Anti-aging cable protection tube and preparation method thereof

Abstract

The invention relates to the technical field of materials, and discloses an anti-aging cable protection tube and a preparation method thereof.The cable protection tube is prepared by taking polypropylene as a base material and taking an elastomer, a compatilizer, a synergistic antioxidant and the like as auxiliary materials through the processes of mixing, extruding and forming; wherein the synergistic antioxidant is a macromolecular substance with benzimidazole-hindered phenol blocks alternately linked, and can interact with a maleic anhydride group in a molecular chain of the compatilizer in the subsequent high-temperature melt extrusion process, so that the synergistic antioxidant can play a role of a cross-linking agent, the molecular chain of polypropylene is converted into a three-dimensional network structure, and the mechanical property of the polypropylene is improved. The synergistic antioxidant is added into the cable protection pipe, so that the structure of the prepared cable protection pipe is more compact, the mechanical strength of the cable protection pipe is improved, a molecular chain of the synergistic antioxidant contains a large number of hindered phenol structures and benzimidazole structures, the hindered phenol structures and the benzimidazole structures can cooperate with each other, and the effect that the aging resistance of the cable protection pipe can be greatly improved by adding a small amount of the synergistic antioxidant is achieved.

Description

Technical Field

[0001] This invention relates to the field of materials technology, specifically to an anti-aging cable protection pipe and its preparation method. Background Technology

[0002] Cable protection pipes, as infrastructure materials in fields such as power, communications, and transportation, directly affect the safety and service life of cable systems. Among many materials, polypropylene (PP) has become one of the important raw materials for cable protection pipes due to its excellent physical properties and processing characteristics. However, the molecular structure of PP makes it susceptible to aging due to factors such as heat and oxygen during long-term use. Therefore, antioxidant modification has become the key to enhancing its application value.

[0003] Existing technologies typically modify polypropylene by adding small-molecule antioxidants such as hindered phenols to enhance its anti-aging properties. However, due to the low molecular weight of these antioxidants, they are prone to migration and volatilization at high temperatures, which not only reduces their antioxidant efficiency but also causes environmental pollution. Therefore, this presents significant problems in practical applications. Based on this, the present invention provides a cable protection pipe with excellent anti-aging properties, which can solve the problems existing in the prior art. Summary of the Invention

[0004] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an anti-aging cable protection pipe and its preparation method.

[0005] (II) Technical Solution An anti-aging cable protection tube, made from the following raw materials measured in parts by weight: Polypropylene 75-95 parts, elastomer 10-20 parts, compatibilizer 5-15 parts, synergistic antioxidant 0.3-0.6 parts, inorganic additives 4-8 parts, lubricant 2-3 parts, ultraviolet absorber 0.5-1.5 parts, silane coupling agent 1-2 parts; The synergistic antioxidant is a macromolecular substance with alternating benzimidazole-hindered phenol block linkages.

[0006] As a further embodiment of the present invention, the elastomer is at least one of TPU elastomer, SBS elastomer, or SEBS elastomer; the compatibilizer is maleic anhydride-grafted polyethylene or maleic anhydride-grafted polypropylene; the inorganic additive is talc, calcium carbonate, or fumed silica; the lubricant is calcium stearate, zinc stearate, or polyethylene wax; the ultraviolet absorber is any one of ultraviolet absorber UV-531, ultraviolet absorber UV-P, or ultraviolet absorber UV-9; and the silane coupling agent is 3-aminopropyltrimethoxysilane or 3-aminopropyltriethoxysilane.

[0007] As a further aspect of the present invention, the preparation method of the synergistic antioxidant is as follows: Add antioxidant MB derivative, hindered phenolic antioxidant derivative, and N,N-dimethylformamide to a nitrogen-filled reactor. After the addition is complete, start stirring. Once a homogeneous mixture is formed, continue adding catalyst to the reactor, then start heating. Control the heating rate at 3-5℃ / min to raise the temperature to 60-70℃. Hold the temperature for 2-4 hours, then further raise the temperature to 90-100℃. Continue stirring and holding the temperature for 16-24 hours. Stop heating, separate the solid material, and after washing and vacuum drying, the synergistic antioxidant can be obtained.

[0008] As a further aspect of the present invention, the preparation method of the antioxidant MB derivative is as follows: Antioxidant MB, 2-bromosuccinic acid and toluene are added to a reaction vessel. After the addition is complete, the mixture is stirred until homogeneous. Then, an acid-binding agent is added and stirred until homogeneous. The temperature is raised to 70-80℃ and kept at this temperature for 3-6 hours. The solvent is evaporated and removed, the material is cooled and discharged, and the product is collected to obtain the antioxidant MB derivative.

[0009] As a further aspect of the present invention, the molar ratio of the antioxidant MB to 2-bromosuccinic acid is 1:1.

[0010] As a further aspect of the present invention, the acid-binding agent is potassium carbonate or sodium carbonate.

[0011] As a further aspect of the present invention, the method for preparing the hindered phenolic antioxidant derivative is as follows: Add 3,5-bis(tert-butyl)-4-hydroxyphenylpropionyl chloride to acetone and mix well. Then, under ice bath conditions, add 1,3-diepoxyglycerol ether glycerol and triethylamine to the mixture. After the addition is complete, remove the mixture from the ice bath and stir at room temperature for 2-3 hours. Evaporate to remove the solvent, cool down and discharge the product to obtain the hindered phenol antioxidant derivative.

[0012] As a further aspect of the present invention, the molar ratio of 3,5-bis(tert-butyl)-4-hydroxyphenylpropionyl chloride and 1,3-diepoxyglycerol ether glycerol is 1:1.

[0013] As a further aspect of the present invention, the catalyst is any one of tetrabutylammonium bromide, tetramethylammonium bromide, tetrabutylammonium bisulfate, tetrabutylammonium chloride, or tetramethylammonium chloride.

[0014] In the above technical solution, using antioxidant MB derivatives and hindered phenol antioxidant derivatives as reactants, under the action of a phase transfer catalyst, the active carboxyl substituents in their structures can undergo continuous and uninterrupted ring-opening esterification reactions with the active epoxy substituents, thereby obtaining a macromolecular substance with alternating benzimidazole-hindered phenol block linkages, i.e., a synergistic antioxidant.

[0015] Among them, the antioxidant MB derivative is prepared by using antioxidant MB and 2-bromosuccinic acid as raw materials, and by a substitution reaction between the active thiol functional groups and halogen substituents in their structures under the action of an acid-binding agent. The hindered phenolic antioxidant derivative is prepared by using 3,5-bis(tert-butyl)-4-hydroxyphenylpropionyl chloride and 1,3-diepoxyglycerol ether glycerol as raw materials, and by a condensation reaction between the acyl chloride substituents and hydroxyl substituents in their structures.

[0016] A method for preparing an anti-aging cable protection tube includes the following steps: Step 1: Weigh each raw material according to the specified weight proportions and prepare the materials. The second step involves adding all raw materials to a high-speed mixer and mechanically mixing them at a temperature of 100-120℃ and a speed of 500-1000 r / min. Then, the mixture is transferred to a twin-screw extruder, and the temperatures of each zone are controlled as follows: Zone 1 200±5℃, Zone 2 220±5℃, Zone 3 230±5℃, Zone 4 250±5℃, Zone 5 240±5℃, Zone 6 240±5℃, and the die temperature is 240±5℃. The mixture is then melt-extruded and granulated to obtain masterbatch. The masterbatch is then added to the hopper of a pipe extruder and extruded to form the cable protection pipe.

[0017] (iii) Beneficial technical effects This invention prepares a macromolecular substance with alternating benzimidazole-hindered phenol block linkages as a synergistic antioxidant. During the ring-opening polymerization reaction, a large number of active hydroxyl functional groups are generated. These hydroxyl functional groups can interact with the maleic anhydride groups in the compatibilizer molecular chain during the subsequent high-temperature melt extrusion process. Therefore, the synergistic antioxidant can act as a crosslinking agent, transforming the polypropylene molecular chain into a three-dimensional network structure, making the structure of the obtained cable protection pipe more compact and beneficial to improving the mechanical strength of the cable protection pipe. The synergistic antioxidant molecular chain contains a large number of hindered phenol and benzimidazole structures, which can synergistically improve the anti-aging performance of the cable protection pipe with a small amount of addition. Moreover, since the synergistic antioxidant exists in the form of a crosslinking agent, it cannot easily migrate and precipitate, thus ensuring the long-term anti-aging performance of the cable protection pipe. Detailed Implementation

[0018] To facilitate understanding of the present invention, a more complete description will be provided below. Preferred embodiments of the invention are given below. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0019] Example 1: An anti-aging cable protection tube, made from the following raw materials measured in parts by weight: 75 parts polypropylene, 10 parts TPU elastomer, 5 parts maleic anhydride grafted polyethylene, 0.3 parts synergistic antioxidant, 4 parts calcium carbonate, 2 parts calcium stearate, 0.5 parts UV absorber UV-531, and 1 part 3-aminopropyltriethoxysilane agent. The method for preparing the cable protection pipe includes the following steps: Step 1: Weigh each raw material according to the specified weight proportions and prepare the materials. The second step involves adding all the raw materials to a high-speed mixer and mechanically mixing them at 120°C and a speed of 500 r / min. Then, the mixture is transferred to a twin-screw extruder, and the temperatures of each zone are controlled sequentially as follows: Zone 1 200°C, Zone 2 220°C, Zone 3 230°C, Zone 4 250°C, Zone 5 240°C, Zone 6 240°C, and the die temperature is 240°C. The mixture is then melt-extruded and granulated to obtain masterbatch. The masterbatch is then added to the hopper of a pipe extruder and extruded to form the cable protection pipe.

[0020] The preparation method of the synergistic antioxidant is as follows: Step S1: Add 0.4g of antioxidant MB, 0.5g of 2-bromosuccinic acid and toluene to the reaction vessel. After the addition is complete, stir and mix evenly. Then add 0.1g of potassium carbonate, stir evenly, raise the temperature to 75℃, keep it warm and stir for 4h, evaporate and remove the solvent, cool down and discharge the material, collect the product, and the antioxidant MB derivative can be obtained. Step S2: Add 0.2g of 3,5-bis(tert-butyl)-4-hydroxyphenylpropionyl chloride to acetone and mix well. Then, under ice bath conditions, add 0.14g of 1,3-diepoxyglycerol ether glycerol and 0.05g of triethylamine to the mixture. After the addition is complete, remove from the ice bath, stir at room temperature for 3 hours, evaporate to remove the solvent, cool down and discharge the product to obtain the hindered phenol antioxidant derivative. Step S3: Add 0.8g of antioxidant MB derivative, 0.6g of hindered phenolic antioxidant derivative and N,N-dimethylformamide to a nitrogen-filled reactor. After the addition is complete, start stirring. After a uniform mixture is formed, add 0.01g of tetrabutylammonium bromide to the reactor. Then start heating and control the heating rate at 5℃ / min to raise the temperature to 70℃. After holding at this temperature for 3 hours, further raise the temperature to 95℃ and continue stirring for 18 hours. Then stop heating, separate the solid material, and after washing and vacuum drying, the synergistic antioxidant can be obtained.

[0021] Example 2: An anti-aging cable protection tube, made from the following raw materials measured in parts by weight: 80 parts polypropylene, 15 parts SBS elastomer, 10 parts maleic anhydride-grafted polyethylene, 0.5 parts synergistic antioxidant, 6 parts talc, 2.5 parts zinc stearate, 1 part UV absorber UV-P, and 1.5 parts 3-aminopropyltriethoxysilane. The method for preparing the cable protection pipe includes the following steps: Step 1: Weigh each raw material according to the specified weight proportions and prepare the materials. The second step involves adding all the raw materials to a high-speed mixer and mechanically mixing them at 110°C and a speed of 800 r / min. Then, the mixture is transferred to a twin-screw extruder, and the temperatures of each zone are controlled as follows: Zone 1 200°C, Zone 2 220°C, Zone 3 230°C, Zone 4 250°C, Zone 5 240°C, Zone 6 240°C, and the die temperature is 240°C. The mixture is then melt-extruded and granulated to obtain masterbatch. The masterbatch is then added to the hopper of a pipe extruder and extruded to form the cable protection pipe.

[0022] The preparation method of the synergistic antioxidant is the same as that in Example 1.

[0023] Example 3: An anti-aging cable protection tube, made from the following raw materials measured in parts by weight: 95 parts polypropylene, 20 parts SBS elastomer, 15 parts maleic anhydride grafted polyethylene, 0.6 parts synergistic antioxidant, 8 parts fumed silica, 3 parts polyethylene wax, 1.5 parts UV-9 ultraviolet absorber, and 2 parts 3-aminopropyltriethoxysilane. The method for preparing the cable protection pipe includes the following steps: Step 1: Weigh each raw material according to the specified weight proportions and prepare the materials. The second step involves adding all the raw materials to a high-speed mixer and mechanically mixing them at 100°C and 1000 rpm. Then, the mixture is transferred to a twin-screw extruder, and the temperatures of each zone are controlled as follows: Zone 1 200°C, Zone 2 220°C, Zone 3 230°C, Zone 4 250°C, Zone 5 240°C, Zone 6 240°C, and the die temperature is 240°C. The mixture is then melt-extruded and granulated to obtain masterbatch. The masterbatch is then added to the hopper of a pipe extruder and extruded to form the cable protection pipe.

[0024] The preparation method of the synergistic antioxidant is the same as that in Example 1.

[0025] Comparative Example 1 An anti-aging cable protection tube, made from the following raw materials measured in parts by weight: 80 parts polypropylene, 15 parts SBS elastomer, 10 parts maleic anhydride grafted polyethylene, 0.5 parts antioxidant MB, 6 parts talc, 2.5 parts zinc stearate, 1 part ultraviolet absorber UV-P, and 1.5 parts 3-aminopropyltriethoxysilane. The method for preparing the cable protection pipe includes the following steps: Step 1: Weigh each raw material according to the specified weight proportions and prepare the materials. The second step involves adding all the raw materials to a high-speed mixer and mechanically mixing them at 110°C and a speed of 800 r / min. Then, the mixture is transferred to a twin-screw extruder, and the temperatures of each zone are controlled as follows: Zone 1 200°C, Zone 2 220°C, Zone 3 230°C, Zone 4 250°C, Zone 5 240°C, Zone 6 240°C, and the die temperature is 240°C. The mixture is then melt-extruded and granulated to obtain masterbatch. The masterbatch is then added to the hopper of a pipe extruder and extruded to form the cable protection pipe.

[0026] Comparative Example 2 An anti-aging cable protection tube, made from the following raw materials measured in parts by weight: 80 parts polypropylene, 15 parts SBS elastomer, 10 parts maleic anhydride-grafted polyethylene, 0.5 parts 3,5-bis(tert-butyl)-4-hydroxyphenylpropionyl chloride, 6 parts talc, 2.5 parts zinc stearate, 1 part UV absorber UV-P, and 1.5 parts 3-aminopropyltriethoxysilane. The method for preparing the cable protection pipe includes the following steps: Step 1: Weigh each raw material according to the specified weight proportions and prepare the materials. The second step involves adding all the raw materials to a high-speed mixer and mechanically mixing them at 110°C and a speed of 800 r / min. Then, the mixture is transferred to a twin-screw extruder, and the temperatures of each zone are controlled as follows: Zone 1 200°C, Zone 2 220°C, Zone 3 230°C, Zone 4 250°C, Zone 5 240°C, Zone 6 240°C, and the die temperature is 240°C. The mixture is then melt-extruded and granulated to obtain masterbatch. The masterbatch is then added to the hopper of a pipe extruder and extruded to form the cable protection pipe.

[0027] Comparative Example 3 An anti-aging cable protection tube, made from the following raw materials measured in parts by weight: 80 parts polypropylene, 15 parts SBS elastomer, 10 parts maleic anhydride-grafted polyethylene, 6 parts talc, 2.5 parts zinc stearate, 1 part UV absorber UV-P, and 1.5 parts 3-aminopropyltriethoxysilane. The method for preparing the cable protection pipe includes the following steps: Step 1: Weigh each raw material according to the specified weight proportions and prepare the materials. The second step involves adding all the raw materials to a high-speed mixer and mechanically mixing them at 110°C and a speed of 800 r / min. Then, the mixture is transferred to a twin-screw extruder, and the temperatures of each zone are controlled as follows: Zone 1 200°C, Zone 2 220°C, Zone 3 230°C, Zone 4 250°C, Zone 5 240°C, Zone 6 240°C, and the die temperature is 240°C. The mixture is then melt-extruded and granulated to obtain masterbatch. The masterbatch is then added to the hopper of a pipe extruder and extruded to form the cable protection pipe.

[0028] Performance testing The cable protection pipes in the examples and comparative examples were made into various test specimens that met the specifications, and performance tests were conducted. The test results are recorded in the table below: Table 1 - Test Results

[0029] The tensile strength test method refers to the standard GB / T 1040.2-2022. The tensile rate is set to 50 mm / min. After the test results are obtained, the samples of the same batch are stored at room temperature for one month, and then placed in a temperature environment of 120℃ for accelerated thermo-oxidative aging for 24 hours before testing the tensile strength. The impact strength test method refers to the standard GB / T 1843-2008.

[0030] Analysis of the test results shows that the cable protection pipe in the embodiment of the present invention has excellent mechanical properties and good anti-aging properties. After replacing the synergistic antioxidant with the single antioxidant MB or 3,5-bis(tert-butyl)-4-hydroxyphenylpropionyl chloride, on the one hand, migration and precipitation occur during storage, resulting in a reduction in the antioxidant content in the material. On the other hand, they cannot form a synergistic effect and cannot improve the structural density of the material. Therefore, the mechanical properties and anti-aging properties are both poor.

[0031] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are merely for the purpose of helping to understand the method and core ideas of the present invention, including the best mode, and also to enable any person skilled in the art to practice the present invention, including implementing any combination of methods. It should be noted that for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention. The scope of protection of this patent is defined by the claims and may include other embodiments that can be conceived by those skilled in the art. If these other embodiments have structural elements similar to the wording of the claims, or if they include equivalent structural elements that are not substantially different from the wording of the claims, then these other embodiments should also be included within the scope of the claims.

[0032] Based on the preferred embodiments of the present invention, and through the above description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. An anti-aging cable protection pipe, characterized in that, It is made from the following raw materials, measured in parts by weight: Polypropylene 75-95 parts, elastomer 10-20 parts, compatibilizer 5-15 parts, synergistic antioxidant 0.3-0.6 parts, inorganic additives 4-8 parts, lubricant 2-3 parts, ultraviolet absorber 0.5-1.5 parts, silane coupling agent 1-2 parts; The synergistic antioxidant is a macromolecular substance with alternating benzimidazole-hindered phenol block linkages.

2. The anti-aging cable protection pipe according to claim 1, characterized in that, The elastomer is at least one of TPU elastomer, SBS elastomer, or SEBS elastomer; the compatibilizer is maleic anhydride-grafted polyethylene or maleic anhydride-grafted polypropylene; the inorganic additive is talc, calcium carbonate, or fumed silica; the lubricant is calcium stearate, zinc stearate, or polyethylene wax; the ultraviolet absorber is any one of UV absorber UV-531, UV absorber UV-P, or UV absorber UV-9; and the silane coupling agent is 3-aminopropyltrimethoxysilane or 3-aminopropyltriethoxysilane.

3. The anti-aging cable protection pipe according to claim 1, characterized in that, The preparation method of the synergistic antioxidant is as follows: Add antioxidant MB derivative, hindered phenolic antioxidant derivative, and N,N-dimethylformamide to a nitrogen-filled reactor. After the addition is complete, start stirring. Once a homogeneous mixture is formed, continue adding catalyst to the reactor, then start heating. Control the heating rate at 3-5℃ / min to raise the temperature to 60-70℃. Hold the temperature for 2-4 hours, then further raise the temperature to 90-100℃. Continue stirring and holding the temperature for 16-24 hours. Stop heating, separate the solid material, and after washing and vacuum drying, the synergistic antioxidant can be obtained.

4. The anti-aging cable protection pipe according to claim 3, characterized in that, The preparation method of the antioxidant MB derivative is as follows: Antioxidant MB, 2-bromosuccinic acid and toluene are added to a reaction vessel. After the addition is complete, the mixture is stirred until homogeneous. Then, an acid-binding agent is added and stirred until homogeneous. The temperature is raised to 70-80℃ and kept at this temperature for 3-6 hours. The solvent is evaporated and removed, the material is cooled and discharged, and the product is collected to obtain the antioxidant MB derivative.

5. The anti-aging cable protection pipe according to claim 4, characterized in that, The molar ratio of the antioxidant MB to 2-bromosuccinic acid is 1:

1.

6. The anti-aging cable protection pipe according to claim 4, characterized in that, The acid-binding agent is potassium carbonate or sodium carbonate.

7. The anti-aging cable protection pipe according to claim 3, characterized in that, The method for preparing the hindered phenolic antioxidant derivative is as follows: Add 3,5-bis(tert-butyl)-4-hydroxyphenylpropionyl chloride to acetone and mix well. Then, under ice bath conditions, add 1,3-diepoxyglycerol ether glycerol and triethylamine to the mixture. After the addition is complete, remove the mixture from the ice bath and stir at room temperature for 2-3 hours. Evaporate to remove the solvent, cool down and discharge the product to obtain the hindered phenol antioxidant derivative.

8. The anti-aging cable protection pipe according to claim 7, characterized in that, The molar ratio of 3,5-bis(tert-butyl)-4-hydroxyphenylpropionyl chloride to 1,3-diepoxyglycerol ether glycerol is 1:

1.

9. The anti-aging cable protection pipe according to claim 3, characterized in that, The catalyst is any one of tetrabutylammonium bromide, tetramethylammonium bromide, tetrabutylammonium bisulfate, tetrabutylammonium chloride, or tetramethylammonium chloride.

10. A method for preparing an anti-aging cable protection pipe as described in claim 1, characterized in that, Includes the following steps: Step 1: Weigh each raw material according to the specified weight proportions and prepare the materials. The second step involves adding all raw materials to a high-speed mixer and mechanically mixing them at a temperature of 100-120℃ and a speed of 500-1000 r / min. Then, the mixture is transferred to a twin-screw extruder, and the temperatures of each zone are controlled as follows: Zone 1 200±5℃, Zone 2 220±5℃, Zone 3 230±5℃, Zone 4 250±5℃, Zone 5 240±5℃, Zone 6 240±5℃, and the die temperature is 240±5℃. The mixture is then melt-extruded and granulated to obtain masterbatch. The masterbatch is then added to the hopper of a pipe extruder and extruded to form the cable protection pipe.

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