Waterproof corrosion-resistant cable material, preparation method thereof and cable

Abstract

The invention relates to the technical field of power cable materials, and particularly discloses a waterproof corrosion-resistant cable material, a preparation method thereof and a cable. The waterproof corrosion-resistant cable material is prepared from the following raw materials: 55 to 75 parts of a modified polyethylene-polyvinyl chloride blend, 5 to 10 parts of an aminated graphene / montmorillonite intercalation composite material, 5 to 15 parts of acrylate rubber, 1 to 3 parts of carbon nanotubes, 2 to 4 parts of nano zinc oxide, 1 to 2 parts of an antioxidant, 0.5 to 1.5 parts of a lubricant, 3 to 6 parts of a plasticizer and 2 to 5 parts of a compatilizer, the modified polyethylene-polyvinyl chloride blend is obtained by carrying out cross-linking modification on a polyethylene-polyvinyl chloride blend by using zinc dithiocarbamate. The cable material disclosed by the invention has excellent waterproof performance and corrosion resistance, and the application scene of the cable material is obviously expanded.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power cable materials, more particularly, it relates to a waterproof and corrosion-resistant cable material, a preparation method thereof and a cable. BACKGROUND

[0002] As the core medium for power transmission and signal transmission, cables play an indispensable role in many fields such as modern industrial production, construction engineering, infrastructure construction, etc. As a key component for wrapping the internal conductor of the cable and isolating the external environment, the cable material not only needs to have excellent insulation performance and mechanical strength to ensure the safety of power transmission, but also needs to have good environmental adaptability to resist the erosion of external complex working conditions, which is one of the core factors determining the service life and reliability of the cable.

[0003] At present, the cable materials used in the industry are mainly general plastics such as polyvinyl chloride and polyethylene, and high-performance materials such as fluoroplastic and silicone rubber are used in some special scenarios. Among them, polyethylene has become the mainstream choice of cable materials due to its excellent insulation, good mechanical strength and relatively low cost; polyvinyl chloride has more applications in medium and low voltage cables due to its simple processing technology and high cost performance; and high-performance materials such as fluoroplastic and silicone rubber are mainly used in special cables under extreme conditions due to their excellent environmental resistance.

[0004] However, the existing mainstream cable materials have obvious shortcomings in water resistance and corrosion resistance, which cannot meet the long-term use requirements in complex and harsh environments. Taking the most widely used polyethylene material as an example, although it has certain hydrophobicity, there are defects in the crystalline region and free volume in the non-crystalline region of the molecular structure. In a humid environment or long-term immersion working condition, water molecules can easily penetrate into the material through these channels, not only causing a significant decrease in material insulation performance, but also possibly causing a "water tree" phenomenon, accelerating the aging and failure of the cable; when in contact with corrosive media such as acid, alkali and salt mist, the material surface will slowly deteriorate, and long-term effects will cause swelling, cracking and other problems, greatly reducing the protective effect of the sheath. For polyvinyl chloride materials, the chlorine element contained in the molecular chain is prone to hydrolysis reaction in a humid environment, causing the material surface to bulge, become brittle and crack, further exacerbating water penetration and corrosion of corrosive media. The above-mentioned defects in water resistance and corrosion resistance make the cable service life significantly shortened when serving in a humid and corrosive environment, which can easily cause power transmission failures and even safety hazards. SUMMARY

[0005] In order to effectively enhance the water resistance and corrosion resistance of the cable material, the present application provides a waterproof and corrosion-resistant cable material, a preparation method thereof and a cable.

[0006] The waterproof and corrosion-resistant cable material provided in this application adopts the following technical solution: A waterproof and corrosion-resistant cable material, comprising the following raw materials in parts by weight: 55-75 parts of modified polyethylene-polyvinyl chloride blend; 5-10 parts of amino-based graphene / montmorillonite intercalation composite material; 5-15 parts of acrylic rubber; 1-3 parts carbon nanotubes; 2-4 parts of nano zinc oxide; 1-2 parts antioxidant; 0.5-1.5 parts lubricant; 3-6 parts plasticizer; 2-5 parts compatibilizer; The modified polyethylene-polyvinyl chloride blend was obtained by crosslinking the polyethylene-polyvinyl chloride blend with zinc dithiocarbamate.

[0007] By adopting the above technical solutions, traditional polyethylene is prone to water molecule penetration due to defects in its crystalline regions and the free volume of its amorphous regions, while polyvinyl chloride (PVC) is prone to hydrolysis and embrittlement due to the presence of chlorine atoms. This solution uses zinc dithiocarbamate (ZDTC) as a dynamic crosslinking agent to modify polyethylene-PVC blends, forming a dynamic crosslinking network. On the one hand, the dynamic crosslinking bonds can effectively fill the crystalline defects and free volume of the amorphous regions in polyethylene, significantly reducing water molecule penetration channels and improving waterproof performance from the matrix structure. On the other hand, the crosslinking network can bind the PVC molecular chains, reducing the activity of chlorine atoms. Simultaneously, the reversibility of the dynamic crosslinking bonds can alleviate the internal stress generated during PVC hydrolysis, preventing material embrittlement and cracking, and improving hydrolysis and corrosion resistance.

[0008] Traditional montmorillonite single-layer intercalation modification has limited effect, while graphene, although having excellent barrier properties, is prone to aggregation. This solution employs amination modification to impart amino active groups to the graphene surface, enabling strong interactions between the graphene and montmorillonite sheets. This achieves uniform intercalation and dispersion of graphene within the montmorillonite sheets, forming a dual-barrier structure of "graphene-montmorillonite": First, this intercalation structure constructs a continuous three-dimensional barrier network within the material, creating a physical barrier against water molecules and corrosive media (acids, alkalis, and salt ions), preventing their penetration into the material. Second, the amino groups on the surface of the amination-modified graphene can form hydrogen bonds with the polar groups of the modified polyethylene-polyvinyl chloride blend, enhancing the compatibility of the intercalated composite material with the matrix and preventing performance degradation due to filler agglomeration. Third, the high specific surface area and excellent chemical stability of graphene enhance the material's chemical resistance to corrosive media, reducing the erosion of the matrix by the media. Simultaneously, the layered structure of montmorillonite further slows down the diffusion rate of corrosive media. Together, these two elements synergistically achieve a dual corrosion resistance effect of "physical barrier + chemical resistance."

[0009] Furthermore, the modified polyethylene-polyvinyl chloride blend provides a stable dispersion carrier for the intercalated composite material, ensuring that the intercalated composite material is uniformly dispersed in the matrix and avoiding the breakage of the barrier network. The three-dimensional barrier network of the intercalated composite material can further seal the tiny gaps that may exist in the dynamic cross-linking network. The two form a dual waterproof and corrosion-resistant system of "matrix densification + external barrier", which synergistically improves waterproof and corrosion-resistant performance. This effectively solves the pain points of existing technologies where waterproof and corrosion-resistant performance are difficult to balance and the material performance is unbalanced after modification. It significantly expands the application scenarios of cable materials, especially suitable for harsh environments with humid and corrosive media.

[0010] Optionally, the modified polyethylene-polyvinyl chloride blend is prepared by the following method: High-density polyethylene and polyvinyl chloride are added to a mixer and mixed at 160-170°C for 10-15 minutes. Then zinc dithiocarbamate is added and the mixture is mixed for another 8-12 minutes. Triallyl isocyanurate is then added and the mixture is further mixed at 170-180°C for 5-8 minutes. After cooling, the mixture is pulverized and passed through a 100-mesh sieve to obtain a modified polyethylene-polyvinyl chloride blend.

[0011] By employing the above-mentioned technical solution, the staged temperature-controlled mixing method achieves precise control of the dynamic crosslinking reaction, ensuring the performance stability of the modified matrix. This process first thoroughly mixes high-density polyethylene and polyvinyl chloride at a suitable temperature to ensure uniform compatibility. Then, by adding zinc dithiocarbamate and triallyl isocyanurate in steps, the progress and network density of the crosslinking reaction are controlled, avoiding the problem of excessive or insufficient crosslinking caused by concentrated addition of crosslinking agents. This staged mixing process enables the crosslinking bonds to be evenly distributed in the blend's molecular chains, further optimizing the filling effect of the dynamic crosslinking network on polyethylene crystal defects and its binding effect on polyvinyl chloride molecular chains, thereby improving the waterproof and hydrolysis-resistant properties of the matrix, while ensuring that the modified blend has good pulverability and compatibility with subsequent processing.

[0012] Optionally, the molecular weight of the high-density polyethylene is 150,000 to 300,000; the mass ratio of the high-density polyethylene to polyvinyl chloride is 1:(1.5-2).

[0013] By adopting the above technical solution, limiting the molecular weight range of high-density polyethylene and its mass ratio with polyvinyl chloride, the compatibility and cross-linking effect of the matrix blend were further optimized, laying the foundation for improving the waterproof and corrosion-resistant performance of the material. High-density polyethylene within a specific molecular weight range has suitable crystallinity and molecular chain entanglement. When blended with polyvinyl chloride in a specific ratio, it can form a structurally uniform blend system, reducing interface defects caused by poor component compatibility and preventing water molecules and corrosive media from penetrating and accumulating at the interface. A reasonable mass ratio can balance the performance advantages of both, retaining the excellent insulation and hydrophobicity of polyethylene while utilizing the mechanical strength of polyvinyl chloride. Simultaneously, dynamic cross-linking modification compensates for the respective shortcomings in waterproof and corrosion resistance of both, giving the modified matrix superior overall performance.

[0014] Optionally, the amount of zinc dithiocarbamate added is 3%-6% of the total mass of high-density polyethylene and polyvinyl chloride; the amount of triallyl isocyanurate added is 1%-3% of the total mass of high-density polyethylene and polyvinyl chloride.

[0015] Optionally, the aminated graphene / montmorillonite intercalation composite material is prepared by the following method: A1. Add graphene powder to a mixed acid and ultrasonically oxidize at 50-60℃ for 4-6 hours. After washing until neutral, add hydrazine hydrate and reduce at 90-100℃ for 6-8 hours to obtain reduced graphene oxide. Then, add the reduced graphene oxide and 3-aminopropyltriethoxysilane to an aqueous ethanol solution and reflux at 70-80℃ for 8-10 hours. After filtration and drying, obtain aminographene. A2. Disperse montmorillonite in deionized water to prepare a suspension with a mass fraction of 8-12%. Add aminated graphene and stir at 60-70℃ for 2-3 hours. Then add hexadecyltrimethylammonium bromide at 5-8% mass of montmorillonite and continue stirring for 3-5 hours. After filtration and washing, dry under vacuum at 110-120℃ for 10-12 hours. Grind through a 300-mesh sieve to obtain an aminated graphene / montmorillonite intercalation composite material.

[0016] By employing the above-mentioned technical solution, a two-step method of oxidation-reduction-ammoniation modification and intercalation composite is used to solve the technical problems of easy graphene agglomeration and limited barrier effect of montmorillonite alone. Step A1 prepares reduced graphene oxide by oxidation with mixed acid and reduction with hydrazine hydrate, followed by amination modification with a silane coupling agent to impart active amino groups to the graphene surface, enhancing its interaction with montmorillonite. Step A2 achieves uniform dispersion of graphene among montmorillonite sheets through montmorillonite suspension dispersion, aminated graphene intercalation, and modification with hexadecyltrimethylammonium bromide, forming a stable "graphene-montmorillonite" dual barrier structure. This preparation method can enhance the structural stability and compatibility of the intercalated composite material with the matrix, ensuring the construction of a continuous and complete three-dimensional barrier network within the material, effectively improving the physical barrier effect against water molecules and corrosive media, and strengthening the waterproof and corrosion-resistant properties of the material.

[0017] Optionally, in step A1, the mixed acid is concentrated nitric acid and concentrated sulfuric acid in a mass ratio of 1:(3-4); the amount of 3-aminopropyltriethoxysilane added is 15%-25% of the mass of the reduced graphene oxide.

[0018] By adopting the above technical solution, the preparation effect of aminated graphene was optimized, further improving the barrier performance of the intercalated composite material. A specific ratio of mixed acids can achieve moderate oxidation of graphene, introducing an appropriate amount of oxygen-containing functional groups onto its surface, providing sufficient active sites for subsequent amination modification, while avoiding excessive oxidation that could lead to graphene structural damage and decreased barrier performance. A reasonable amount of silane coupling agent ensures sufficient amino groups are grafted onto the graphene surface, enhancing its interaction with montmorillonite sheets, improving the intercalation composite effect, and simultaneously ensuring hydrogen bonding between the intercalated composite material and the matrix, preventing filler agglomeration and defects, thereby strengthening the synergistic effect of waterproofing and corrosion resistance.

[0019] Optionally, the antioxidant is at least one of antioxidant 1010, antioxidant 1035, and antioxidant 168.

[0020] Secondly, this application provides a method for preparing a waterproof and corrosion-resistant cable material, which adopts the following technical solution: A method for preparing a waterproof and corrosion-resistant cable material includes the following steps: S1. Mix and stir the modified polyethylene-polyvinyl chloride blend, aminated graphene / montmorillonite intercalation composite material, acrylate rubber, carbon nanotubes, nano zinc oxide, antioxidant, lubricant, plasticizer and compatibilizer for 8-12 minutes to obtain the mixture. S2. Add the mixture to a twin-screw extruder and melt-blend at 160-190℃ and 90-120MPa pressure for 1-2 hours. Then, extrude the mixture through a die and cool and solidify it to obtain a waterproof and corrosion-resistant cable material.

[0021] By adopting the above technical solution, the process first mixes and stirs all raw materials to ensure that the functional fillers, auxiliary agents and modified matrix are uniformly mixed, avoiding uneven performance caused by local component enrichment or deficiency; then, melt blending is carried out under appropriate temperature and pressure, which can ensure that the modified matrix is ​​fully melted, so that the dynamic cross-linking network and the barrier network of the intercalated composite material are tightly combined to form a synergistic protection system of "matrix densification + external barrier", and avoid material degradation and cross-linking network damage caused by excessive temperature or pressure, ensuring that the final product has stable and excellent waterproof and corrosion-resistant properties, while ensuring the smoothness of the extrusion molding process and the dimensional stability of the product.

[0022] Thirdly, this application provides a waterproof and corrosion-resistant cable, which adopts the following technical solution: A waterproof and corrosion-resistant cable uses the aforementioned waterproof and corrosion-resistant cable material as its sheath layer and / or insulation layer.

[0023] By using the cable material with excellent waterproof and corrosion-resistant properties as described in this application to prepare the sheath and / or insulation layers, a continuous protective barrier can be formed on the outside of the cable, effectively blocking the penetration of water molecules and corrosive media, and avoiding problems such as conductor oxidation and decreased insulation performance. At the same time, the excellent comprehensive performance of the material can ensure the mechanical strength and structural stability of the insulation and sheath layers, extend the service life of the cable, improve the operational safety and reliability of the cable in humid and corrosive environments, and expand the application range of the cable.

[0024] In summary, this application has the following beneficial effects: 1. This application utilizes zinc dithiocarbamate to dynamically crosslink polyethylene-polyvinyl chloride blends to obtain a modified matrix, which specifically addresses the core defect of poor waterproof and corrosion-resistant performance in traditional polyethylene and polyvinyl chloride materials. The dynamic crosslinking network effectively fills the crystalline defects and amorphous free volumes in the polyethylene molecular chains, significantly reducing water molecule penetration channels and improving waterproof performance at the matrix structure level, thus preventing aging failure caused by the "water tree" phenomenon. Simultaneously, the crosslinking network binds the polyvinyl chloride molecular chains, reducing the activity of chlorine atoms and alleviating the accumulation of internal stress during hydrolysis, preventing corrosion failure phenomena such as bulging, embrittlement, and cracking. Furthermore, the reversibility of the dynamic crosslinking bonds ensures good processing fluidity and flexibility, overcoming the drawbacks of decreased processing performance caused by traditional static crosslinking modification, and achieving a synergistic balance between waterproof and corrosion-resistant performance and processing performance.

[0025] 2. The preferred aminated graphene / montmorillonite intercalated composite material of this application effectively solves the technical pain points of limited barrier effect of traditional single montmorillonite and easy agglomeration of graphene, further enhancing the waterproof and corrosion-resistant performance of the material. Through oxidation-reduction-amination modification and intercalation composite process, graphene can be uniformly dispersed between montmorillonite sheets to form a stable double barrier structure, constructing a continuous three-dimensional barrier network inside the material, forming a highly efficient physical barrier against water molecules and corrosive media such as acids, alkalis, and salt spray, delaying their diffusion into the material interior. At the same time, the active groups on the surface of aminated graphene can form hydrogen bonds with the polar groups of the modified matrix, improving the compatibility between the filler and the matrix and avoiding agglomeration that generates new defects; the excellent chemical stability of graphene and the layered structure of montmorillonite work synergistically to achieve dual protection of "physical barrier + chemical resistance", significantly enhancing the material's resistance to corrosive media.

[0026] 3. The preparation method and cable products based on this material ensure stable performance in terms of waterproofing and corrosion resistance and expand application scenarios. During the preparation process, staged temperature-controlled mixing, gradient mixing, and precise control of melt blending parameters ensure uniform dispersion of each component. This allows the dynamic cross-linked network and the barrier network of the intercalated composite material to tightly bond, forming a synergistic protection system of "matrix densification + external barrier," avoiding imbalances in protective performance due to uneven component dispersion. Cable sheaths and / or insulation layers prepared using this material form a continuous protective barrier, effectively preventing the penetration of water molecules and corrosive media, and avoiding problems such as conductor oxidation and decreased insulation performance. Simultaneously, the material's excellent comprehensive properties ensure the mechanical strength and stability of the cable structure, significantly extending the cable's service life in harsh environments with humid and corrosive media, improving operational safety and reliability, and expanding the cable's application range. Detailed Implementation

[0027] The present application will be further described in detail below with reference to the embodiments.

[0028] Preparation example of modified polyethylene-polyvinyl chloride blend Preparation Example 1 The modified polyethylene-polyvinyl chloride blend was prepared by the following method: 10 kg of high-density polyethylene (molecular weight 150,000) and 15 kg of polyvinyl chloride were added to a mixer and mixed at 160°C for 15 min. Then, 0.75 kg of zinc dithiocarbamate was added and the mixture was mixed for another 8 min. Subsequently, 0.25 kg of triallyl isocyanurate was added and the mixture was further mixed at 170°C for 8 min. After cooling, the mixture was pulverized and passed through a 100-mesh sieve to obtain a modified polyethylene-polyvinyl chloride blend.

[0029] Preparation Example 2 The modified polyethylene-polyvinyl chloride blend was prepared by the following method: 10 kg of high-density polyethylene (molecular weight 200,000) and 18 kg of polyvinyl chloride were added to a mixer and mixed at 165°C for 12 min. Then, 1.26 kg of zinc dithiocarbamate was added and the mixture was mixed for another 10 min. Subsequently, 0.56 kg of triallyl isocyanurate was added and the mixture was further mixed at 175°C for 6 min. After cooling, the mixture was pulverized and passed through a 100-mesh sieve to obtain a modified polyethylene-polyvinyl chloride blend.

[0030] Preparation Example 3 The modified polyethylene-polyvinyl chloride blend was prepared by the following method: 10 kg of high-density polyethylene (molecular weight 300,000) and 20 kg of polyvinyl chloride were added to a mixer and mixed at 170°C for 10 min. Then, 1.8 kg of zinc dithiocarbamate was added and the mixture was mixed for another 15 min. Subsequently, 0.9 kg of triallyl isocyanurate was added and the mixture was further mixed at 180°C for 8 min. After cooling, the mixture was pulverized and passed through a 100-mesh sieve to obtain a modified polyethylene-polyvinyl chloride blend.

[0031] Preparation example of aminated graphene / montmorillonite intercalated composite material Preparation Example 4 The aminated graphene / montmorillonite intercalated composite material was prepared by the following method: A1. Add 10 kg of graphene powder to 100 kg of mixed acid, which is concentrated nitric acid and concentrated sulfuric acid in a mass ratio of 1:3. Oxidize at 50 °C for 4 h. After washing until neutral, add 2 kg of hydrazine hydrate and reduce at 90 °C for 6 h to obtain reduced graphene oxide. Then add 10 kg of reduced graphene oxide and 1.5 kg of 3-aminopropyltriethoxysilane to 80 kg of 40% ethanol aqueous solution. Reflux at 70 °C for 8 h. After filtration and drying, obtain aminographene. A2. Disperse 80 kg of montmorillonite in deionized water to prepare a suspension with a mass fraction of 8%. Add 10 kg of aminated graphene and stir at 60 °C for 2 h. Then add 5% of the mass of montmorillonite in cetyltrimethylammonium bromide and continue stirring for 3 h. After filtration and washing, dry under vacuum at 110 °C for 10 h. Grind through a 300-mesh sieve to obtain an aminated graphene / montmorillonite intercalation composite material.

[0032] Preparation Example 5 The aminated graphene / montmorillonite intercalated composite material was prepared by the following method: A1. Add 10 kg of graphene powder to 100 kg of mixed acid, which is concentrated nitric acid and concentrated sulfuric acid in a mass ratio of 1:3.5. Sonicate at 55 °C for 5 h. After washing until neutral, add 2 kg of hydrazine hydrate and reduce at 95 °C for 7 h to obtain reduced graphene oxide. Then add 10 kg of reduced graphene oxide and 2 kg of 3-aminopropyltriethoxysilane to 70 kg of 45% ethanol aqueous solution. Reflux at 75 °C for 9 h. After filtration and drying, obtain aminographene. A2. Disperse 100 kg of montmorillonite in deionized water to prepare a 10% (w / w) suspension. Add 10 kg of aminated graphene and stir at 65 °C for 2.5 h. Then add 6.5% (w / w) of hexadecyltrimethylammonium bromide of montmorillonite and continue stirring for 4 h. After filtration and washing, dry under vacuum at 115 °C for 11 h and grind through a 300-mesh sieve to obtain an aminated graphene / montmorillonite intercalation composite material.

[0033] Preparation Example 6 The aminated graphene / montmorillonite intercalated composite material was prepared by the following method: A1. Add 10 kg of graphene powder to 100 kg of mixed acid, which is concentrated nitric acid and concentrated sulfuric acid in a mass ratio of 1:4. Oxidize at 60 °C for 4 h. After washing until neutral, add 2 kg of hydrazine hydrate and reduce at 100 °C for 8 h to obtain reduced graphene oxide. Then add 10 kg of reduced graphene oxide and 2.5 kg of 3-aminopropyltriethoxysilane to 60 kg of 50% ethanol aqueous solution. Reflux at 80 °C for 10 h. After filtration and drying, obtain aminographene. A2. Disperse 120 kg of montmorillonite in deionized water to prepare a 12% (w / w) suspension. Add 10 kg of aminated graphene and stir at 70 °C for 3 h. Then add 8% (w / w) of hexadecyltrimethylammonium bromide of montmorillonite and continue stirring for 5 h. After filtration and washing, dry under vacuum at 120 °C for 12 h and grind through a 300-mesh sieve to obtain an aminated graphene / montmorillonite intercalation composite material.

[0034] Example Example 1 A waterproof and corrosion-resistant cable material, the raw material composition and dosage of which are shown in Table 1, wherein the modified polyethylene-polyvinyl chloride blend is the modified polyethylene-polyvinyl chloride blend prepared in Preparation Example 1; the aminated graphene / montmorillonite intercalated composite material is the aminated graphene / montmorillonite intercalated composite material prepared in Preparation Example 4; the antioxidant is antioxidant 1010; the lubricant is pentaerythritol stearate; the plasticizer is epoxidized soybean oil; and the compatibilizer is maleic anhydride grafted polyethylene.

[0035] A method for preparing a waterproof and corrosion-resistant cable material includes the following steps: S1. Mix and stir the modified polyethylene-polyvinyl chloride blend, aminated graphene / montmorillonite intercalation composite material, acrylate rubber, carbon nanotubes, nano zinc oxide, antioxidant, lubricant, plasticizer and compatibilizer for 8 minutes to obtain a mixture. S2. Add the mixture to a twin-screw extruder and melt-blend at 160℃ and 90MPa pressure for 2 hours. Then, extrude the mixture through a die and cool and solidify it to obtain a waterproof and corrosion-resistant cable material.

[0036] A waterproof and corrosion-resistant cable comprises, from the inside out: a conductor, an insulation layer, a shielding layer, and a sheath layer. The specifications and materials of each component are as follows: The conductor is made of multi-strand annealed soft copper wire, with a diameter of 0.35mm for each strand and a total of 36 strands. The nominal cross-sectional area of ​​the conductor is 2.2mm². 2 The DC resistance is ≤14.0Ω / km (at 20℃), ensuring that the cable has excellent conductivity and meets the requirements of medium and low voltage power transmission. The insulation layer is extruded from the aforementioned waterproof and corrosion-resistant cable material. The average thickness of the insulation layer is 1.2 mm, with a minimum thickness of 0.8 mm, and it is free of defects such as pinholes and bubbles. This material imparts excellent electrical insulation properties to the insulation layer, with a volume resistivity ≥1×10⁻⁶. 14 Ω·cm (at 20℃), dielectric loss tangent ≤0.005 (at 50Hz). The shielding layer is located outside the insulation layer and is made of tin-plated copper wire with a braiding density of ≥88% and a wire diameter of 0.15mm. The sheath layer is also formed by extruding the waterproof and corrosion-resistant cable prepared in Example 1 above. The average thickness of the sheath layer is 1 mm, the minimum thickness is not less than 0.8 mm, and the surface of the sheath layer is smooth, without cracks or impurities.

[0037] Example 2 A waterproof and corrosion-resistant cable material, the raw material composition and dosage of which are shown in Table 1, wherein the modified polyethylene-polyvinyl chloride blend is selected from the modified polyethylene-polyvinyl chloride blend prepared in Preparation Example 2; the aminated graphene / montmorillonite intercalated composite material is selected from the aminated graphene / montmorillonite intercalated composite material prepared in Preparation Example 5; the antioxidant is antioxidant 1035; the lubricant is pentaerythritol stearate; the plasticizer is epoxidized soybean oil; and the compatibilizer is maleic anhydride grafted polyethylene.

[0038] A method for preparing a waterproof and corrosion-resistant cable material includes the following steps: S1. Mix and stir the modified polyethylene-polyvinyl chloride blend, aminated graphene / montmorillonite intercalation composite material, acrylate rubber, carbon nanotubes, nano zinc oxide, antioxidant, lubricant, plasticizer and compatibilizer for 10 min to obtain a mixture. S2. The mixture is added to a twin-screw extruder and melt-blended at 175°C and 105MPa pressure for 1.5 hours. Then, it is extruded through a die and cooled and solidified to obtain a waterproof and corrosion-resistant cable material.

[0039] Example 3 A waterproof and corrosion-resistant cable material, the raw material composition and dosage of which are shown in Table 1, wherein the modified polyethylene-polyvinyl chloride blend is the modified polyethylene-polyvinyl chloride blend prepared in Preparation Example 3; the aminated graphene / montmorillonite intercalated composite material is the aminated graphene / montmorillonite intercalated composite material prepared in Preparation Example 6; the antioxidant is antioxidant 168; the lubricant is pentaerythritol stearate; the plasticizer is epoxidized soybean oil; and the compatibilizer is maleic anhydride grafted polyethylene.

[0040] A method for preparing a waterproof and corrosion-resistant cable material includes the following steps: S1. Mix and stir the modified polyethylene-polyvinyl chloride blend, aminated graphene / montmorillonite intercalation composite material, acrylate rubber, carbon nanotubes, nano zinc oxide, antioxidant, lubricant, plasticizer and compatibilizer for 12 minutes to obtain a mixture. S2. Add the mixture to a twin-screw extruder and melt-blend at 190°C and 120MPa pressure for 1 hour. Then, extrude the mixture through a die and cool and solidify it to obtain a waterproof and corrosion-resistant cable material.

[0041] Table 1. Raw material composition and dosage (kg) of cable materials in Examples 1-3

[0042] Example 4 A waterproof and corrosion-resistant cable material, which differs from Example 2 in that, in this example, the aminated graphene / montmorillonite intercalated composite material in the cable material is selected from the aminated graphene / montmorillonite intercalated composite material prepared in Preparation Example 4.

[0043] Example 5 A waterproof and corrosion-resistant cable material, which differs from Example 2 in that, in this example, the aminated graphene / montmorillonite intercalated composite material in the cable material is selected from the aminated graphene / montmorillonite intercalated composite material prepared in Preparation Example 6.

[0044] Example 6 A waterproof and corrosion-resistant cable material, which differs from Example 2 in that, in this example, the compatibilizer in the cable material is an ethylene-vinyl acetate copolymer.

[0045] Comparative Example Comparative Example 1 A waterproof and corrosion-resistant cable material, which differs from Example 5 in that an equal amount of polyethylene is used instead of the modified polyethylene-polyvinyl chloride blend in this comparative example, and no aminated graphene / montmorillonite intercalation composite material is added.

[0046] Comparative Example 2 A waterproof and corrosion-resistant cable material, which differs from Example 5 in that an equal amount of unmodified polyethylene-polyvinyl chloride blend is used instead of modified polyethylene-polyvinyl chloride blend in this comparative example.

[0047] Comparative Example 3 A waterproof and corrosion-resistant cable material, which differs from Example 5 in that an equal amount of montmorillonite is used instead of the aminated graphene / montmorillonite intercalation composite material in this comparative example.

[0048] Comparative Example 4 A waterproof and corrosion-resistant cable material, which differs from Example 5 in that no lubricant was added in this comparative example.

[0049] Performance testing The performance of the waterproof and corrosion-resistant cable materials prepared in Examples 1-6 and Comparative Examples 1-4 was tested, and the test results are shown in Table 2.

[0050] 1. Water absorption rate test (refer to GB / T1034-2008 "Determination of water absorption of plastics") (1) Sample pretreatment: Cut the cable material sample prepared above into thin sheets of 50mm×50mm×2mm and dry them in an oven at 105℃ until constant weight (mass recorded as m0, accurate to 0.0001g); (2) Immersion treatment: Immerse the dried sample completely in deionized water at 25℃ and let it stand for 24h; (3) Testing: Take out the sample, quickly absorb the surface moisture with filter paper, and weigh it immediately (recorded as m1, accurate to 0.0001g); (4) Calculation: Water absorption rate = (m1-m0) / m0×100%, each group of samples was tested in parallel 3 times, and the average value was taken. The test results are shown in Table 2.

[0051] 3. Corrosion resistance testing (refer to GB / T11547-2008 "Determination of resistance of plastics to liquid chemical reagents", extending to salt spray conditions) (1) Acid corrosion test: The sample size is 50mm×50mm×2mm. After pretreatment, the mass m2 is weighed; it is immersed in 5% (mass fraction) H2SO4 aqueous solution and soaked at 40℃ for 72h; after taking it out, it is cleaned and dried to constant weight, weighed m3, and the mass change rate is calculated as (m3-m2) / m2×100%. The test results are shown in Table 2.

[0052] (2) Alkali corrosion test: Immerse in 5% (mass fraction) NaOH aqueous solution, and the other conditions are the same as those for acid corrosion test. The test results are shown in Table 2.

[0053] (3) Salt spray corrosion test (refer to GB / T10125-2021 "Artificial Atmosphere Corrosion Test - Salt Spray Test"): The sample size is 50mm×50mm×2mm. It is placed in a salt spray test chamber. The spray medium is 5% NaCl aqueous solution with a pH value of 6.5-7.2, a spray pressure of 0.07-0.1MPa, a test temperature of 35℃, and continuous spraying for 1000h. After the test, the sample is taken out, cleaned, and dried. The surface rust and cracking are observed, and the surface corrosion area ratio is calculated. The test results are shown in Table 2.

[0054] Table 2 Experimental Results

[0055] As shown in Table 2, the water absorption rates of Examples 1-6 are all in the low range of 0.24%-0.34%, with Example 5 having the lowest at only 0.24%. In contrast, Comparative Examples 1 and 2 have water absorption rates as high as 2.98% and 1.65%, respectively, showing a significant difference. This data variation confirms that the cable material in the technical solution of this application has a high level of waterproof performance. Comparative Example 1 uses unmodified polyethylene and a non-intercalated composite material, in which the molecular chain crystal defects and amorphous regions are not filled, allowing for unobstructed water molecule penetration channels. Comparative Example 2 uses an unmodified polyethylene-polyvinyl chloride blend, which lacks the binding of the molecular chains by the cross-linking network, and still has many penetration voids. In this embodiment, dynamic cross-linking modification with zinc dithiocarbamate fills the crystal defects and amorphous free volumes of polyethylene. At the same time, the three-dimensional barrier network constructed by the aminated graphene / montmorillonite intercalation composite material further seals the tiny gaps, forming a synergistic system of "matrix densification + external barrier", which significantly reduces the water molecule penetration ability and thus effectively improves the waterproof performance of the cable material.

[0056] Data on the mass change rate of acid and alkali corrosion showed that the mass change rates of acid and alkali corrosion in the Example series were all below 0.45%, with Example 5 showing rates as low as 0.30% and 0.28%, respectively. In contrast, the mass change rates of Comparative Examples 1-2 all exceeded 1.65%. This difference stems from the synergistic corrosion resistance effect of the modified system: Comparative Examples 1-2, lacking a dynamic cross-linking network, had highly reactive chlorine atoms on the polyvinyl chloride (PVC) molecular chains, making them prone to hydrolysis. Furthermore, without the physical barrier and chemical resistance of the intercalated composite material, corrosive media could quickly penetrate and erode the matrix. The dynamic cross-linking network in the Examples constrained the PVC molecular chains, reduced the activity of chlorine atoms, and alleviated hydrolytic internal stress. The aminated graphene / montmorillonite intercalated composite material, on the other hand, physically blocked the penetration of corrosive media. The excellent chemical stability of graphene synergistically complemented the layered structure of montmorillonite, achieving dual protection of "physical barrier + chemical resistance," thereby significantly reducing the degree of corrosion of the matrix by the corrosive media.

[0057] The data on the percentage of corrosion area on the surface during salt spray corrosion further highlight the crucial role of the intercalated composite material. The percentage of corrosion area in the Example series was less than 0.92%, with Example 5 at only 0.65%. In contrast, Comparative Example 3 (using montmorillonite instead of the intercalated composite material) and Comparative Example 4 (without lubricant) had percentages of 12.8% and 13.5%, respectively, while Comparative Example 1 reached a staggering 46.2%. Comparative Example 3, using only montmorillonite, lacked the intercalation and dispersion effect of aminated graphene, leading to easy aggregation of the montmorillonite sheets and the inability to form a continuous barrier network. Corrosive media could penetrate through the gaps between these aggregates. Comparative Example 4, lacking lubricant, resulted in uneven mixing of raw materials, unbalanced component dispersion, and defects in the protective system. The aminated graphene / montmorillonite intercalated composite material used in the Examples, through aminated modification, achieves uniform dispersion of graphene between montmorillonite sheets, constructing a continuous three-dimensional barrier network. This effectively delays the diffusion of salt spray media. Simultaneously, the amino groups form hydrogen bonds with the polar groups of the matrix, improving compatibility, avoiding aggregation defects, and significantly enhancing corrosion resistance in salt spray environments.

[0058] The data differences within the examples also confirm the optimization effect of raw material ratios and preparation process parameters. All corrosion protection indicators of Examples 2-5 are superior to those of Examples 1 and 6, with Example 5 showing the best performance. Examples 2-5 used modified polyethylene-polyvinyl chloride blends and aminated graphene / montmorillonite intercalated composite materials with optimized ratios. Appropriate mixing times and melt blending parameters were controlled during the preparation process to ensure uniform dispersion of each component, allowing the dynamic crosslinking network and intercalated barrier network to be tightly bonded, maximizing the synergistic effect. In Example 1, due to the lower limit of raw material usage, the synergistic protective effect of the modified matrix and intercalated composite material was slightly weaker. In Example 6, due to the change in the type of compatibilizer, the compatibility between the aminated graphene / montmorillonite and the matrix decreased slightly, resulting in a slight decline in protective performance. This also illustrates that the choice of compatibilizer has a significant impact on the overall protective performance of the material.

[0059] In summary, the performance indicators of the example series are significantly better than those of the comparative examples, fully demonstrating the effectiveness of the technical solution of this application. The synergistic effect of the dynamically cross-linked modified polyethylene-polyvinyl chloride blend and the aminated graphene / montmorillonite intercalated composite material is the core of improving the waterproof and corrosion-resistant performance of the material. The preparation process, including staged temperature-controlled mixing, gradient mixing, and precise melt blending, ensures the uniform dispersion of each component and the complete construction of the protective system, effectively solving the pain point of the difficulty in achieving both waterproof and corrosion-resistant performance in the prior art. Example 5 maximizes the synergistic protective effect by optimizing the raw material ratio and preparation parameters, exhibiting the best comprehensive waterproof and corrosion-resistant performance.

[0060] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A water resistant, corrosion resistant cable material, characterized by, The raw materials include the following components by weight: modified polyethylene-polyvinyl chloride blend 55-75 parts; amino-functionalized graphene / montmorillonite intercalation composite 5-10 parts; acrylate rubber 5-15 parts; carbon nanotube 1-3 parts; nano zinc oxide 2-4 parts; antioxidant 1-2 parts; lubricant 0.5-1.5 parts; plasticizer 3-6 parts; compatibilizer 2-5 parts; The modified polyethylene-polyvinyl chloride blend is obtained by cross-linking modification of polyethylene-polyvinyl chloride blend with zinc dithiocarbamate.

2. A water resistant corrosion resistant cable material as claimed in claim 1, wherein, The modified polyethylene-polyvinyl chloride blend is prepared by the following method: The high-density polyethylene and polyvinyl chloride are added into a banbury mixer, and mixed for 10-15 min at 160-170℃, then zinc dithiocarbamate is added, and mixed for 8-12 min, then triallyl isocyanurate is added, and mixed for 5-8 min at 170-180℃, and the mixture is discharged, cooled, and crushed to pass through a 100 mesh sieve to obtain the modified polyethylene-polyvinyl chloride blend.

3. A water resistant, corrosion resistant cable material according to claim 2, characterized in that: The high-density polyethylene has a molecular weight of 150-300 thousand; the mass ratio of the high-density polyethylene to polyvinyl chloride is 1: (1.5-2).

4. A water resistant corrosion resistant cable material as claimed in claim 2, wherein: The amount of zinc dithiocarbamate added is 3%-6% of the total mass of the high-density polyethylene and polyvinyl chloride; the amount of triallyl isocyanurate added is 1%-3% of the total mass of the high-density polyethylene and polyvinyl chloride.

5. A water resistant corrosion resistant cable material as defined in claim 1, wherein, The amino-functionalized graphene / montmorillonite intercalation composite is prepared by the following method: A1, graphene powder is added into mixed acid, and ultrasonic oxidation is performed for 4-6 h at 50-60℃, then the product is washed to neutral, hydrazine hydrate is added, and reduction is performed for 6-8 h at 90-100℃ to obtain reduced graphene oxide; then the reduced graphene oxide and 3-aminopropyl triethoxysilane are added into an aqueous ethanol solution, and reflux reaction is performed for 8-10 h at 70-80℃, and the product is filtered and dried to obtain amino-functionalized graphene; A2, montmorillonite is dispersed in deionized water to prepare a suspension with a mass fraction of 8-12%, then amino-functionalized graphene is added, and stirring and dispersion are performed for 2-3 h at 60-70℃, then cetyltrimethylammonium bromide is added in an amount of 5-8% of the mass of the montmorillonite, and stirring and reaction are continued for 3-5 h, then the product is filtered, washed, and vacuum dried for 10-12 h at 110-120℃, and the product is ground to pass through a 300 mesh sieve to obtain the amino-functionalized graphene / montmorillonite intercalation composite.

6. A water resistant, corrosion resistant cable material as defined in claim 5, wherein: In step A1, the mixed acid is concentrated nitric acid and concentrated sulfuric acid in a mass ratio of 1: (3-4); the amount of 3-aminopropyl triethoxysilane added is 15%-25% of the mass of the reduced graphene oxide.

7. A water resistant, corrosion resistant cable material as defined in claim 5, wherein: In step A2, the mass ratio of amino-functionalized graphene to montmorillonite is 1: (8-12).

8. A water resistant, corrosion resistant cable material as defined in claim 1, wherein: The antioxidant is at least one of antioxidant 1010, antioxidant 1035, and antioxidant 168.

9. A process for the preparation of a water resistant corrosion resistant cable material according to any one of claims 1 to 8, characterized in that, The method comprises the following steps: S1, the modified polyethylene-polyvinyl chloride blend, amino-functionalized graphene / montmorillonite intercalation composite, acrylate rubber, carbon nanotube, nano zinc oxide, antioxidant, lubricant, plasticizer, and compatibilizer are mixed and stirred for 8-12 min to obtain a mixture; S2, the mixture is added into a twin-screw extruder, melt-blended at 160-190℃ under 90-120MPa pressure for 1-2h, then extruded into a mold, and after cooling and solidification, a waterproof and corrosion-resistant cable material is obtained.

10. A water resistant, corrosion resistant cable, characterized by, The waterproof and corrosion-resistant cable material according to any one of claims 1-8 is used as a sheath layer and / or an insulation layer.

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