechanical properties, halogen-free environmental protection, reliable performance and practicality is prepared.

Description

TECHNICAL FIELD

[0001] The present application relates to a long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material and a preparation method thereof. BACKGROUND

[0002] Polyamide has excellent properties such as strong wear resistance, impact resistance, fatigue resistance, corrosion resistance, oil resistance, etc. Glass fiber reinforced polyamide products have excellent comprehensive performance and are widely used in electronic and electrical, automotive, mechanical equipment and precision instrument fields. With the improvement of environmental awareness of the whole society, traditional halogen and bromine flame retardants cannot meet the current environmental protection requirements, and halogen-free flame retardant has become the development trend of glass fiber reinforced flame-retardant polyamide technology. However, in order to achieve V-0 level, ordinary glass fiber reinforced polyamide needs to add a lot of halogen-free flame retardants, which will seriously reduce the mechanical properties of the material, especially the impact performance.

[0003] Long fiber reinforced resin composite material is a kind of reinforced resin with unidirectional arrangement of reinforcing fibers and fiber length comparable to resin pellet length. Compared with conventional short fiber reinforced resin, it has more excellent mechanical properties, especially the impact resistance of the material is extremely excellent. Although the use of continuous long glass fiber reinforced polyamide helps to improve the mechanical properties of the material, in order to ensure the infiltration effect of polyamide resin on continuous long glass fiber, the related long fiber reinforced thermoplastic (LFT for short) molding process usually needs to set very high process temperature (for example, 330-380℃), which inevitably leads to serious decomposition of halogen-free flame retardant. The current solution includes using flame-retardant masterbatch by blending flame-retardant masterbatch with long glass fiber reinforced masterbatch, but the content of flame retardant in the flame-retardant masterbatch is low, and the amount of masterbatch required is increased, resulting in a decrease in fiber content and the mechanical properties of the composite material cannot be effectively improved. There is also a high and low temperature double impregnation tank, which first impregnates non-flame-retardant resin at high temperature, and then impregnates flame-retardant resin at low temperature. However, due to the infiltration of non-flame-retardant resin first and then the infiltration of flame-retardant resin, the content of flame retardant is low, the flame-retardant effect is poor, and the process is complex, and the product quality cannot be guaranteed. SUMMARY

[0004] In order to overcome the deficiencies in the prior art, the present application provides a long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material and a preparation method thereof. The composite material enhances the mechanical properties of bio-based polyamide by using continuous long glass fiber, solves the problem of high temperature decomposition of halogen-free flame retardant in the infiltration process, poor flame-retardant effect and inability to improve mechanical properties, and the preparation process is simple, can be produced at high speed and continuously, has high efficiency and guaranteed quality.

[0005] In the present application, the content percentage is the weight percentage if not otherwise specified.

[0006] The present application solves the above technical problems by the following technical solutions:

[0007] A long-fiber reinforced halogen-free flame-retardant bio-based polyamide composite material, comprising the following components by weight percentage:

[0008] Bio-based polyamide resin 10-80wt%;

[0009] Continuous long fiber 15-60wt%;

[0010] Halogen-free flame retardant 5-20wt%;

[0011] Other additives 0.1-25wt%;

[0012] Among them, the bio-based polyamide resin contains the following structural units (I), (II) and (III)

[0013]

[0014] The molar ratio of the structural unit (I) to the structural unit (II) is 1:(0.1-0.9);

[0015] The molar ratio of the structural unit (I) to the structural unit (III) is 1:(0.1-0.9).

[0016] The structural units (I), (II) and (III) are connected by amide bonds.

[0017] In some specific embodiments, the molar ratio of the structural unit (II) to the structural unit (III) is 1:(0.1-1.5), for example, it can be 1:(0.35-0.55), for example, 1:0.45; 1:0.55-0.85, for example, 1:0.72; or 1:0.85-1.2, for example, 1:1.05.

[0018] In some specific embodiments, the relative viscosity of the bio-based polyamide resin is 2.0-3.2. The relative viscosity is determined by the Ubbelohde viscometer concentrated sulfuric acid (concentration 96%) method.

[0019] In some specific embodiments, the number average molecular weight of the bio-based polyamide resin is 20-70 thousand, further 30-60 thousand.

[0020] In some specific embodiments, the water content of the bio-based polyamide resin is 500-2000 ppm. The water content can be reduced by drying.

[0021] In some specific embodiments, the melting point of the bio-based polyamide resin is 260-330℃, further 270-300℃.

[0022] In some specific embodiments, the bio-based polyamide resin is formed from pentanediamine and dicarboxylic acid, wherein the molar ratio of the pentanediamine and the dicarboxylic acid is (1-1.05):1, for example 1.05:1.

[0023] In some specific embodiments, the method for preparing the bio-based polyamide resin comprises the following steps: preparing a polyamide salt solution from pentanediamine, dicarboxylic acid and water, and heating the polyamide salt solution to polymerize and obtain the bio-based polyamide resin.

[0024] In some specific embodiments, the dicarboxylic acid contains 40-90 mol% of adipic acid and 10-60 mol% of terephthalic acid or a derivative of terephthalic acid, and the percentages are mole percentages.

[0025] In some specific embodiments, the method for preparing the bio-based polyamide resin comprises the following steps: (1) mixing water, pentanediamine, terephthalic acid or a derivative of terephthalic acid, and adipic acid to prepare a polyamide salt aqueous solution with a concentration of 30-75 wt% under a nitrogen or inert gas atmosphere; (2) transferring the polyamide salt aqueous solution to a polymerization device (for example, a polymerization kettle), heating under a nitrogen or inert gas atmosphere, raising the temperature in the reaction system to 230-310℃, and raising the pressure to 0.7-2.5 MPa, and maintaining for 60-180 minutes; then, in 30-120 minutes, venting to reduce the pressure to normal pressure while raising the temperature to 260-340℃; vacuumizing to reduce the pressure to -(0.02-0.08) MPa, and maintaining for 30-120 minutes to obtain a melt; (3) drawing the melt and cutting into particles to obtain the bio-based polyamide resin PA56 / 5T.

[0026] In some specific embodiments, the content of the bio-based polyamide resin in the long-fiber-reinforced halogen-free flame-retardant bio-based polyamide composite material is 20-60 wt%.

[0027] In some specific embodiments, the continuous long fibers include one or a combination of glass fibers, carbon fibers, aramid fibers, metal fibers, boron fibers, and basalt fibers. For example, continuous long glass fibers or continuous long carbon fibers.

[0028] In some specific embodiments, the continuous long fibers are continuous long glass fibers, the monofilament diameter can be 5-50 μm, and preferably 10-20 μm; and / or, the linear density is 1000-3600 Tex.

[0029] In some embodiments, the continuous long fibers are continuous long carbon fibers; preferably, the continuous long carbon fibers are polyacrylonitrile-based carbon fibers; and / or, the number of filaments of the continuous long carbon fibers is 20,000-30,000, preferably 12,000 (12K), 24,000 (24K); and / or, the diameter of the filaments is 5-10 μm.

[0030] In some embodiments, the content of the continuous long fibers in the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite is 30-60 wt%.

[0031] In some embodiments, the halogen-free flame retardant includes any one or a combination of nitrogen-based organic flame retardant, phosphorus-based organic flame retardant, and inorganic flame retardant. For example, aluminum diethylphosphinate, melamine cyanurate, aluminum hydroxide, magnesium hydroxide, or zinc borate.

[0032] In some embodiments, the content of the halogen-free flame retardant in the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite is 10-15 wt%.

[0033] In some embodiments, the other additives include a compatibilizer, a toughener, a flow modifier, a lubricant, an antioxidant, a coupling agent, a surfactant, an antistatic agent, an ultraviolet light resistant agent, a thermal stabilizer, a plasticizer, or a nucleating agent, etc.

[0034] In some embodiments, the other additives include 5-10 wt% of a toughener, 1-5 wt% of a flow modifier, 0.1-5 wt% of a lubricant, and 0.1-5 wt% of an antioxidant.

[0035] In some embodiments, the other additives include 5-8 wt% of a toughener, 1-2 wt% of a flow modifier, 0.3-0.6 wt% of a lubricant, and 0.3-2 wt% of an antioxidant.

[0036] In some embodiments, the toughener is a polar monomer grafted polymer, wherein the polymer is at least one of polyethylene, polypropylene, ethylene-alpha-ethylene-octene copolymer, a copolymer of styrene and butadiene, polyethylene-polyphenylethylene-polypropylene terpolymer, ethylene-propylene-butadiene terpolymer, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer, and ethylene-acrylate-glycidyl methacrylate copolymer; and the polar monomer is a double bond polymerizable anhydride monomer, which is at least one of maleic anhydride, fumaric acid, itaconic acid, citraconic acid, citraconic anhydride, and vinyl succinic anhydride. Further, the toughener is PP-g-MAH, POE-g-MAH, POE-g-GMA, or EPDM-g-MAH.

[0037] In some embodiments, the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite has a toughening agent content of 5-8 wt%.

[0038] In some embodiments, the flow modifier comprises at least one of silicone polymer, ester resin, long carbon chain diacid, etc. For example, hyperbranched polyester or long carbon chain diacid. The long carbon chain diacid comprises undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, hexadecanedioic acid, heptadecanedioic acid, or octadecanedioic acid, further preferably dodecanedioic acid or tridecanedioic acid.

[0039] In some embodiments, the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite has a flow modifier content of 1-1.5 wt%.

[0040] In some embodiments, the lubricant comprises one or a combination of stearate lubricant, fatty amide lubricant, silicone powder or silicone granule, PE wax, ethylene-acrylic acid copolymer. Further preferably, the combination of fatty amide lubricant and PE wax, for example, the combination of EBS (ethylene bis-stearamide) and PE wax (polyethylene wax) at a mass ratio of 1:0.8-1.5, the combination of calcium stearate and PE wax at a mass ratio of 1:0.8-1.5.

[0041] In some embodiments, the lubricant is the combination of EBS and PE wax at a mass ratio of 1:1, the combination of calcium stearate and PE wax at a mass ratio of 1:1.

[0042] In some embodiments, the PE wax has a molecular weight of 500-5000, preferably 800-1500, for example 1000.

[0043] In some embodiments, the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite has a lubricant content of 0.4-1 wt%.

[0044] In some embodiments, the antioxidant comprises one or a combination of hindered phenolic antioxidant, phosphite antioxidant, amine antioxidant, thioester antioxidant. Further preferably, the combination of hindered amine antioxidant and phosphite antioxidant. The hindered phenolic antioxidant can be conventional in the art, for example, antioxidant 1010, antioxidant 1098. The phosphite antioxidant can be conventional in the art, for example, antioxidant 168, antioxidant 608.

[0045] In some embodiments, the antioxidant is the combination of antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1.

[0046] In some embodiments, the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite has an antioxidant content of 0.5-0.7wt%.

[0047] In some embodiments, the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite has a long particle shape, the long particle has a length of 3-30mm, for example, 12mm, and contains continuous long fibers, the continuous long fibers have a length of 3-30mm, for example, 12mm.

[0048] In some embodiments, the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite contains continuous long glass fibers, the continuous long glass fibers have a tensile strength of 150-300MPa, a bending strength of 230-350MPa, a bending modulus of 7-15GPa, a notched impact strength of 10-30KJ / m 2 , an limiting oxygen index of 25-34%, and an appearance grade of 4 or more.

[0049] In some embodiments, the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite contains continuous long carbon fibers, the continuous long carbon fibers have a tensile strength of 270-400MPa, a bending strength of 350-500MPa, a bending modulus of 15-30GPa, a notched impact strength of 10-30KJ / m 2 , an limiting oxygen index of 25-34%, and an appearance grade of 4 or more.

[0050] The application also provides a preparation method of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite, which comprises the following steps:

[0051] S1, mixing raw material components of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite and then melt extruding to obtain a melt, and controlling the temperature to be 220-320℃;

[0052] S2, conveying the melt obtained in S1 to an impregnation die, controlling the temperature of the impregnation die to be 265-320℃, pulling the continuous long fibers into the impregnation die, and impregnating the melt and the continuous long fibers, and then cooling and cutting to obtain long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles;

[0053] In the application, the content of the continuous long fibers is controlled to be 15-60wt%, and further controlled to be 30-50wt%.

[0054] In some embodiments, in step S1, the mixing is stirring mixing, and the stirring mixing device can be a high-speed stirrer.

[0055] In some embodiments, in step S1, the melt extrusion can be performed by using a twin-screw extruder or a single-screw extruder, preferably a twin-screw extruder. In some embodiments, the length-diameter ratio of the twin-screw extruder is (20-50): 1, further (20-40): 1, preferably 36: 1.

[0056] In some embodiments, in step S1, when a twin-screw extruder is used, the twin-screw extruder is operated in a five-zone heating mode, preferably, the temperature of the first zone is 220-280°C, the temperature of the second zone is 240-290°C, the temperature of the third zone is 260-300°C, the temperature of the fourth zone is 260-300°C, the temperature of the fifth zone is 270-330°C, and the temperature of the die head is 270-330°C. For example, the temperature of the first zone to the fifth zone to the die head is 230°C, 250°C, 270°C, 280°C, 300°C, 310°C, respectively.

[0057] In some embodiments, in step S1, the speed of the screw extrusion is 200-600 rpm / min, for example, 300 rpm / min.

[0058] In some embodiments, the content of the continuous long fibers can be controlled by adjusting the aperture of the hole template, the speed of the screw extrusion, and the speed of the traction.

[0059] In some embodiments, in step S1, after the extrusion, a filtration step is preferably further included. The filtration can be performed by using a melt filter.

[0060] In some embodiments, in step S2, the impregnation die head can be a die head commonly used in the art. The width of the impregnation die head is preferably 100-650 mm, for example, 300 mm.

[0061] In some embodiments, the temperature of the impregnation die head is 260-325°C. Preferably, when a twin-screw extruder is used, the temperature of the impregnation die head is within the range of 0-15°C of the eighth zone temperature of the twin-screw extruder.

[0062] In some embodiments, in step S2, the speed of the traction is controlled to be 5-50 m / min, for example, 25 m / min.

[0063] In some embodiments, in step S2, the hole template is two rows, the aperture of the hole template is 3-10 mm, and the aperture of the second row of the hole template is 1-3 mm larger than that of the first row of the hole template, for example, the aperture of the first row of the hole template is 4 mm, and the aperture of the second row of the hole template is 6 mm.

[0064] In some specific embodiments, in step S2, the processing temperature of the hole template is 260-325℃, for example 300℃.

[0065] In some specific embodiments, in step S2, the cooling uses water cooling, and the water temperature is controlled to be 10-40℃.

[0066] In some specific embodiments, in step S2, the granulation can use a granulator commonly used in the art.

[0067] In some specific embodiments, the long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles have a length of 3-30mm, for example 12mm.

[0068] In some specific embodiments, the fibers in the long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles are continuous, and the length of the long fibers is comparable to the length of the long particles.

[0069] The application also provides a use of the aforementioned long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material in plastic products. Preferably, the plastic products include plastic products in automobile parts, and the composite material can be widely used in the fields of aerospace, military, automobile materials, sports equipment, building materials, or electronics.

[0070] On the basis of common sense in the art, the above-mentioned preferred conditions can be combined arbitrarily, i.e. to obtain each preferred example of the application. The reagents and raw materials used in the application are commercially available.

[0071] The positive progress effect of the application is that the application makes full use of the performance characteristics of bio-based polyamide, and the bio-based polyamide as a resin matrix connects continuous long fibers with each other, and by adding halogen-free flame retardants and other additives, the raw material formula and preparation process are improved on the basis of the traditional LFT process, and a long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material with excellent mechanical properties, halogen-free environmental protection, reliable performance, and practicality is prepared. BRIEF DESCRIPTION OF DRAWINGS

[0072] Figure 1 is a photo of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite long particles prepared in Example 1. DETAILED DESCRIPTION

[0073] The application will be further described by way of examples below, but the application is not limited in the scope of the examples. The experimental methods in the following examples are not specified, and the methods are selected according to conventional methods and conditions, or according to the instructions of the goods.

[0074] The raw materials in the following examples and comparative examples are all commercially available unless otherwise specified: PA6 (relative viscosity 2.46, end amino group content 54 mmol / kg, melting point 223℃, not containing bio-based) is purchased from Guangzhou Xinhui Meida Nylon Co., Ltd.; continuous long glass fiber is purchased from Owens Corning (OC), and the linear density is 1200 Tex; continuous long carbon fiber is purchased from Toray Group T700, and the number of monofilaments is 24K; dodecanedioic acid and tridecanedioic acid are purchased from Kaisai (Jinxian) Biomaterials Co., Ltd.; antioxidant is purchased from BASF Group in Germany; lubricants EBS and PE wax (molecular weight 1000) are purchased from Clariant in Germany; halogen-free flame retardant aluminum diethyl phosphinate is purchased from Clariant in Germany; toughening agent is purchased from Shanghai Jiaiyi Polymer Co., Ltd.

[0075] Bio-based polyamide A: the preparation method comprises the following steps: (1) mixing water, pentanediamine and dicarboxylic acid (molar ratio of adipic acid and terephthalic acid is 1:0.45) to prepare a polyamide salt aqueous solution with a concentration of 65wt% under a nitrogen atmosphere; the molar ratio of the pentanediamine and the dicarboxylic acid is 1.05:1; (2) transferring the polyamide salt aqueous solution to a polymerization kettle, heating under a nitrogen atmosphere, raising the temperature in the kettle to 290℃, raising the pressure in the polymerization device to 1.6 MPa, and maintaining for 110 minutes; then, in 85 minutes, venting to reduce the pressure to normal pressure while raising the temperature in the polymerization device to 300℃; vacuumizing to reduce the pressure to -0.05 MPa, and maintaining for 60 minutes to obtain a melt, which is drawn and cut into particles to obtain bio-based polyamide resin PA56 / 5T-A (relative viscosity 2.45, number average molecular weight 60,000, melting point 270℃, water content after drying 800 ppm).

[0076] Bio-based copolyamide B: the preparation method comprises the following steps: (1) mixing water, pentanediamine and dicarboxylic acid (molar ratio of adipic acid and terephthalic acid is 1:0.72) to prepare a polyamide salt aqueous solution with a concentration of 65wt% under a nitrogen atmosphere; the molar ratio of the pentanediamine and the dicarboxylic acid is 1.05:1; (2) transferring the polyamide salt aqueous solution to a polymerization kettle, heating under a nitrogen atmosphere, raising the temperature in the kettle to 290℃, raising the pressure in the polymerization device to 1.6 MPa, and maintaining for 110 minutes; then, in 85 minutes, venting to reduce the pressure to normal pressure while raising the temperature in the polymerization device to 300℃; vacuumizing to reduce the pressure to -0.05 MPa, and maintaining for 60 minutes to obtain a melt, which is drawn and cut into particles to obtain bio-based polyamide resin PA56 / 5T-B (relative viscosity 2.31, number average molecular weight 40,000, melting point 290℃, water content after drying 800 ppm).

[0077] Bio-based copolyamide C: the preparation method comprises the following steps: (1) mixing water, pentanediamine and dicarboxylic acid (molar ratio of 1:1.05 of adipic acid and terephthalic acid) under a nitrogen atmosphere to prepare a polyamide salt aqueous solution with a concentration of 65 wt%; the molar ratio of the pentanediamine and the dicarboxylic acid is 1.05:1; (2) transferring the polyamide salt aqueous solution to a polymerization kettle, heating under a nitrogen atmosphere, raising the temperature in the kettle to 290℃, raising the pressure in the polymerization device to 1.6 MPa, and maintaining for 110 minutes; then, in 85 minutes, the pressure is reduced to normal pressure while raising the temperature in the polymerization device to 300℃; vacuumizing to reduce the pressure to -0.05 MPa, and maintaining for 60 minutes to obtain a melt, which is drawn and granulated to obtain a bio-based polyamide resin PA56 / 5T-C (relative viscosity 2.24, number average molecular weight 30,000, melting point 300℃, and water content after drying 800 ppm).

[0078] Example 1

[0079] 1. The raw materials of each component of the long-fiber reinforced halogen-free flame-retardant bio-based polyamide composite material include: 42 wt% of bio-based polyamide resin PA56 / 5T-C, 40 wt% of continuous long glass fiber (1200 Tex), 10 wt% of halogen-free flame retardant aluminum diethyl phosphinate, 6 wt% of toughening agent POE-g-MAH, 1 wt% of flow modifier dodecanedioic acid, 0.4 wt% of lubricant (compound of EBS and PE wax with a mass ratio of 1:1), and 0.6 wt% of antioxidant (compound of antioxidant 1098 and antioxidant 608 with a mass ratio of 1:1).

[0080] 2. The preparation method of the long-fiber reinforced halogen-free flame-retardant bio-based polyamide composite material:

[0081] S1. After the raw materials of each component (except for the continuous long glass fiber) are stirred and mixed, they are fed into the main hopper of a twin-screw extruder, and then melt-extruded by the twin-screw extruder; wherein the length-diameter ratio of the screw of the twin-screw extruder is 36:1, the processing temperature from zone 1 to zone 5 to the die head is 230℃, 250℃, 270℃, 280℃, 300℃, 310℃ in turn, and the screw extrusion speed is 300 r / min.

[0082] S2, the melt obtained in S1 is transported to an impregnation die through the extruder die orifice, the width of the impregnation die is 300 mm, the temperature of the impregnation die is controlled at 315 ℃, the continuous long glass fiber is then pulled into the impregnation die at a pulling speed of 25 m / min, impregnation occurs by pulling the melt and the continuous long fiber, and the composite material is discharged from the die plate (the first die plate has a hole diameter of 4 mm, and the second die plate has a hole diameter of 6 mm) and then cooled, the processing temperature of the die plate is 300 ℃, the content of the continuous long glass fiber in the composite material is controlled at 40 wt% during the process, the temperature of the circulating water in the water cooler is set to 23 ℃ during the cooling process, and the long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm are obtained by the granulator, which contain continuous long fibers with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0083] Example 2

[0084] 1, the raw materials of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material include: 35 wt% of bio-based polyamide resin PA56 / 5T-C, 40 wt% of continuous long glass fiber (1200 Tex), 15 wt% of halogen-free flame retardant diethyl aluminum phosphinate, 7 wt% of toughening agent POE-g-MAH, 1.5 wt% of flow modifier dodecanedioic acid, 0.9 wt% of lubricant (compounded by EBS and PE wax at a mass ratio of 1:1), and 0.6 wt% of antioxidant (compounded by antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0085] 2, the preparation method of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material is the same as that in Example 1. The long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm are obtained, which contain continuous long fibers with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0086] Example 3

[0087] 1, the raw materials of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material include: 29 wt% of bio-based polyamide resin PA56 / 5T-C, 40 wt% of continuous long glass fiber (1200 Tex), 20 wt% of halogen-free flame retardant diethyl aluminum phosphinate, 8 wt% of toughening agent POE-g-MAH, 1.5 wt% of flow modifier dodecanedioic acid, 0.9 wt% of lubricant (compounded by EBS and PE wax at a mass ratio of 1:1), and 0.6 wt% of antioxidant (compounded by antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0088] 2. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material was prepared in the same way as example 1. Long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm were obtained, which contained continuous long fibers inside the long particles with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0089] Example 4

[0090] 1. The raw materials of each component of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material included: 42 wt% bio-based polyamide resin PA56 / 5T-C, 40 wt% continuous long glass fiber (1200 Tex), 10 wt% halogen-free flame retardant melamine cyanurate, 6 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (compounded by EBS and PE wax at a mass ratio of 1:1), 0.6 wt% antioxidant (compounded by antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0091] 2. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material was prepared in the same way as example 1. Long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm were obtained, which contained continuous long fibers inside the long particles with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0092] Example 5

[0093] 1. The raw materials of each component of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material included: 42 wt% bio-based polyamide resin PA56 / 5T-C, 40 wt% continuous long glass fiber (1200 Tex), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 6 wt% toughening agent POE-g-MAH, 1 wt% flow modifier tridecanedioic acid, 0.4 wt% lubricant (compounded by EBS and PE wax at a mass ratio of 1:1), 0.6 wt% antioxidant (compounded by antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0094] 2. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material was prepared in the same way as example 1. Long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm were obtained, which contained continuous long fibers inside the long particles with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0095] Example 6

[0096] 1. The raw materials of long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material include: 53 wt% bio-based polyamide resin PA56 / 5T-C, 30 wt% continuous long glass fiber (1200 Tex), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 5 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (compounded by EBS and PE wax at a mass ratio of 1:1), 0.6 wt% antioxidant (compounded by antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0097] 2. The preparation method of long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material is the same as that of example 1. Long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm are obtained, which contain continuous long fibers with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0098] Example 7

[0099] 1. The raw materials of long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material include: 21 wt% bio-based polyamide resin PA56 / 5T-C, 60 wt% continuous long glass fiber (1200 Tex), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 7 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (compounded by EBS and PE wax at a mass ratio of 1:1), 0.6 wt% antioxidant (compounded by antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0100] 2. The preparation method of long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material is the same as that of example 1. Long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm are obtained, which contain continuous long fibers with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0101] Example 8

[0102] 1. The raw materials of long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material include: 42 wt% bio-based polyamide resin PA56 / 5T-C, 40 wt% continuous long carbon fiber (24K), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 6 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (compounded by EBS and PE wax at a mass ratio of 1:1), 0.6 wt% antioxidant (compounded by antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0103] 2. The preparation method of long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material:

[0104] S1, the raw materials of each component (except continuous long carbon fiber) are stirred and mixed, then placed in the main feeding hopper of the twin-screw extruder, and then melted and extruded through the twin-screw extruder; wherein the length-diameter ratio of the screw of the twin-screw extruder is 36:1, and the processing temperature from zone 1 to zone 5 to the head is 230°C, 250°C, 270°C, 280°C, 300°C, 310°C, respectively, and the screw extrusion speed is 300r / min.

[0105] S2, the melt obtained in S1 is transported to the impregnation die through the extruder die, the width of the impregnation die is 300mm, the temperature of the impregnation die is controlled at 315°C, and the continuous long carbon fiber is pulled into the impregnation die at a pulling speed of 15m / min, the impregnation occurs by pulling the melt and the continuous long fiber, and then the composite material is cooled after being guided out of the die plate (the first die plate has a hole diameter of 4mm, and the second die plate has a hole diameter of 6mm), the processing temperature of the die plate is 300°C, the content of the continuous long fiber in the composite material is controlled at 40wt% during the process, the temperature of the circulating water in the water cooler is set to 23°C during cooling, and the long fiber reinforced halogen-free flame-retardant biobased polyamide long particles with a length of 12mm are obtained by the granulator, which contain continuous long fibers with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0106] Example 9

[0107] 1. The raw materials of the long fiber reinforced halogen-free flame-retardant biobased polyamide composite material include: 53wt% biobased polyamide resin PA56 / 5T-C, 30wt% continuous long carbon fiber (24K), 10wt% halogen-free flame retardant diethyl aluminum phosphinate, 5wt% toughening agent POE-g-MAH, 1wt% flow modifier dodecanedioic acid, 0.4wt% lubricant (compound of EBS and PE wax at a mass ratio of 1:1), and 0.6wt% antioxidant (compound of antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0108] 2. The preparation method of the long fiber reinforced halogen-free flame-retardant biobased polyamide composite material is the same as that of Example 8. The long fiber reinforced halogen-free flame-retardant biobased polyamide long particles with a length of 12mm are obtained, which contain continuous long fibers with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0109] Example 10

[0110] 1. The raw materials of each component of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material include: 21 wt% bio-based polyamide resin PA56 / 5T-C, 60 wt% continuous long carbon fiber (24K), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 7 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (compounded by EBS and PE wax at a mass ratio of 1:1), 0.6 wt% antioxidant (compounded by antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0111] 2. The preparation method of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material is the same as that of Example 8. Long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm are obtained, which contain continuous long fibers with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0112] Example 11

[0113] 1. The raw materials of each component of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material include: 42 wt% bio-based polyamide resin PA56 / 5T-A, 40 wt% continuous long glass fiber (1200 Tex), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 6 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (compounded by EBS and PE wax at a mass ratio of 1:1), 0.6 wt% antioxidant (compounded by antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0114] 2. The preparation method of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material is the same as that of Example 1. Long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm are obtained, which contain continuous long fibers with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0115] Example 12

[0116] 1. The raw materials of each component of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material include: 42 wt% bio-based polyamide resin PA56 / 5T-B, 40 wt% continuous long glass fiber (1200 Tex), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 6 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (compounded by EBS and PE wax at a mass ratio of 1:1), 0.6 wt% antioxidant (compounded by antioxidant 1098 and antioxidant 608 at a mass ratio of 1:1).

[0117] 2. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite was prepared in the same way as example 1. Long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm were obtained, which contained continuous long fibers inside the long particles with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0118] Example 13

[0119] 1. The raw materials of each component of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite included: 42 wt% bio-based polyamide resin PA56 / 5T-C, 40 wt% continuous long glass fiber (1200 Tex), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 6 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (EBS and PE wax were compounded in a mass ratio of 1:0.5), 0.6 wt% antioxidant (antioxidant 1098 and antioxidant 608 were compounded in a mass ratio of 1:1).

[0120] 2. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite was prepared in the same way as example 1. Long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm were obtained, which contained continuous long fibers inside the long particles with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0121] Example 14

[0122] 1. The raw materials of each component of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite included: 42 wt% bio-based polyamide resin PA56 / 5T-C, 40 wt% continuous long glass fiber (1200 Tex), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 6 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (EBS and PE wax were compounded in a mass ratio of 1:1), 0.6 wt% antioxidant 1098.

[0123] 2. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite was prepared in the same way as example 1. Long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12 mm were obtained, which contained continuous long fibers inside the long particles with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0124] Comparative Example 1

[0125] 1. The raw materials of each component of the polyamide composite material include: 42 wt% polyamide resin PA6, 40 wt% continuous long glass fiber (1200 Tex), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 6 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (EBS and PE wax are compounded in a mass ratio of 1:1), 0.6 wt% antioxidant 1098 (antioxidant 1098 and antioxidant 608 are compounded in a mass ratio of 1:1).

[0126] 2. The preparation method of the polyamide composite material:

[0127] S1, after stirring and mixing the raw materials of each component (except continuous long glass fiber), the mixture is placed in the main feeding hopper of the twin-screw extruder and discharged, and then melted and extruded by the twin-screw extruder; wherein the length-diameter ratio of the screw of the twin-screw extruder is 36:1, and the processing temperature from zone 1 to zone 5 to the head is 210℃, 230℃, 250℃, 260℃, 270℃, 290℃ respectively, and the screw extrusion speed is 300r / min.

[0128] S2, the melt obtained in S1 is transported to the impregnation die through the extruder die, the width of the impregnation die is 300mm, the temperature of the impregnation die is controlled at 290℃, and then the continuous long glass fiber is pulled into the impregnation die at a pulling speed of 25m / min, the impregnation occurs by pulling the melt and the continuous long fiber, and then the composite material is guided out from the die plate (the first die plate has a hole diameter of 4mm, and the second die plate has a hole diameter of 6mm), and then cooled, the processing temperature of the die plate is 280℃, and the content of the continuous long glass fiber in the composite material is controlled at 40wt% during the process, the temperature of the circulating water in the water cooler is set to 23℃ during the cooling, and the polyamide long particles with a length of 12mm are obtained by the granulator, which contain continuous long fibers with a length comparable to that of the long particles. The sample performance parameters are shown in Table 1.

[0129] Comparative Example 2

[0130] 1. The raw materials of each component of the polyamide composite material include: 42 wt% polyamide resin PA6, 40 wt% continuous long carbon fiber (24K), 10 wt% halogen-free flame retardant aluminum diethyl phosphinate, 6 wt% toughening agent POE-g-MAH, 1 wt% flow modifier dodecanedioic acid, 0.4 wt% lubricant (EBS and PE wax are compounded in a mass ratio of 1:1), 0.6 wt% antioxidant (antioxidant 1098 and antioxidant 608 are compounded in a mass ratio of 1:1).

[0131] 2. The preparation method of the polyamide composite material is the same as that of Example 8. Polyamide long particles with a length of 12mm are obtained. The sample performance parameters are shown in Table 1.

[0132] Comparative Example 3

[0133] The raw materials of each component of the polyamide composite are the same as those of Example 1, except that the preparation method is different:

[0134] S1, after the raw materials of each component (except for continuous long glass fiber) are stirred and mixed, they are placed in the main feeding hopper of a twin-screw extruder and discharged, and then melted and extruded by the twin-screw extruder; wherein the length-diameter ratio of the screw of the twin-screw extruder is 36:1, and the processing temperature from zone 1 to zone 5 to the head is 250℃, 280℃, 300℃, 310℃, 330℃, 340℃, respectively, and the main screw rotation speed is 300r / min.

[0135] S2, the melt obtained in S1 is transported to the impregnation die through the extruder die, the width of the impregnation die is 300mm, the temperature of the impregnation die is controlled at 315℃, and then the continuous long glass fiber is pulled into the impregnation die at a pulling speed of 70m / min, impregnation occurs between the melt and the continuous long fiber, and then the composite material is discharged from the die plate (the first die plate has a hole diameter of 4mm, and the second die plate has a hole diameter of 6mm), and then cooled, the processing temperature of the die plate is 300℃, and the content of the continuous long glass fiber in the composite material is controlled at 40wt% during the process, the temperature of the circulating water in the water cooler is set to 23℃ during cooling, and the long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles with a length of 12mm are obtained by the granulator, which contain continuous long fibers with a length comparable to that of the long particles. The performance parameters of the samples are shown in Table 1.

[0136] The samples prepared in the above examples and comparative examples are respectively tested for mechanical properties and the like. The test methods are as follows, and the test results are shown in Table 1 below.

[0137] (1) The bending test is tested according to the standard ISO-178, and the test condition is 2mm / min.

[0138] (2) The tensile test is tested according to the standard ISO-572-2, and the test condition is 5mm / min.

[0139] (3) The impact test is cantilever beam notched impact test according to the standard ISO-180 / 1A, and the test condition is 23℃.

[0140] (4) The limiting oxygen index test is tested according to the standard ISO-4589-2, and the test condition is 23℃.

[0141] (5) The surface appearance grade: a plate-shaped sample with a length of 200mm, a width of 200mm and a thickness of 1mm is injection molded, the surface of the sample is observed, and the fiber is completely exposed as grade 1, and the fiber is not exposed as grade 5.

[0142] Table 1

[0143]

[0144] From Table 1, it can be seen that Examples 1-7 are bio-based polyamide composites containing continuous long glass fibers, the tensile strength is all above 170 MPa, and Example 7 is as high as 246 MPa; the flexural modulus also increases with the increase of fiber content, and Example 7 is as high as 14.67 Gpa. The notched impact strength is all above 10 KJ / m2, and Example 1 is the highest, being 26.5 KJ / m2, and the oxygen index is all greater than 26, and Example 7 is as high as 33.7. Examples 8-10 are bio-based polyamide composites containing long carbon fibers, and the mechanical properties are higher with the same fiber content, and the flame retardant performance is good, which is because the reinforcing effect of carbon fibers is higher.

[0145] The continuous long glass fiber content in Example 1 and Comparative Example 1 is similar, but the mechanical properties obtained by Example 1 are obviously higher than those of Comparative Example 1, and the flame retardant performance of the oxygen index is also better than that of Comparative Example 1. Similarly, the long carbon fiber content in Example 8 and Comparative Example 2 is similar, and the mechanical strength obtained by Example 8 is also obviously higher than that of Comparative Example 2, and the flame retardant performance of the oxygen index is better than that of Comparative Example 2. The raw material components in Example 1 and Comparative Example 3 are similar, and the preparation process is different, which has a great influence on the performance of the composite. In summary, the mechanical properties and flame retardant properties of the bio-based polyamide composite material of the present application are more excellent.

[0146] Although the specific embodiments of the present application are described above, those skilled in the art should understand that this is only an example, and the protection scope of the present application is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present application, and such changes and modifications all fall within the protection scope of the present application.

Claims

1. A method for preparing a long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material, characterized in that, By weight percentage, the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material comprises the following components: Bio-based polyamide resin 10-60 wt%; Continuous long fibers 15–60 wt%; Halogen-free flame retardant 5-20 wt%; Other additives: 0.1–25 wt%; The bio-based polyamide resin contains the following structural units (Ⅰ), (Ⅱ), and (Ⅲ). The molar ratio of structural unit (Ⅰ) to structural unit (Ⅱ) is 1:(0.1~0.9); The molar ratio of structural unit (Ⅰ) to structural unit (Ⅲ) is 1:(0.1~0.9); The molar ratio of structural unit (II) to structural unit (III) is 1:(0.1~1.5); The bio-based polyamide resin is formed from pentanediamine and dicarboxylic acid, wherein the dicarboxylic acid includes adipic acid and terephthalic acid or a derivative thereof; The preparation method includes the following steps: S1. Mix the raw material components of the long fiber reinforced halogen-free flame retardant bio-based polyamide composite material, excluding continuous long fibers, and then melt-extrude to obtain a melt. S2. The melt obtained in step S1 is conveyed to the impregnation die head, and the temperature of the impregnation die head is controlled at 265-320°C. The continuous long fiber is drawn into the impregnation die head, and the melt and the continuous long fiber are impregnated. After being discharged from the perforated template, the melt is cooled and pelletized to obtain long fiber reinforced halogen-free flame-retardant bio-based polyamide long particles. In step S1, the melt extrusion is performed using a twin-screw extruder. The twin-screw extruder adopts a five-zone heating mode, with zone 1 temperature of 220-230℃, zone 2 temperature of 240-250℃, zone 3 temperature of 260-270℃, zone 4 temperature of 260-280℃, zone 5 temperature of 270-300℃, and die head temperature of 270-310℃. In step S2, the traction speed is controlled to be 5-50 m / min.

2. The preparation method according to claim 1, characterized in that, The content of the continuous long fibers is controlled to be 30-50 wt%; and / or, In step S2, there are two hole templates, with a hole diameter of 3 to 10 mm, and the second hole template has a hole diameter 1 to 3 mm larger than that of the first hole template.

3. A long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material, prepared by the preparation method of the long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 1 or 2.

4. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The relative viscosity of the bio-based polyamide resin is 2.0 to 3.2, and / or the number average molecular weight of the bio-based polyamide resin is 20,000 to 70,000, and / or the water content of the bio-based polyamide resin is 500 to 2,000 ppm, and / or the melting point of the bio-based polyamide resin is 260 to 330°C.

5. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The bio-based polyamide resin has a number-average molecular weight of 30,000 to 60,000; and / or, The continuous long fibers include one or a combination of several of glass fibers, carbon fibers, aramid fibers, metal fibers, boron fibers, and basalt fibers.

6. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The continuous long fiber is a continuous long glass fiber with a single filament diameter of 5–50 μm; and / or, a linear density of 1000–3600 TeX; or… The continuous long fiber is a continuous long carbon fiber with 20,000 to 30,000 filaments; and / or, the diameter of the filament is 5 to 10 μm.

7. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The continuous long fiber is a continuous long glass fiber with a single filament diameter of 10-20 μm.

8. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The halogen-free flame retardant includes any one or a combination of several of nitrogen-based organic flame retardants, phosphorus-based organic flame retardants, and inorganic flame retardants.

9. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The halogen-free flame retardant is aluminum diethylphosphonate, melamine cyanurate, aluminum hydroxide, magnesium hydroxide, or zinc borate.

10. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The other additives include compatibilizers, toughening agents, flow modifiers, lubricants, antioxidants, coupling agents, surfactants, antistatic agents, UV stabilizers, heat stabilizers, plasticizers, or nucleating agents.

11. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The other additives include 5-10 wt% toughening agent, 1-5 wt% flow modifier, 0.1-5 wt% lubricant, and 0.1-5 wt% antioxidant.

12. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 10 or 11, characterized in that, The toughening agent is a polar monomer-grafted polymer, wherein the polymer is at least one selected from polyethylene, polypropylene, ethylene-α-ethylene-octene copolymer, styrene-butadiene copolymer, polyethylene-polystyrene-polypropylene terpolymer, ethylene-propylene-butadiene terpolymer, ethylene-vinyl acetate copolymer, ethylene-acrylate copolymer, and ethylene-acrylate-glycidyl methacrylate copolymer; the polar monomer is at least one selected from maleic anhydride, fumaric acid, itaconic acid, citraconic acid, citraconic anhydride, and vinylsuccinic anhydride, and / or, The flow modifier includes at least one of organosilicon polymers, ester resins, and long-chain dicarboxylic acids, and / or... The lubricant includes one or more of the following: stearate lubricants, fatty amide lubricants, silicone powder or silicone masterbatch, PE wax, and ethylene-acrylic acid copolymers, and / or... The antioxidants include one or a combination of several of the following: hindered phenolic antioxidants, phosphite antioxidants, amine antioxidants, and thioester antioxidants.

13. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material is in the shape of long particles with a length of 3 to 30 mm, and contains continuous long fibers with a length of 3 to 30 mm inside.

14. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material contains continuous long glass fibers, with a tensile strength of 150–300 MPa, a flexural strength of 230–350 MPa, a flexural modulus of 7–15 GPa, and a notched impact strength of 10–30 KJ / m. 2 Limiting oxygen index is 25-34%; surface appearance grade is 4 or above.

15. The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material according to claim 3, characterized in that, The long fiber reinforced halogen-free flame-retardant bio-based polyamide composite material contains continuous long carbon fibers, with a tensile strength of 270–400 MPa, a flexural strength of 350–500 MPa, a flexural modulus of 15–30 GPa, and a notched impact strength of 10–30 KJ / m. 2 Limiting oxygen index is 25-34%; surface appearance grade is 4 or above.

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