A recyclable thermoplastic polypropylene cable insulation material and a method for producing the same

Abstract

The application discloses a recyclable thermoplastic polypropylene cable insulation material and a preparation method thereof, relates to the technical field of cable preparation, and comprises polypropylene, β A crystal nucleating agent and a composite antioxidant; wherein, β The crystal nucleating agent is a carboxylate nucleating agent; and the composite antioxidant comprises a main antioxidant and an auxiliary antioxidant. The metal ion of the carboxylate nucleating agent can generate strong ion-dipole interaction with a P=O bond in the molecule of the auxiliary antioxidant, thereby improving the relatively low inherent nucleating efficiency of the carboxylate, and significantly enhancing the long-term thermal stability of the composite antioxidant system, so that the material can resist thermal oxidative aging and maintain mechanical and electrical properties in long-term high-temperature operation. The cooperation between the main antioxidant and the auxiliary antioxidant can enable the material to remain stable in a long-term thermal history. The insulation material significantly improves the material toughness, heat aging resistance and comprehensive electrical insulation performance while maintaining the recyclable property, and has better application value.

Description

Technical Field

[0001] This invention relates to the field of cable manufacturing technology, and more specifically, to a recyclable thermoplastic polypropylene cable insulation material and its preparation method. Background Technology

[0002] Cross-linked polyethylene (XLPE) has long been the core insulation material for power cables due to its excellent overall performance. However, its thermosetting properties mean that waste cables cannot be melted down and recycled, and currently, disposal mainly relies on landfill or incineration, leading to serious environmental pressure and resource waste. Although technologies such as chemical recycling have been explored, they are difficult to scale up due to high costs, complex processes, or product degradation. Therefore, developing a recyclable and high-performance alternative insulation material is a key challenge that the cable industry urgently needs to solve.

[0003] Polypropylene (PP), as a thermoplastic material, has advantages such as melt recyclability, low production energy consumption, and high temperature resistance, and is considered a potential material to replace XLPE. However, the direct use of pure PP for cable insulation still has obvious defects: (1) poor toughness and high low-temperature brittleness, making it difficult to meet the mechanical requirements of cable laying and operation; (2) difficult to control crystallization behavior, high crystallinity leads to brittleness, and low crystallinity affects heat resistance and insulation strength; (3) tertiary carbon atoms in the molecular chain are prone to thermal oxidative aging, affecting long-term service life. Existing modification methods (such as elastomer blending, nanocomposite, etc.) often sacrifice other properties when improving one property, or introduce interface, dispersion and other problems, making it difficult to achieve a balanced improvement in toughness, insulation, aging resistance and recyclability.

[0004] Therefore, developing a polypropylene-based cable insulation material that combines excellent mechanical properties, good electrical insulation properties, heat and oxygen aging resistance, and is fully recyclable has significant engineering application value and environmental significance. Summary of the Invention

[0005] The purpose of this invention is to provide a recyclable thermoplastic polypropylene cable insulation material and its preparation method, so as to solve the technical problems of poor toughness, difficult crystallization behavior, insufficient thermo-oxidative aging performance, and non-recyclability of traditional XLPE insulation materials.

[0006] The embodiments of the present invention are implemented as follows: A recyclable thermoplastic polypropylene cable insulation material, comprising the following components by weight: 100 parts of polypropylene; β Crystal nucleating agent 0.05~2.0 parts; composite antioxidant 0.1~3.0 parts; in, βThe nucleating agent is a carboxylate nucleating agent; the composite antioxidant includes a primary antioxidant and a secondary antioxidant, the primary antioxidant being a hindered phenolic antioxidant and the secondary antioxidant being a phosphite antioxidant.

[0007] A method for preparing the above-mentioned thermoplastic polypropylene cable insulation material, comprising: Polypropylene, β A premix is ​​obtained by uniformly mixing a crystal nucleating agent and a composite antioxidant. The premixed material is melt-blended and extruded through an extruder, cooled, and pelletized to obtain thermoplastic polypropylene cable insulation material.

[0008] The beneficial effects of the embodiments of the present invention are: This invention provides a recyclable thermoplastic polypropylene cable insulation material and its preparation method, comprising polypropylene in a specific ratio, β Crystal nucleating agents and composite antioxidants; among which, β The nucleating agent is a carboxylate-based nucleating agent; the composite antioxidant includes a primary antioxidant and a secondary antioxidant. The metal ions of the carboxylate nucleating agent can generate strong ion-dipole interactions with the P=O bonds in the secondary antioxidant molecules, which not only improves the relatively low inherent nucleation efficiency of carboxylates but also significantly enhances the long-term thermal stability of the composite antioxidant system, enabling the material to resist thermo-oxidative aging and maintain its mechanical and electrical properties during long-term high-temperature operation. Simultaneously, the synergy between the primary and secondary antioxidants better ensures that the polypropylene matrix does not undergo chain breakage or cross-linking damage, allowing the nucleating agent-induced crystal formation to... β The crystalline structure remains stable over a long thermal history. This insulating material, while maintaining the fully recyclable nature of PP, significantly improves its toughness, heat aging resistance, and overall electrical insulation performance required for cable insulation, making it highly valuable for various applications. Detailed Implementation

[0009] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0010] The following is a detailed description of a recyclable thermoplastic polypropylene cable insulation material, its preparation method, and its application according to an embodiment of the present invention.

[0011] This invention provides a recyclable thermoplastic polypropylene cable insulation material, which, by weight, comprises the following components: 100 parts of polypropylene; βCrystal nucleating agent 0.05~2.0 parts; composite antioxidant 0.1~3.0 parts; in, β The nucleating agent is a carboxylate nucleating agent; the composite antioxidant includes a primary antioxidant and a secondary antioxidant, the primary antioxidant being a hindered phenolic antioxidant and the secondary antioxidant being a phosphite antioxidant.

[0012] Carboxylate nucleating agents are a low-cost type of nucleating agent. β Crystalline nucleating agents are used, but carboxylate nucleating agents suffer from problems such as low nucleation efficiency, difficulty in dispersion, and easy aggregation. When used alone, β The crystal content can only reach 60%~75%, and the nucleation efficiency is significantly lower than that of commonly used organic nucleating agents on the market, such as 2,6-naphthalenedicarboxylic acid cyclohexylamide (NU-100) and tetrahydrophthalic anhydride derivatives (such as TMB-5).

[0013] Commonly used antioxidants for polypropylene fall into two main categories: free radical scavengers and peroxide decomposers. Free radical scavengers primarily capture alkyl and alkoxy radicals generated during polypropylene degradation, thereby interrupting the chain reaction and preventing initial degradation. Peroxide decomposers primarily decompose hydroperoxides (ROOH) generated by the thermal oxidation of polypropylene into stable alcohols (ROH), thus preventing the generation of new free radicals. In existing technologies, these two types of antioxidants are often used in combination.

[0014] The primary antioxidant in this invention is a hindered phenolic antioxidant (e.g., antioxidant 1010, antioxidant 1076, etc.), and the secondary antioxidant is a phosphite antioxidant (e.g., antioxidant 168, antioxidant 626, etc.). The metal ions of the carboxylate nucleating agent (such as Ca in calcium stearate) are also present. 2+ It can generate strong ion-dipole interactions with the P=O bonds in auxiliary antioxidant molecules. This interaction acts as a molecular bridging mechanism. On one hand, it helps improve the dispersion of carboxylates in polypropylene melt, increases effective nucleation sites, and thus more effectively induces the formation of toughening agents. β The crystalline form overcomes the low-temperature brittleness of polypropylene. On the other hand, it anchors some of the auxiliary antioxidants at the nucleating agent interface region, delaying their migration and consumption. Through this mechanism, not only is the relatively low inherent nucleation efficiency of carboxylates improved, but the long-term thermal stability of the composite antioxidant system is also significantly enhanced, enabling the material to resist thermo-oxidative aging and maintain its mechanical and electrical properties during long-term high-temperature operation.

[0015] Building upon this foundation, the classic synergistic effect of composite antioxidants is retained. Hindered phenolic antioxidants capture free radicals by providing hydrogen atoms, while phosphite antioxidants decompose hydroperoxides, both blocking the oxidation chain reaction through different mechanisms. Simultaneously, the large sterically hindered groups of the hindered phenolic antioxidants severely weaken the interaction between their phenolic hydroxyl groups and the metal ions of the carboxylate nucleating agent, resulting in only weak coordination or ion-dipole interactions between the primary antioxidant and the carboxylate nucleating agent. This weak interaction slightly improves the dispersibility of the primary antioxidant in the polypropylene matrix without weakening the free radical capture ability of the phenolic hydroxyl groups, thus maximizing the antioxidant performance of the primary antioxidant.

[0016] Furthermore, β The mass ratio of nucleating agent, primary antioxidant, and secondary antioxidant is 1:0.5~1.5:0.2~1.2. Within this range, the secondary antioxidant can generate optimal ion-dipole interactions with the metal ions of the carboxylate through its P=O bonds. If the ratio is too low, the effect will be insufficient, failing to effectively improve the dispersion and stability of the carboxylate; if the ratio is too high, it will lead to oversaturation or self-aggregation of the secondary antioxidant molecules on the nucleating agent surface, thus interfering with the nucleation efficiency. Simultaneously, at the above ratio, the synergistic antioxidant performance of the primary and secondary antioxidants is better, providing durable and strong thermo-oxidative stability protection for the entire material, addressing the fundamental defect of polypropylene's susceptibility to thermo-oxidative aging.

[0017] The carboxylate nucleating agent is selected from at least one of fatty acid salts, aromatic carboxylates, and dicarboxylates. Preferably, the carboxylate nucleating agent is a calcium salt or an aluminum salt. More preferably, the carboxylate nucleating agent is at least one of calcium stearate, aluminum benzoate, calcium pimecrolate, or aluminum diethyl sebacate. These carboxylate nucleating agents have the advantages of low cost and wide availability.

[0018] Polypropylene is at least one of random copolymer polypropylene, block copolymer polypropylene, or isotactic homopolymer polypropylene.

[0019] Optionally, the thermoplastic polypropylene cable insulation material further includes 1 to 10 parts by weight of a toughening agent, wherein the toughening agent is at least one selected from styrene-ethylene-butene-styrene block copolymer, styrene-butadiene block copolymer, or ethylene-octene copolymer. The addition of these elastomer toughening agents can significantly improve the material's impact resistance, environmental stress cracking resistance, and flexibility, making the insulation material more resistant to mechanical stresses such as bending and compression during installation, thus broadening its application scenarios.

[0020] Optionally, the thermoplastic polypropylene cable insulation material further includes 1 to 20 parts by weight of a filler, wherein the filler is at least one selected from talc, calcium carbonate, or wollastonite. The filler can further reduce raw material costs and improve the material's rigidity, hardness, and dimensional stability.

[0021] Optionally, the thermoplastic polypropylene cable insulation material further includes 0.1 to 1 part by weight of a lubricant, wherein the lubricant is at least one of silicone or polypropylene wax. The lubricant can improve processing fluidity, reduce friction between the melt and processing equipment, thereby reducing processing energy consumption, increasing extrusion speed, improving the surface finish of the product, and aiding in the dispersion of the components.

[0022] This invention also provides a method for preparing the above-mentioned thermoplastic polypropylene cable insulation material, comprising: Polypropylene, β A premix is ​​obtained by uniformly mixing a crystal nucleating agent and a composite antioxidant. The premixed material is melt-blended and extruded through an extruder, cooled, and pelletized to obtain thermoplastic polypropylene cable insulation material.

[0023] Furthermore, the extruder barrel temperature is set as follows: Zone 1: 160~180℃, Zone 2: 180~200℃, Zone 3: 190~210℃, Zone 4: 200~220℃, Zone 5: 200~220℃, Die head temperature: 200~215℃, Screw speed: 150~400rpm.

[0024] Under these conditions, it is ensured that the polypropylene is fully melted, and that all additives are well dispersed and function effectively, while avoiding excessive temperature that could lead to thermal degradation of the polypropylene and antioxidants. The screw speed is used to provide sufficient shear force to ensure that trace components such as nucleating agents and antioxidants are more uniformly dispersed in the polypropylene matrix.

[0025] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0026] Example 1

[0027] This embodiment provides a recyclable thermoplastic polypropylene cable insulation material, which, by weight, comprises the following components: Polypropylene resin: 100 parts. Random copolymer polypropylene with an ethylene content of 3 wt.% was selected. β Crystal nucleating agent: 0.5 parts. Calcium stearate is selected.

[0028] Main antioxidant: 0.5 parts. Antioxidant 1010 is selected.

[0029] Auxiliary antioxidant: 0.3 parts. Antioxidant 168 is selected.

[0030] Its preparation method is as follows: S1. Mixing: Mix all the above raw materials in a high-speed mixer at room temperature and 500 rpm for 5 minutes to obtain a premix.

[0031] S2. Melt Blending and Granulation: The premixed material is added to a twin-screw extruder. The temperatures of each section of the extruder are set as follows: Zone 1 170℃, Zone 2 190℃, Zone 3 200℃, Zone 4 210℃, Zone 5 210℃, and the die head temperature is 210℃. The screw speed is 300 rpm. The melt-extruded material is cooled in a 30℃ water bath, air-dried, and then granulated to obtain the thermoplastic polypropylene cable insulation material granules.

[0032] Example 2

[0033] This embodiment provides a recyclable thermoplastic polypropylene cable insulation material, which, by weight, comprises the following components: Polypropylene resin: 100 parts. Isotactic homopolymer polypropylene is selected.

[0034] β Crystal nucleating agent: 1.0 part. Aluminum benzoate is selected.

[0035] Main antioxidant: 0.8 parts. Antioxidant 1076 was selected.

[0036] Auxiliary antioxidant: 0.24 parts. Antioxidant 168 is selected.

[0037] Its preparation method is as follows: S1. Mixing: Mix all the above raw materials in a high-speed mixer at room temperature and 500 rpm for 5 minutes to obtain a premix.

[0038] S2. Melt Blending and Granulation: The premixed material is added to a twin-screw extruder. The extruder temperatures are set as follows: Zone 1 180℃, Zone 2 200℃, Zone 3 210℃, Zone 4 220℃, Zone 5 220℃, and the die head temperature 215℃. The screw speed is 300 rpm. The melt-extruded material is cooled in a 30℃ water bath, air-dried, and then granulated to obtain the thermoplastic polypropylene cable insulation material granules.

[0039] Example 3

[0040] This embodiment provides a recyclable thermoplastic polypropylene cable insulation material, which, by weight, comprises the following components: Polypropylene resin: 100 parts. Random copolymer polypropylene with an ethylene content of 5 wt.% was selected.

[0041] β Crystal nucleating agent: 0.2 parts. Calcium stearate is selected.

[0042] Main antioxidant: 0.3 parts. Antioxidant 1010 is selected.

[0043] Auxiliary antioxidant: 0.24 parts. Antioxidant 168 is selected.

[0044] Toughening agent: 5 parts. Styrene-ethylene-butene-styrene block copolymer is selected.

[0045] Filler: 10 parts. Use 1250 mesh talc powder.

[0046] Lubricant: 0.3 parts. Silicone is preferred.

[0047] Its preparation method is as follows: S1. Mixing: Mix all the above raw materials in a high-speed mixer at room temperature and 500 rpm for 5 minutes to obtain a premix.

[0048] S2. Melt Blending and Granulation: The premixed material is added to a twin-screw extruder. The temperatures of each section of the extruder are set as follows: Zone 1 170℃, Zone 2 190℃, Zone 3 200℃, Zone 4 210℃, Zone 5 210℃, and the die head temperature is 210℃. The screw speed is 300 rpm. The melt-extruded material is cooled in a 30℃ water bath, air-dried, and then granulated to obtain the thermoplastic polypropylene cable insulation material granules.

[0049] Comparative Example 1 This comparative example provides a recyclable thermoplastic polypropylene cable insulation material, which is essentially the same as that in Example 1, except that... β The crystal nucleating agent was replaced by an equal mass of N,N-dicyclohexyl-2,6-naphthalenediamide instead of calcium stearate.

[0050] Comparative Example 2 This comparative example provides a recyclable thermoplastic polypropylene cable insulation material, which is basically the same as that in Example 1, except that the auxiliary antioxidant is removed and only the main antioxidant is retained.

[0051] Comparative Example 3 This comparative example provides a recyclable thermoplastic polypropylene cable insulation material, which is basically the same as that in Example 1, except that the primary antioxidant is removed and only the secondary antioxidant is retained.

[0052] Test case The thermoplastic polypropylene cable insulation materials prepared in Examples 1-3 and Comparative Examples 1-3, as well as commercially available XLPE, were used as controls to test the performance of each sample. The test methods are as follows: (1) Tensile properties: Tested according to GB / T1040-2018 standard, tensile speed 50mm / min, test temperature 23℃.

[0053] (2) Elongation at break retention rate (thermal aging performance): According to GB / T2951.12-2008 standard, thermal aging test was carried out in an oven at 135°C. The elongation at break after different aging times (7 days, 14 days, 28 days, 42 days, 56 days) was tested, and the retention rate (elongation after aging / initial elongation × 100%) was calculated.

[0054] (3) Volume resistivity: Tested according to GB / T1410-2006 standard, with test temperatures of 20℃, 70℃, 90℃ and 105℃ respectively.

[0055] (4) Dielectric strength: Tested according to GB / T1408.1-2016 standard, using power frequency AC voltage, with a step-up rate of 2kV / s.

[0056] (5) Melting and crystallization behavior: Differential scanning calorimetry (DSC) was used to test the melting temperature and crystallinity at a heating rate of 10℃ / min under nitrogen atmosphere.

[0057] The test results are shown in Table 1.

[0058] Table 1. Comparison of the performance of cable insulation materials Tensile strength (MPa) 28.5 30.8 34.2 25.7 22.4 19.1 23.5 Elongation at break (%) 580 520 550 530 380 280 520 Elongation retention rate after 56 days of heat aging (%) 91 85 81 63 25 18 75 Volume resistivity (20℃, Ω·m) <![CDATA[8.5×10 15 ]]> <![CDATA[7.2×10 15 ]]> <![CDATA[8.8×10 15 ]]> <![CDATA[3.8×10 15 ]]> <![CDATA[1.4×10 15 ]]> <![CDATA[2.0×10 14 ]]> <![CDATA[3.2×10 15 ]]> Volume resistivity (105℃, Ω·m) <![CDATA[3.2×10 14 ]]> <![CDATA[2.8×10 14 ]]> <![CDATA[3.5×10 14 ]]> <![CDATA[1.8×10 14 ]]> <![CDATA[8.5×10 13 ]]> <![CDATA[8.0×10 12 ]]> <![CDATA[1.5×10 14 ]]> Dielectric strength (kV / mm) 32.5 31.2 33.1 30.1 28.4 23.6 29.5 Crystallinity (%) 34.5 32.8 35.2 36.0 27.5 25.1 - Relative content of β-phase (%) 86 83 85 82 53 64 - As shown in Table 1, the thermoplastic polypropylene cable insulation materials provided in Examples 1-3 of this invention exhibit excellent mechanical properties. Their tensile strength and elongation at break have reached or exceeded those of commercially available XLPE, and after heat aging tests, the elongation at break retention rate is extremely high, exceeding 81%. Furthermore, their volume resistivity at both room temperature and high temperature is superior to XLPE, demonstrating better electrical insulation stability. β Regarding crystal nucleation efficiency and structure control, Examples 1-3 β The relative content of the crystalline phase is relatively high, reaching 83%~86%. The combination of its carboxylate nucleating agent and composite antioxidant shows a better ability to induce and control the crystal morphology of polypropylene.

[0059] In contrast, Comparative Example 1 replaced carboxylate nucleating agents with organic nucleating agents, and the nucleating agents lacked strong specific interactions with the antioxidants. β The relative content of the crystalline phase is only 75%. It is evident that the embodiments of this invention utilize the strong interaction between carboxylate nucleating agents and antioxidants, employing lower-cost carboxylate nucleating agents, and achieving results that even surpass those of organic nucleating agents. This is more conducive to large-scale industrial production. Simultaneously, the elongation retention rate after heat aging in the comparative example is significantly reduced to 63%, and the volume resistivity at 105°C decreases to 1.8 × 10⁻⁶. 14The Ω·m indicates that the material's thermal and oxygen stability has deteriorated, which also proves that the strong interaction between the carboxylate nucleating agent and the antioxidant in this invention has a significant effect on improving the overall antioxidant capacity of the material.

[0060] Comparative Examples 2 and 3 investigated the cases of removing the auxiliary antioxidant and removing the primary antioxidant, respectively. The most significant impacts were observed on elongation retention after 56 days of heat aging and volume resistivity at high temperatures, indicating that the absence of antioxidants accelerated oxidative degradation and significant aging of the material. Furthermore, the absence of antioxidants also affected… β The formation of the crystal phase also has a significant impact, especially in the absence of auxiliary antioxidants. β The relative content of the crystalline phase even decreased to 53%. This shows that the presence of antioxidants is also... β The key factors for achieving a high nucleation rate in crystal phases.

[0061] In summary, the embodiments of the present invention provide a recyclable thermoplastic polypropylene cable insulation material and a method for preparing the same, comprising polypropylene in a specific ratio, β Crystal nucleating agents and composite antioxidants; among which, β The nucleating agent is a carboxylate-based nucleating agent; the composite antioxidant includes a primary antioxidant and a secondary antioxidant. The metal ions of the carboxylate nucleating agent can generate strong ion-dipole interactions with the P=O bonds in the secondary antioxidant molecules, which not only improves the relatively low inherent nucleation efficiency of carboxylates but also significantly enhances the long-term thermal stability of the composite antioxidant system, enabling the material to resist thermo-oxidative aging and maintain its mechanical and electrical properties during long-term high-temperature operation. Simultaneously, the synergy between the primary and secondary antioxidants better ensures that the polypropylene matrix does not undergo chain breakage or cross-linking damage, allowing the nucleating agent-induced crystal formation to... β The crystalline structure remains stable over a long thermal history. This insulating material, while maintaining the fully recyclable nature of PP, significantly improves its toughness, heat aging resistance, and overall electrical insulation performance required for cable insulation, making it highly valuable for various applications.

[0062] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A recyclable thermoplastic polypropylene cable insulation material, characterized in that, By weight, it includes the following components: 100 parts of polypropylene; β Crystal nucleating agent 0.05~2.0 parts; composite antioxidant 0.1~3.0 parts; Among them, the β The nucleating agent is a carboxylate nucleating agent; the composite antioxidant includes a primary antioxidant and a secondary antioxidant, wherein the primary antioxidant is a hindered phenolic antioxidant and the secondary antioxidant is a phosphite antioxidant.

2. The recyclable thermoplastic polypropylene cable insulation material according to claim 1, characterized in that, The β The mass ratio of the nucleating agent, the primary antioxidant, and the secondary antioxidant is 1:0.5~1.5:0.2~1.

2.

3. The recyclable thermoplastic polypropylene cable insulation material according to claim 1, characterized in that, The carboxylate nucleating agent is selected from at least one of fatty acid salts, aromatic carboxylate salts, and dicarboxylate salts.

4. The recyclable thermoplastic polypropylene cable insulation material according to claim 3, characterized in that, The carboxylate nucleating agent is at least one of calcium stearate, aluminum benzoate, calcium pimecronate, or aluminum diethyl sebacate.

5. The recyclable thermoplastic polypropylene cable insulation material according to claim 1, characterized in that, The polypropylene is at least one of random copolymer polypropylene, block copolymer polypropylene, or isotactic homopolymer polypropylene.

6. The recyclable thermoplastic polypropylene cable insulation material according to claim 1, characterized in that, It also includes 1 to 10 parts by weight of a toughening agent, wherein the toughening agent is at least one of styrene-ethylene-butene-styrene block copolymer, styrene-butadiene block copolymer or ethylene-octene copolymer.

7. The recyclable thermoplastic polypropylene cable insulation material according to claim 1, characterized in that, It also includes 1 to 20 parts by weight of a filler, wherein the filler is at least one of talc, calcium carbonate or wollastonite.

8. The recyclable thermoplastic polypropylene cable insulation material according to claim 1, characterized in that, It also includes 0.1 to 1 part by weight of a lubricant, wherein the lubricant is at least one of silicone or polypropylene wax.

9. A method for preparing the thermoplastic polypropylene cable insulation material as described in any one of claims 1 to 8, characterized in that, include: The polypropylene, the β A crystal nucleating agent, wherein the composite antioxidant is mixed evenly to obtain a premix; The premixed material is melt-blended and extruded through an extruder, cooled, and pelletized to obtain the thermoplastic polypropylene cable insulation material.

10. The preparation method according to claim 9, characterized in that, The barrel temperature of the extruder is set as follows: Zone 1: 160~180℃, Zone 2: 180~200℃, Zone 3: 190~210℃, Zone 4: 200~220℃, Zone 5: 200~220℃, Die head temperature: 200~215℃, Screw speed: 150~400rpm.