Polyamide composition as well as preparation method and application thereof

Abstract

The invention discloses a polyamide composition as well as a preparation method and application thereof, and belongs to the technical field of high polymer materials. The polyamide composition is prepared from the following components in parts by weight: 50 to 90 parts of polyamide resin, 5 to 20 parts of polyphenyl ether resin, 5 to 10 parts of SEBS (Styrene-Ethylene-Butylene-Styrene) elastomer, 0.2 to 0.6 part of vinyl siloxane and 10 to 50 parts of glass fiber. After the polyphenyl ether resin, the SEBS elastomer and the vinyl siloxane are introduced into the polyamide composition, the creep resistance can be improved and the water absorption can be reduced while the damping performance is ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and particularly relates to a polyamide composition, a preparation method thereof, and an application thereof. Background Art

[0002] Glass fiber reinforced polyamide has excellent mechanical strength and is widely used in the automotive field. In recent years, with the increasing demand for low noise in automobiles, polyamide resins with damping and vibration reduction properties have become a hot topic in development.

[0003] The invention patent with the publication number CN115551919A discloses a polyamide composition, which comprises one or more semi-crystalline polyamides and comprises an amorphous polyamide or a semi-crystalline copolyamide, such as PA66 / 6. The composition further comprises 15% to 60% by weight of at least one mineral or fiber reinforcing agent, and at least one mineral or fiber reinforcing agent comprises glass fiber. Although this composition can be particularly used as a vibration isolator and has more effective high-temperature noise and vibration noise and harshness damping performance than conventional polyamide compositions, the creep resistance of this composition is poor, which has an adverse effect on its application.

[0004] Therefore, it is urgent to develop a polyamide composition with creep resistance. Summary of the Invention

[0005] Based on the defects existing in the prior art, the purpose of the present invention is to provide a polyamide composition, a preparation method thereof, and an application thereof.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0007] In the first aspect, a polyamide composition provided by the present invention comprises the following components in parts by weight: 50 to 90 parts of polyamide resin, 5 to 20 parts of polyphenylene ether resin, 5 to 10 parts of SEBS elastomer, 0.2 to 0.6 parts of vinyl siloxane, and 10 to 50 parts of glass fiber. The hydrogenation degree of the SEBS elastomer is ≤92%, and the melting point of the polyamide resin is ≤275°C.

[0008] After introducing polyphenylene ether resin, SEBS elastomer, and vinyl siloxane into the polyamide composition, the present invention can improve the creep resistance and reduce the water absorption while ensuring the damping performance; among them, vinyl siloxane can crosslink with the carbon-carbon double bonds contained in the SEBS elastomer to enhance the friction of chain segment movement, thereby improving the creep resistance and damping performance of the polyamide composition.

[0009] In the present invention, the sum of the weight percentages of the polyamide resin and the polyphenylene ether resin in the polyamide composition is not less than 55%.

[0010] In the polyamide composition of the present invention, the weight parts of the polyamide resin can be 50 parts, 55 parts, 60 parts, 65 parts, 70 parts, 75 parts, 80 parts, 85 parts, 90 parts or the range composed of any two sets of values; the weight parts of the polyphenylene ether resin can be 5 parts, 10 parts, 15 parts, 20 parts or the range composed of any two sets of values; the weight parts of the SEBS elastomer can be 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts or the range composed of any two sets of values; the weight parts of the vinyl siloxane can be 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts or the range composed of any two sets of values; the weight parts of the glass fiber can be 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts or the range composed of any two sets of values.

[0011] In the present invention, the content of styrene in the SEBS elastomer is 25-65%.

[0012] Preferably, the hydrogenation degree of the SEBS elastomer is 80-90%.

[0013] In the present invention, the hydrogenation degree of the SEBS elastomer can be 80%, 85%, 88%, 90% or the range composed of any two sets of values among them.

[0014] Preferably, the vinyl siloxane includes at least one of vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, vinyltriisopropoxysilane, vinylmethyldi(trimethylsiloxy)silane.

[0015] Preferably, the polyamide resin includes at least one of PA6 resin, PA66 resin, PA10T resin, PA66 / 6 resin, PA66 / 6T resin, PA610 resin, PA612 resin, PA11 resin, PA12 resin, PA6-3-T resin, PA12 / MACMI resin, PA6I / 6T resin, PA6I / 6T / 6 resin.

[0016] Preferably, the melting point of the polyamide resin is 220-271°C.

[0017] In the present invention, the melting point of the polyamide resin can be 220°C, 230°C, 240°C, 250°C, 260°C, 270°C, 271°C or the range composed of any two sets of values among them.

[0018] More preferably, the melting point of the polyamide resin is 255-271°C. When the melting point of the polyamide resin is within 255-271°C, the comprehensive performance of the polyamide composition is better.

[0019] Preferably, the intrinsic viscosity of the polyphenylene ether resin measured in chloroform at 25 °C is 30 to 45 cm 3 / g.

[0020] In the present invention, the intrinsic viscosity of the polyphenylene ether resin measured in chloroform at 25 °C can be 30 cm 3 / g, 35 cm 3 / g, 38 cm 3 / g, 40 cm 3 / g, 45 cm 3 / g or a range composed of any two sets of these values.

[0021] Preferably, the glass fiber includes at least one of flat glass fiber and round glass fiber.

[0022] The inventors have found through research that, compared with round glass fiber, flat glass fiber can more significantly improve the creep resistance of the polyamide composition while enhancing the mechanical properties of the polyamide composition.

[0023] Preferably, the polyamide composition includes the following components in parts by weight: 60 to 70 parts of polyamide resin, 10 to 15 parts of polyphenylene ether resin, 7 to 9 parts of SEBS elastomer, 0.3 to 0.5 parts of vinyl siloxane, and 30 to 40 parts of glass fiber.

[0024] Preferably, the polyamide composition further includes 1 to 10 parts of additives, and the additives include at least one of flame retardants, lubricants, colorants, and antioxidants.

[0025] More preferably, the flame retardant includes at least one of brominated polystyrene, aluminum diethylphosphinate, and red phosphorus.

[0026] More preferably, the lubricant includes at least one of PE wax, stearate, and pentaerythritol ester.

[0027] More preferably, the colorant includes at least one of carbon black, titanium dioxide, and zinc sulfide.

[0028] More preferably, the antioxidant includes at least one of hindered phenol antioxidants and phosphite antioxidants.

[0029] More preferably, in the polyamide composition, the weight parts of the flame retardant are 5 to 10 parts, the weight parts of the lubricant are 0.2 to 1 part, the weight parts of the colorant are 0.2 to 1 part, and the weight parts of the antioxidant are 0.2 to 1 part.

[0030] In the present invention, the test method for the hydrogenation degree of the SEBS elastomer is Q / SH.1085 1221-2006;

[0031] The test method for the melting point of the polyamide resin is ISO 11357-3:2011, with a heating rate of 10 °C / min;

[0032] The test method for the intrinsic viscosity of the polyphenylene ether resin is GB / T 1632.1-2008, and the test conditions are: solvent chloroform, temperature 25 °C.

[0033] In a second aspect, a method for preparing a polyamide composition as described in the first aspect of the present invention includes the following steps:

[0034] Mix the components except glass fiber and melt-blend and extrude through a twin-screw extruder, and granulate. The glass fiber is added from the side feed to obtain the polyamide composition.

[0035] In a third aspect, an application of a polyamide composition as described in the first aspect of the present invention in the preparation of automotive parts is provided.

[0036] The automotive parts may be vibration isolation fittings of automotive internal combustion engines, automotive radiator fans, battery brackets of automotive battery packs, etc.

[0037] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0038] After introducing polyphenylene ether resin, SEBS elastomer and vinyl siloxane into the polyamide composition, the present invention can improve the creep resistance and reduce the water absorption while ensuring the damping performance. Specific Embodiments

[0039] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments and comparative examples. The purpose is to understand the content of the present invention in detail, rather than limiting the present invention. All other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

[0040] The source information and performance parameters of the components in each embodiment and comparative example are shown in Table 1 below.

[0041] Table 1

[0042]

[0043]

[0044] In Table 1, the test method for the hydrogenation degree is Q / SH.1085 1221-2006;

[0045] The test method for the melting point is ISO 11357-3:2011, with a heating rate of 10 °C / min;

[0046] The test method for intrinsic viscosity is GB / T 1632.1-2008, and the test conditions are: solvent chloroform, temperature 25°C.

[0047] Unless otherwise specified, the component raw materials used in each example and comparative example of the present invention are all commercially available raw materials, and the component raw materials used in each parallel experiment are the same kind.

[0048] Examples 1 to 16 and Comparative Examples 1 to 5

[0049] For the examples and comparative examples of the polyamide composition of the present invention, the components and their weight ratios of the polyamide composition are shown in Tables 2 to 3.

[0050] The preparation method of the polyamide composition includes the following steps:

[0051] Mix the components except glass fiber and melt-blend and extrude through a twin-screw extruder to granulate. The glass fiber is added from the side feed to obtain the polyamide composition. The temperatures of each zone of the twin-screw extruder from the feeding section to the head are: 260°C, 240°C, 240°C, 240°C, 280°C. The screw speed of the twin-screw extruder is 180 rpm, and the length-diameter ratio of the screw is 40:1.

[0052] Table 2 (unit: parts by weight)

[0053]

[0054]

[0055] Table 3 (unit: parts by weight)

[0056]

[0057] In order to verify the performance of the composition of the present invention, the compositions prepared in each example and comparative example are used as samples for the following performance tests:

[0058] (1) Damping performance: The DMA three-point bending test is used, the frequency is 1 Hz, the temperature range is -30°C to 120°C, and the temperature rise rate is 3°C / min. The tanδ of the material is measured to obtain the peak value of tanδ in the range of 60°C to 80°C;

[0059] (2) Water absorption: Test according to ISO62 standard, the test temperature is 23°C, and the test humidity is 50% R.H;

[0060] (3) Creep resistance: Injection molding is used to prepare samples, ISO 527-1-2019 tensile specimens are used, the fixed load is 20 MPa, the ambient temperature is 60°C, and the deformation data after 168 h of testing is recorded.

[0061] The test results are shown in Tables 4 - 5.

[0062] Table 4

[0063]

[0064]

[0065] Table 5

[0066]

[0067] As can be seen from Tables 4 - 5, the polyamide compositions prepared in the embodiments of the present invention all have good damping performance and creep resistance, and low water absorption rate. Specifically: the damping factor is not less than 0.11, the creep rate is not higher than 0.3%, and the water separation rate is not higher than 0.7%.

[0068] As can be seen from Example 1, Examples 5 - 7 and Comparative Example 1, when the melting point of the polyamide is 255 - 271 °C, the creep resistance of the polyamide composition is better.

[0069] As can be seen from Example 1, Examples 10 - 12 and Comparative Examples 2 and 4, introducing an SEBS elastomer with a hydrogenation degree not greater than 90% can significantly improve the comprehensive performance of the polyamide composition.

[0070] As can be seen from Example 1, Examples 13 - 15 and Comparative Example 3, introducing vinyl siloxane can effectively improve the creep resistance and damping property of the polyamide composition.

[0071] Compared with Example 1, polyphenylene ether resin was not added in Comparative Example 5, resulting in significant deterioration of the water absorption rate and creep resistance of the polyamide composition.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A polyamide composition, characterized in that The invention comprises the following components in parts by weight: 50-90 parts of polyamide resin, 5-20 parts of polyphenylene ether resin, 5-10 parts of SEBS elastomer, 0.2-0.6 parts of vinyl siloxane and 10-50 parts of glass fiber. The hydrogenation degree of the SEBS elastomer is ≤92% and the melting point of the polyamide resin is ≤275°C.

2. The polyamide composition according to claim 1, characterized in that The hydrogenation degree of the SEBS elastomer is 80-90%.

3. The polyamide composition according to claim 1, characterized in that: The vinyl siloxane includes at least one of vinyl triethoxysilane, vinyl trimethoxysilane, vinyl tri-(2-methoxyethoxy)-silane, vinyl triisopropoxysilane, and vinyl methyl bis(trimethylsiloxy)silane.

4. The polyamide composition according to claim 1, characterized in that: The polyamide resin includes at least one of PA6 resin, PA66 resin, PA10T resin, PA66 / 6 resin, PA66 / 6T resin, PA610 resin, PA612 resin, PA11 resin, PA12 resin, PA6-3-T resin, PA12 / MACMI resin, PA6I / 6T resin, and PA6I / 6T / 6 resin.

5. The polyamide composition according to claim 1, characterized in that: The melting point of the polyamide resin is 220-271°C.

6. The polyamide composition according to claim 1, characterized in that: The intrinsic viscosity of the polyphenylene ether resin measured in chloroform at 25°C is 30 to 45 cm 3 / g.

7. The polyamide composition according to claim 1, characterized in that: The invention comprises the following components in parts by weight: 60-70 parts of polyamide resin, 10-15 parts of polyphenylene ether resin, 7-9 parts of SEBS elastomer, 0.3-0.5 parts of vinyl siloxane and 30-40 parts of glass fiber.

8. The polyamide composition according to claim 1, characterized in that: The invention also comprises 1 to 10 parts of auxiliary agents, wherein the auxiliary agents comprise at least one of a flame retardant, a lubricant, a colorant and an antioxidant.

9. A method for preparing a polyamide composition according to any one of claims 1 to 8, characterized in that: The following steps are involved: The components except the glass fiber are mixed and extruded through a twin-screw extruder for melt blending and granulation, and the glass fiber is fed from the side to obtain the polyamide composition.

10. Use of the polyamide composition according to any one of claims 1 to 8 in the preparation of automobile parts.

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