High-strength nylon particle special for automobile and preparation process thereof

Abstract

The invention discloses high-strength nylon particles special for automobiles and a preparation process of the high-strength nylon particles. The nylon particles comprise a nylon matrix material, activated carbon fiber reinforced filler, a flexibilizer, a heat stabilizer, an antioxidant and a lubricant. Carbon fibers are activated through specific cleaning, oxidation, coupling and other steps to improve the dispersity and compatibility of the carbon fibers in a nylon matrix, so that the tensile strength, bending strength and impact strength of the material are remarkably improved. Meanwhile, due to the addition of the copper salt heat stabilizer and the hindered amine antioxidant, the material is endowed with excellent heat resistance and ageing resistance. The material has high strength, good toughness, excellent thermal stability and aging resistance, is especially suitable for high-performance light-weight parts in the automobile industry, and meets the high requirements of the automobile industry on material strength, durability and processability.

Description

Technical Field

[0001] The invention relates to the field of preparation of nylon particles, and more specifically to high-strength nylon particles for automobiles and a preparation process thereof. Background Art

[0002] With the development of the automobile industry, the market demand for the performance of automobile parts is increasing, especially the demand for lightweight and high-strength materials is becoming more and more prominent. Lightweighting of automobile parts can not only improve fuel efficiency and reduce carbon dioxide emissions, but also improve the handling and safety of vehicles. Therefore, the development of materials with high strength and lightweight characteristics has become one of the important directions in the current automotive materials field. Nylon (PA) materials have gradually become a substitute for metal materials in automotive parts due to their good mechanical strength, wear resistance and chemical corrosion resistance. However, traditional nylon materials often have problems such as insufficient strength and poor durability under high temperature and high load conditions, which limits their wider application in automotive structural parts. In order to improve the strength and durability of nylon, reinforcing fillers are usually added to the nylon matrix to improve its mechanical properties.

[0003] Carbon fiber reinforced nylon materials not only have high tensile strength and rigidity, but also have excellent durability under high temperature and complex environments, which can meet the high performance requirements of the automotive industry. However, the interface compatibility between the carbon fiber surface and the nylon matrix material is poor, so further optimization is needed. Summary of the invention

[0004] In order to solve the deficiencies of the prior art, the present invention provides a high-strength nylon particle for automobiles and a preparation process thereof, and the specific scheme is as follows:

[0005] A high-strength nylon particle for automobiles, the nylon particle comprising the following components, calculated by total weight percentage:

[0006] Nylon matrix material: 50-60%;

[0007] Modified carbon fiber reinforced filler: 5-15%, the average diameter of the carbon fiber is 5-10 μm, and the length is 100-200 μm;

[0008] Toughening agent: 5-10%;

[0009] Heat stabilizer: selected from copper salt stabilizers, accounting for 0.5-1.5% of the total weight;

[0010] Antioxidant: selected from hindered amine antioxidants, accounting for 0.2-0.5% of the total weight;

[0011] Lubricant: selected from zinc stearate, accounting for 0.1-0.5% of the total weight.

[0012] Furthermore, the preparation method of the modified carbon fiber reinforced material comprises the following steps:

[0013] S1: ultrasonically clean the carbon fiber in an ethanol solution for 10 to 15 minutes to remove surface oil and impurities, and then rinse with deionized water for 3 to 5 times;

[0014] S2: placing the cleaned carbon fiber in an oxidation solution for soaking reaction, wherein the oxidation reaction temperature is controlled at 60 to 80° C. and the time is 30 to 60 minutes;

[0015] S3: placing the oxidized carbon fiber in dilute ammonia water to neutralize the residual acidic substances for 10 to 15 minutes; then repeatedly rinsing with deionized water until neutral, and finally drying with hot air until the moisture content of the carbon fiber is less than 0.5%;

[0016] S4: Soak the dried carbon fiber in a coupling agent solution for 20 to 30 minutes at a temperature of 25 to 35°C. Take out the treated carbon fiber and dry it at 80 to 100°C for 2 to 3 hours.

[0017] Furthermore, the oxidizing solution in S2 is a mixture of 98% sulfuric acid and 30% hydrogen peroxide in a volume ratio of 3:1.

[0018] Furthermore, the concentration of the dilute ammonia water is 0.5%.

[0019] Furthermore, the molecular weight of the nylon matrix material is 20,000 to 30,000.

[0020] A preparation process of high-strength nylon particles for automobiles, the preparation process comprising the following steps:

[0021] S1: prepare nylon matrix material, carbon fiber, toughening agent, thermal stabilizer, antioxidant and lubricant;

[0022] S2: Use a twin-screw extruder for mixing; pre-mix the nylon matrix material and the carbon fiber at a speed of 100-150 rpm for 5-10 minutes to ensure that the carbon fiber is evenly dispersed in the matrix; gradually add the toughening agent, heat stabilizer, antioxidant and lubricant, and continue mixing for 3-5 minutes after each addition to ensure that the components are evenly dispersed;

[0023] S3: Extrusion granulation: The temperature of each temperature zone of the twin-screw extruder is set as follows: feed section temperature: 220-230°C; melting section temperature: 240-250°C; homogenization section temperature: 250-260°C; die section temperature: 260-270°C; the extruder speed is set to 200-300rpm to ensure sufficient mixing of the materials and avoid degradation of the carbon fiber; the molten material after extrusion is cooled in a water bath at 20-25°C and cut into nylon particles with a diameter of 2-3mm;

[0024] S4: After pelletizing, the nylon particles are dried in a hot air circulation oven at 80 to 100° C. for 6 to 8 hours to remove moisture.

[0025] Furthermore, the screw diameter of the twin-screw extruder in S2 is 30-50 mm, and the aspect ratio is 40:1.

[0026] Beneficial effects:

[0027] The present invention significantly improves the strength of nylon materials by adding activated carbon fiber reinforced fillers to the nylon matrix. The application of activated carbon fibers not only effectively improves the tensile strength and flexural strength, making the material significantly superior to traditional nylon in key mechanical properties, but also enhances the impact toughness, so that the material has a higher resistance to damage when subjected to external impact. At the same time, the activation treatment improves the compatibility of carbon fibers with the nylon matrix, ensures the uniform dispersion and stable combination of the reinforcing fillers, so that the material maintains excellent heat resistance under high temperature conditions. In addition, the addition of hindered amine antioxidants further enhances the anti-aging properties of the material and prolongs its service life. This high-strength, high-temperature resistant and anti-aging nylon material is particularly suitable for lightweight and high-strength component applications in the automotive industry, and provides important material support for meeting the high-performance requirements of the automotive industry. DETAILED DESCRIPTION

[0028] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with examples. The examples are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0029] Embodiment 1:

[0030] A preparation process of high-strength nylon particles for automobiles:

[0031] Group distribution ratio:

[0032] Nylon matrix material (nylon 6): 55%, molecular weight 25,000;

[0033] Modified carbon fiber: 10%, average diameter 7μm, length 150μm;

[0034] Toughening agent (EPDM): 8%;

[0035] Heat stabilizer (copper salt): 1%;

[0036] Antioxidant (hindered amines): 0.3%;

[0037] Lubricant (zinc stearate): 0.2%.

[0038] Preparation method:

[0039] S1: Carbon fiber activation treatment:

[0040] The carbon fibers were ultrasonically cleaned with ethanol solution for 15 minutes to remove surface impurities, and then rinsed with deionized water for 3 times.

[0041] The cleaned carbon fiber was placed in an oxidation solution (98% sulfuric acid and 30% hydrogen peroxide, volume ratio 3:1) and reacted at 70° C. for 45 minutes.

[0042] Neutralize with 0.5% dilute ammonia water, soak for 12 minutes, rinse with deionized water until neutral, and then dry with hot air until the moisture content is less than 0.5%.

[0043] The sample was immersed in a 1.5% 3-aminopropyltriethoxysilane solution at 30° C. for 25 minutes, then taken out and dried at 80° C. for 2 hours.

[0044] S2: Twin screw extruder mixing:

[0045] Using a twin-screw extruder with a screw diameter of 40 mm and an aspect ratio of 40:1, the nylon matrix material and the activated carbon fiber were premixed at a speed of 120 rpm for 8 minutes.

[0046] Toughener, heat stabilizer, antioxidant and lubricant were added in sequence with mixing for 4 minutes after each addition.

[0047] S3: Extrusion granulation:

[0048] Set temperature zones: feed section 220°C, melting section 245°C, homogenization section 255°C, die section 265°C, extruder speed 250rpm.

[0049] The extrudate was cooled in a 20°C water bath and cut into 2 mm particles.

[0050] S4: Drying:

[0051] Dry in a hot air circulation oven at 90°C for 6 hours.

[0052] Embodiment 2:

[0053] A preparation process of high-strength nylon particles for automobiles:

[0054] Group distribution ratio:

[0055] Nylon matrix material (nylon 66): 53%, molecular weight 22,000;

[0056] Modified carbon fiber: 12%, average diameter 6μm, length 180μm;

[0057] Toughening agent (EPDM): 6%;

[0058] Heat stabilizer (copper salt): 1.2%;

[0059] Antioxidant (hindered amines): 0.4%;

[0060] Lubricant (zinc stearate): 0.3%.

[0061] Preparation method:

[0062] S1: Carbon fiber activation treatment:

[0063] Ultrasonic cleaning was performed using ethanol for 10 min and rinsed five times with deionized water.

[0064] The carbon fibers were placed in an oxidizing solution and reacted at 75°C for 50 minutes.

[0065] Neutralize with 0.5% dilute ammonia water for 15 minutes, wash with water until neutral, and then dry until the moisture content is less than 0.5%.

[0066] 1% coupling agent solution (3-aminopropyltriethoxysilane) was soaked for 20 minutes, and the drying temperature was 85°C for 2.5 hours.

[0067] S2: Twin screw extruder mixing:

[0068] Using an extruder with a screw diameter of 30 mm, nylon and carbon fiber were premixed at a rotation speed of 130 rpm for 5 minutes.

[0069] Toughener, heat stabilizer, antioxidant and lubricant were added in batches, with a single mixing time of 3 minutes.

[0070] S3: Extrusion granulation:

[0071] Temperature zone settings: feeding section 225°C, melting section 250°C, homogenizing section 255°C, die section 270°C, extruder speed 300rpm.

[0072] The water bath temperature was cooled to 22°C and the pellets were cut into 3 mm particles.

[0073] S4: Drying:

[0074] Dry in a hot air circulation oven at 100°C for 7 hours.

[0075] Embodiment 3:

[0076] A preparation process of high-strength nylon particles for automobiles:

[0077] Group distribution ratio:

[0078] Nylon matrix material (nylon 6): 57%, molecular weight 28,000;

[0079] Modified carbon fiber: 8%, average diameter 8μm, length 120μm;

[0080] Toughening agent (EPDM): 7%;

[0081] Heat stabilizer (copper salt): 0.8%;

[0082] Antioxidant (hindered amines): 0.2%;

[0083] Lubricant (zinc stearate): 0.3%.

[0084] Preparation method:

[0085] S1: Carbon fiber activation treatment:

[0086] The carbon fibers were ultrasonically cleaned with ethanol for 15 min and rinsed with deionized water four times.

[0087] The oxidation solution treatment temperature was set at 60°C and the reaction time was 30 minutes.

[0088] Neutralize with 0.5% diluted ammonia water for 10 minutes, rinse until neutral and then dry.

[0089] Use 2% coupling agent solution to soak at 35°C for 30 minutes, dry at 90°C, and dry for 3 hours.

[0090] S2: Twin screw extruder mixing:

[0091] Using a twin-screw extruder with a diameter of 50 mm, nylon and carbon fibers were premixed at 100 rpm for 10 minutes.

[0092] Add remaining ingredients in steps, mixing for 5 minutes each step.

[0093] S3: Extrusion granulation:

[0094] Extrusion temperature settings: feed section 220°C, melting section 240°C, homogenization section 250°C, die section 265°C, and the rotation speed is set to 200rpm.

[0095] The cooling water bath temperature was 23°C and the pellets were cut into 2.5 mm particles.

[0096] S4: Drying:

[0097] Hot air drying at 85°C for 6 hours.

[0098] Comparative example: Nylon material without carbon fiber reinforcement

[0099] The nylon materials of Examples 1 to 3 and the comparative example were tested for performance, and the test data are as follows:

[0100]

[0101] It can be seen from the above table that the improved nylon material of this embodiment has been significantly improved in strength.

[0102] As a further improvement, the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A high-strength nylon particle for automobiles, characterized in that: The nylon particles comprise the following components, in terms of total weight percentage: Nylon matrix material: 50-60%; Modified carbon fiber reinforced filler: 5-15%, the average diameter of the carbon fiber is 5-10 μm, and the length is 100-200 μm; Toughening agent: 5-10%; Heat stabilizer: selected from copper salt stabilizers, accounting for 0.5-1.5% of the total weight; Antioxidant: selected from hindered amine antioxidants, accounting for 0.2-0.5% of the total weight; Lubricant: selected from zinc stearate, accounting for 0.1-0.5% of the total weight.

2. The high-strength nylon particles for automobiles according to claim 1, characterized in that: The preparation method of the modified carbon fiber reinforced material comprises the following steps: S1: ultrasonically clean the carbon fiber in an ethanol solution for 10 to 15 minutes to remove surface oil and impurities, and then rinse with deionized water for 3 to 5 times; S2: placing the cleaned carbon fiber in an oxidation solution for soaking reaction, wherein the oxidation reaction temperature is controlled at 60 to 80° C. and the time is 30 to 60 minutes; S3: placing the oxidized carbon fiber in dilute ammonia water to neutralize the residual acidic substances for 10 to 15 minutes; then repeatedly rinsing with deionized water until neutral, and finally drying with hot air until the moisture content of the carbon fiber is less than 0.5%; S4: Soak the dried carbon fiber in a coupling agent solution for 20 to 30 minutes at a temperature of 25 to 35°C. Take out the treated carbon fiber and dry it at 80 to 100°C for 2 to 3 hours.

3. The high-strength nylon particles for automobiles according to claim 2, characterized in that: The oxidizing solution in S2 is a mixture of 98% sulfuric acid and 30% hydrogen peroxide in a volume ratio of 3:

1.

4. The high-strength nylon particles for automobiles according to claim 2, characterized in that: The concentration of dilute ammonia water is 0.5%.

5. The high-strength nylon particles for automobiles according to claim 1, characterized in that: The molecular weight of the nylon matrix material is 20,000 to 30,000.

6. A process for preparing high-strength nylon particles for automobiles, characterized in that: The preparation process comprises the following steps: S1: prepare nylon matrix material, carbon fiber, toughening agent, thermal stabilizer, antioxidant and lubricant; S2: Use a twin-screw extruder for mixing; pre-mix the nylon matrix material and the carbon fiber at a speed of 100-150 rpm for 5-10 minutes to ensure that the carbon fiber is evenly dispersed in the matrix; gradually add the toughening agent, heat stabilizer, antioxidant and lubricant, and continue mixing for 3-5 minutes after each addition to ensure that the components are evenly dispersed; S3: Extrusion granulation: The temperature of each temperature zone of the twin-screw extruder is set as follows: feed section temperature: 220-230°C; melting section temperature: 240-250°C; homogenization section temperature: 250-260°C; die section temperature: 260-270°C; the extruder speed is set to 200-300rpm to ensure sufficient mixing of the materials and avoid degradation of the carbon fiber; the molten material after extrusion is cooled in a water bath at 20-25°C and cut into nylon particles with a diameter of 2-3mm; S4: After pelletizing, the nylon particles are dried in a hot air circulation oven at 80 to 100° C. for 6 to 8 hours to remove moisture.

7. The process for preparing high-strength nylon particles for automobiles according to claim 6, characterized in that: The twin-screw extruder in S2 has a screw diameter of 30-50 mm and an aspect ratio of 40:1.

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