Anti-crack insulated cable

Abstract

The invention discloses an anti-crack insulated cable, and belongs to the technical field of cables. Comprising a conductor, an insulating layer, a shielding layer and an outer sheath, wherein the outer sheath is prepared from the following raw materials in parts by weight: 88-100 parts of Levapren rubber, 7-17 parts of an anti-corrosion reinforcing agent, 5-10 parts of an organic flame retardant, 6-9 parts of an inorganic flame retardant, 3-4 parts of a processing aid, 2-3 parts of a vulcanizing agent and 0.4-0.8 part of a vulcanization accelerator. Wherein the molecules of the anti-corrosion reinforcing agent contain a plurality of functional groups, so that the mechanical strength and the anti-corrosion performance of the cable are improved, the risk of cable cracking is reduced, and the potential safety hazard is reduced; the organic flame retardant and the inorganic flame retardant are added into the outer sheath at the same time and can play a synergistic role, so that the flame retardant property of the cable is enhanced; in conclusion, through optimization of the material formula and the structural design, the anti-cracking performance, the corrosion resistance, the mechanical strength and the flame retardant property of the cable are remarkably improved, and the cable has important application value in the technical field of cables.

Description

Technical Field

[0001] This invention belongs to the field of cable technology, specifically, it relates to a crack-resistant insulated cable. Background Technology

[0002] In power transmission and distribution systems, cables serve as the core carriers of electrical energy, and their performance directly affects the safe and stable operation of the power grid. With the rapid growth of electricity demand and the continuous expansion of the power grid, higher requirements are placed on the mechanical strength, insulation performance, and environmental adaptability of cables. However, traditional cables commonly suffer from insulation layer cracking during actual operation, severely impacting their service life and power supply reliability.

[0003] Traditional cables typically use polymer materials such as polyvinyl chloride (PVC) and cross-linked polyethylene (XLPE) for their insulation. While these materials possess good electrical insulation properties, they are prone to molecular chain breakage or microscopic defect propagation under long-term mechanical stress, temperature changes, and chemical corrosion, ultimately leading to macroscopic cracks in the insulation layer. Particularly in areas with large diurnal temperature differences or significant seasonal temperature variations, the cyclic stress generated by thermal expansion and contraction accelerates the aging process of the insulation material. Furthermore, cables must withstand bending and tensile forces during installation. If the insulation material lacks sufficient flexibility, microcracks can easily form during construction, creating potential problems for later operation. In addition, environmental factors significantly impact the crack resistance of cables. In coastal or industrially polluted areas, high concentrations of salt spray and acidic / alkaline substances in the air gradually corrode the cable surface, reducing the intermolecular forces of the insulation material; this causes the cable sheath to become brittle, inducing cracking and significantly shortening the cable's service life. Therefore, based on these issues, there is an urgent need to develop a crack-resistant insulated cable that combines mechanical strength and corrosion resistance. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide a crack-resistant insulated cable.

[0005] The objective of this invention can be achieved through the following technical solutions:

[0006] A crack-resistant insulated cable includes a conductor, an insulation layer, a shielding layer, and an outer sheath. The material of the outer sheath comprises the following raw materials in parts by weight: 88-100 parts of ethylene oxide rubber, 7-17 parts of corrosion inhibitor, 5-10 parts of organic flame retardant, 6-9 parts of inorganic flame retardant, 3-4 parts of processing aid, 2-3 parts of vulcanizing agent, and 0.4-0.8 parts of vulcanization accelerator.

[0007] Furthermore, the organic flame retardant is one of triphenyl phosphate, tricresyl phosphate, melamine phosphate, and melamine cyanurate.

[0008] Furthermore, the inorganic flame retardant is one of aluminum hydroxide and magnesium hydroxide.

[0009] Furthermore, the processing aid is one of paraffin wax, epoxidized soybean oil, and barium stearate.

[0010] Furthermore, the vulcanizing agent is one of di-tert-butyl peroxide and dicumyl peroxide.

[0011] Furthermore, the vulcanization accelerator is one of diphenylguanidine, zinc oxide, and triethanolamine.

[0012] Furthermore, the corrosion inhibitor is prepared through the following steps:

[0013] Step A1: 1,5-Dihydroxynaphthalene, allyl chloride, and N,N-dimethylformamide were added sequentially to a three-necked flask equipped with a magnetic stirrer, reflux condenser, dropping funnel, and thermometer. After stirring and mixing evenly, sodium hydroxide solution (20% by mass) was added dropwise to the flask through the dropping funnel. After the addition was complete, the apparatus was placed in a water bath and refluxed for 5 hours at 65°C. After the reaction was complete, the mixture was filtered, and some solvent was removed by vacuum concentration. The product was then purified by column chromatography using a benzene-ethyl acetate (2:1, v / v) elution system. Finally, residual eluent was removed by vacuum distillation to obtain the product containing double bonds.

[0014] Furthermore, in step A1, the ratio of the amounts of 1,5-dihydroxynaphthalene, allyl chloride, N,N-dimethylformamide, and sodium hydroxide solution is 17.6 g: 7.6 g: 100 mL: 20 mL.

[0015] The reaction principle of step A1 is as follows: sodium hydroxide can react with the hydroxyl group in the 1,5-dihydroxynaphthalene molecule to form sodium phenolate, and react with allyl chloride. The amount of both is strictly controlled to reduce side reactions.

[0016] The reaction formula for step A1 is as follows:

[0017]

[0018] Step A2: The product containing the double bond, hexafluoroglutaryl chloride, and anhydrous toluene were sequentially added to a three-necked flask equipped with a magnetic stirrer and a thermometer. After stirring and mixing evenly, triethylamine was added dropwise to the flask through a dropping funnel. After the addition was complete, the apparatus was placed in a water bath and the reaction was stirred for 10 hours under constant temperature water bath conditions of 75°C. After the reaction was complete, the mixture was filtered, and some solvent was removed by vacuum concentration. Then, column chromatography was performed to purify the product using a petroleum ether-ethyl acetate (5:1, v / v) elution system. Finally, residual eluent was removed by vacuum distillation to obtain the preservative enhancer.

[0019] Furthermore, in step A2, the ratio of the double-bonded product, hexafluoroglutaryl chloride, anhydrous toluene, and triethylamine is 42.2 g: 27.6 g: 150 mL: 20.2 g.

[0020] The reaction principle of step A2 is as follows: under the catalysis of triethylamine, the product containing the double bond undergoes an acylation reaction with hexafluoroglutaryl chloride, and the amounts of both are strictly controlled to ensure a complete reaction.

[0021] The reaction formula for step A2 is as follows:

[0022]

[0023] The prepared corrosion inhibitor molecule contains two naphthalene ring structures. Due to their intramolecular conjugation effect and high rigidity, they can significantly improve the modulus and strength of the material. The introduction of these groups can restrict the movement of polymer chain segments, reduce the relaxation behavior of molecular chains, and enhance the mechanical strength of the material. Introducing multiple CF bonds into the corrosion inhibitor molecule, due to their high bond energy and good stability, can also shield and protect the carbon chain, reduce the surface free energy of the matrix, and this effect can greatly enhance the corrosion resistance of the matrix. Finally, the corrosion inhibitor molecule introduces a double bond structure, which can cross-link with the matrix under the action of peroxide vulcanizing agents to form a cross-linked network structure. This not only further improves the mechanical strength of the material, but also improves the migration resistance of the small molecule corrosion inhibitor, making the performance of the corrosion inhibitor more stable.

[0024] The beneficial effects of this invention are:

[0025] The cable produced by this invention incorporates an anti-corrosion reinforcing agent as one of the raw materials in the outer sheath. This agent contains multiple functional groups, significantly improving the cable's mechanical strength and corrosion resistance, reducing the risk of cable cracking and micro-cracks caused by bending or stretching during cable laying, thus mitigating potential hazards during construction. Simultaneously, organic and inorganic flame retardants are added to the outer sheath, working synergistically to enhance the cable's flame retardant properties. In summary, this invention, through optimization of material formulation and structural design, significantly improves the cable's crack resistance, corrosion resistance, mechanical strength, and flame retardant properties, providing a reliable guarantee for the safe and stable operation of power transmission systems and possessing significant application value in the field of cable technology. Detailed Implementation

[0026] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1

[0028] Preparation of preservatives and enhancers:

[0029] Step A1: 17.6 g of 1,5-dihydroxynaphthalene, 7.6 g of allyl chloride, and 100 mL of N,N-dimethylformamide were sequentially added to a three-necked flask equipped with a magnetic stirrer, a reflux condenser, a dropping funnel, and a thermometer. After stirring and mixing thoroughly, 20 mL of sodium hydroxide solution (20% by mass) was added dropwise to the flask through the dropping funnel. After the addition was complete, the apparatus was placed in a water bath and refluxed at 65°C for 5 hours. After the reaction was complete, the mixture was filtered, and some solvent was removed by vacuum concentration. The product was then purified by column chromatography using a benzene-ethyl acetate (2:1, v / v) elution system. Finally, residual eluent was removed by vacuum distillation to obtain the product containing double bonds.

[0030] Step A2: 42.2g of the product containing double bonds, 27.6g of hexafluoroglutaryl chloride, and 150mL of anhydrous toluene were added sequentially to a three-necked flask equipped with a magnetic stirrer and a thermometer. After stirring and mixing evenly, 20.2g of triethylamine was added dropwise to the flask through a dropping funnel. After the addition was complete, the apparatus was placed in a water bath and the reaction was stirred for 10 hours under constant temperature water bath conditions of 75℃. After the reaction was complete, the mixture was filtered, and some solvent was removed by vacuum concentration. Then, column chromatography was performed to purify the product using a petroleum ether-ethyl acetate (5:1, v / v) elution system. Finally, residual eluent was removed by vacuum distillation to obtain the preservative enhancer.

[0031] Example 2

[0032] Preparation of preservatives and enhancers:

[0033] Step A1: 35.2g of 1,5-dihydroxynaphthalene, 15.2g of allyl chloride, and 200mL of N,N-dimethylformamide were sequentially added to a three-necked flask equipped with a magnetic stirrer, a reflux condenser, a dropping funnel, and a thermometer. After stirring and mixing thoroughly, 40mL of sodium hydroxide solution (20% by mass) was added dropwise to the flask through the dropping funnel. After the addition was complete, the apparatus was placed in a water bath and refluxed at 65℃ for 5 hours. After the reaction was complete, the mixture was filtered, and some solvent was removed by vacuum concentration. The product was then purified by column chromatography using a benzene-ethyl acetate (2:1, v / v) elution system. Finally, residual eluent was removed by vacuum distillation to obtain the product containing double bonds.

[0034] Step A2: 84.4g of the product containing double bonds, 55.2g of hexafluoroglutaryl chloride, and 300mL of anhydrous toluene were sequentially added to a three-necked flask equipped with a magnetic stirrer and a thermometer. After stirring and mixing evenly, 40.4g of triethylamine was added dropwise to the flask through a dropping funnel. After the addition was complete, the apparatus was placed in a water bath and the reaction was stirred for 10 hours under constant temperature water bath conditions of 75℃. After the reaction was complete, the mixture was filtered, and some solvent was removed by vacuum concentration. Then, column chromatography was performed to purify the product using a petroleum ether-ethyl acetate (5:1, v / v) elution system. Finally, residual eluent was removed by vacuum distillation to obtain the preservative enhancer.

[0035] Example 3

[0036] Materials used to prepare the outer sheath:

[0037] 88g of ethylene pyrolysis rubber, 7g of corrosion inhibitor prepared in Example 1, 5g of triphenyl phosphate, 6g of aluminum hydroxide, 3g of paraffin wax, 2g of di-tert-butyl peroxide and 0.4g of diphenylguanidine were added to a torque rheometer for melt blending. The melt blend was then vulcanized in a flat vulcanizing machine to obtain the material for the outer sheath.

[0038] Example 4

[0039] Materials used to prepare the outer sheath:

[0040] 94g of ethylene oxide rubber, 12g of the corrosion inhibitor prepared in Example 1, 7g of tricresyl phosphate, 8g of magnesium hydroxide, 3.5g of epoxidized soybean oil, 2.5g of dicumyl peroxide and 0.6g of zinc oxide were melt-blended in a torque rheometer, and the melt blend was vulcanized in a flat vulcanizing machine to obtain the material of the outer sheath.

[0041] Example 5

[0042] Materials used to prepare the outer sheath:

[0043] 100g of ethylene oxide rubber, 17g of the corrosion inhibitor prepared in Example 2, 10g of melamine phosphate, 9g of magnesium hydroxide, 4g of barium stearate, 3g of dicumyl peroxide and 0.8g of zinc oxide were melt-blended in a torque rheometer, and the melt blend was vulcanized in a flat vulcanizing machine to obtain the material of the outer sheath.

[0044] Example 6

[0045] Multiple strands of nickel-plated copper wire are twisted together to obtain a conductor. Polyethylene is then extruded onto the surface of the conductor through an extruder to form an insulation layer. A braided copper mesh is then tightly wrapped around the surface of the insulation layer. Finally, 100g of ethylene pyrolysis rubber, 17g of corrosion inhibitor prepared in Example 2, 10g of melamine phosphate, 9g of magnesium hydroxide, 4g of barium stearate, 3g of dicumyl peroxide, and 0.8g of zinc oxide are melt-blended in a torque rheometer. After extrusion, the mixture is vulcanized to obtain a crack-resistant insulated cable.

[0046] Comparative Example 1

[0047] The same quality of commercially available preservative was used to replace the preservative enhancer in Example 5, and the remaining steps were the same as in Example 5 to obtain the material.

[0048] Comparative Example 2

[0049] The same quality of commercially available reinforcing agent was used to replace the corrosion-resistant reinforcing agent in Example 5, and the remaining steps were the same as in Example 5 to obtain the material.

[0050] The following performance tests were conducted on Examples 3, 4, and 5, and Comparative Examples 1 and 2:

[0051] Tensile strength was determined according to the national standard GB / T 528 "Determination of tensile stress-strain properties of vulcanized rubber or thermoplastic rubber";

[0052] The tear strength was determined according to the national standard GB / T529 "Determination of tear strength of vulcanized rubber or thermoplastic rubber";

[0053] The tear strength of the samples after alkali treatment and acid treatment (GB / T 529) was determined, and the tear strength retention rate was calculated; tear strength retention rate = tear strength after test / tear strength before test × 100%;

[0054] Alkali treatment: Sodium hydroxide solution with a pH of 13, water bath at 55°C for 6 hours;

[0055] Acid treatment: immerse in a hydrochloric acid solution with a pH of 2 at 55°C for 6 hours.

[0056] After allowing Examples 3, 4, 5 and Comparative Example 2 to stand at room temperature for 12 months, the tear strength was measured again, and the tear strength retention rate was calculated.

[0057] The measurement results are shown in the table below:

[0058]

[0059]

[0060] As can be seen from the table above, the outer sheath material prepared by the embodiments of the present invention has high mechanical strength and good corrosion resistance. Both performance indicators are higher than those of the comparative example. Its performance remains stable after long-term storage. Therefore, using it as a component of a cable can improve the cable's crack resistance and corrosion resistance, and it has important application value in the field of cable technology.

[0061] In the description of this specification, the references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0062] The above description is merely an example and illustration of the present invention. Any modifications or additions made by those skilled in the art to the specific embodiments described, or any substitutions made in a similar manner, should fall within the protection scope of the present invention.

Claims

1. A crack-resistant insulated cable, comprising a conductor, an insulation layer, a shielding layer, and an outer sheath, characterized in that, The outer sheath is made of the following raw materials in parts by weight: 88-100 parts of ethylene oxide rubber, 7-17 parts of corrosion inhibitor, 5-10 parts of organic flame retardant, 6-9 parts of inorganic flame retardant, 3-4 parts of processing aid, 2-3 parts of vulcanizing agent, and 0.4-0.8 parts of vulcanization accelerator.

2. The crack-resistant insulated cable according to claim 1, characterized in that, The corrosion inhibitor is prepared by the following steps: Step A1: 1,5-Dihydroxynaphthalene, allyl chloride and N,N-dimethylformamide were added to the flask in sequence and stirred. After mixing, sodium hydroxide solution was added dropwise to the flask. After the addition was complete, the reaction was refluxed for 5 hours under a water bath at 65°C to obtain a product containing double bonds. Step A2: The product containing the double bond, hexafluoroglutaryl chloride, and anhydrous toluene are added sequentially to the flask and stirred. After mixing, triethylamine is added dropwise to the flask. After the addition is complete, the mixture is stirred at 75°C for 10 hours to complete the reaction and obtain the preservative enhancer.

3. The crack-resistant insulated cable according to claim 2, characterized in that, In step A1, the ratio of the amounts of 1,5-dihydroxynaphthalene, allyl chloride, N,N-dimethylformamide, and sodium hydroxide solution is 17.6 g: 7.6 g: 100 mL: 20 mL.

4. The crack-resistant insulated cable according to claim 2, characterized in that, In step A2, the ratio of the product containing the double bond, hexafluoroglutaryl chloride, anhydrous toluene, and triethylamine is 42.2 g: 27.6 g: 150 mL: 20.2 g.

5. The crack-resistant insulated cable according to claim 1, characterized in that, The organic flame retardant is one of triphenyl phosphate, tricresyl phosphate, melamine phosphate, and melamine cyanurate.

6. The crack-resistant insulated cable according to claim 1, characterized in that, The inorganic flame retardant is one of aluminum hydroxide and magnesium hydroxide.

7. The crack-resistant insulated cable according to claim 1, characterized in that, The processing aid is one of paraffin wax, epoxidized soybean oil, and barium stearate.

8. The crack-resistant insulated cable according to claim 1, characterized in that, The vulcanizing agent is one of di-tert-butyl peroxide and dicumyl peroxide.

9. The crack-resistant insulated cable according to claim 1, characterized in that, The vulcanization accelerator is one of diphenylguanidine, zinc oxide, and triethanolamine.

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