A low-noise polyamide material and its preparation method and application

Abstract

The present invention relates to a low-noise polyamide material and a preparation method and application thereof. The low-noise polyamide material comprises the following components: polyamide resin, polyamide elastomer, glass fiber, benzenesulfonamide plasticizer and silicone. The polyamide material uses a specific polyamide resin as a base resin, and then through the combination of benzenesulfonamide plasticizer, silicone and polyamide elastomer with PA6 as a hard segment, the obtained polyamide material has low noise and good low-temperature impact resistance.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer materials, and more specifically to a low-noise polyamide material and a preparation method and application thereof. Background Art

[0002] During the driving process, the auto parts are in a frequent vibration environment, and the friction between the parts often produces "squeaking, squeaking" noises, which cause trouble to the driver or passengers. Polyamide composite materials are often used as car handles, car drag chains and other parts due to their high strength and high rigidity. Similarly, when subjected to the vibration of the working environment, polyamide composite materials will also produce abnormal noises.

[0003] Patent CN103788629A discloses a high wear-resistant, low-noise glass fiber reinforced nylon composite material composition, which is added with bronze powder, modifier ABS, etc. to obtain a low-noise nylon composite material.

[0004] However, the above scheme achieves low noise effect by compounding ABS, but the compatibility of the two is poor, which will lead to low low-temperature impact resistance. Compared with the toughness at room temperature (about 25°C), the low-temperature (-40 to -60°C) toughness of polyamide composites is increasingly valued. Common toughening agents such as acid-modified olefin elastomers can improve the room-temperature toughness of polyamide composites, but the effect of improving low-temperature toughness is not good; and if the low-temperature impact resistance is low, it will cause the parts made of the material to be easily brittle during installation or use in cold weather, limiting its application.

[0005] Therefore, new technologies need to be developed to solve the problem that current polyamide composite materials cannot provide both low noise and good low-temperature impact resistance. Summary of the invention

[0006] The primary purpose of the present invention is to overcome the problem that the polyamide composite material in the current technology cannot take into account both low noise and good low temperature impact resistance, and to provide a low noise polyamide material. The present invention uses a specific polyamide resin (PA6 resin or PA66 resin) as a base resin, and then through the combination of benzenesulfonamide plasticizer, silicone and polyamide elastomer with PA6 as a hard segment, the obtained polyamide material has low noise and good low temperature impact resistance.

[0007] A further object of the present invention is to provide a method for preparing the above polyamide material.

[0008] A further object of the present invention is to provide the use of the above polyamide material in the preparation of automobile door handles, dashboard brackets or drag chains.

[0009] The above-mentioned object of the present invention is achieved by the following technical solutions:

[0010] A low-noise polyamide material comprises the following components in parts by weight:

[0011]

[0012] The polyamide resin is at least one of PA6 resin or PA66 resin;

[0013] The polyamide elastomer is a copolymer composed of PA6 as a hard segment and a polyether chain segment as a soft segment.

[0014] In the present invention, the polyamide resin is used as the main resin, and its content in the polyamide material is at least 35 wt %.

[0015] In the present invention, the addition of glass fiber improves the basic mechanical properties of the polyamide material.

[0016] Research has found that polyamide elastomers have certain impact resistance. The inventors of the present invention tried to add polyamide elastomers with PA6 as hard segments to polyamide resins, but the low-temperature impact resistance of the obtained material was not significantly improved. The inventors of the present invention further found through research that on the basis of adding polyamide elastomers, benzenesulfonamide plasticizers and silicones were also added, and the obtained material had good low-temperature impact resistance, and no cracks or whitening occurred under the impact of a low-temperature falling ball. The reason may be that benzenesulfonamide plasticizers can effectively promote the dispersion of polyamide elastomers in polyamide resins, and silicones also help the dispersion of polyamide elastomers to a certain extent, thereby effectively exerting the low-temperature impact resistance of polyamide elastomers and significantly improving the low-temperature impact resistance of polyamide materials.

[0017] Surprisingly, the addition of polyamide elastomer with PA6 as the hard segment, benzenesulfonamide plasticizer and silicone can also make the polyamide material have a low noise effect. The reason may be that the benzenesulfonamide plasticizer and polyamide elastomer can simultaneously hydrogen bond with the molecular chain of the polyamide resin (PA6 resin or PA66 resin), change the conformation of the polyamide molecular chain, and destroy part of the crystal region. In addition, the three form physical crosslinks under the action of hydrogen bonds, and then cooperate with silicone to comprehensively improve the loss factor of the material. When the material is subjected to external force, more energy is converted into heat dissipation, which has a good noise reduction effect. Specifically, in the noise assessment of the obtained polyamide material, the measured RPN value is between 1 and 3, indicating that the risk of abnormal noise in the material is relatively low.

[0018] That is, the present invention uses a specific polyamide resin (PA6 resin or PA66 resin) as a base resin, and then combines a benzenesulfonamide plasticizer, silicone and a polyamide elastomer with PA6 as a hard segment to obtain a polyamide material with low noise and good low-temperature impact resistance.

[0019] Generally, the relative viscosity of the polyamide resin is 2.0-3.0.

[0020] Preferably, the relative viscosity of the polyamide resin is 2.4-2.8.

[0021] By regulating the relative viscosity of the polyamide resin within the range of 2.4 to 2.8, the low noise performance of the polyamide material is better.

[0022] The relative viscosity of the polyamide resin of the present invention can be measured according to ISO 307-2007. The solvent selected for the test is concentrated sulfuric acid with a mass concentration of 96%.

[0023] Generally, the polyether segment in the polyamide elastomer is a polyetheramine segment or a polyetherester segment.

[0024] Typically, the Shore hardness of the polyamide elastomer is 25D-65D.

[0025] Preferably, the Shore hardness of the polyamide elastomer is 46D-64D.

[0026] Generally speaking, the higher the hardness of a polyamide elastomer, the higher its hard segment content. When the hardness of the polyamide elastomer is regulated within a higher range (46D to 64D), the hard segment content of the polyamide elastomer is also higher, which can make the obtained polyamide material have better low-noise performance.

[0027] The hardness of the polyamide elastomer of the present invention can be measured according to ISO 868-2003, and the hardness value is measured after 15S of testing.

[0028] Typically, the mass ratio of the polyamide elastomer to the benzenesulfonamide plasticizer is 1:(0.2-0.5).

[0029] Typically, the mass ratio of the polyamide elastomer to silicone is 1:(0.05-0.1).

[0030] Preferably, the glass fiber is at least one of chopped glass fiber or continuous glass fiber.

[0031] Preferably, the benzenesulfonamide plasticizer is at least one of N-butylbenzenesulfonamide, N-ethyl-o-p-toluenesulfonamide or N-(2-hydroxypropyl)benzenesulfonamide.

[0032] Optionally, the silicone includes but is not limited to organopolysiloxane, such as linear polydimethylsiloxane.

[0033] Generally, silicone can be added in the form of masterbatch, and the content of silicone in the masterbatch is generally 30-60 wt%.

[0034] Preferably, the polyamide material further comprises 0.4 to 2 parts of other additives. Without impairing the effects of the present invention, the other additives may include but are not limited to colorants, lubricants, antioxidants, light stabilizers, etc.

[0035] More preferably, the other auxiliary agent is at least one of an antioxidant or a nucleating agent.

[0036] Optionally, the antioxidant includes but is not limited to antioxidant 1010 and / or antioxidant 1098.

[0037] Optionally, the nucleating agent includes but is not limited to talc, montmorillonite or nano calcium carbonate.

[0038] Preferably, the polyamide material comprises the following components in parts by weight:

[0039]

[0040]

[0041] The preparation method of the polyamide material comprises the following steps: mixing the components, melt-extruding, and granulating to obtain the polyamide material.

[0042] Typically, the melting temperature is 225-265°C.

[0043] The use of the above polyamide material in the preparation of automobile door handles, dashboard brackets or drag chains also falls within the protection scope of the present invention.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The invention uses a specific polyamide resin (PA6 resin or PA66 resin) as a base resin, and then mixes a benzenesulfonamide plasticizer, silicone and a polyamide elastomer with PA6 as a hard segment to obtain a polyamide material with low noise and good low-temperature impact resistance. DETAILED DESCRIPTION

[0046] In order to more clearly and completely describe the technical solution of the present invention, the present invention is further described in detail through specific embodiments below. It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention. Various changes can be made within the scope of the rights of the present invention.

[0047] Some of the reagents selected in the embodiments and comparative examples of the present invention are described as follows:

[0048] Polyamide resin 1#: PA6, M2400, relative viscosity 2.4, Xinhui Meida,

[0049] Polyamide resin 2#: PA6, M2800, relative viscosity 2.8, Xinhui Meida,

[0050] Polyamide resin 3#: PA6, M2000, relative viscosity 2.0, Xinhui Meida;

[0051] Polyamide resin 4#: PA66, EP-1107, relative viscosity 2.4, Huafeng;

[0052] Polyamide resin 5#: PA12, WANAMID L3000, relative viscosity 1.4, Wanhua Chemical

[0053] Polyamide elastomer 1#: 4510SA01, PA6 as hard segment, polyether segment as soft segment, hardness 46D, Beijing Xuyang Technology Co., Ltd.;

[0054] Polyamide elastomer 2#: 6510SA01, PA6 as hard segment, polyether segment as soft segment, hardness 64D, Beijing Xuyang Technology Co., Ltd.;

[0055] Polyamide elastomer 3#: 3010SA01, PA6 as hard segment, polyether segment as soft segment, hardness 30D, Beijing Xuyang Technology Co., Ltd.;

[0056] Polyamide elastomer 4#: PA12 is the hard segment, with polyether segments as the soft segment, hardness 40D, Evonik;

[0057] Polyamide elastomer 5#: PA12 is the hard segment, with polyether chain segment as the soft segment, hardness 62D, Evonik;

[0058] Glass fiber 1#: chopped glass fiber, ECS10-3.0-T435TM, Taishan International;

[0059] Glass fiber 2#: continuous glass fiber, ER4305PM-2400, Chongqing International;

[0060] Benzenesulfonamide plasticizer 1#: N-butylbenzenesulfonamide, commercially available;

[0061] Benzenesulfonamide plasticizer 2#: N-(2-hydroxypropyl)benzenesulfonamide, commercially available;

[0062] Other plasticizers: trioctyl trimellitate, commercially available;

[0063] Silicone: MB50-002, Dow Corning; the effective content of silicone is 50 wt%.

[0064] Other lubricants: calcium stearate, commercially available;

[0065] Other additives: antioxidant 1010, commercially available;

[0066] Unless otherwise specified, the components (such as antioxidants) used in the parallel examples and comparative examples are all the same commercially available products.

[0067] The polyamide materials provided in the embodiments and comparative examples of the present invention were tested for performance according to the following test methods:

[0068] (1) Low-temperature drop ball impact performance: According to the standard PV3905-2015, a 2mm square plate of the material is placed in a low-temperature environment of -40℃ for 24 hours, and then immediately dropped with a 500g iron ball and a 400mm drop ball to impact the sample. The cracks and whitening of the sample are observed: if there are no cracks and no whitening, it is considered that the low-temperature impact resistance is good; if there are no cracks and whitening, it is considered that the low-temperature impact resistance is poor; if there are cracks, it is considered that the low-temperature impact resistance is poor.

[0069] (2) Noise assessment: The risk factor (RPN) of abnormal noise is tested according to the standard VDA230-206-2005. The contact area between the sample to be tested and the friction pair is 1250mm 2 , the sliding distance is fixed at 50mm, the sliding speed is 4mm / s, and the load is 10N. Before the test, the sample is conditioned in an environment with a temperature of (23±2)℃ and a relative humidity of (50±5)% for more than 24 hours. RPN is the product of the frequency, severity and detection level of an event. It is called the risk coefficient or risk sequence number. The larger the value, the more serious the potential problem. It is generally believed that when RPN=1~3, the risk of abnormal noise in the material is small, and the material has low-noise performance; when RPN=4~5, the material has a medium risk of abnormal noise; when RPN=6~10, the material has a high risk of abnormal noise; when RPN is 4 or above, the material has poor low-noise performance.

[0070] The polyamide materials of the embodiments of the present invention and the comparative examples are prepared by the following preparation method:

[0071] Weigh each component according to the formula; add the components except glass fiber from the main feeding port of the twin-screw extruder, add the glass fiber from the side feeding port of the twin-screw extruder, and obtain the polyamide material through melt blending and extrusion granulation. The temperature of the twin-screw extruder is 225-265°C.

[0072] Examples 1 to 13

[0073] Examples 1 to 13 provide a series of polyamide materials, whose formulations are shown in Tables 1 and 2.

[0074] Table 1 Formula of Examples 1 to 6 (parts by weight)

[0075]

[0076] Table 2 Formulas of Examples 7 to 13 (parts by weight)

[0077]

[0078] The amount of silicone used in each example has been converted into the amount of pure silicone based on the effective content of the masterbatch.

[0079] Comparative Example 1

[0080] This comparative example provides a polyamide material, and its preparation method and formula are basically the same as those of Example 1, except that: polyamide elastomer 1# is not added.

[0081] Comparative Example 2

[0082] This comparative example provides a polyamide material, whose preparation method and formula are basically the same as those of Example 1, except that polyamide elastomer 1# is replaced by polyamide elastomer 4#.

[0083] Comparative Example 3

[0084] This comparative example provides a polyamide material, and its preparation method and formula are basically the same as those of Example 1, except that polyamide elastomer 1# is replaced by polyamide elastomer 5#.

[0085] Comparative Example 4

[0086] This comparative example provides a polyamide material, whose preparation method and formula are basically the same as those of Example 1, except that: no benzenesulfonamide plasticizer 1# is added.

[0087] Comparative Example 5

[0088] This comparative example provides a polyamide material, whose preparation method and formula are basically the same as those of Example 1, except that the benzenesulfonamide plasticizer 1# is replaced by other plasticizers (trioctyl trimellitate).

[0089] Comparative Example 6

[0090] This comparative example provides a polyamide material, the preparation method and formulation of which are substantially the same as those of Example 1, except that no silicone is added.

[0091] Comparative Example 7

[0092] This comparative example provides a polyamide material, whose preparation method and formula are basically the same as those of Example 1, except that silicone is replaced by other lubricants (calcium stearate).

[0093] Comparative Example 8

[0094] This comparative example provides a polyamide material, and its preparation method and formula are basically the same as those of Example 1, except that polyamide resin 1# is replaced by polyamide resin 5#.

[0095] Comparative Example 9

[0096] This comparative example provides a polyamide material, and its preparation method and formula are basically the same as those of comparative example 3, except that: polyamide resin 1# is replaced by polyamide resin 5#.

[0097] The properties of the polyamide materials of the embodiments and comparative examples were measured according to the above-mentioned test methods. The test results are shown in Table 3.

[0098] Table 3 Polyamide material performance test results of each embodiment and comparative example

[0099] Test Results Low temperature drop ball impact performance RPN Example 1 No cracks and no whitening 1 Example 2 No cracks and no whitening 3 Example 3 No cracks and no whitening 3 Example 4 No cracks and no whitening 2 Example 5 No cracks and no whitening 2 Example 6 No cracks and no whitening 1 Example 7 No cracks and no whitening 1 Example 8 No cracks and no whitening 3 Example 9 No cracks and no whitening 3 Example 10 No cracks and no whitening 1 Embodiment 11 No cracks and no whitening 3 Example 12 No cracks and no whitening 3 Embodiment 13 No cracks and no whitening 1 Comparative Example 1 There are cracks 7 Comparative Example 2 There are cracks 5 Comparative Example 3 There are cracks 5 Comparative Example 4 There are cracks 6 Comparative Example 5 There are cracks 5 Comparative Example 6 No cracks, whitening 5 Comparative Example 7 No cracks and no whitening 4 Comparative Example 8 There are cracks 2 Comparative Example 9 No cracks, whitening 4 .

[0100] From Table 3, we can see that:

[0101] The polyamide materials of Examples 1 to 13 had no cracks or whitening in the low-temperature falling ball impact test, and the RPN values ​​were between 1 and 3, indicating that the polyamide materials of the present invention have low noise and good low-temperature impact resistance.

[0102] Comparative Example 1 does not add polyamide elastomer 1#, and the obtained polyamide material cracks in the low-temperature drop ball impact test, has poor low-temperature impact resistance, and has an RPN value of 7, with a high risk of abnormal noise. The hard segment of the polyamide elastomer added to Comparative Examples 2 and 3 is not suitable, and the obtained polyamide material cracks in the low-temperature drop ball impact test, has poor low-temperature impact resistance, and has an RPN value of 5, with a high risk of abnormal noise. Comparative Example 4 does not add benzenesulfonamide plasticizer, and the obtained polyamide material cracks in the low-temperature drop ball impact test, has poor low-temperature impact resistance, and has an RPN value of 6, with a high risk of abnormal noise. The plasticizer added to Comparative Example 5 is not suitable, and the obtained polyamide material cracks in the low-temperature drop ball impact test, has poor low-temperature impact resistance, and has an RPN value of 5, with a high risk of abnormal noise. Comparative Example 6 does not add silicone, and the obtained polyamide material does not produce cracks in the low-temperature drop ball impact test, but has a whitening phenomenon, poor low-temperature impact resistance, and an RPN value of 5, with a high risk of abnormal noise. In Comparative Example 7, instead of adding silicone, calcium stearate, which is commonly used as a lubricant, is added. The RPN value of the obtained polyamide material is 4, and the risk of abnormal noise is relatively high. The polyamide resin selected in Comparative Example 8 is not suitable, and the obtained polyamide material produces cracks in the low-temperature drop ball impact test, and the low-temperature impact resistance is poor. In Comparative Example 9, the hard segment of the polyamide elastomer and the polyamide resin selected are not suitable. The obtained polyamide material has no cracks in the low-temperature drop ball impact test but has whitening phenomenon, poor low-temperature impact resistance, and an RPN value of 4, and the risk of abnormal noise is relatively high.

[0103] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A low-noise polyamide material, characterized in that: The composition comprises the following components in parts by weight: 35-79 parts of polyamide resin, Polyamide elastomer 4~16 parts, Glass fiber 15~40 parts, 1~5 parts of benzenesulfonamide plasticizer, Silicone 0.4~1 part; The polyamide resin is at least one of PA6 resin or PA66 resin; The polyamide elastomer is a copolymer composed of PA6 as a hard segment and a polyether segment as a soft segment; The relative viscosity of the polyamide resin is 2.0-3.0, and the relative viscosity of the polyamide resin is measured according to ISO 307-2007. The solvent used in the test is concentrated sulfuric acid with a mass concentration of 96%; The Shore hardness of the polyamide elastomer is 25D-65D, and the Shore hardness of the polyamide elastomer is measured according to ISO 868-2003, which is the hardness value after testing for 15S.

2. The polyamide material according to claim 1, characterized in that: The glass fiber is at least one of chopped glass fiber or continuous glass fiber.

3. The polyamide material according to claim 1, characterized in that: The benzenesulfonamide plasticizer is at least one of N-butylbenzenesulfonamide, N-ethyl-o-p-toluenesulfonamide or N-(2-hydroxypropyl)benzenesulfonamide.

4. The polyamide material according to claim 1, characterized in that: The polyamide material also includes 0.4 to 2 parts of other additives.

5. The polyamide material according to claim 4, characterized in that: The other auxiliary agent is at least one of an antioxidant and a nucleating agent.

6. The polyamide material according to claim 1, characterized in that: The polyamide material comprises the following components in parts by weight: 45-65 parts of polyamide resin, Polyamide elastomer 7~12 parts, Glass fiber 20~25 parts, Benzenesulfonamide plasticizer 2~4 parts, Silicone 0.6~0.8 parts.

7. The method for preparing the polyamide material according to any one of claims 1 to 6, characterized in that: The method comprises the following steps: mixing the components, melt-extruding and granulating to obtain the polyamide material.

8. Use of the polyamide material according to any one of claims 1 to 6 in the preparation of automobile door handles, dashboard brackets or drag chains.

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