Nylon composite material and preparation method thereof

Abstract

Aiming at the problem of high carbon emission of the existing nylon material for vehicles, the invention provides the nylon composite material and the preparation method thereof, and the nylon composite material comprises the following components in parts by weight: 50-70 parts of low-carbon polyamide resin, 1-20 parts of polypropylene, 10-30 parts of glass fiber, 0.1-6 parts of a coupling agent and 0.3-18 parts of a functional additive.

Description

Technical Field

[0001] The invention belongs to the technical field of nylon materials, and particularly relates to a nylon composite material and a preparation method thereof. Background Art

[0002] Nylon materials are widely used in the automotive field, such as wiper transmission, radiator fan, rearview mirror bracket, tie rod, cooling water pipe / joint, buckle, armrest hinge, ceiling armrest, engine upper guard plate, refueling exhaust bellows, fuel vapor pipe, brake vacuum hose, shift operating mechanism, battery radiator, sunroof anti-pinch motor and other parts, which can replace metal to achieve better lightweight and anti-corrosion effects while meeting high-performance requirements. In recent years, in the process of low-carbon material development and application, the carbon reduction work of nylon materials with high carbon emissions and high application ratio is particularly urgent, and the development of low-carbon nylon materials is also more important.

[0003] The amide group of nylon is a highly polar group, which is easily affected by environmental factors such as temperature and humidity, resulting in physical / chemical aging, which reduces the safety and life of the material and may even cause serious accidents. Nylon materials are often used in cooling systems, such as water chambers, cooling pipes, pipe joints and valves. These parts are in contact with coolant for a long time, which will absorb moisture and hydrolyze, causing the material performance to deteriorate. Therefore, most of the nylon materials used in automobiles are hydrolysis-resistant nylon materials PA66-GF30, but their carbon emissions are high, which reduces the environmental protection attributes of the car. Summary of the invention

[0004] In view of the problem of high carbon emission of existing nylon materials for automobiles, the present invention provides a nylon composite material and a preparation method thereof.

[0005] The technical solution adopted by the present invention to solve the above technical problems is as follows:

[0006] In one aspect, the present invention provides a nylon composite material, comprising the following components by weight: 50-70 parts of low-carbon polyamide resin, 1-20 parts of polypropylene, 10-30 parts of glass fiber, 0.1-6 parts of coupling agent and 0.3-18 parts of functional additive.

[0007] Optionally, the following components by weight are included: 50-55 parts of low-carbon polyamide resin, 10-20 parts of polypropylene, 10-30 parts of glass fiber, 0.1-6 parts of coupling agent and 0.3-18 parts of functional additive.

[0008] Optionally, the low carbon polyamide resin includes at least one of recycled nylon 66 and bio-based nylon 56.

[0009] Optionally, the glass fiber includes a glass fiber with a silane-based sizing agent coated on the surface, and the glass fiber has a diameter of 6-15 μm and a short cut length of 3-5 mm.

[0010] Optionally, the coupling agent includes one or more of a silane coupling agent, a titanate coupling agent, and an aluminate coupling agent.

[0011] Optionally, the functional additive includes one or more of a compatibilizer, an anti-hydrolysis agent and a thermal stabilizer.

[0012] Optionally, based on the weight of the nylon composite material, the functional additives include 0.1-6 parts of a compatibilizer, 0.1-6 parts of a hydrolysis resistance agent and 0.1-6 parts of a heat stabilizer.

[0013] Optionally, the compatibilizer is a dual-monomer grafted solubilizer, and the dual-monomer grafted solubilizer includes one or more of polypropylene grafted maleic anhydride and triallyl isocyanurate, polypropylene grafted maleic anhydride and diallyl phthalate, and polypropylene grafted maleic anhydride and vinyl acetate.

[0014] Optionally, the anti-hydrolysis agent includes an amine anti-hydrolysis agent, and the amine anti-hydrolysis agent includes polycarbodiimide;

[0015] The thermal stabilizer includes at least one of antioxidant 1098 and antioxidant 168.

[0016] On the other hand, the present invention provides a method for preparing a nylon composite material as described in any one of the above items, characterized in that it comprises the following steps: mixing a low-carbon polyamide resin, polypropylene, glass fiber, a coupling agent and a functional additive at a rotation speed of 500 to 1800 rpm, and melt-extruding, granulating and drying the mixed raw materials at 200-300°C to obtain a nylon composite material.

[0017] In the present invention, polypropylene is added to the low-carbon polyamide resin, which effectively improves the toughness, hydrolysis resistance and impact performance of the nylon composite material on the basis of enhancing the low-carbon properties of the material and fully reducing the carbon emissions of the material. By adding glass fiber and coupling agent, the cross-sectional wrapping force and bonding force of the low-carbon polyamide resin and the glass fiber are improved, so that the nylon composite material has both high strength and toughness, which can meet the physical property requirements of key parts such as automobile cooling systems. DETAILED DESCRIPTION

[0018] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. 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.

[0019] An embodiment of the present invention provides a nylon composite material, comprising the following weight components: 50-70 parts of low-carbon polyamide resin, 1-20 parts of polypropylene, 10-30 parts of glass fiber, 0.1-6 parts of coupling agent and 0.3-18 parts of functional additive. Specifically, polypropylene includes but is not limited to recycled polypropylene material.

[0020] In the present invention, polypropylene is added to the low-carbon polyamide resin, which effectively improves the toughness, hydrolysis resistance and impact performance of the nylon composite material on the basis of enhancing the low-carbon properties of the material and fully reducing the carbon emissions of the material. By adding glass fiber and coupling agent, the cross-sectional wrapping force and bonding force of the low-carbon polyamide resin and the glass fiber are improved, so that the nylon composite material has both high strength and toughness, which can meet the physical property requirements of key parts such as automobile cooling systems.

[0021] Furthermore, the mass ratio of the low carbon polyamide resin to the polypropylene is 2.45-5.9.

[0022] In a preferred embodiment, the composition comprises the following components by weight: 50-55 parts of low carbon polyamide resin, 10-20 parts of polypropylene, 10-30 parts of glass fiber, 0.1-6 parts of coupling agent and 0.3-18 parts of functional additive.

[0023] In some embodiments, the low-carbon polyamide resin includes at least one of recycled nylon 66 and bio-based nylon 56. By using recycled nylon 66 and bio-based nylon 56 to alloy with polypropylene, instead of petrochemical raw materials, the carbon emissions of nylon composite materials are effectively reduced.

[0024] Specifically, the selected recycled nylon 66 and bio-based nylon 56 have a balanced moisture content of 3.2%-3.4% and a density of 1.13-1.15 g / cm 3 , tensile strength is 75-80MPa, flexural modulus is 2800-3000MPa, and cantilever beam notched impact strength is 3.0-3.5KJ / m 2 .

[0025] The density of the recycled polypropylene selected is 0.9-0.95g / cm 3 , tensile strength is 15-20MPa, flexural modulus is 800-900MPa, cantilever beam notched impact strength is 25-30KJ / m 2 When recycled nylon 66, bio-based nylon 56 and polypropylene that are not within this performance range are selected, the toughness of the resulting nylon composite material is lower than that of the nylon composite material prepared from raw materials with performance within this range.

[0026] In some embodiments, the glass fiber includes a glass fiber with a silane-based sizing agent coated on the surface, the glass fiber has a diameter of 6-15 μm and a short cut length of 3-5 mm. By coating the silane-based sizing agent on the surface of the glass fiber to prevent the glass fiber from hydrolyzing, the physical properties of the nylon composite material are improved.

[0027] In some embodiments, the coupling agent includes one or more of a silane coupling agent, a titanate coupling agent, and an aluminate coupling agent.

[0028] In some embodiments, the functional additives include one or more of a compatibilizer, a hydrolysis resistant agent, and a thermal stabilizer. By adding a compatibilizer and a hydrolysis resistant agent, on the one hand, a special chemical structure interface that penetrates each other can be formed at the interface between the low-carbon polyamide resin and the polypropylene phase, so that the two phases at the interface are smoothly over-fused to effectively reduce stress transmission, improve material properties, form a protective layer for the amide group, and structurally isolate from water or alcohols to improve hydrolysis resistance. On the other hand, it can enhance the bonding strength between the low-carbon polyamide resin and the glass fiber wrapping surface, making the material more resistant to erosion by polar groups.

[0029] In addition, recycled nylon 66, bio-based nylon 56 and recycled polypropylene inevitably contain chain-breaking groups, which have a great influence on the performance of nylon composite materials. The addition of anti-hydrolysis agents can reduce water absorption and improve hydrolysis resistance through grafting copolymerization and polarity enhancement. At the same time, it can react with chain-breaking groups or degraded carboxylic acids in the recycled materials to inhibit the hydrolysis reaction.

[0030] In some embodiments, based on the weight of the nylon composite material, the functional additives include 0.1-6 parts of a compatibilizer, 0.1-6 parts of a hydrolysis resistance agent, and 0.1-6 parts of a heat stabilizer.

[0031] In some embodiments, the compatibilizer is a dual-monomer grafted solubilizer, and the dual-monomer grafted solubilizer includes one or more of polypropylene grafted maleic anhydride and triallyl isocyanurate, polypropylene grafted maleic anhydride and diallyl phthalate, and polypropylene grafted maleic anhydride and vinyl acetate.

[0032] In some embodiments, the anti-hydrolysis agent includes an amine anti-hydrolysis agent, and the amine anti-hydrolysis agent includes polycarbodiimide.

[0033] The thermal stabilizer includes at least one of antioxidant 1098 and antioxidant 168.

[0034] On the other hand, an embodiment of the present invention provides a method for preparing the nylon composite material described in any one of the embodiments, comprising the following steps: mixing a low-carbon polyamide resin, polypropylene, glass fiber, a coupling agent and a functional additive at a rotation speed of 500 to 1800 rpm for 3 to 5 minutes, and melt-extruding, granulating and drying the mixed raw materials at 200 to 300°C to obtain a nylon composite material.

[0035] Specifically, the mixed raw materials are put into a twin-screw extruder for extrusion granulation, the screw speed is 120-320 rpm, the temperature of each section of the screw is: zone 1 220-255°C, zone 2 235-265°C, zone 3 225-250°C, zone 4 215-260°C, the residence time of the entire extrusion process is 1-2 minutes, and the pressure is 12-20 MPa.

[0036] The present invention is further described below by way of examples.

[0037] Examples 1-5 and Comparative Examples 1-7 were prepared using the weight portions in Table 1. The low-carbon polyamide resin was regenerated nylon 66 and / or bio-based nylon 56, the glass fiber was a glass fiber coated with a silane-based sizing agent, the silane coupling agent was KH560, the compatibilizer was polypropylene grafted maleic anhydride and triallyl isocyanurate, the hydrolysis resistance agent was polycarbodiimide, and the heat stabilizer was antioxidant 168.

[0038] Table 1

[0039]

[0040]

[0041] Performance Testing

[0042] The nylon composite materials prepared in Examples 1-5 and Comparative Examples 1-7 were subjected to performance tests.

[0043] Specific test method: Place the nylon composite material in a blast drying oven at 100°C for 2 to 3 hours, and then inject the dried pellets into the injection molding machine to prepare samples. The equilibrium moisture content is carried out in accordance with GB / T 36790. The tensile properties are carried out in accordance with ISO 527, the sample size is 170×10×4mm dumbbell-shaped specimen, and the tensile speed is 50mm / min; the bending performance test is carried out in accordance with ISO 178, the sample size is 80×10×4mm, the bending speed is 2mm / min, and the span is 64mm; the cantilever beam notch impact strength is carried out in accordance with ISO 180, the sample size is 80×10×4mm, and the notch adopts the standard medium A type.

[0044] The test results obtained are entered in Table 2.

[0045] Table 2

[0046]

[0047]

[0048] By comparing Examples 1, 2, 4 and Comparative Examples 1 and 2, it can be seen that the addition of polypropylene can effectively improve the hydrolysis resistance of the material and reduce the water absorption rate of the material, while the toughness of the material is improved, and the rigidity-toughness balance is effectively achieved. It can be seen from Examples 1, 4 and 5 that by adjusting the content of low-carbon polyamide resin, recycled polypropylene resin and glass fiber, the equilibrium moisture content, tensile strength and flexural modulus of the nylon composite material can be adjusted.

[0049] From the comparison between Example 1, Example 3 and Comparative Example 6, it can be seen that the addition of the anti-hydrolysis agent can improve the hydrolysis resistance of the material.

[0050] From the comparison between Example 1, Example 6, Comparative Example 3 and Comparative Example 4, it can be seen that the increase of glass fiber content can effectively improve the strength and rigidity of the material.

[0051] In Comparative Example 5 and Example 1, the addition of the compatibilizer can effectively improve the toughness and hydrolysis resistance of the material.

[0052] By comparing Comparative Example 7 with Example 1, it is found that the silane coupling agent can effectively improve the strength and hydrolysis resistance of the material.

[0053] From the above test results, it can be seen that after adding the compatibilizer and the anti-hydrolysis agent, the hydrolysis resistance of the embodiment is greatly improved, and the surface state of the material after hydrolysis is good without defects such as cracks, and the equilibrium moisture content is also greatly reduced.

[0054] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. 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 present invention.

Claims

1. A nylon composite material, characterized in that: The invention comprises the following components by weight: 50-70 parts of low-carbon polyamide resin, 1-20 parts of polypropylene, 10-30 parts of glass fiber, 0.1-6 parts of coupling agent and 0.3-18 parts of functional additive.

2. The nylon composite material according to claim 1, characterized in that: The invention comprises the following components by weight: 50-55 parts of low-carbon polyamide resin, 10-20 parts of polypropylene, 10-30 parts of glass fiber, 0.1-6 parts of coupling agent and 0.3-18 parts of functional additive.

3. The nylon composite material according to claim 1, characterized in that: The low-carbon polyamide resin includes at least one of recycled nylon 66 and bio-based nylon 56.

4. The nylon composite material according to claim 1, characterized in that: The glass fiber comprises a glass fiber with a silane-based sizing agent coated on the surface. The glass fiber has a diameter of 6-15 μm and a short cut length of 3-5 mm.

5. The nylon composite material according to claim 1, characterized in that: The coupling agent includes one or more of a silane coupling agent, a titanate coupling agent, and an aluminate coupling agent.

6. The nylon composite material according to claim 1, characterized in that: The functional additives include one or more of a compatibilizer, an anti-hydrolysis agent and a thermal stabilizer.

7. The nylon composite material according to claim 6, characterized in that: Based on the weight of the nylon composite material, the functional additives include 0.1-6 parts of a compatibilizer, 0.1-6 parts of a hydrolysis resistance agent and 0.1-6 parts of a heat stabilizer.

8. The nylon composite material according to claim 6, characterized in that: The compatibilizer is a dual-monomer grafted solubilizer, which includes one or more of polypropylene grafted maleic anhydride and triallyl isocyanurate, polypropylene grafted maleic anhydride and diallyl phthalate, and polypropylene grafted maleic anhydride and vinyl acetate.

9. The nylon composite material according to claim 6, characterized in that: The anti-hydrolysis agent includes an amine anti-hydrolysis agent, and the amine anti-hydrolysis agent includes polycarbodiimide; The thermal stabilizer includes at least one of antioxidant 1098 and antioxidant 168.

10. A method for preparing a nylon composite material according to any one of claims 1 to 9, characterized in that: The following steps are involved: The low-carbon polyamide resin, polypropylene, glass fiber, coupling agent and functional additive are mixed at a rotation speed of 500-1800 rpm, and the mixed raw materials are melt-extruded, granulated and dried at 200-300° C. to obtain a nylon composite material.

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