High strength environmentally resistant aerial cable

Abstract

This invention relates to the field of cables and proposes a high-strength, environmentally corrosion-resistant overhead cable. From the inside out, it comprises a conductor, a shielding layer, and an insulation layer. The insulation layer comprises the following raw materials in parts by weight: 80-100 parts linear high-density polyethylene, 10-15 parts corrosion-resistant filler, 15-17 parts fluororesin, 1-2 parts antioxidant, 10-12 parts flame retardant, and 1-1.5 parts lubricant. The corrosion-resistant filler comprises the following raw materials in parts by weight: 100 parts sericite, 8-12 parts composite silicon source precursor, and 4-6 parts tetrabutyl titanate. The composite silicon source precursor includes tetraethyl orthosilicate and polyethylene glycol monomethyl ether. This technical solution solves the problems of low insulation strength and poor corrosion resistance in related technologies for overhead cables.

Description

Technical Field

[0001] This invention relates to the field of cable technology, and more specifically, to a high-strength, environmentally resistant overhead cable. Background Technology

[0002] Overhead cables are core transmission components of outdoor medium- and low-voltage power distribution networks. Exposed to the natural environment for extended periods, they are susceptible to corrosion from salt spray, chemical gases, ultraviolet radiation, and fluctuating temperature and humidity. Therefore, they require high corrosion resistance. Existing overhead cables often use ordinary cross-linked polyethylene and polyethylene insulation materials, which lack sufficient strength and corrosion resistance. Long-term use can lead to insulation swelling, cracking, embrittlement, and degradation, resulting in conductor electrochemical corrosion within the cable. This can cause insulation breakdown, leakage, line interruption, and even short circuits and fires, significantly shortening cable lifespan and increasing grid maintenance risks. Therefore, a high-strength, environmentally resistant overhead cable is needed. Summary of the Invention

[0003] This invention proposes a high-strength, environmentally resistant overhead cable to solve or alleviate at least one of the aforementioned problems.

[0004] The technical solution of the present invention is as follows: A high-strength, environmentally resistant overhead cable comprises, from the inside out, a conductor, a shielding layer, and an insulation layer. The insulation layer comprises the following raw materials in parts by weight: 80-100 parts of linear high-density polyethylene, 10-15 parts of corrosion-resistant filler, 15-17 parts of fluororesin, 1-2 parts of antioxidant, 10-12 parts of flame retardant, and 1-1.5 parts of lubricant. The corrosion-resistant filler comprises the following raw materials in parts by weight: 100 parts sericite, 8-12 parts composite silicon source precursor, and 4-6 parts tetrabutyl titanate; the composite silicon source precursor comprises tetraethyl orthosilicate and polyethylene glycol monomethyl ether.

[0005] As a further technical solution, the mass ratio of tetraethyl orthosilicate to polyethylene glycol monomethyl ether is 5~9:1, preferably 7:1.

[0006] As a further technical solution, the number average molecular weight of the polyethylene glycol monomethyl ether is 350-500, preferably 400.

[0007] As a further technical solution, the method for preparing the corrosion-resistant filler includes the following steps: A1. The sericite is dispersed in a solvent, a composite silicon source precursor is added, the pH is adjusted to 8-9 and then mixed, followed by filtration, washing and drying to obtain the filler intermediate. A2. Disperse the intermediate filler in water, adjust the pH to 2-3, add an ethanol solution of tetrabutyl titanate and mix, then filter, wash and dry to obtain the corrosion-resistant filler.

[0008] As a further technical solution, in step A1, the mixing temperature is 40~50℃ and the mixing time is 4~6h.

[0009] As a further technical solution, in step A2, the mixing temperature is 80~120℃ and the mixing time is 16~18h.

[0010] As a further technical solution, the fluororesin includes a copolymer of polyvinylidene fluoride and ethylene-tetrafluoroethylene in a mass ratio of 2 to 4:1.

[0011] Preferably, the fluororesin comprises a copolymer of polyvinylidene fluoride and ethylene-tetrafluoroethylene in a mass ratio of 3:1.

[0012] As a further technical solution, the melt flow rate of the polyvinylidene fluoride is 5~11 g / 10 min, preferably 8 g / 10 min, and the test conditions are 230℃ / 2.16 kg; the melt flow rate of the ethylene-tetrafluoroethylene copolymer is 7~18 g / 10 min, preferably 9 g / 10 min, and the test conditions are 297℃ / 5.0 kg.

[0013] As a further technical solution, the flame retardant includes one or more of halogenated flame retardants, halogen-free flame retardants, phosphorus-based flame retardants, nitrogen-based flame retardants, and inorganic flame retardants.

[0014] As a further technical solution, the lubricant includes one or more of the following: fatty acid lubricants, fatty acid ester lubricants, fatty amide lubricants, paraffin lubricants, and metal soap lubricants.

[0015] The beneficial effects of this invention are as follows: This invention incorporates a corrosion-resistant filler, prepared from sericite, tetrabutyl titanate, tetraethyl orthosilicate, and polyethylene glycol monomethyl ether, into the insulation layer of a high-strength, environmentally resistant overhead cable. This filler enhances the corrosion resistance of the insulation layer. By using a composite silicon precursor composed of tetraethyl orthosilicate and polyethylene glycol monomethyl ether, combined with tetrabutyl titanate, a composite oxide coating layer is formed in situ on the surface of sericite. This surface modification of sericite improves its dispersion within the insulation matrix, thereby enhancing the overall corrosion resistance of the filler and improving the strength and corrosion resistance of the overhead cable insulation layer. Detailed Implementation

[0016] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0017] To improve corrosion resistance and mechanical strength, existing overhead cables often add inorganic fillers such as sericite to the insulation matrix. However, sericite has strong surface polarity and high surface energy, resulting in poor compatibility with organic insulation matrix and easy agglomeration. This leads to uneven dispersion of sericite in the insulation layer, making it difficult to fully utilize its chemical corrosion resistance. It also easily forms defects and stress concentration points, reducing the density and integrity of the insulation layer, resulting in poor corrosion resistance and making it difficult to meet the requirements for long-term use in harsh environments.

[0018] To address the aforementioned problems, this invention employs a method using sericite, tetrabutyl titanate, tetraethyl orthosilicate, and polyethylene glycol monomethyl ether as raw materials to prepare a corrosion-resistant filler. Tetraethyl orthosilicate and polyethylene glycol monomethyl ether form a composite silicon source precursor, which, in conjunction with tetrabutyl titanate, generates a composite oxide coating layer in situ on the surface of sericite. This surface modification of sericite improves its surface polarity, enhances its compatibility with the matrix, and increases its dispersibility. Simultaneously, the highly stable composite oxide enhances the overall chemical resistance of the filler, thereby significantly improving the corrosion resistance of the insulation layer and increasing the cable's service life and operational reliability.

[0019] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will be described through embodiments.

[0020] A specific embodiment of the first aspect of the present invention provides a high-strength, environmentally resistant overhead cable, which includes, from the inside out, a conductor, a shielding layer, and an insulation layer. The insulation layer comprises the following raw materials in parts by weight: 80-100 parts of linear high-density polyethylene, 10-15 parts of corrosion-resistant filler, 15-17 parts of fluororesin, 1-2 parts of antioxidant, 10-12 parts of flame retardant, and 1-1.5 parts of lubricant. The corrosion-resistant filler comprises the following raw materials in parts by weight: 100 parts sericite, 8-12 parts composite silicon source precursor, and 4-6 parts tetrabutyl titanate; the composite silicon source precursor includes tetraethyl orthosilicate and polyethylene glycol monomethyl ether.

[0021] In this invention, the mass ratio of tetraethyl orthosilicate to polyethylene glycol monomethyl ether is 5 to 9:1, for example, it can be any value among 5:1, 6:1, 7:1, 8:1, and 9:1, or any range between any two values, preferably 7:1.

[0022] In this invention, the number average molecular weight of polyethylene glycol monomethyl ether is 350 to 500, for example, it can be any point value among 350, 400, and 500 and the range between any two point values, preferably 400.

[0023] In this invention, the method for preparing corrosion-resistant filler includes the following steps: A1. Disperse sericite in a solvent, add the composite silicon source precursor, adjust the pH to 8-9 and mix, then filter, wash and dry to obtain the filler intermediate; A2. Disperse the intermediate filler in water, adjust the pH to 2-3, add an ethanol solution of tetrabutyl titanate and mix, then filter, wash and dry to obtain corrosion-resistant filler.

[0024] In step A1 of this invention, the mixing temperature is 40~50℃, for example, it can be any point value among 40℃, 42℃, 45℃, 48℃, and 50℃ and the range between any two point values; the mixing time is 4~6h, for example, it can be any point value among 4h, 4.5h, 5h, 5.5h, and 6h and the range between any two point values.

[0025] In step A1 of this invention, the solvent is an aqueous ethanol solution of 60wt% to 75wt%, for example, it can be any point value or any range between any two point values ​​from 60wt%, 62wt%, 65wt%, 68wt%, 70wt%, 72wt%, 75wt%; the mass-volume ratio of sericite to solvent is 1g:8~12mL, for example, it can be any point value or any range between any two point values ​​from 1g:8mL, 1g:9mL, 1g:10mL, 1g:11mL, 1g:12mL.

[0026] In step A2 of the present invention, the mass fraction of tetrabutyl titanate in the ethanol solution is 8wt% to 15wt%, for example, it can be any point value among 8wt%, 10wt%, 11wt%, 12wt%, 14wt%, and 15wt%, or any range between any two point values.

[0027] In step A2 of this invention, the mixing temperature is 80~120℃, for example, it can be any point value among 80℃, 90℃, 100℃, 110℃, and 120℃ and the range between any two point values; the mixing time is 16~18h, for example, it can be any point value among 16h, 16.5h, 17h, 17.5h, and 18h ​​and the range between any two point values.

[0028] In this invention, the fluororesin includes a copolymer of polyvinylidene fluoride and ethylene-tetrafluoroethylene in a mass ratio of 2 to 4:1. For example, it can be any point value from 2:1, 2.5:1, 3:1, 3.5:1, 4:1 and any range between any two point values, preferably 3:1.

[0029] In this invention, the melt flow rate of polyvinylidene fluoride is 5~11 g / 10 min, for example, it can be any point value or any range between two points from 5 g / 10 min, 8 g / 10 min, and 11 g / 10 min, preferably 8 g / 10 min, and the test conditions are 230℃ / 2.16 kg; the melt flow rate of ethylene-tetrafluoroethylene copolymer is 7~18 g / 10 min, for example, it can be any point value or any range between two points from 7 g / 10 min, 9 g / 10 min, and 18 g / 10 min, preferably 9 g / 10 min, and the test conditions are 297℃ / 5.0 kg.

[0030] In this invention, the flame retardant includes one or more of halogenated flame retardants, halogen-free flame retardants, phosphorus-based flame retardants, nitrogen-based flame retardants, and inorganic flame retardants. Halogenated flame retardants may be, for example, at least one of polybrominated diphenyl ethers, tetrabromobisphenol A, hexabromocyclododecane, and decabromodiphenyl ethane; halogen-free flame retardants may be, for example, at least one of aluminum hydroxide, magnesium hydroxide, zinc borate, and hydrated alumina; phosphorus-based flame retardants may be, for example, at least one of phosphate esters, ammonium polyphosphate, diammonium hydrogen phosphate, and ammonium dihydrogen phosphate; nitrogen-based flame retardants may be, for example, at least one of melamine, melamine cyanurate, melamine phosphate, and urea-formaldehyde resin; and inorganic flame retardants may be, for example, at least one of antimony trioxide, tin dioxide, zinc oxide, and magnesium oxide.

[0031] In this invention, the antioxidant includes one or more of phenolic antioxidants, amine antioxidants, phosphite antioxidants, thioester antioxidants, and compound antioxidants. Phenolic antioxidants, such as at least one of antioxidant BHT, antioxidant 2246, antioxidant 1010, and antioxidant 1135; amine antioxidants, such as at least one of N-phenyl-α-naphthylamine, N,N'-diphenyl-p-phenylenediamine, N-isopropyl-N'-phenyl-p-phenylenediamine, and antioxidant 4010NA; phosphite antioxidants, such as at least one of triphenyl phosphite, antioxidant 168, diphenyl octyl phosphite, and trioctyl phosphite; thioester antioxidants, such as at least one of antioxidant DLTP, antioxidant DSTP, ditetradecyl thiodipropionate, and dilauryl thiodipropionate; and compound antioxidants, such as at least one of antioxidant 1010 and antioxidant 168, antioxidant 2246 and triphenyl phosphite, and antioxidant 1135 and antioxidant DLTP.

[0032] In this invention, the lubricant includes one or more of the following: fatty acid lubricants, fatty acid ester lubricants, fatty amide lubricants, paraffin lubricants, and metal soap lubricants. Fatty acid lubricants may be, for example, at least one of stearic acid, palmitic acid, lauric acid, and oleic acid; fatty acid ester lubricants may be, for example, at least one of butyl stearate, isooctyl stearate, methyl palmitate, and ethyl oleate; fatty amide lubricants may be, for example, at least one of stearamide, oleamide, erucamide, and linoleamide; paraffin lubricants may be, for example, at least one of liquid paraffin, microcrystalline wax, polyethylene wax, and oxidized polyethylene wax; and metal soap lubricants may be, for example, at least one of calcium stearate, zinc stearate, magnesium stearate, and barium stearate.

[0033] A specific embodiment of the second aspect of the present invention provides a method for preparing a high-strength environmentally resistant overhead cable, which is used to prepare the high-strength environmentally resistant overhead cable provided in the specific embodiment of the first aspect of the present invention.

[0034] In one embodiment of the present invention, a method for preparing a high-strength environmentally resistant overhead cable includes the following steps: covering the outside of the conductor with a shielding layer material to form a shielding layer; then mixing the insulating layer raw materials evenly and extruding them onto the outside of the shielding layer to form an insulating layer, thereby obtaining a high-strength environmentally resistant overhead cable.

[0035] In this invention, the conductor can be either an aluminum alloy conductor or a copper conductor; the shielding layer material can be either galvanized braided copper wire or tin-plated braided copper wire.

[0036] The present invention will now be described in detail with reference to preferred embodiments and comparative examples. The preferred embodiments of the invention described below can be modified in various ways, and therefore the scope of the invention should not be construed as limited to the preferred embodiments described in detail below. Preferred embodiments are provided to help those skilled in the art to more readily understand the invention.

[0037] In the following examples and comparative examples, linear high-density polyethylene, model DMDA-8920; aluminum hydroxide, particle size 1 μm; magnesium hydroxide, particle size 1 μm; zinc borate, particle size 2 μm; sericite, particle size 5 μm.

[0038] Example 1 A high-strength, environmentally resistant overhead cable comprises, from the inside out, a conductor, a shielding layer, and an insulation layer. The insulation layer comprises the following raw materials in parts by weight: 80 parts linear high-density polyethylene, 10 parts corrosion-resistant filler, 15 parts fluororesin, 1 part antioxidant 2246, 10 parts zinc borate, and 1 part stearic acid. The fluororesin comprises polyvinylidene fluoride (melt flow rate 8 g / 10 min, test conditions 230℃ / 2.16 kg, model KF 1300) and ethylene-tetrafluoroethylene copolymer (melt flow rate 9 g / 10 min, test conditions 297℃ / 5.0 kg, model 6210AZ) in a mass ratio of 2:1. The preparation method of corrosion-resistant filler includes the following steps: A1. Disperse 100 parts of sericite in a 70wt% ethanol aqueous solution, add 8 parts of composite silicon source precursor, adjust the pH to 8, mix at 40℃ for 6 hours, then filter, wash and dry to obtain the filler intermediate; the composite silicon source precursor is composed of tetraethyl orthosilicate and polyethylene glycol monomethyl ether (molecular weight 400) in a mass ratio of 5:1; the mass-volume ratio of sericite to solvent is 1g:10mL; A2. The intermediate filler was dispersed in water, and the pH was adjusted to 2. Then, an ethanol solution of tetrabutyl titanate was added. After mixing at 80°C for 18 hours, the mixture was filtered, washed, and dried to obtain the corrosion-resistant filler. The ethanol solution of tetrabutyl titanate contained 4 parts of tetrabutyl titanate, and the mass fraction of tetrabutyl titanate was 12 wt%. A method for preparing a high-strength, environmentally resistant overhead cable includes the following steps: wrapping galvanized braided copper wire around the outside of a copper conductor to form a shielding layer; then mixing the insulation material evenly and extruding it around the outside of the shielding layer to form an insulation layer, thereby obtaining a high-strength, environmentally resistant overhead cable.

[0039] Example 2 A high-strength, environmentally resistant overhead cable comprises, from the inside out, a conductor, a shielding layer, and an insulation layer. The insulation layer comprises the following raw materials in parts by weight: 90 parts linear high-density polyethylene, 12 parts corrosion-resistant filler, 16 parts fluororesin, 1.5 parts antioxidant 1135, 11 parts aluminum hydroxide, and 1.2 parts oleic acid. The fluororesin comprises polyvinylidene fluoride (melt flow rate 8 g / 10 min, test conditions 230℃ / 2.16 kg, model KF 1300) and ethylene-tetrafluoroethylene copolymer (melt flow rate 9 g / 10 min, test conditions 297℃ / 5.0 kg, model 6210AZ) in a mass ratio of 2:1. The preparation method of corrosion-resistant filler includes the following steps: A1. Disperse 100 parts of sericite in a 70wt% ethanol aqueous solution, add 10 parts of composite silicon source precursor, adjust the pH to 8.5, mix at 45℃ for 5h, then filter, wash and dry to obtain the filler intermediate; the composite silicon source precursor is composed of tetraethyl orthosilicate and polyethylene glycol monomethyl ether (molecular weight 350) in a mass ratio of 5:1; the mass-volume ratio of sericite to solvent is 1g:10mL; A2. The intermediate filler was dispersed in water, and the pH was adjusted to 3. Then, an ethanol solution of tetrabutyl titanate was added. After mixing at 100°C for 17 hours, the mixture was filtered, washed, and dried to obtain the corrosion-resistant filler. The ethanol solution of tetrabutyl titanate contained 5 parts of tetrabutyl titanate, and the mass fraction of tetrabutyl titanate was 12 wt%. A method for preparing a high-strength, environmentally resistant overhead cable includes the following steps: wrapping galvanized braided copper wire around the outside of a copper conductor to form a shielding layer; then mixing the insulation material evenly and extruding it around the outside of the shielding layer to form an insulation layer, thereby obtaining a high-strength, environmentally resistant overhead cable.

[0040] Example 3 A high-strength, environmentally resistant overhead cable comprises, from the inside out, a conductor, a shielding layer, and an insulation layer. The insulation layer comprises the following raw materials in parts by weight: 100 parts linear high-density polyethylene, 15 parts corrosion-resistant filler, 17 parts fluororesin, 2 parts antioxidant 168, 12 parts magnesium hydroxide, and 1.5 parts stearamide. The fluororesin comprises polyvinylidene fluoride (melt flow rate 8 g / 10 min, test conditions 230℃ / 2.16 kg, model KF 1300) and ethylene-tetrafluoroethylene copolymer (melt flow rate 9 g / 10 min, test conditions 297℃ / 5.0 kg, model 6210AZ) in a mass ratio of 2:1. The preparation method of corrosion-resistant filler includes the following steps: A1. Disperse 100 parts of sericite in a 70wt% ethanol aqueous solution, add 12 parts of composite silicon source precursor, adjust the pH to 9, mix at 50℃ for 4 hours, then filter, wash and dry to obtain the filler intermediate; the composite silicon source precursor is composed of tetraethyl orthosilicate and polyethylene glycol monomethyl ether (molecular weight 500) in a mass ratio of 5:1; the mass-volume ratio of sericite to solvent is 1g:10mL; A2. The intermediate filler was dispersed in water, and the pH was adjusted to 3. Then, an ethanol solution of tetrabutyl titanate was added. After mixing at 120°C for 16 hours, the mixture was filtered, washed, and dried to obtain the corrosion-resistant filler. The ethanol solution of tetrabutyl titanate contained 6 parts of tetrabutyl titanate, and the mass fraction of tetrabutyl titanate was 12 wt%. A method for preparing a high-strength, environmentally resistant overhead cable includes the following steps: wrapping galvanized braided copper wire around the outside of a copper conductor to form a shielding layer; then mixing the insulation material evenly and extruding it around the outside of the shielding layer to form an insulation layer, thereby obtaining a high-strength, environmentally resistant overhead cable.

[0041] Example 4 Except for replacing the composite silicon source precursor with tetraethyl orthosilicate and polyethylene glycol monomethyl ether (molecular weight 400) in a mass ratio of 7:1, everything else is the same as in Example 1.

[0042] Example 5 Except for replacing the composite silicon source precursor with tetraethyl orthosilicate and polyethylene glycol monomethyl ether (molecular weight 400) in a mass ratio of 9:1, the rest is the same as in Example 1.

[0043] Example 6 Except for replacing the fluoropolymer with polyvinylidene fluoride (melt flow rate of 8 g / 10 min, test conditions of 230 °C / 2.16 kg, model KF 1300) and ethylene-tetrafluoroethylene copolymer (melt flow rate of 9 g / 10 min, test conditions of 297 °C / 5.0 kg, model 6210AZ) at a mass ratio of 3:1, everything else is the same as in Example 1.

[0044] Example 7 Except for replacing the fluoropolymer with polyvinylidene fluoride (melt flow rate of 8 g / 10 min, test conditions of 230 °C / 2.16 kg, model KF 1300) and ethylene-tetrafluoroethylene copolymer (melt flow rate of 9 g / 10 min, test conditions of 297 °C / 5.0 kg, model 6210AZ) at a mass ratio of 4:1, everything else is the same as in Example 1.

[0045] Example 8 Except for replacing the fluoropolymer with polyvinylidene fluoride (melt flow rate of 5 g / 10 min, test conditions of 230 °C / 2.16 kg, model PVDF 11008 / 0001) and ethylene-tetrafluoroethylene copolymer (melt flow rate of 9 g / 10 min, test conditions of 297 °C / 5.0 kg, model 6210AZ) at a mass ratio of 2:1, everything else is the same as in Example 1.

[0046] Example 9 Except for replacing the fluoropolymer with polyvinylidene fluoride (melt flow rate 11 g / 10 min, test conditions 230 °C / 2.16 kg, model PVDF 31508 / 0003) and ethylene-tetrafluoroethylene copolymer (melt flow rate 9 g / 10 min, test conditions 297 °C / 5.0 kg, model 6210AZ) at a mass ratio of 2:1, everything else is the same as in Example 1.

[0047] Example 10 Except for replacing the fluoropolymer with polyvinylidene fluoride (melt flow rate of 8 g / 10 min, test conditions of 230 °C / 2.16 kg, model KF 1300) and ethylene-tetrafluoroethylene copolymer (melt flow rate of 7 g / 10 min, test conditions of 297 °C / 5.0 kg, model Tefzel 750) at a mass ratio of 2:1, everything else is the same as in Example 1.

[0048] Example 11 Except for replacing the fluoropolymer with polyvinylidene fluoride (melt flow rate of 8 g / 10 min, test conditions of 230 °C / 2.16 kg, model KF 1300) and ethylene-tetrafluoroethylene copolymer (melt flow rate of 18 g / 10 min, test conditions of 297 °C / 5.0 kg, model 6218Z) at a mass ratio of 2:1, everything else is the same as in Example 1.

[0049] Comparative Example 1 Except for replacing the preparation method of the corrosion-resistant filler with the following preparation method, the rest is the same as in Embodiment 1; The preparation method of corrosion-resistant filler includes the following steps: A1. Disperse 100 parts of sericite in a 70wt% ethanol aqueous solution, add 8 parts of tetraethyl orthosilicate, adjust the pH to 8, mix at 40℃ for 6 hours, then filter, wash and dry to obtain the filler intermediate; the mass-volume ratio of sericite to solvent is 1g:10mL. A2. Disperse the intermediate filler in water, adjust the pH to 2, add an ethanol solution of tetrabutyl titanate, mix at 80℃ for 18 hours, filter, wash and dry to obtain corrosion-resistant filler; the ethanol solution of tetrabutyl titanate contains 4 parts of tetrabutyl titanate, and the mass fraction of tetrabutyl titanate is 12wt%.

[0050] Comparative Example 2 Except for replacing the corrosion-resistant filler with an equal amount of sericite, the rest is the same as in Implementation 1.

[0051] The insulation layers of the high-strength, environmentally resistant overhead cables of Examples 1-5 and Comparative Examples 1-2 were subjected to the following performance tests: Corrosion resistance test: The insulation layer of the high-strength environmentally resistant overhead cable was immersed in a 55 g / L oxalic acid aqueous solution. Simultaneously, the tensile strength of the insulation layer before immersion and the tensile strength after immersion at 23±2℃ for 5 days were determined according to the test methods in GB / T2951.11-2008 "General Test Methods for Insulation and Sheath Materials of Cables and Optical Fibers". The test specimen was a dumbbell-shaped specimen with a thickness of 1.5 mm, and the clamp moving speed was 20 mm / min. The test results are shown in Table 1. Table 1. Test results of corrosion resistance of insulation layer of high-strength environmentally resistant overhead cable

[0052] As shown in Table 1, the comparison between Examples 1-5 and Comparative Examples 1-2 demonstrates that the addition of the corrosion-resistant filler prepared by the present invention can improve the corrosion resistance and strength of overhead cables.

[0053] The insulation layers of the high-strength, environmentally resistant overhead cables of Examples 1, 6-11 were subjected to the following performance tests: Tensile strength test: The tensile strength of the insulation layer of high-strength environmentally resistant overhead cables was determined according to the test method in GB / T2951.11-2008 "General Test Methods for Insulation and Sheath Materials of Cables and Optical Fibers". The test specimen was a dumbbell-shaped specimen with a thickness of 1.5 mm, and the clamp moving speed was 20 mm / min. The test results are shown in Table 2. Table 2. Test results of tensile strength of insulation layer of high-strength environmentally resistant overhead cables

[0054] As shown in Table 2, the comparison of Examples 1, 6-11 indicates that when the fluororesin includes polyvinylidene fluoride and ethylene-tetrafluoroethylene copolymer in a mass ratio of 2-4:1, and the melt flow rate of polyvinylidene fluoride is 5-11 g / 10 min, and the test conditions are 230℃ / 2.16 kg; and the melt flow rate of ethylene-tetrafluoroethylene copolymer is 7-18 g / 10 min, and the test conditions are 297℃ / 5.0 kg, the tensile strength of the insulation layer of the overhead cable can be improved.

[0055] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-strength, environmentally resistant overhead cable, characterized in that, From the inside out, it includes a conductor, a shielding layer, and an insulating layer. The insulating layer comprises the following raw materials in parts by weight: 80-100 parts of linear high-density polyethylene, 10-15 parts of corrosion-resistant filler, 15-17 parts of fluororesin, 1-2 parts of antioxidant, 10-12 parts of flame retardant, and 1-1.5 parts of lubricant. The corrosion-resistant filler comprises the following raw materials in parts by weight: 100 parts sericite, 8-12 parts composite silicon source precursor, and 4-6 parts tetrabutyl titanate; the composite silicon source precursor comprises tetraethyl orthosilicate and polyethylene glycol monomethyl ether.

2. The high-strength, environmentally resistant overhead cable according to claim 1, characterized in that, The mass ratio of tetraethyl orthosilicate to polyethylene glycol monomethyl ether is 5~9:

1.

3. The high-strength, environmentally resistant overhead cable according to claim 2, characterized in that, The number-average molecular weight of the polyethylene glycol monomethyl ether is 350-500.

4. A high-strength, environmentally resistant overhead cable according to claim 1, characterized in that, The method for preparing the corrosion-resistant filler includes the following steps: A1. The sericite is dispersed in a solvent, a composite silicon source precursor is added, the pH is adjusted to 8-9 and then mixed, followed by filtration, washing and drying to obtain the filler intermediate. A2. Disperse the intermediate filler in water, adjust the pH to 2-3, add an ethanol solution of tetrabutyl titanate and mix, then filter, wash and dry to obtain the corrosion-resistant filler.

5. A high-strength, environmentally resistant overhead cable according to claim 4, characterized in that, In step A1, the mixing temperature is 40~50℃ and the mixing time is 4~6h.

6. A high-strength, environmentally resistant overhead cable according to claim 4, characterized in that, In step A2, the mixing temperature is 80~120℃ and the mixing time is 16~18h.

7. A high-strength, environmentally resistant overhead cable according to claim 1, characterized in that, The fluororesin comprises a copolymer of polyvinylidene fluoride and ethylene-tetrafluoroethylene in a mass ratio of 2 to 4:

1.

8. A high-strength, environmentally resistant overhead cable according to claim 7, characterized in that, The melt flow rate of the polyvinylidene fluoride is 5~11 g / 10 min, and the test conditions are 230℃ / 2.16 kg; the melt flow rate of the ethylene-tetrafluoroethylene copolymer is 7~18 g / 10 min, and the test conditions are 297℃ / 5.0 kg.

9. A high-strength, environmentally resistant overhead cable according to claim 1, characterized in that, The flame retardant includes one or more of the following: halogenated flame retardants, halogen-free flame retardants, phosphorus-based flame retardants, nitrogen-based flame retardants, and inorganic flame retardants.

10. A high-strength, environmentally resistant overhead cable according to claim 1, characterized in that, The lubricant includes one or more of the following: fatty acid lubricants, fatty acid ester lubricants, fatty amide lubricants, paraffin lubricants, and metal soap lubricants.

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