High-strength wear-resistant polyamide material and preparation method thereof

Abstract

The invention relates to a high-strength wear-resistant polyamide material and a preparation method thereof, and belongs to the technical field of polyamide materials. Comprising the following raw materials in parts by weight: 65-80 parts of a polyamide matrix material, 0.5-1 part of a lubricating dispersant, 10-15 parts of wear-resistant master batches, 5-8 parts of modified silica sol, 10-15 parts of modified glass fibers and 0.2-0.5 part of an antioxidant, according to the invention, the chemically-bonded wear-resistant agent is added into the polyamide matrix material to combine self-lubrication and high hardness, then the modified silica sol and the modified glass fiber are added as fillers to synergistically improve the wear resistance of polyamide, and the polyamide material with high strength and good wear resistance is obtained through combined action with other components.

Description

Technical Field

[0001] The invention belongs to the technical field of polyamide materials and relates to a high-strength wear-resistant polyamide material and a preparation method thereof. Background Art

[0002] As a high-performance engineering plastic, polyamide is widely used in automotive manufacturing, mechanical engineering, electronics, aerospace, and other fields due to its excellent mechanical strength, heat resistance, and chemical stability. However, the limitations of traditional polyamide materials under extreme operating conditions (such as high loads, high-speed friction, and high-temperature environments) are becoming increasingly prominent. In particular, insufficient wear resistance can lead to premature component failure, severely restricting their potential for application in high-end equipment and precision instruments.

[0003] At present, the improvement of wear resistance of polyamide materials mainly relies on the addition of inorganic fillers or solid lubricants. Although such methods can improve wear resistance to a certain extent, the introduction of excessive fillers can easily lead to a decrease in material toughness and the risk of brittle fracture; or lead to poor interfacial compatibility, accelerating the propagation of microcracks during wear; and traditional blending modification processes require strict control of filler dispersion and processing temperature, otherwise it is easy to cause agglomeration or thermal degradation, resulting in poor product uniformity and low yield.

[0004] Therefore, it is necessary to develop a polyamide material that has high strength, long-term wear resistance and process friendliness. Summary of the Invention

[0005] The purpose of the present invention is to provide a high-strength and wear-resistant polyamide material and a preparation method thereof. The polyamide material prepared by the present invention has the characteristics of high strength and good wear resistance.

[0006] The purpose of the present invention can be achieved through the following technical solutions: A high-strength wear-resistant polyamide material comprises the following raw materials in parts by weight: 65-80 parts of a polyamide matrix material, 0.5-1 part of a lubricating dispersant, 10-15 parts of a wear-resistant masterbatch, 10-15 parts of modified glass fiber, and 0.2-0.5 part of an antioxidant, wherein the modified glass fiber is treated with cerium sulfate and a silane coupling agent; The preparation process of the wear-resistant masterbatch is as follows: In parts by weight, 45 to 60 parts of high-density polyethylene, 10 to 20 parts of a wear-resistant agent, 10 to 15 parts of zirconium oxide, 10 to 15 parts of a compatibilizer, and 1 to 3 parts of a lubricant are mixed, stirred at a speed of 1000 r / min for 60 to 90 minutes in a high-speed mixer, and then sheared, plasticized, and granulated at 160 to 190° C. through a twin-screw extruder to prepare the wear-resistant masterbatch, wherein the wear-resistant agent is flake graphite and nano-boron nitride that have been processed; The preparation process of modified silica sol is as follows: In parts by weight, 3 to 5 parts of nano-silica sol and 1 to 2 parts of hydroxyethyl cellulose are added to 5 to 8 parts of Tris-HCl buffer solution, and then 2 to 3 parts of 3 to 5% by weight zirconium nitrate solution and 0.3 to 0.5 parts of citric acid are added, and the mixture is stirred to obtain a modified silica sol.

[0007] As a preferred technical solution of the present invention, the preparation process of the modified glass fiber is as follows: S2.1. In parts by weight, 5 to 10 parts of glass fiber and 2 to 4 parts of a dispersant were added to 75 to 100 parts of deionized water, and stirred to obtain a mixture A. The mixture was heated to 80 to 90°C, and the pH of the mixture A was adjusted to 8 to 9 with sodium hydroxide. 5 to 10 parts of cerium sulfate were added, and the mixture was stirred and aged for 1 to 2 hours. Sodium hydroxide was further added to adjust the pH of the mixture A to 8 to 10, and the temperature was maintained for aging for 1 to 3 hours. The mixture was filtered, washed, and dried to obtain a solid B. S2.2, sintering solid B at 400-600°C for 3-5 hours to obtain cerium oxide-coated glass fiber; S2.3. Mix the silane coupling agent KH550 with an ethanol-water solution in a volume ratio of 90:10 to obtain a KH550 solution with a mass fraction of 10-15%, adjust the pH to 6 with acetic acid, stir evenly, add the cerium oxide-coated glass fiber, continue stirring for 4-7 hours, filter, and vacuum dry to obtain the modified glass fiber.

[0008] As a preferred technical solution of the present invention, the preparation process of the wear-resistant agent is as follows: S3.1. Mix hydrogen peroxide, potassium permanganate, 30% concentrated sulfuric acid, and flake graphite in a mass ratio of 3:8:150:100, stir at 60-80°C for 8-12 h, filter, wash with deionized water, and vacuum dry at 80°C for 24 h to obtain solid C. S3.2. Soak the nano-boron nitride in a 30% by mass nitric acid solution for 5-10 minutes, filter, rinse with water, and then add the nano-boron nitride and hydroxypropanol to ethanol. Stir for 5-8 hours, filter, and wash with water to obtain solid D, wherein the mass ratio of hydroxypropanol to nano-boron nitride is 1:10. S3.3. Stir solid C and solid D in an acid solution at a mass ratio of 1:(5-8) for 5-7 hours to obtain the wear-resistant agent.

[0009] As a preferred technical solution of the present invention, the lubricating dispersant is one or more of pentaerythritol stearate, ethylene acrylic acid copolymer and polydimethylsiloxane.

[0010] As a preferred technical solution of the present invention, the antioxidant is one of antioxidant 1010 and antioxidant 168.

[0011] As a preferred technical solution of the present invention, the compatibilizer is one of maleic anhydride grafted polyethylene, ethylene-acrylic acid copolymer and ethylene-methacrylic acid copolymer.

[0012] As a preferred technical solution of the present invention, the lubricant is one of polyethylene wax, silicone and pentaerythritol stearate.

[0013] As a preferred technical solution of the present invention, the dispersant is one of polyvinyl pyrrolidone and sodium polyacrylate.

[0014] A method for preparing a high-strength wear-resistant polyamide material comprises the following steps: S1. Mix 5-8 parts of modified silica sol and 10-15 parts of modified glass fiber by weight to obtain slurry A. S2. Stir 65-80 parts of polyamide matrix material and 10-15 parts of wear-resistant masterbatch at 50-60°C for 1-2 hours, then add slurry A and stir for 30-60 minutes to obtain slurry B; S3. Continue to add 0.5-1 parts of lubricating dispersant and 0.2-0.5 parts of antioxidant to slurry B, maintain the temperature and continue mixing for 2-3 hours, and extrude to obtain the high-strength and wear-resistant polyamide material.

[0015] As a preferred technical solution of the present invention, the extrusion is carried out in a twin-screw extruder, with the barrel temperature set at 260-280° C. and the rotation speed set at 300-500 rpm.

[0016] When preparing the polyamide material, the present invention further adds wear-resistant masterbatch, modified glass fiber and modified silica sol to the polyamide matrix resin to improve the wear resistance and mechanical properties of the polyamide.

[0017] Glass fiber is used as a rigid filler, and a dispersant is added to prevent the glass fiber from agglomerating, ensuring that it is evenly dispersed in the solution, providing a basis for the subsequent uniform deposition of cerium salts. Under alkaline conditions, cerium sulfate is promoted to hydrolyze and adsorb on the surface of the glass fiber. Then, through aging and high-temperature sintering, the product is fully dehydrated and crystallized to form a stable CeO2 coating layer, while removing residual organic matter. This cerium oxide coating can improve thermal stability, and the stability of CeO2 in acidic and alkaline environments is better than that of bare glass fiber, which can reduce the risk of interfacial corrosion of polyamide composites in humid environments. It is then treated with a silane coupling agent to greatly improve the interfacial bonding strength between the fiber and the matrix. The CeO2 coating blocks the penetration of water molecules, and KH550 reduces interfacial microcracks, thereby obtaining a high-quality polyamide material.

[0018] Compared to directly adding glass fibers, the modified glass fibers of the present invention, coated with cerium oxide and treated with a silane coupling agent, are functionalized before composite application, preventing coupling agent failure during polyamide processing and improving process stability. Furthermore, the uncoated glass fibers have only silanol groups on their surface, limiting the number of binding sites for the silane coupling agent. Furthermore, the coupling agent tends to form physical adsorption rather than chemical bonding on the fiber surface, making debonding at the interface between the glass fiber and the polyamide matrix prone to stress concentration, resulting in limited improvement in mechanical properties. Modified glass fibers improve wettability and promote uniform dispersion.

[0019] At the same time, the modified silica sol provides nano-SiO2 particles with a high specific surface area, which act as a reinforcing phase to enhance the rigidity and strength of polyamide, avoiding the brittleness defects of traditional micron fillers. By modifying the nano-silica sol, it can be mixed with modified glass fiber when preparing the polyamide material, thereby better integrating the silica sol and modified glass fiber raw materials into the product system, synergistically enhancing the quality of the polyamide.

[0020] In the present invention, flake graphite is treated with an acid solution for carboxylation, and the BN surface is partially stripped with 30% HNO3 to form a hydroxylated surface, thereby increasing reactivity and improving its dispersibility in polymers. In the acid solution, the carboxyl groups of graphite oxide and the hydroxyl groups of hydroxylated boron nitride undergo esterification to form a chemically bonded interface. At the same time, the acid environment promotes the electrostatic adsorption and physical entanglement of graphite and boron nitride, forming a three-dimensional network structure. Flake graphite provides lubricity, and boron nitride provides high hardness and thermal conductivity, and the two work together to reduce the wear rate. When flake graphite and nano-boron nitride are directly added, they are easily debonded by physical adsorption with the polyamide matrix. Through the three-step modification strategy of graphite carboxylation, boron nitride surface activation, and chemical bonding, the resulting wear-resistant agent is much higher than directly adding untreated graphite and boron nitride in terms of dispersibility, interfacial strength, and multifunctional synergy, thereby further improving wear resistance.

[0021] Beneficial effects of the present invention: The present invention combines self-lubrication with high hardness by adding a chemically bonded wear-resistant agent to a polyamide matrix material, and then adds modified silica sol and modified glass fiber as fillers to synergistically improve the wear resistance of the polyamide. Together with other ingredients, a polyamide material with high strength and good wear resistance is obtained. DETAILED DESCRIPTION

[0022] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation methods, structures, features and effects of the present invention are described in detail below in combination with preferred embodiments.

[0023] In the following examples and comparative examples: The polyamide matrix material was PA66 101 NC010 from DuPont, USA; the pH of the Tris-HCl buffer solution was 8-10; high-density polyethylene was purchased from Shanghai Pengyue New Materials Co., Ltd., item number: HYA-600; zirconium oxide was purchased from Wuhan Jiyesheng Chemical Co., Ltd.; maleic anhydride-grafted polyethylene was purchased from Shanghai MacLean Biochemical Technology Co., Ltd., product number: P875047; polyethylene wax was purchased from Wuhan Kanos Technology Co., Ltd., brand: Kanos; silica sol was purchased from Ningbo Yutian Materials Technology Co., Ltd.; hydroxyethyl cellulose was purchased from Shanghai Kaisai Chemical Co., Ltd., item number: 9004-62-0; zirconium nitrate was purchased from Wuhan Kanos Technology Co., Ltd.; lemon Acid: purchased from Shanghai Yuanye Biotechnology Co., Ltd.; glass fiber: purchased from Wuhan Jixin Yibang Biotechnology Co., Ltd., product number: 20231115; sodium polyacrylate: purchased from Shanghai Yuanye Biotechnology Co., Ltd.; cerium sulfate: purchased from Hubei Yongkuo Technology Co., Ltd.; silane coupling agent KH550: purchased from Shanghai Yuanye Biotechnology Co., Ltd.; flake graphite: purchased from Wuhan Jiyesheng Chemical Co., Ltd.; nano-boron nitride: purchased from Shanghai Myrrel Biochemical Technology Co., Ltd.; polydimethylsiloxane: purchased from Shanghai MacLean Biochemical Technology Co., Ltd., product number: P822627; antioxidant 168: purchased from Shanghai Yien Chemical Technology Co., Ltd.

[0024] When preparing the modified glass fiber, the alkali used in step S2.1 is sodium hydroxide.

[0025] Example 1

[0026] Preparation of wear-resistant masterbatch: In parts by weight, 45 parts of high-density polyethylene, 10 parts of wear-resistant agent, 10 parts of zirconium oxide, 10 parts of maleic anhydride grafted polyethylene and 1 part of polyethylene wax are mixed, stirred at a speed of 1000r / min for 60 minutes in a high-speed mixer, and then sheared, plasticized and granulated at 160°C through a twin-screw extruder to prepare the wear-resistant masterbatch, wherein the wear-resistant agent is flake graphite and nano-boron nitride obtained by treatment.

[0027] Preparation of modified silica sol: In parts by weight, 3 parts of nano-silica sol and 1 part of hydroxyethyl cellulose were added to 5 parts of Tris-HCl buffer solution, and then 2 parts of 3% zirconium nitrate solution and 0.3 parts of citric acid were added, and the mixture was stirred at a speed of 500 r / min for 3 hours to obtain a modified silica sol.

[0028] Preparation of modified glass fiber: S2.1. In parts by weight, 5 parts of glass fiber and 2 parts of sodium polyacrylate were added to 75 parts of deionized water with stirring to obtain a mixture A. The mixture was heated to 80°C, and the pH of the mixture A was adjusted to 8-9 with alkali. 5 parts of cerium sulfate were added, and the mixture was stirred and aged for 1 hour. The pH of the mixture A was further adjusted to 8-10 with the addition of alkali, and the temperature was maintained for aging for 1 hour. The mixture was filtered, washed, and dried to obtain a solid B. S2.2, sintering solid B at 400°C for 3 h to obtain cerium oxide-coated glass fiber; S2.3. Mix the silane coupling agent KH550 with an ethanol-water solution in a volume ratio of 90:10 to obtain a 10% by mass KH550 solution, adjust the pH to 6 with acetic acid, stir evenly, add the cerium oxide-coated glass fiber, continue stirring for 4 hours, filter, and vacuum dry to obtain the modified glass fiber.

[0029] Preparation of wear-resistant agent: S3.1. Mix hydrogen peroxide, potassium permanganate, 30% concentrated sulfuric acid, and flake graphite in a mass ratio of 3:8:150:100, stir at 60°C for 8 h, filter, wash with deionized water, and dry in vacuo at 80°C for 24 h to obtain solid C. S3.2. Soak the nano-boron nitride in a 30% by mass nitric acid solution for 5 minutes, filter, rinse with water, add the nano-boron nitride and hydroxypropanol to ethanol, stir at 500 r / min for 5 hours, filter, and wash with water to obtain solid D, wherein the mass ratio of hydroxypropanol to nano-boron nitride is 1:10; S3.3. Stir solid C and solid D in a mass ratio of 1:5 in an acid solution at a speed of 500 r / min for 5 h to obtain the anti-wear agent.

[0030] Preparation of high-strength and wear-resistant polyamide materials: S1. Mix 5 parts of modified silica sol and 10 parts of modified glass fiber by weight to obtain slurry A; S2. 65 parts of polyamide matrix material and 10 parts of wear-resistant masterbatch were stirred at 800 r / min at 50° C. for 1 h, and then slurry A was added and stirred for 30 min to obtain slurry B; S3. Continue to add 0.5 parts of polydimethylsiloxane and 0.2 parts of antioxidant 168 to slurry B, maintain the temperature and continue mixing for 2 hours, and extrude to obtain the high-strength and wear-resistant polyamide material. The extrusion is carried out in a twin-screw extruder, and the barrel temperature is set to 260° C. and the speed is 300 rpm.

[0031] Example 2

[0032] Preparation of wear-resistant masterbatch: In parts by weight, 50 parts of high-density polyethylene, 15 parts of wear-resistant agent, 13 parts of zirconium oxide, 13 parts of maleic anhydride grafted polyethylene and 2 parts of polyethylene wax are mixed, stirred at a speed of 1000r / min for 70 minutes in a high-speed mixer, and then sheared, plasticized and granulated at 180°C through a twin-screw extruder to prepare the wear-resistant masterbatch, wherein the wear-resistant agent is flake graphite and nano-boron nitride obtained by treatment.

[0033] Preparation of modified silica sol: In parts by weight, 4 parts of nano-silica sol and 1.5 parts of hydroxyethyl cellulose were added to 6 parts of Tris-HCl buffer solution, and then 2.5 parts of 4% zirconium nitrate solution and 0.4 parts of citric acid were added, and the mixture was stirred at a speed of 500 r / min for 3 hours to obtain a modified silica sol.

[0034] Preparation of modified glass fiber: S2.1. In parts by weight, 8 parts of glass fiber and 3 parts of sodium polyacrylate were added to 80 parts of deionized water with stirring to obtain a mixture A, which was heated to 85°C. The pH of the mixture A was adjusted to 8-9 with alkali, 8 parts of cerium sulfate were added, and the mixture was stirred and aged for 1.5 hours. The pH of the mixture A was further adjusted to 8-10 with the addition of alkali, and the temperature was maintained for aging for 2 hours. The mixture was filtered, washed, and dried to obtain a solid B. S2.2, sintering solid B at 500°C for 4 h to obtain cerium oxide-coated glass fiber; S2.3. Mix the silane coupling agent KH550 with an ethanol-water solution in a volume ratio of 90:10 to obtain a 13% by mass KH550 solution, adjust the pH to 6 with acetic acid, stir evenly, add the cerium oxide-coated glass fiber, continue stirring for 6 hours, filter, and vacuum dry to obtain the modified glass fiber.

[0035] Preparation of wear-resistant agent: S3.1. Mix hydrogen peroxide, potassium permanganate, 30% by mass of concentrated sulfuric acid, and flake graphite in a mass ratio of 3:8:150:100, stir at 70°C for 10 h, filter, wash with deionized water, and dry in vacuo at 80°C for 24 h to obtain solid C. S3.2. Soak the nano-boron nitride in a 30% by mass nitric acid solution for 8 minutes, filter, rinse with water, add the nano-boron nitride and hydroxypropanol to ethanol, stir at 500 r / min for 7 hours, filter, and wash with water to obtain solid D, wherein the mass ratio of hydroxypropanol to nano-boron nitride is 1:10; S3.3. Stir solid C and solid D in a mass ratio of 1:6 in an acid solution at a speed of 500 r / min for 6 h to obtain the wear-resistant agent.

[0036] Preparation of high-strength and wear-resistant polyamide materials: S1. Mix 7 parts of modified silica sol and 13 parts of modified glass fiber by weight to obtain slurry A; S2. Stir 70 parts of polyamide matrix material and 13 parts of wear-resistant masterbatch at 55° C. for 1.5 h, then add slurry A and stir for 40 min to obtain slurry B; S3. Continue to add 0.8 parts of polydimethylsiloxane and 0.3 parts of antioxidant 168 to slurry B, maintain the temperature and continue mixing for 2.5 hours, and extrude to obtain the high-strength and wear-resistant polyamide material. The extrusion is carried out in a twin-screw extruder, and the barrel temperature is set to 260° C. and the speed is 400 rpm.

[0037] Example 2

[0038] Preparation of wear-resistant masterbatch: In parts by weight, 60 parts of high-density polyethylene, 20 parts of wear-resistant agent, 15 parts of zirconium oxide, 15 parts of maleic anhydride grafted polyethylene and 3 parts of polyethylene wax are mixed, stirred at a speed of 1000r / min for 90 minutes in a high-speed mixer, and then sheared, plasticized and granulated at 190°C through a twin-screw extruder to prepare the wear-resistant masterbatch, wherein the wear-resistant agent is flake graphite and nano-boron nitride obtained by treatment.

[0039] Preparation of modified silica sol: In parts by weight, 5 parts of nano-silica sol and 2 parts of hydroxyethyl cellulose were added to 8 parts of Tris-HCl buffer solution, and then 3 parts of 5% by weight zirconium nitrate solution and 0.5 parts of citric acid were added, and the mixture was stirred at a speed of 500 r / min for 3 hours to obtain a modified silica sol.

[0040] Preparation of modified glass fiber: S2.1. In parts by weight, 10 parts of glass fiber and 2-4 parts of sodium polyacrylate were added to 100 parts of deionized water, and stirred to obtain a mixture A. The mixture was heated to 90°C, and the pH value of the mixture A was adjusted to 8-9 with alkali. 10 parts of cerium sulfate were added, and the mixture was stirred and aged for 2 hours. The pH value of the mixture A was further adjusted to 8-10 with the addition of alkali, and the temperature was maintained for aging for 3 hours. The mixture was filtered, washed, and dried to obtain a solid B. S2.2, sintering solid B at 600°C for 5 h to obtain cerium oxide-coated glass fiber; S2.3. Mix the silane coupling agent KH550 with an ethanol-water solution in a volume ratio of 90:10 to obtain a 15% by mass KH550 solution, adjust the pH to 6 with acetic acid, stir evenly, add the cerium oxide-coated glass fiber, continue stirring for 7 hours, filter, and vacuum dry to obtain the modified glass fiber.

[0041] Preparation of wear-resistant agent: S3.1. Mix hydrogen peroxide, potassium permanganate, 30% by mass of concentrated sulfuric acid, and flake graphite in a mass ratio of 3:8:150:100, stir at 80°C for 12 h, filter, wash with deionized water, and dry in vacuo at 80°C for 24 h to obtain solid C. S3.2. Soak the nano-boron nitride in a 30% by mass nitric acid solution for 10 minutes, filter, rinse with water, add the nano-boron nitride and hydroxypropanol to ethanol, stir at 500 r / min for 8 hours, filter, and wash with water to obtain solid D, wherein the mass ratio of hydroxypropanol to nano-boron nitride is 1:10; S3.3. Stir solid C and solid D in a mass ratio of 1:8 in an acid solution at a speed of 500 r / min for 7 h to obtain the wear-resistant agent.

[0042] Preparation of high-strength and wear-resistant polyamide materials: S1. Mix 8 parts of modified silica sol and 15 parts of modified glass fiber by weight to obtain slurry A; S2. Stir 80 parts of polyamide matrix material and 15 parts of wear-resistant masterbatch at 60° C. for 2 h, then add slurry A and stir for 60 min to obtain slurry B; S3. 1 part of polydimethylsiloxane and 0.5 part of antioxidant 168 were further added to slurry B, the temperature was maintained and the mixing was continued for 3 hours, and the high-strength and wear-resistant polyamide material was obtained by extrusion. The extrusion was carried out in a twin-screw extruder with the barrel temperature set at 280° C. and the rotation speed at 500 rpm.

[0043] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that the wear-resistant agent in Comparative Example 1 is a direct mixture of flake graphite and nano-boron nitride without any modification treatment, and the other operations are the same.

[0044] Comparative Example 2 The difference between Comparative Example 2 and Example 1 is that zirconium nitrate is not added to the modified silica sol in Comparative Example 2, and the other operations are the same.

[0045] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that the modified glass fiber in Comparative Example 3 is not treated with cerium sulfate during the preparation process, and the other operations are the same.

[0046] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that the modified glass fiber in Comparative Example 4 was not treated with KH550 during the preparation process, and the other operations were the same.

[0047] Comparative Example 5 The difference between Comparative Example 5 and Example 1 is that the glass fiber in Comparative Example 5 is not subjected to any modification treatment, and the other operations are the same.

[0048] Comparative Example 6 The difference between Comparative Example 6 and Example 1 is that no modified silica sol is added in Comparative Example 6, and the other operations are the same.

[0049] Performance testing: Tensile properties: in accordance with GB / T 1040.2-2006; Notched impact strength: in accordance with GB / T1043.1-2008; Wear resistance: According to the standard GB / T3960-2016, the wear amount was tested under the conditions of 200N, 200rpm, and 120min. The sample size was: 30mm*6mm*7mm. The test results are shown in Table 1 below: Table 1 Group Tensile strength / MPa Notched impact strength / MPa Wear resistance / mg / loss per 1000 times Example 1 140 10.6 1.6 Example 2 143 11.1 1.4 Example 3 138 10.3 1.9 Comparative Example 1 125 9.0 2.7 Comparative Example 2 136 9.9 2.0 Comparative Example 3 132 9.2 2.5 Comparative Example 4 128 9.4 2.3 Comparative Example 5 127 8.9 2.9 Comparative Example 6 133 9.4 2.2 According to the above data, the polyamide material prepared by the present invention has excellent strength and wear resistance.

[0050] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A high-strength wear-resistant polyamide material, characterized in that: The invention comprises the following raw materials in parts by weight: 65-80 parts of a polyamide matrix material, 0.5-1 parts of a lubricating dispersant, 10-15 parts of a wear-resistant masterbatch, 5-8 parts of a modified silica sol, 10-15 parts of a modified glass fiber, and 0.2-0.5 parts of an antioxidant, wherein the modified glass fiber is treated with cerium sulfate and a silane coupling agent; The preparation process of the wear-resistant masterbatch is as follows: In parts by weight, 45 to 60 parts of high-density polyethylene, 10 to 20 parts of a wear-resistant agent, 10 to 15 parts of zirconium oxide, 10 to 15 parts of a compatibilizer, and 1 to 3 parts of a lubricant are mixed, stirred at a speed of 1000 r / min for 60 to 90 minutes in a high-speed mixer, and then sheared, plasticized, and granulated at 160 to 190° C. through a twin-screw extruder to prepare the wear-resistant masterbatch, wherein the wear-resistant agent is flake graphite and nano-boron nitride that have been processed; The preparation process of modified silica sol is as follows: In parts by weight, 3 to 5 parts of nano-silica sol and 1 to 2 parts of hydroxyethyl cellulose are added to 5 to 8 parts of Tris-HCl buffer solution, and then 2 to 3 parts of 3 to 5% by weight zirconium nitrate solution and 0.3 to 0.5 parts of citric acid are added, and the mixture is stirred to obtain a modified silica sol.

2. The high-strength wear-resistant polyamide material according to claim 1, characterized in that: The preparation process of the modified glass fiber is as follows: S2.

1. In parts by weight, 5 to 10 parts of glass fiber and 2 to 4 parts of a dispersant were added to 75 to 100 parts of deionized water, and stirred to obtain a mixture A. The mixture was heated to 80 to 90°C, and the pH of the mixture A was adjusted to 8 to 9 with sodium hydroxide. 5 to 10 parts of cerium sulfate were added, and the mixture was stirred and aged for 1 to 2 hours. Sodium hydroxide was further added to adjust the pH of the mixture A to 8 to 10, and the temperature was maintained for aging for 1 to 3 hours. The mixture was filtered, washed, and dried to obtain a solid B. S2.2, sintering solid B at 400-600°C for 3-5 hours to obtain cerium oxide-coated glass fiber; S2.

3. Mix the silane coupling agent KH550 with an ethanol-water solution in a volume ratio of 90:10 to obtain a KH550 solution with a mass fraction of 10-15%, adjust the pH to 6 with acetic acid, stir evenly, add the cerium oxide-coated glass fiber, continue stirring for 4-7 hours, filter, and vacuum dry to obtain the modified glass fiber.

3. The high-strength wear-resistant polyamide material according to claim 1, characterized in that: The preparation process of the anti-wear agent is as follows: S3.

1. Mix hydrogen peroxide, potassium permanganate, 30% concentrated sulfuric acid, and flake graphite in a mass ratio of 3:8:150:100, stir at 60-80°C for 8-12 h, filter, wash with deionized water, and vacuum dry at 80°C for 24 h to obtain solid C. S3.

2. Soak the nano-boron nitride in a 30% by mass nitric acid solution for 5-10 minutes, filter, rinse with water, and then add the nano-boron nitride and hydroxypropanol to ethanol. Stir for 5-8 hours, filter, and wash with water to obtain solid D, wherein the mass ratio of hydroxypropanol to nano-boron nitride is 1:

10. S3.

3. Stir solid C and solid D in an acid solution at a mass ratio of 1:(5-8) for 5-7 hours to obtain the wear-resistant agent.

4. The high-strength wear-resistant polyamide material according to claim 1, characterized in that: The lubricating dispersant is one or more of pentaerythritol stearate, ethylene acrylic acid copolymer and polydimethylsiloxane.

5. The high-strength wear-resistant polyamide material according to claim 1, characterized in that: The antioxidant is one of antioxidant 1010 and antioxidant 168.

6. The high-strength wear-resistant polyamide material according to claim 2, characterized in that: The compatibilizer is one of maleic anhydride grafted polyethylene, ethylene-acrylic acid copolymer and ethylene-methacrylic acid copolymer.

7. The high-strength wear-resistant polyamide material according to claim 2, characterized in that: The lubricant is one of polyethylene wax, silicone and pentaerythritol stearate.

8. The high-strength wear-resistant polyamide material according to claim 2, characterized in that: The dispersant is one of polyvinyl pyrrolidone and sodium polyacrylate.

9. A method for preparing the high-strength wear-resistant polyamide material according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1. Mix 5-8 parts of modified silica sol and 10-15 parts of modified glass fiber by weight to obtain slurry A. S2. Stir 65-80 parts of polyamide matrix material and 10-15 parts of wear-resistant masterbatch at 50-60°C for 1-2 hours, then add slurry A and stir for 30-60 minutes to obtain slurry B; S3. Continue to add 0.5-1 parts of lubricating dispersant and 0.2-0.5 parts of antioxidant to slurry B, maintain the temperature and continue mixing for 2-3 hours, and extrude to obtain the high-strength and wear-resistant polyamide material.

10. The method for preparing a high-strength wear-resistant polyamide material according to claim 9, characterized in that: The extrusion is carried out in a twin-screw extruder, with the barrel temperature set at 260-280° C. and the rotation speed set at 300-500 rpm.