Good-appearance, low-warpage and ablation-resistant polyphenyl ether polyamide composition and preparation method thereof

Abstract

The invention discloses a good-appearance, low-warpage and ablation-resistant polyphenyl ether polyamide composition and a preparation method thereof. The composition is prepared from the following raw materials in parts by weight: 10-35% of polyphenyl ether resin; 20-50% of polyamide resin; 30-32% of alkali-free glass fiber; 7-20% of a halogen-free flame retardant; 4-15% of a compatilizer; and 0.2-1% of an antioxidant. The polyphenyl ether polyamide composition prepared by the invention has the characteristics of good appearance, ablation resistance, low warping and excellent mechanical properties, improves the market competitiveness of the material, and can be applied to new energy automobile battery components and the like.

Description

Technical Field

[0001] The invention relates to the field of polymer materials, and in particular to a polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance and a preparation method thereof. Background Art

[0002] With the demand for technological innovation and lightweighting, the trend of engineering plastics replacing metal materials in the automotive field is accelerating. Polyamide materials have excellent solvent resistance, high temperature resistance and mechanical properties, and are widely used in automotive parts, electronic appliances and other fields. Among them, especially for the urgent need to lightweight the core components around the battery such as the power battery cover of new energy vehicles, due to the problems of poor appearance, large warping deformation and high water absorption, it is difficult to meet the requirements of halogen-free flame retardant reinforced polyamide 66. The chemical name of polyphenylene ether is poly 2,6-dimethyl-1,4-phenylene ether, referred to as PPO (PolyphenyleneOxide) or PPE (Polypheylene ether). As a high-performance engineering plastic, it has many advantages such as low density, low water absorption, intrinsic flame retardancy and good dimensional stability. However, the unmodified polyphenylene ether resin has high melt viscosity and is difficult to process directly. At the same time, it has poor solvent resistance and the product is prone to stress cracking. In addition, the appearance of conventional halogen-free flame retardant polyphenylene ether compositions is still poor, and it is difficult to meet the ablation resistance requirements of the power battery cover. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects and shortcomings in the prior art and to provide a polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance and a preparation method thereof.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] A polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance is composed of the following raw materials by weight: 10-35% polyphenylene ether resin; 20-50% polyamide resin; 30-32% alkali-free glass fiber; 7-20% halogen-free flame retardant; 4-15% compatibilizer; and 0.2-1% antioxidant.

[0006] In a preferred embodiment of the present invention, the polyphenylene ether resin is a low-viscosity polyphenylene ether resin having an intrinsic viscosity of 0.33-0.37 dl / g and a melt flow rate (315°C, 10kg) of 40-70 g / 10min. The low-viscosity polyphenylene ether resin preferably accounts for 15-25% of the polyphenylene ether polyamide composition.

[0007] In a preferred embodiment of the present invention, the polyamide resin comprises a low-viscosity polyamide 66 resin, an amorphous polyamide resin and a low-viscosity polyamide 6 resin. Among them, the relative viscosity of the low-viscosity polyamide 66 resin is 2.25-2.31, the number average molecular weight is 22000-28000, the melt flow rate (275°C, 2.16kg) is 150-170g / 10min, and the low-viscosity polyamide 66 resin preferably accounts for 15-25% in the polyphenylene ether polyamide composition; the glass transition temperature of the amorphous polyamide resin is 125°C, and the amorphous polyamide resin preferably accounts for 8-15% in the polyphenylene ether polyamide composition; the relative viscosity of the low-viscosity polyamide 6 resin is 2.43-2.47, and the resin preferably accounts for 2-4% in the polyphenylene ether polyamide composition.

[0008] In a preferred embodiment of the present invention, the halogen-free flame retardant is a composition of aluminum diethylphosphinate and a novel melamine polyphosphate, and the preferred content is 9-15%. Too low a content of the flame retardant will affect the flame retardant effect, and too high a content of the flame retardant will lead to a decrease in the mechanical properties of the material.

[0009] In a preferred embodiment of the present invention, the preferred ratio of aluminum diethylphosphinate to the novel melamine polyphosphate is 2:1-1:1.

[0010] In a preferred embodiment of the present invention, the alkali-free glass fiber is a composition of alkali-free round glass fiber and alkali-free flat glass fiber, wherein the fiber diameter of the alkali-free round glass fiber is 10 μm, the short cut length is 3 mm, the cross-sectional height of the alkali-free flat glass fiber is 7 μm, and the cross-sectional width is 28 μm, and the ratio of the alkali-free round glass fiber to the alkali-free flat glass fiber is 3:1.

[0011] The preparation method of the above-mentioned polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance comprises the following steps: (1) weighing each raw material according to the amount (parts by weight) of the formula; (2) putting all the components except the alkali-free glass fiber and the halogen-free flame retardant into a high-speed mixer and mixing them until they are uniform to obtain a premix A; (3) then feeding the obtained premix A into a twin-screw extruder from the main feeding port, and the alkali-free glass fiber and the halogen-free flame retardant are fed into the twin-screw extruder from two side feeds respectively by a side feeding process, and after melt extrusion, granulation, drying and other processes, a polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance is obtained.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] (1) The present invention adopts aluminum diethylphosphinate and a novel melamine polyphosphate in combination, which significantly improves the flame retardancy and ablation resistance of the polyphenylene ether polyamide composition while ensuring the mechanical properties of the matrix.

[0014] (2) The present invention adopts low-viscosity polyamide 66 resin, amorphous polyamide resin and low-viscosity polyamide 6 resin for compound use. In addition to improving the appearance of the ablation-resistant polyphenylene ether polyamide composition and providing dimensional stability and low warpage characteristics, the amorphous polyamide resin can also promote carbonization due to its molecular chain containing a benzene ring structure, thereby improving the flame retardancy and ablation resistance of the polyphenylene ether polyamide composition; the low-viscosity polyamide 6 resin can not only improve the processing fluidity of the polyphenylene ether polyamide composition, but also improve the mechanical properties of the polyphenylene ether polyamide composition.

[0015] (3) The present invention improves the warpage resistance of the polyphenylene ether polyamide composition while taking into account the material cost by using a compound of alkali-free round glass fiber and alkali-free flat glass fiber.

[0016] (4) Through the above beneficial effects, the polyphenylene ether polyamide composition exhibits excellent mechanical properties, flame retardancy and fire resistance, and has good appearance, low water absorption and anti-warping characteristics. The composition can be applied to new energy battery systems. Compared with metals and thermosetting resins used in power battery shells, it has better processing performance, structural design freedom and economic value on the basis of meeting functional requirements, thus realizing the application of new materials in new fields. DETAILED DESCRIPTION

[0017] Polyphenylene ether resin, manufacturer: Zhongmu; brand: ZM-035

[0018] Amorphous polyamide resin, manufacturer: Dongchen; brand: TM01

[0019] Polyamide 66 resin, manufacturer: Huafeng; brand: EP1106

[0020] Polyamide 6 resin, manufacturer: Hongsheng; brand: BE3250

[0021] Round glass fiber, manufacturer: Chongqing International; brand: 301HP-3-H

[0022] Flat glass fiber, manufacturer: Chongqing International; brand: 301HP-3-M4

[0023] Halogen-free flame retardant #1, diethyl aluminum hypophosphite, manufacturer: Xinhua; brand: XHPFR-M03

[0024] Halogen-free flame retardant #2, new melamine polyphosphate, commercially available

[0025] Halogen-free flame retardant #3, MPP, manufacturer: JLS; brand: PNA350

[0026] Compatibilizer, manufacturer: Jiayirong; brand: FB820

[0027] Antioxidant #1, manufacturer: Brueggemann; brand: H318

[0028] Antioxidant #2, manufacturer: Lianlong; brand: THANOX 1010

[0029] Antioxidant #3, manufacturer: DOVER CHEMICAL; brand: S-9228

[0030] According to the formulation amounts (parts by weight) in specific examples 1-4 and comparative examples 1-10 described in Table 1, polyphenylene ether resin, polyamide resin, alkali-free glass fiber, compatibilizer and antioxidant were weighed respectively, and the components except the alkali-free glass fiber and the halogen-free flame retardant were put into a high-speed mixer and mixed until uniform to obtain a premix A; then the obtained premix A was put into a twin-screw extruder from a main feeding port, and the alkali-free glass fiber and the halogen-free flame retardant were respectively put into the twin-screw extruder from two side feeds by a side feeding process, and after melt extrusion, granulation, drying treatment and other processes, a polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance was obtained.

[0031] The relevant performance tests were carried out according to the following test methods. The test results are shown in Table 2.

[0032] (1) Tensile strength: according to ISO 527 method, the specimen size is 170*10*4mm, and the test speed is 50mm / min;

[0033] (2) Notched impact strength: according to ISO 179 / 1eA method, specimen size 80*10*4mm;

[0034] (3) Appearance quality: The sample size is 150*100*3.2mm, and the visual method is used for evaluation. The appearance quality of the product is customized according to the amount of floating fibers, with a score of 1 to 10. The larger the score, the less floating fibers on the surface and the better the appearance.

[0035] (4) Flatness of the workpiece: The sample size is 150*100*3.2mm, and the evaluation is done by visual inspection. The flatness of the workpiece is scored from 1 to 10 based on the degree of warpage. The larger the score, the lower the degree of warpage and the flatter the workpiece.

[0036] (5) Vertical flammability: According to the UL94 method, the sample size is 125*10*0.8mm, and the vertical flammability of the 0.8mm thick test piece is tested. The vertical flammability that meets the UL94 V-0 level is marked as OK, and the vertical flammability that does not meet the UL94 V-0 level is marked as NG.

[0037] (6) Fire test: According to the GB / T 38031 method, the external fire test is carried out on the sample with a size of 150*100*2mm. After the test is completed, observe whether the remaining sample parts have burn-through, molten droplets, etc. If the plate structure remains basically good without burn-through, molten droplets, etc., it is considered to have passed the fire test and is recorded as OK. If it fails the fire test, it is recorded as NG.

[0038] Table 1 Component ratios of the ablation-resistant polyphenylene ether polyamide compositions in the examples and comparative examples (parts by weight)

[0039]

[0040]

[0041] Table 2 Test results of ablation-resistant polyphenylene ether polyamide compositions in Examples and Comparative Examples

[0042]

[0043] Comparison of Example 2 with Comparative Examples 2 and 7 in Table 2 shows that the addition of amorphous polyamide resin and flat glass fiber effectively improves the overall appearance quality of the material and the flatness of the product. Comparison of Example 1 with Comparative Examples 1 and 11 shows that an appropriate amount of low-viscosity polyamide 6 and compatibilizer can effectively improve the mechanical properties of the material. Comparison of Example 1 with Comparative Example 3 shows that too low a flame retardant content will seriously affect the flame retardant properties and ablation resistance of the material. Comparison of Example 1 with Comparative Examples 4 and 5 shows that the use of a compound of diethyl aluminum phosphinate and a new type of melamine polyphosphate significantly improves the flame retardant properties and ablation resistance of the polyphenylene ether polyamide composition while ensuring the mechanical properties of the matrix. Comparison of Example 1 with Comparative Examples 9 and 10 shows that the use of copper salt antioxidants can effectively improve the mechanical properties of materials.

[0044] The above description is only a preferred embodiment of the present invention, and therefore cannot be used to limit the scope of the present invention. That is, equivalent changes and modifications made according to the patent scope of the present invention and the contents of the specification should still fall within the scope of the present invention.

Claims

1. A polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance, characterized by the following: It is composed of the following raw materials in parts by weight: Polyphenylene ether resin 10-35%; polyamide resin 20-50%; alkali-free glass fiber 30-32%; halogen-free flame retardant 7-20%; compatibilizer 4-15%; antioxidant 0.2-1%.

2. A good appearance, low warpage, ablation-resistant polyphenylene ether polyamide composition according to claim 1, characterized in that the polyphenylene ether resin is a low-viscosity polyphenylene ether resin with an intrinsic viscosity of 0.33-0.37 dl / g and a melt flow rate of 40-70 g / 10 min at 315°C and 10 kg.

3. A good appearance, low warpage, ablation-resistant polyphenylene ether polyamide composition according to claim 2, characterized in that the low-viscosity polyphenylene ether resin accounts for 15-25% of the polyphenylene ether polyamide composition.

4. A polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance according to claim 1, characterized in that: the polyamide resin comprises a low-viscosity polyamide 66 resin, an amorphous polyamide resin and a low-viscosity polyamide 6 resin; wherein, The relative viscosity of low viscosity polyamide 66 resin is 2.25-2.31, the number average molecular weight is 22000-28000, and the melt flow rate is 150-170g / 10min at 275°C and 2.16kg; the glass transition temperature of amorphous polyamide resin is 125°C; the relative viscosity of low viscosity polyamide 6 resin is 2.43-2.

47.

5. A good appearance, low warpage, ablation-resistant polyphenylene ether polyamide composition according to claim 4, characterized in that: the low viscosity polyamide 66 resin accounts for 15-25% of the polyphenylene ether polyamide composition; the amorphous polyamide resin accounts for 8-15% of the polyphenylene ether polyamide composition; the resin accounts for 2-4% of the polyphenylene ether polyamide composition.

6. A polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance according to claim 1, characterized in that the halogen-free flame retardant is a composition of diethyl aluminum phosphinate and a new type of melamine polyphosphate, with a content of 9-15%.

7. A polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance according to claim 6, characterized in that the ratio of the diethyl aluminum phosphinate to the new melamine polyphosphate is 2:1-1:

1.

8. A polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance according to claim 1, characterized in that: the alkali-free glass fiber is a composition of alkali-free round glass fiber and alkali-free flat glass fiber, wherein: The fiber diameter of the alkali-free round glass fiber is 10μm, and the short cut length is 3mm; the cross-sectional height of the alkali-free flat glass fiber is 7μm, and its cross-sectional width is 28μm. The ratio of the alkali-free round glass fiber to the alkali-free flat glass fiber is 3:

1.

9. The method for preparing the polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance according to any one of claims 1 to 8, characterized in that: The steps are as follows: (1) weighing each raw material according to the amount (parts by weight) of the formula; (2) putting all components except the alkali-free glass fiber and the halogen-free flame retardant into a high-speed mixer and mixing them until they are uniform to obtain a premix A; (3) then feeding the obtained premix A into a twin-screw extruder from a main feeding port, and feeding the alkali-free glass fiber and the halogen-free flame retardant into the twin-screw extruder from two side feeds respectively by a side feeding process, and after melt extrusion, granulation, drying treatment and other processes, a polyphenylene ether polyamide composition with good appearance, low warpage and ablation resistance is obtained.

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