Preparation method of modified high-density polyethylene material

Abstract

The invention provides a preparation method of a modified high-density polyethylene material, and relates to the field of high-density polyethylene materials. The modified high-density polyethylene material comprises 70%-85% of high-density polyethylene, 5%-15% of a flexibilizer, 3%-10% of an environmental stress cracking resistant modifier, 1%-5% of a heat stabilizer, 0.5%-2% of an antioxidant, 0.5%-3% of a nano inorganic filler and 0.5%-3% of other functional additives. By optimizing the combination of the flexibilizer, the environmental stress cracking resistance modifier, the heat stabilizer and the antioxidant, the problem that the environmental stress cracking resistance of the material is reduced due to the introduction of the modifier or filler in the prior art is effectively solved; the impact resistance and the flexibility of the material are improved.

Description

Technical Field

[0001] The invention relates to the technical field of high-density polyethylene materials, in particular to a method for preparing a modified high-density polyethylene material. Background Art

[0002] Modified high-density polyethylene materials are based on the original high-density polyethylene, and various modifiers or fillers such as glass fiber, mineral fillers, flame retardants, etc. are added to improve its mechanical properties, heat resistance, aging resistance and other properties. This modification can be achieved through blending, grafting, cross-linking and other methods, so that the HDPE material not only retains its original excellent properties (such as high rigidity, good chemical resistance and excellent electrical insulation), but also can meet more stringent application requirements. The modified HDPE material usually exhibits higher tensile strength, impact resistance and better processing performance, so it has been widely used in pipes, films, wires and cables, automotive accessories and other fields.

[0003] However, modified high-density polyethylene materials also have some defects. The introduction of modifiers or fillers may cause the material's resistance to environmental stress cracking to decrease, making the material prone to cracking or breaking under long-term load. Some modifiers may affect the material's thermoplastic processing properties, making processing more difficult, especially under high temperature conditions, which can easily cause material degradation or processing defects. Summary of the invention

[0004] 1. Technical issues to be resolved

[0005] In view of the deficiencies in the prior art, the present invention provides a method for preparing a modified high-density polyethylene material, which solves the problem that the introduction of modifiers or fillers leads to a decrease in the material's resistance to environmental stress cracking, making the material prone to cracking or breaking under long-term load; the modifier affects the material's thermoplastic processing properties and is likely to cause material degradation or processing defects.

[0006] (II) Technical solution

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions: A modified high-density polyethylene material, comprising:

[0008] High-density polyethylene: 70%-85%, toughening agent: 5%-15%, environmental stress cracking resistance modifier: 3%-10%, heat stabilizer: 1%-5%, antioxidant: 0.5%-2%, nano-inorganic filler: 0.5%-3%, other functional additives: 0.5%-3%.

[0009] Preferably, the toughening agent is ethylene-vinyl acetate copolymer or ethylene-propylene copolymer, which is used to improve the impact resistance and flexibility of the material, and the environmental stress cracking resistance modifier is an organosilicon compound or a high-efficiency anti-stress cracking agent, which can significantly improve the environmental stress cracking resistance of the material and reduce the risk of cracking during long-term use.

[0010] Preferably, the heat stabilizer is a benzotriazole or bisphenol A antioxidant, which is used to enhance the thermal stability of the material under high temperature conditions and prevent the material from degrading during high temperature processing. The antioxidant is a phenolic antioxidant, which can effectively inhibit the oxidative degradation of the material during processing and use, and improve the aging resistance of the material. The nano inorganic filler is nano silicon dioxide or nano calcium carbonate, which has been surface modified to improve its dispersibility and interface compatibility in the polymer matrix, thereby improving the mechanical properties and thermal stability of the material. The other functional additives include UV inhibitors, lubricants or pigments, which are used to enhance the weather resistance, processing performance and aesthetics of the material.

[0011] A method for preparing a modified high-density polyethylene material comprises the following steps:

[0012] a. Raw material preparation: prepare the raw materials according to the above weight percentage;

[0013] b. Premixing of toughening agent: premix the toughening agent with part of high-density polyethylene to form a uniform mixture to improve the impact resistance and flexibility of the material;

[0014] c. Addition of environmental stress cracking resistance modifier: Add the environmental stress cracking resistance modifier to the premix and perform preliminary mixing at a temperature of 120°C to 160°C to fully disperse it in the matrix and enhance the environmental stress cracking resistance of the material;

[0015] d. Surface treatment of nano-inorganic fillers: Surface modification of nano-inorganic fillers is performed by using organic silane or titanate coupling agents to modify their surfaces in order to improve their dispersibility and interfacial compatibility in the polymer matrix;

[0016] e. Addition of nano-inorganic fillers: Mix the surface-treated nano-inorganic fillers with high-density polyethylene and other additives, and melt blend them at a temperature of 180°C to 220°C to evenly distribute the fillers in the matrix, thereby improving the mechanical properties and thermal stability of the material;

[0017] f. Addition of heat stabilizer and antioxidant: Add heat stabilizer and antioxidant to the mixture in proportion, and continue to blend at a temperature of 150°C to 200°C to prevent the material from degrading during high-temperature processing and improve the heat resistance and aging resistance of the material;

[0018] g. Addition of other functional additives: Adding functional additives such as UV inhibitors, lubricants or pigments to the mixture to further enhance the weather resistance, processing performance and aesthetics of the material;

[0019] h. Twin-screw extrusion: The mixture is melt-extruded through a twin-screw extruder at a temperature range of 180°C to 220°C to fully mix and evenly disperse the materials to form a molten modified high-density polyethylene;

[0020] i. Melt blending time control: Control the melt blending time to 2 to 10 minutes to ensure that the components are fully reacted and evenly distributed to avoid material degradation or processing defects;

[0021] j. Cooling and molding: The molten modified high-density polyethylene is molded through a mold and rapidly cooled to form the final modified material product;

[0022] k. Testing and adjustment: Test the molded modified materials, including mechanical properties, environmental stress cracking resistance, thermal stability and oxidation resistance, and adjust production parameters according to the test results to optimize product performance;

[0023] l. Recycling and reuse: For the scraps or waste generated in the production process, they can be recycled into the production process through appropriate crushing, cleaning and reprocessing processes to improve the utilization rate of materials and environmental protection performance.

[0024] Preferably, the environmental stress cracking resistance modifier is an organosilicon compound or a high-efficiency stress cracking resistance agent, which can significantly improve the environmental stress cracking resistance of the material and reduce the risk of cracking during long-term use. The thermal stabilizer is a benzotriazole or bisphenol A antioxidant, which is used to enhance the thermal stability of the material under high temperature conditions and prevent the material from degrading during high temperature processing.

[0025] Preferably, the antioxidant is a phenolic antioxidant, which can effectively inhibit the oxidative degradation of the material during processing and use, and improve the aging resistance of the material. The nano inorganic filler is nano silicon dioxide or nano calcium carbonate, which has been surface modified to improve its dispersibility and interface compatibility in the polymer matrix, thereby improving the mechanical properties and thermal stability of the material.

[0026] Preferably, the particle size of the nano inorganic filler is between 10 and 100 nanometers, and the surface is treated with a coupling agent to enhance the interfacial bonding between the filler and the polyethylene matrix, thereby further improving the tensile strength and durability of the material.

[0027] Preferably, the material can still maintain good processing performance and stable mechanical properties under conditions of ≥100°C, and is suitable for application in outdoor high-temperature environments. The addition amount of the nano inorganic filler is 0.5% to 3% of the total weight, and it is blended through a high-shear mixing device to ensure the uniform distribution of the filler in the polymer matrix and avoid fluctuations in material properties. The material further improves the flexibility and impact resistance of the material by adding a thermoplastic elastomer as an auxiliary toughening agent, which works synergistically with the main toughening agent.

[0028] (III) Beneficial effects

[0029] The present invention provides a method for preparing a modified high-density polyethylene material, which has the following beneficial effects:

[0030] By optimizing the combination of toughening agents, environmental stress cracking resistance modifiers, heat stabilizers and antioxidants, the present invention effectively solves the problem in the prior art that the environmental stress cracking resistance of materials decreases due to the introduction of modifiers or fillers. Ethylene-vinyl acetate copolymers or ethylene-propylene copolymers are used as toughening agents to improve the impact resistance and flexibility of the materials. At the same time, by adding organic silicon compounds or high-efficiency stress cracking resistance agents, the environmental stress cracking resistance of the materials under long-term loads is greatly enhanced, and the risks of cracking and fracture are reduced. The reasonable ratio of heat stabilizers and antioxidants further improves the thermal stability and aging resistance of the materials under high temperature conditions, and effectively prevents degradation during processing.

[0031] Through surface modification treatment, the uniform dispersion and interface compatibility of the filler in the polymer matrix are ensured, thereby significantly improving the mechanical properties and thermal stability of the material. In addition, the present invention ensures the uniform distribution of each component in the high-density polyethylene matrix through advanced processes such as twin-screw extrusion and melt blending, avoiding fluctuations in material properties. The final modified high-density polyethylene material not only has excellent environmental stress cracking resistance and thermal stability, but also has good processing performance and flexibility, and is particularly suitable for application in outdoor high-temperature environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a schematic diagram of the internal structure of the present invention. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] like Figure 1As shown, the embodiment of the present invention provides a modified high-density polyethylene material, including high-density polyethylene: 70%-85%, toughening agent: 5%-15%, environmental stress cracking resistance modifier: 3%-10%, heat stabilizer: 1%-5%, antioxidant: 0.5%-2%, nano inorganic filler: 0.5%-3%, other functional additives: 0.5%-3%, the toughening agent is ethylene-vinyl acetate copolymer or ethylene-propylene copolymer, which is used to improve the impact resistance and flexibility of the material, and the environmental stress cracking resistance modifier is an organic silicon compound or a high-efficiency stress cracking resistance agent, which can significantly improve the environmental stress cracking resistance of the material and reduce long-term The risk of cracking during use. The heat stabilizer is a benzotriazole or bisphenol A antioxidant, which is used to enhance the thermal stability of the material under high temperature conditions and prevent the material from degrading during high temperature processing. The antioxidant is a phenolic antioxidant, which can effectively inhibit the oxidative degradation of the material during processing and use, and improve the aging resistance of the material. The nano-inorganic filler is nano-silicon dioxide or nano-calcium carbonate, which has been surface-modified to improve its dispersibility and interfacial compatibility in the polymer matrix, thereby improving the mechanical properties and thermal stability of the material. Other functional additives include UV inhibitors, lubricants or pigments, which are used to enhance the weather resistance, processing performance and aesthetics of the material.

[0035] A method for preparing a modified high-density polyethylene material, characterized in that it comprises the following steps:

[0036] a. Raw material preparation: prepare the raw materials according to the above weight percentages.

[0037] b. Premixing of toughening agent: Premix the toughening agent with part of high-density polyethylene to form a uniform mixture to improve the impact resistance and flexibility of the material.

[0038] c. Addition of environmental stress cracking resistance modifier: Add the environmental stress cracking resistance modifier to the premix and perform preliminary mixing at a temperature of 120°C to 160°C to fully disperse it in the matrix to enhance the environmental stress cracking resistance of the material. The environmental stress cracking resistance modifier is an organosilicon compound or a high-efficiency anti-stress cracking agent, which can significantly improve the environmental stress cracking resistance of the material and reduce the risk of cracking in long-term use. The thermal stabilizer is a benzotriazole or bisphenol A antioxidant, which is used to enhance the thermal stability of the material under high temperature conditions and prevent the material from degrading during high temperature processing.

[0039] d. Surface treatment of nano-inorganic fillers: Surface modification of nano-inorganic fillers is performed by using organic silane or titanate coupling agents to improve their dispersibility and interfacial compatibility in the polymer matrix. The particle size of the nano-inorganic fillers is between 10 and 100 nanometers, and the surface is treated with coupling agents to enhance the interfacial bonding between the fillers and the polyethylene matrix, thereby further improving the tensile strength and durability of the material.

[0040] e. Addition of nano-inorganic fillers: Mix the surface-treated nano-inorganic fillers with high-density polyethylene and other additives, and melt-blend them at a temperature of 180°C to 220°C to make the fillers evenly distributed in the matrix, thereby improving the mechanical properties and thermal stability of the material.

[0041] f. Addition of heat stabilizer and antioxidant: Add heat stabilizer and antioxidant to the mixture in proportion, and continue to blend at a temperature of 150°C to 200°C to prevent the material from degrading during high-temperature processing and improve the heat resistance and aging resistance of the material. The antioxidant is a phenolic antioxidant, which can effectively inhibit the oxidative degradation of the material during processing and use, and improve the aging resistance of the material. The nano-inorganic filler is nano-silicon dioxide or nano-calcium carbonate, which has been surface-modified to improve its dispersibility and interface compatibility in the polymer matrix, thereby improving the mechanical properties and thermal stability of the material. The material can still maintain good processing performance and stable mechanical properties under conditions of ≥100°C, and is suitable for application in outdoor high-temperature environments. The addition amount of nano-inorganic filler is 0.5% to 3% of the total weight, and it is blended through a high-shear mixing device to ensure uniform distribution of the filler in the polymer matrix and avoid fluctuations in material properties. The material further improves the flexibility and impact resistance of the material by adding a thermoplastic elastomer as an auxiliary toughening agent to synergize with the main toughening agent.

[0042] g. Addition of other functional additives: Add functional additives such as UV inhibitors, lubricants or pigments to the mixture to further enhance the material's weather resistance, processing performance and aesthetics.

[0043] h. Twin-screw extrusion: The above mixture is melt-extruded through a twin-screw extruder at a temperature range of 180°C to 220°C to fully mix and evenly disperse the materials to form a modified high-density polyethylene in a molten state.

[0044] i. Melt blending time control: Control the melt blending time to 2 to 10 minutes to ensure that the components are fully reacted and evenly distributed to avoid material degradation or processing defects.

[0045] j. Cooling molding: The molten modified high-density polyethylene is molded through a mold and quickly cooled to form the final modified material product.

[0046] k. Testing and adjustment: Test the molded modified materials, including mechanical properties, environmental stress cracking resistance, thermal stability and oxidation resistance, and adjust production parameters based on the test results to optimize product performance.

[0047] l. Recycling and reuse: For the scraps or waste generated in the production process, they can be recycled into the production process through appropriate crushing, cleaning and reprocessing processes to improve the utilization rate of materials and environmental protection performance.

[0048] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A modified high-density polyethylene material, characterized in that: include: High-density polyethylene: 70%-85%, toughening agent: 5%-15%, environmental stress cracking resistance modifier: 3%-10%, heat stabilizer: 1%-5%, antioxidant: 0.5%-2%, nano-inorganic filler: 0.5%-3%, other functional additives: 0.5%-3%.

2. A modified high-density polyethylene material according to claim 1, characterized in that: The toughening agent is ethylene-vinyl acetate copolymer or ethylene-propylene copolymer, which is used to improve the impact resistance and flexibility of the material. The environmental stress cracking resistance modifier is an organosilicon compound or a high-efficiency anti-stress cracking agent, which can significantly improve the environmental stress cracking resistance of the material and reduce the risk of cracking during long-term use.

3. A modified high-density polyethylene material according to claim 1, characterized in that: The heat stabilizer is a benzotriazole or bisphenol A antioxidant, which is used to enhance the thermal stability of the material under high temperature conditions and prevent the material from degrading during high temperature processing. The antioxidant is a phenolic antioxidant, which can effectively inhibit the oxidative degradation of the material during processing and use, and improve the aging resistance of the material. The nano inorganic filler is nano silicon dioxide or nano calcium carbonate, which is surface modified to improve its dispersibility and interface compatibility in the polymer matrix, thereby improving the mechanical properties and thermal stability of the material. The other functional additives include UV inhibitors, lubricants or pigments, which are used to enhance the weather resistance, processing performance and aesthetics of the material.

4. A method for preparing a modified high-density polyethylene material, characterized in that: The following steps are involved: a. Raw material preparation: prepare the raw materials according to the above weight percentage; b. Premixing of toughening agent: premix the toughening agent with part of high-density polyethylene to form a uniform mixture to improve the impact resistance and flexibility of the material; c. Addition of environmental stress cracking resistance modifier: Add the environmental stress cracking resistance modifier to the premix and perform preliminary mixing at a temperature of 120°C to 160°C to fully disperse it in the matrix and enhance the environmental stress cracking resistance of the material; d. Surface treatment of nano-inorganic fillers: Surface modification of nano-inorganic fillers is performed by using organic silane or titanate coupling agents to modify their surfaces in order to improve their dispersibility and interfacial compatibility in the polymer matrix; e. Addition of nano-inorganic fillers: Mix the surface-treated nano-inorganic fillers with high-density polyethylene and other additives, and melt blend them at a temperature of 180°C to 220°C to evenly distribute the fillers in the matrix, thereby improving the mechanical properties and thermal stability of the material; f. Addition of heat stabilizer and antioxidant: Add heat stabilizer and antioxidant to the mixture in proportion, and continue to blend at a temperature of 150°C to 200°C to prevent the material from degrading during high-temperature processing and improve the heat resistance and aging resistance of the material; g. Addition of other functional additives: Adding functional additives such as UV inhibitors, lubricants or pigments to the mixture to further enhance the weather resistance, processing performance and aesthetics of the material; h. Twin-screw extrusion: The mixture is melt-extruded through a twin-screw extruder at a temperature range of 180°C to 220°C to fully mix and evenly disperse the materials to form a molten modified high-density polyethylene; i. Melt blending time control: Control the melt blending time to 2 to 10 minutes to ensure that the components are fully reacted and evenly distributed to avoid material degradation or processing defects; j. Cooling and molding: The molten modified high-density polyethylene is molded through a mold and rapidly cooled to form the final modified material product; k. Testing and adjustment: Test the molded modified materials, including mechanical properties, environmental stress cracking resistance, thermal stability and oxidation resistance, and adjust production parameters according to the test results to optimize product performance; l. Recycling and reuse: For the scraps or waste generated in the production process, they can be recycled into the production process through appropriate crushing, cleaning and reprocessing processes to improve the utilization rate of materials and environmental protection performance.

5. The method for preparing a modified high-density polyethylene material according to claim 4, characterized in that: The environmental stress cracking resistance modifier is an organosilicon compound or a high-efficiency stress cracking resistance agent, which can significantly improve the environmental stress cracking resistance of the material and reduce the risk of cracking during long-term use. The thermal stabilizer is a benzotriazole or bisphenol A antioxidant, which is used to enhance the thermal stability of the material under high temperature conditions and prevent the material from degrading during high temperature processing.

6. The method for preparing a modified high-density polyethylene material according to claim 4, characterized in that: The antioxidant is a phenolic antioxidant, which can effectively inhibit the oxidative degradation of the material during processing and use, and improve the aging resistance of the material. The nano inorganic filler is nano silicon dioxide or nano calcium carbonate, which has been surface modified to improve its dispersibility and interface compatibility in the polymer matrix, thereby improving the mechanical properties and thermal stability of the material.

7. The method for preparing a modified high-density polyethylene material according to claim 4, characterized in that: The particle size of the nano inorganic filler is between 10 and 100 nanometers, and the surface is treated with a coupling agent to enhance the interfacial bonding force between the filler and the polyethylene matrix, thereby further improving the tensile strength and durability of the material.

8. The method for preparing a modified high-density polyethylene material according to claim 4, characterized in that: The material can still maintain good processing performance and stable mechanical properties under conditions of ≥100°C, and is suitable for application in outdoor high-temperature environments. The addition amount of the nano inorganic filler is 0.5% to 3% of the total weight, and is blended through a high-shear mixing device to ensure uniform distribution of the filler in the polymer matrix and avoid fluctuations in material properties. The material further improves the flexibility and impact resistance of the material by adding a thermoplastic elastomer as an auxiliary toughening agent, which works synergistically with the main toughening agent.

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