High-filling high-heat-resistance flame-retardant nylon material for electric vehicle and preparation method thereof

Abstract

The invention discloses a high-filling high-heat-resistance flame-retardant nylon material and a preparation method thereof, and belongs to the technical field of high polymer materials. The nylon material is prepared from the following components in parts by weight: 20-40 parts of homopolymerized nylon resin, 5-20 parts of copolymerized nylon resin, 10-20 parts of a filling agent, 30-50 parts of magnesium hydroxide, 0.5-5 parts of a flame-retardant synergist, 8-20 parts of a composite toughening agent, 0.5-2 parts of a heat stabilizer and 0.5-1 part of other auxiliaries. Dual effects are achieved through the composite toughening agent: the non-grafted component promotes molecular chain slippage, and the fluidity and low-temperature toughness of a high filling system are remarkably improved; and the grafted component strengthens the interfacial compatibility and blocks powder agglomeration. And in combination with a long-acting heat stabilizer, thermal oxidation degradation in the high-shear injection molding process is effectively inhibited, the defects of material spraying, material flower and the like are thoroughly eliminated, and stable production of large-size guard plate type components is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and in particular to a highly filled, heat-resistant and flame-retardant nylon material for electric vehicles and a preparation method thereof. Background Art

[0002] Electric vehicle materials must simultaneously meet three core requirements: improved flame retardancy (reducing fire risk), limited plastic usage (≤ 5.5% of the vehicle's total mass), and lightweight design. Existing highly filled flame-retardant nylon materials, in order to control costs, generally face two major technical bottlenecks:

[0003] 1. Insufficient thermal stability: Heat retention during the molding process causes material degradation, resulting in defects such as spraying and material flowers, making it difficult to meet the long-cycle injection molding requirements of large-size parts (such as guard plates);

[0004] 2. Toughness does not meet the standard: After high filling, the low-temperature drop cone impact performance is significantly reduced and cannot pass the crash resistance test.

[0005] Prior art, CN103044912A discloses a halogen-free flame-retardant continuous long glass fiber reinforced polyamide 66 composite material. By combining polyamide 66, a toughening agent, a halogen-free flame retardant, and long glass fibers, it achieves high fluidity, heat resistance, and flame retardancy. However, it does not address improvements in low-temperature drop cone impact performance. Summary of the Invention

[0006] In view of this, the present invention provides a high-filling, high-heat-resistant and flame-retardant nylon material for electric vehicles and a preparation method thereof to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions:

[0008] In a first aspect, the present invention discloses a highly filled, heat-resistant, flame-retardant nylon material, which is prepared from the following components in parts by weight:

[0009]

[0010]

[0011] As a further embodiment of the present invention, the viscosity of the homopolymer nylon resin is 2.0 to 2.8 dl / g.

[0012] As a further solution of the present invention: the copolymer nylon resin is at least one of PA6 / 66, PA6 / 612, PA66 / 6, PA6 / 610, and PA610 / 612.

[0013] As a further solution of the present invention: the filler is one of glass fiber treated with a silane coupling agent, glass powder, talcum powder, wollastonite, calcium carbonate, kaolin,

[0014] As a further solution of the present invention: the magnesium hydroxide is at least one of flaky magnesium hydroxide, magnesium hydroxide whiskers, and nano-scale magnesium hydroxide that has been surface-treated with organosilicon, and its hydrophobicity is above 98%.

[0015] As a further solution of the present invention: the flame retardant synergist is at least one of zinc hydroxystannate, potassium pentaborate, and molecular sieves.

[0016] As a further solution of the present invention: the composite toughening agent is at least two of grafted / non-grafted polyolefin elastomer composites, polyethylene, EVA, EPDM, and SEBS; and the grafting monomer is selected from one of maleic anhydride, GMA, and EMA.

[0017] As a further embodiment of the present invention: the heat stabilizer is at least one of copper salt, diethylene glycol, pentaerythritol, dipentaerythritol, phosphate, triethylamine, and S-EED.

[0018] As a further solution of the present invention: the other auxiliary agent is at least one of a lubricant, a nucleating agent, a light stabilizer, and a flow modifier.

[0019] In a second aspect, the present invention discloses a method for preparing the highly filled, highly heat-resistant, flame-retardant nylon material as described above, comprising the following steps:

[0020] The homopolymer nylon resin, the copolymer nylon resin, the flame retardant synergist, the composite toughening agent, the heat stabilizer, and other additives are fully mixed according to parts by weight to obtain a mixture;

[0021] The mixed material is added from the main feeding port of the twin-screw extruder, and at the same time, the filler is added through the first side feeding port and the magnesium hydroxide is added through the second side feeding port, and the mixture is melt-blended, extruded, drawn, and granulated to obtain a highly filled and heat-resistant flame-retardant nylon material;

[0022] Wherein, the temperature of each zone of the twin-screw extruder is 190-210°C, 190-210°C, 230-250°C, 230-250°C, 230-250°C, 230-250°C, 230-250°C, 230-240°C, 230-240°C, 230-240°C, the head temperature is 220-230°C, and the screw speed is 500-700r / min.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] This invention utilizes a composite toughening agent to achieve dual effects: the non-grafted component promotes molecular chain slip, significantly improving the fluidity and low-temperature toughness of highly filled systems; the grafted component strengthens interfacial compatibility and prevents powder agglomeration. Combined with a long-lasting thermal stabilizer, it effectively inhibits thermal oxidative degradation during high-shear injection molding, completely eliminating defects such as spraying and sprue, ensuring stable production of large-scale guard plate components (molding cycle > 120 seconds).

[0025] A flame retardant system using hydrophobic flaky / whisker magnesium hydroxide combined with a synergist achieves UL94 V0 rating (1.6mm) while reducing flame retardant usage by 20%, while also avoiding the mechanical performance degradation associated with traditional magnesium hydroxide. Combined with low-density fillers such as glass powder, the material's density is significantly reduced, meeting the new national standard for lightweight rigidity, which requires a plastic content of ≤5.5%.

[0026] The introduction of copolymer nylon resin lowers the melting temperature by approximately 15°C, enhancing melt encapsulation of powder materials and significantly improving the surface finish of finished products. The material's melt index reaches 25-30g / 10min, enabling thin-wall designs of less than 1mm. With all raw materials replaced by domestically sourced materials, the cost is significantly lower than imported glass fiber reinforcement solutions, meeting the cost reduction needs of the electric vehicle industry. DETAILED DESCRIPTION

[0027] To facilitate understanding of the present invention, the present invention will be described more fully below in conjunction with specific embodiments. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to provide a more thorough and comprehensive understanding of the disclosure of the present invention.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0029] The specific information of the raw materials used in the following examples and comparative examples is as follows:

[0030] Homopolymer nylon resin: PA6 YH800 (Yueyang Petrochemical Co., Ltd.), HY2200 (Jiangsu Haiyang Chemical Co., Ltd.), HY2000 (Jiangsu Haiyang Chemical Co., Ltd.);

[0031] Copolymer nylon resin: PA66 / 6 (INVISTA), PA6 / 66 (Hangzhou Juheshun Co., Ltd.);

[0032] Fillers: glass powder (Guangdong Yuanlei Powder Material Co., Ltd.), talc powder BHS 505 (Liaoning Aihai Talc Co., Ltd.), wollastonite KT-active powder (Jiangxi Kete Fine Powder Co., Ltd.);

[0033] Magnesium hydroxide: H1411N (Weifang Haililong Magnesium Industry Co., Ltd.), H1611 (Weifang Haililong Magnesium Industry Co., Ltd.), FR 2801T (Hefei Zhongke Flame Retardant New Materials Co., Ltd.);

[0034] Flame retardant synergists: zinc hydroxystannate (Jiangxi Renben Technology Co., Ltd.), potassium pentaborate (Jiangyin Shell Chemical Co., Ltd.), molecular sieve (Qingdao Ocean Molecular Sieve Co., Ltd.);

[0035] Composite toughening agent: MAH-POE KT913 (Shenyang Ketong Co., Ltd.), MAH-SEBS FG1901 (Katon), POE8200 (Dow Chemical), SEBS 792 (Yueyang Petrochemical);

[0036] Heat stabilizer: H318 (Brüggemann), triethylamine (Baiyang Biotechnology Co., Ltd.), H161 (Brüggemann), dipentaerythritol (Hubei Yihua Chemical), 1098 (BASF);

[0037] Other additives: EBS lubricant (Kao, Japan); hyperbranched polymer flow modifier, C100 (Wuhan Hyperbranched Chemical Company)

[0038] All materials are commercially available common products.

[0039] It is understood that the above raw materials and reagents are only examples of some specific embodiments of the present invention, which make the technical solution of the present invention clearer, and do not mean that the present invention can only adopt the above reagents. The specific scope in the claims shall prevail. In addition, the "parts" described in the examples and comparative examples, unless otherwise specified, refer to parts by weight.

[0040] Any range described in the present invention includes the end value and any numerical value between the end values ​​and any sub-range formed by the end value or any numerical value between the end values.

[0041] Example 1

[0042] 20 parts of PA6 resin (HY2200), 15 parts of PA6 / 66 copolymer nylon, 0.5 parts of zinc hydroxystannate, 8 parts of toughening agent KT913, 12 parts of toughening agent 8200, 0.3 parts of heat stabilizer H318, 0.2 parts of dipentaerythritol, and 0.5 parts of EBS lubricant were placed in a high-pressure mixer and thoroughly mixed to obtain a mixture;

[0043] The mixed material is added from the main feeding port of the twin-screw extruder. At the same time, 20 parts of glass powder are added through the first side feeding port, and 30 parts of magnesium hydroxide (H1411N) and 20 parts of magnesium hydroxide (H1611) are added through the second side feeding port. After melt blending, extrusion, drawing, and granulation, a highly filled and heat-resistant flame-retardant nylon material is obtained;

[0044] Wherein, the temperatures of each zone of the twin-screw extruder are 190°C, 210°C, 240°C, 230°C, 235°C, 250°C, 250°C, 240°C, 230°C, and 230°C in sequence; the head temperature is 220°C, and the screw speed is 500r / min.

[0045] Example 2

[0046] 40 parts of PA6 resin (HY2200), 5 parts of PA6 / 66 copolymer nylon, 0.6 parts of zinc hydroxystannate, 0.4 parts of potassium pentaborate, 8 parts of toughening agent KT913, 8 parts of toughening agent 8200, 0.2 parts of heat stabilizer H318, 0.2 parts of triethylamine, 0.6 parts of dipentaerythritol, 0.5 parts of EBS lubricant, and 0.5 parts of C100 flow modifier were placed in a high-speed mixer and thoroughly mixed to obtain a mixture;

[0047] The mixed material is added from the main feeding port of the twin-screw extruder. At the same time, 11 parts of glass powder are added through the first side feeding port, and 20 parts of magnesium hydroxide (H1411N) and 20 parts of magnesium hydroxide (H1611) are added through the second side feeding port. After melt blending, extrusion, drawing, and granulation, a highly filled and heat-resistant flame-retardant nylon material is obtained;

[0048] Wherein, the temperatures of each zone of the twin-screw extruder are 200°C, 210°C, 245°C, 235°C, 235°C, 250°C, 250°C, 240°C, 230°C, and 235°C in sequence; the head temperature is 225°C, and the screw speed is 700r / min.

[0049] Example 3

[0050] 40 parts of PA6 resin (HY2000), 5 parts of PA66 / 6 copolymer nylon, 1 part of zinc hydroxystannate, 1 part of molecular sieve, 5 parts of toughening agent FG1901, 3 parts of toughening agent SEBS 792, 1.4 parts of triethylamine, 0.6 parts of heat stabilizer H161, and 1 part of C100 flow modifier were placed in a high-speed mixer and thoroughly mixed to obtain a mixture;

[0051] The mixed material is added from the main feeding port of the twin-screw extruder. At the same time, 15 parts of talc powder are added through the first side feeding port and 30 parts of magnesium hydroxide (H1411N) are added through the second side feeding port. After melt blending, extrusion, drawing and granulation, a highly filled and heat-resistant flame-retardant nylon material is obtained;

[0052] Among them, the temperatures of each zone of the twin-screw extruder are 200℃, 210℃, 230℃, 235℃, 240℃, 245℃, 250℃, 240℃, 230℃, and 240℃ respectively; the head temperature is 225℃, and the screw speed is 550r / min.

[0053] Example 4

[0054] 15 parts of PA6 resin (HY2000), 10 parts of PA6 resin (YH800), 20 parts of PA6 / 66 copolymer nylon, 3 parts of zinc hydroxystannate, 5 parts of toughening agent FG1901, 5 parts of toughening agent SEBS 792, 1 part of heat stabilizer H161, and 0.6 part of EBS lubricant were placed in a high-speed mixer and thoroughly mixed to obtain a mixture;

[0055] The mixed material was added from the main feeding port of the twin-screw extruder. At the same time, 10 parts of wollastonite KT-active powder were added through the first side feeding port and 35 parts of magnesium hydroxide (H1611) were added through the second side feeding port. After melt blending, extrusion, drawing and granulation, a highly filled and heat-resistant flame-retardant nylon material was obtained.

[0056] Among them, the temperatures of each zone of the twin-screw extruder are 190℃, 195℃, 235℃, 240℃, 235℃, 250℃, 250℃, 240℃, 235℃, and 235℃ respectively, the head temperature is 230℃, and the screw speed is 650r / min.

[0057] Comparative Example 1

[0058] 35 parts of PA6 resin (HY2200), 0.5 parts of zinc hydroxystannate, 8 parts of toughener KT913, 12 parts of toughener 8200, 0.3 parts of heat stabilizer H318, 0.2 parts of dipentaerythritol, and 0.5 parts of EBS lubricant were placed in a high-pressure mixer and thoroughly mixed to obtain a mixture;

[0059] The mixed material is added from the main feeding port of the twin-screw extruder. At the same time, 20 parts of glass powder are added through the first side feeding port, and 30 parts of magnesium hydroxide (H1411N) and 20 parts of magnesium hydroxide (H1611) are added through the second side feeding port. After melt blending, extrusion, drawing, and granulation, a highly filled and heat-resistant flame-retardant nylon material is obtained;

[0060] Wherein, the temperatures of each zone of the twin-screw extruder are 190°C, 210°C, 240°C, 230°C, 235°C, 250°C, 250°C, 240°C, 230°C, and 230°C in sequence; the head temperature is 220°C, and the screw speed is 500r / min.

[0061] Comparative Example 2

[0062] 20 parts of PA6 resin (HY2200), 15 parts of PA6 / 66 copolymer nylon, 0.5 parts of zinc hydroxystannate, 20 parts of toughening agent 8200, 0.3 parts of heat stabilizer H318, 0.2 parts of dipentaerythritol, and 0.5 parts of EBS lubricant were placed in a high-pressure mixer and thoroughly mixed to obtain a mixture;

[0063] The mixed material is added from the main feeding port of the twin-screw extruder. At the same time, 20 parts of glass powder are added through the first side feeding port, and 30 parts of magnesium hydroxide (H1411N) and 20 parts of magnesium hydroxide (H1611) are added through the second side feeding port. After melt blending, extrusion, drawing, and granulation, a highly filled and heat-resistant flame-retardant nylon material is obtained;

[0064] Wherein, the temperatures of each zone of the twin-screw extruder are 190°C, 210°C, 240°C, 230°C, 235°C, 250°C, 250°C, 240°C, 230°C, and 230°C in sequence; the head temperature is 220°C, and the screw speed is 500r / min.

[0065] Comparative Example 3

[0066] 20 parts of PA6 resin (HY2200), 15 parts of PA6 / 66 copolymer nylon, 0.5 parts of zinc hydroxystannate, 20 parts of toughening agent KT913, 0.3 parts of heat stabilizer H318, 0.2 parts of dipentaerythritol, and 0.5 parts of EBS lubricant were placed in a high-speed mixer and thoroughly mixed to obtain a mixture;

[0067] The mixed material is added from the main feeding port of the twin-screw extruder. At the same time, 20 parts of glass powder are added through the first side feeding port, and 30 parts of magnesium hydroxide (H1411N) and 20 parts of magnesium hydroxide (H1611) are added through the second side feeding port. After melt blending, extrusion, drawing, and granulation, a highly filled and heat-resistant flame-retardant nylon material is obtained;

[0068] Wherein, the temperatures of each zone of the twin-screw extruder are 190°C, 210°C, 240°C, 230°C, 235°C, 250°C, 250°C, 240°C, 230°C, and 230°C in sequence; the head temperature is 220°C, and the screw speed is 500r / min.

[0069] The nylon materials obtained in the examples and comparative examples were subjected to the following tests, and the test results are shown in Table 1.

[0070] Mechanical properties: Tensile strength is tested according to ISO527, bending deflection is tested according to ISO 178, and notched Izod impact strength is tested according to ISO180.

[0071] Flowability test: Melt index is tested according to ISO1133.

[0072] Evaluation of molding heat retention performance: The injection molding machine is set to 300℃ and hold for 2 minutes. The molded parts are visually inspected to observe the nozzle spraying situation and the degree of material flower on the surface.

[0073] Falling Cone Impact: Prepare samples (100x100x2mm, 5 per group) and apply a 3kg falling cone from a height of 500mm to the samples. Visually observe the extent of cracking and breakage. Test at room temperature (23°C). Low-temperature test: Samples are placed at -40°C for 4 hours, then impact tested within 30 seconds.

[0074] Table 1

[0075]

[0076]

[0077] From the comparison of the results in Table 1, it can be seen that compared with the comparative example, the embodiment of the present invention has higher fluidity, which is conducive to the large and thin injection molding of the product, and meets the lightweight design requirements of electric vehicles taking into account high-filling materials; the present invention also has greater bending deflection and low-temperature drop cone impact performance, showing improved toughness, and meeting the impact resistance requirements of electric vehicles; the heat retention evaluation experiment shows that the embodiment of the present invention has higher thermal stability, shows fewer molding manufacturing defects such as spraying and material flowers, and has higher thermal stability, which meets the long-term stable molding requirements of large-size components of electric vehicles.

[0078] From the comparison between Example 1 and Comparative Example 1, it can be seen that the lack of copolymerized nylon in Comparative Example 1 leads to a significant decrease in the fluidity of the material (melt index 5.6), a 43% decrease in bending toughness, and complete failure under low-temperature impact (broken at -40°C).

[0079] From the comparison between Example 1 and Comparative Example 2, it can be seen that Comparative Example 2 lacks the MAH-POE grafting component, resulting in a decrease in the flame retardant properties of the material and a 36% decrease in impact strength.

[0080] A comparison of Example 1 and Comparative Example 3 shows that the lack of the non-grafted POE component in Comparative Example 3 leads to poor material flowability and a 52% decrease in impact strength. A comprehensive analysis of Examples 1, 2, and 3 demonstrates that the grafted and non-grafted components in the composite toughening agent work synergistically. The grafted component acts as a "binder" to resolve the interface conflicts between the filler / flame retardant and the matrix, while the non-grafted component acts as a "lubricant + buffer layer," resolving conflicts between processing flowability and impact energy transfer. Both are essential.

[0081] Although this specification is described according to implementation methods, not every implementation method contains only one independent technical solution. This narrative method of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

[0082] Therefore, the above description is only a preferred embodiment of the present application and is not intended to limit the scope of implementation of the present application; that is, all equivalent modifications made according to the scope of the claims of the present application are within the scope of protection of the claims of the present application.

Claims

1. A high-filling, high-heat-resistant, flame-retardant nylon material for electric vehicles, characterized in that: It is prepared from the following components in parts by weight:

2. The high-filled, high-heat-resistant, flame-retardant nylon material for electric vehicles according to claim 1, characterized in that: The viscosity of the homopolymer nylon resin is 2.0-2.8 dl / g.

3. The high-filled, high-heat-resistant, flame-retardant nylon material for electric vehicles according to claim 1, characterized in that: The copolymer nylon resin is at least one of PA6 / 66, PA6 / 612, PA66 / 6, PA6 / 610, and PA610 / 612.

4. The high-filled, high-heat-resistant, flame-retardant nylon material for electric vehicles according to claim 1, characterized in that: The filler is one of glass fiber treated with a silane coupling agent, glass powder, talcum powder, wollastonite, calcium carbonate and kaolin.

5. The high-filled, high-heat-resistant, flame-retardant nylon material for electric vehicles according to claim 1, characterized in that: The magnesium hydroxide is at least one of flaky magnesium hydroxide, magnesium hydroxide whiskers and nano-magnesium hydroxide that have been surface-treated with organic silicon, and its hydrophobicity is above 98%.

6. The high-filled, high-heat-resistant, flame-retardant nylon material for electric vehicles according to claim 1, characterized in that: The flame retardant synergist is at least one of zinc hydroxystannate, potassium pentaborate, and molecular sieves.

7. The high-filled, high-heat-resistant, flame-retardant nylon material for electric vehicles according to claim 1, characterized in that: The composite toughening agent is at least two of grafted / non-grafted polyolefin elastomer composite, polyethylene, EVA, EPDM, and SEBS; and the grafting monomer is selected from one of maleic anhydride, GMA, and EMA.

8. The high-filled, high-heat-resistant, flame-retardant nylon material for electric vehicles according to claim 1, characterized in that: The heat stabilizer is at least one of copper salt, diethylene glycol, pentaerythritol, dipentaerythritol, phosphate, triethylamine, and S-EED.

9. The high-filled, high-heat-resistant, flame-retardant nylon material for electric vehicles according to claim 1, characterized in that: The other additives are at least one of a lubricant, a nucleating agent, a light stabilizer, and a flow modifier.

10. The method for preparing a high-filling, high-heat-resistant, flame-retardant nylon material for electric vehicles according to any one of claims 1 to 9, characterized in that: The following steps are involved: The homopolymer nylon resin, the copolymer nylon resin, the flame retardant synergist, the composite toughening agent, the heat stabilizer, and other additives are fully mixed according to parts by weight to obtain a mixture; The mixed material is added from the main feeding port of the twin-screw extruder, and at the same time, the filler is added through the first side feeding port and the magnesium hydroxide is added through the second side feeding port, and the mixture is melt-blended, extruded, drawn, and granulated to obtain a highly filled and heat-resistant flame-retardant nylon material; Wherein, the temperature of each zone of the twin-screw extruder is 190-210°C, 190-210°C, 230-250°C, 230-250°C, 230-250°C, 230-250°C, 230-250°C, 230-240°C, 230-240°C, 230-240°C, the head temperature is 220-230°C, and the screw speed is 500-700r / min.

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