A long-life cable for nuclear power

Abstract

The present invention relates to the field of cable technology and proposes a long-life cable for nuclear power use. The cable comprises, from the inside out, a conductor, an insulation layer, a shielding layer, and a sheath layer. The sheath layer comprises the following components by weight: 60-70 parts high-density polyethylene, 12-22 parts carboxylated nitrile rubber, 4-8 parts styrene-acrylonitrile copolymer, 0.5-8 parts copper-based metal organic complex, 8-15 parts palygorskite powder, 2-5 parts zinc oxide, 0.5-1.3 parts antioxidant, 1-3 parts plasticizer, and 0.2-0.5 parts vulcanizing agent. The copper-based metal organic complex comprises copper trifluoromethanesulfonate and copper acetylacetonate in a weight ratio of 1-3:1. This technical solution solves the problem of poor aging resistance of sheath layers in nuclear power cables in the related art.

Description

Technical Field

[0001] The present invention relates to the technical field of cables, and in particular to a long-life cable for nuclear power. Background Art

[0002] Nuclear power plants operate in complex environments. Cables, key components for power transmission and signal control, are exposed to extreme conditions such as high radiation, high temperature, high humidity, and strong electromagnetic interference. This places extremely high demands on cable performance and lifespan. Traditional cable materials are prone to aging, mechanical degradation, and insulation failure in such harsh environments, seriously impacting the safe and stable operation of nuclear power plants.

[0003] Currently, the sheathing layer of nuclear power cables typically uses high-density polyethylene or rubber as a matrix, with fillers and additives added to enhance aging resistance, radiation resistance, and mechanical properties. However, the unsaturated double bonds in the molecular chains of some unsaturated rubber materials are susceptible to oxidation reactions under high temperatures and radiation, leading to material degradation. To address this issue, existing technologies typically use vulcanization systems or add stabilizing additives to inhibit rubber aging, but these methods are ineffective in reducing cable sheath aging.

[0004] Therefore, developing a long-life cable for nuclear power can effectively improve the aging resistance of the cable sheath layer, which is of great significance for extending the service life of nuclear power cables and meeting the needs of long-term stable operation of nuclear power plants. Summary of the Invention

[0005] The present invention provides a long-life cable for nuclear power, which solves the problem of poor aging resistance of the sheath layer of the nuclear power cable in the related art.

[0006] The technical solutions of the present invention are as follows:

[0007] The present invention provides a long-life cable for nuclear power, which comprises, from the inside to the outside, a conductor, an insulation layer, a shielding layer, and a sheath layer. The sheath layer comprises the following components in parts by weight:

[0008] 60-70 parts of high-density polyethylene, 12-22 parts of carboxylated nitrile rubber, 4-8 parts of styrene-acrylonitrile copolymer, 0.5-8 parts of copper metal organic complex, 8-15 parts of palygorskite powder, 2-5 parts of zinc oxide, 0.5-1.3 parts of antioxidant, 1-3 parts of plasticizer, and 0.2-0.5 parts of vulcanizing agent;

[0009] The copper-based metal organic complex comprises copper trifluoromethanesulfonate and copper acetylacetonate in a weight ratio of 1 to 3:1.

[0010] In the present invention, the sheath layer of the long-life nuclear power cable is mainly based on high-density polyethylene, which provides basic strength and stability for the sheath layer, so that it will not be easily damaged in the nuclear power environment. At the same time, under the combined action of carboxyl nitrile rubber, styrene-acrylonitrile copolymer, copper metal organic complex, palygorskite powder, zinc oxide, antioxidant, plasticizer, and vulcanizing agent, a sheath layer with good aging resistance can be prepared, thereby effectively protecting the long-life nuclear power cable and extending the service life of the nuclear power cable.

[0011] Among them, carboxyl nitrile rubber itself has good oil resistance and wear resistance. When combined with high-density polyethylene, it can improve the overall performance of the sheath layer of long-life nuclear power cables. Palygorskite powder can be added to the sheath layer of long-life nuclear power cables as a reinforcing filler. Through the interaction between the palygorskite powder and the various components in the sheath layer, it helps to improve the mechanical properties of the sheath layer of long-life nuclear power cables.

[0012] The sheath material of the long-life cable for nuclear power will inevitably undergo oxidation reaction under high temperature and high humidity environment, resulting in reduced mechanical strength and poor stability of the sheath material. In the present invention, an antioxidant is added. Since the antioxidant can capture free radicals, it slows down the oxidative degradation rate of the sheath material of the long-life cable for nuclear power, thereby helping to improve the stability of the sheath material and extend the service life of the cable. The antioxidant is a conventional antioxidant in the field, for example, it can be one or more of antioxidant 245, antioxidant 1024, antioxidant 1010, antioxidant 1076, antioxidant 626, and antioxidant 4020.

[0013] The addition of plasticizer can reduce the melt viscosity and glass transition temperature of the long-life cable sheath material to a certain extent, making the sheath material easier to flow and form during processing. At the same time, the plasticizer can be more compatible with the various components in the sheath, making the entire sheath system more uniform and stable. The plasticizer is a conventional plasticizer in the field, for example, dioctyl phthalate, dibutyl phthalate, tricresyl phosphate, dioctyl sebacate, dioctyl adipate;

[0014] In the present invention, the addition of a vulcanizing agent to the sheath layer of the long-life cable for nuclear power helps the carboxyl nitrile rubber to form a cross-linked structure, thereby improving the stability of the carboxyl nitrile rubber to a certain extent. The vulcanizing agent is a conventional vulcanizing agent in the art, for example, sulfur or dicumyl peroxide.

[0015] As a further technical solution, the weight ratio of the carboxyl nitrile rubber to the copper metal organic complex is 20:2-5, for example, 20:2, 20:3, 20:4, 20:5, preferably 20:2, 20:5.

[0016] In the present invention, a copper-based metal organic complex is allowed to act on a carboxyl nitrile rubber, and the weight ratio of the copper-based metal organic complex to the carboxyl nitrile rubber is rationally regulated. When the weight ratio of the carboxyl nitrile rubber to the copper-based metal organic complex is 20:2-5, the aging resistance of the sheath layer of a long-life cable for nuclear power can be further improved, so that the tensile strength after aging is increased to 25.1-25.6 MPa. When the weight ratio of the carboxyl nitrile rubber to the copper-based metal organic complex is outside the range of 20:2-5, the effect of improving the aging resistance of the sheath layer of the long-life cable for nuclear power is slightly poor.

[0017] As a further technical solution, the conductor is made of one of aluminum alloy and copper alloy.

[0018] Conductors, as carriers of electrical energy or signal transmission, directly determine the applicability of long-life cables for nuclear power in actual use. In the present invention, the material of the conductor is aluminum alloy or copper alloy. Aluminum alloy or copper alloy gives the conductor good electrical conductivity. At the same time, aluminum alloy conductors and copper alloy conductors can withstand certain external forces, which can ensure that long-life cables for nuclear power can stably transmit electricity in high temperature, low temperature and other more severe environments.

[0019] As a further technical solution, the insulating layer is a polyvinyl chloride insulating layer;

[0020] The shielding layer is a copper wire braided shielding layer.

[0021] In the present invention, the insulation layer of the long-life cable for nuclear power is a polyvinyl chloride insulation layer. Polyvinyl chloride itself has good resistivity, which can prevent current leakage while protecting the conductor. Combined with the copper wire braided shielding layer and the sheath layer, it can effectively improve the overall stability of the long-life cable for nuclear power.

[0022] The shielding layer is a copper wire braided shielding layer, which can effectively prevent the complex and strong electromagnetic environment inside the nuclear power plant from affecting the signals or electrical energy transmitted inside the cable. At the same time, the copper wire braided shielding layer has a certain mechanical strength and can protect the insulation layer and conductor inside the cable to a certain extent.

[0023] As a further technical solution, the vulcanizing agent includes dicumyl peroxide.

[0024] In the present invention, the vulcanizing agent is preferably dicumyl peroxide. Dicumyl peroxide has a fast vulcanization speed and can make the carboxylated nitrile rubber reach the required degree of vulcanization in a relatively short time, thereby improving production efficiency. At the same time, compared with the vulcanization system formed by sulfur, the dicumyl peroxide-free vulcanization system has better stability for the carboxylated nitrile rubber.

[0025] As a further technical solution, the antioxidant includes one or more of antioxidant 245 , antioxidant 1024 , and antioxidant 1010 .

[0026] In the present invention, the structures of antioxidant 245, antioxidant 1024, and antioxidant 1010 are relatively stable, and their own antioxidant life is relatively long. When the antioxidant includes one or more of antioxidant 245, antioxidant 1024, and antioxidant 1010, it can more effectively prevent the oxidative degradation of the cable sheath layer material, thereby improving the service life of the nuclear power cable sheath layer.

[0027] As a further technical solution, the plasticizer includes one or more of dioctyl phthalate, tricresyl phosphate, and dioctyl sebacate.

[0028] In the present invention, among conventional plasticizers in the field, dioctyl phthalate, tricresyl phosphate, and dioctyl sebacate have good compatibility with the components in the sheath layer, which can better improve the processing performance of the sheath layer material of the nuclear power cable and enhance its stability.

[0029] As a further technical solution, the palygorskite powder is intercalation-modified palygorskite powder, and the raw materials of the intercalation-modified palygorskite powder include palygorskite powder and hydroxyl-terminated polyethersulfone.

[0030] Palygorskite powder interacts with the various components in the sheath layer. When the amount of palygorskite powder is relatively too large, the hardness increases and it is easy to agglomerate, which will increase the compression permanent deformation of the sheath layer material, especially the rubber material, and reduce the overall low-temperature resistance of the sheath layer. Reducing the amount of palygorskite powder will affect its supporting and reinforcing effect on the overall sheath layer. In the present invention, the palygorskite powder is intercalated and modified using terminal hydroxyl polyether sulfone to improve the dispersion of the palygorskite powder in the sheath layer system, thereby ensuring the strength performance of the sheath layer of long-life cables for nuclear power while also improving the low-temperature resistance of the sheath layer.

[0031] As a further technical solution, the hydroxy-terminated polyethersulfone is 9% to 12% of the weight of the palygorskite powder, for example, 9%, 10%, 11%, 12%, preferably 9% or 12%.

[0032] In the present invention, when the hydroxy-terminated polyethersulfone accounts for 9% to 12% by weight of the palygorskite powder, the low-temperature resistance of the sheath layer of a long-life nuclear power cable can be further improved, so that the elongation at break of the sheath layer at a low temperature of -40°C is increased to 127% to 131%.

[0033] As a further technical solution, the preparation method of the intercalated modified palygorskite powder comprises the following steps:

[0034] A1, dispersing the palygorskite powder in dimethylformamide, uniformly dispersing the powder to obtain a suspension;

[0035] A2, dissolving the hydroxy-terminated polyethersulfone in dimethylformamide, mixing uniformly, to obtain a mixed solution;

[0036] A3. Adding the mixed solution to the suspension, mixing evenly, concentrating, and drying to obtain intercalated modified palygorskite powder.

[0037] As a further technical solution, in step A1, when the dispersion is uniform, stirring is performed at 200-300 rpm for 20-30 minutes.

[0038] As a further technical solution, in step A2, when the mixing is uniform, stirring is performed at 200-300 rpm and 50-60° C. for 30-40 minutes.

[0039] As a further technical solution, in step A3, when the mixing is uniform, stirring is performed at 100-200 rpm and 40-50° C. for 30-40 min.

[0040] The present invention also provides a method for preparing a long-life cable for nuclear power, which is used to prepare the long-life cable for nuclear power, comprising the following steps:

[0041] S1, extruding the insulating layer and coating it on the outside of the conductor to form an insulating layer with the conductor wrapped inside;

[0042] S2. Wrapping the shielding layer around the outer side of the inner insulating layer with the conductor to form a semi-finished cable;

[0043] S3. After the carboxyl nitrile rubber and the copper metal organic complex are evenly mixed, the remaining components in the sheath layer are added, the mixture is blended, extruded and coated on the periphery of the semi-finished cable, and vulcanized to obtain a long-life cable for nuclear power.

[0044] The working principle and beneficial effects of the present invention are:

[0045] In the present invention, a copper-based metal organic complex is added to the sheath layer of a long-life nuclear power cable. The copper-based metal organic complex stabilizes carboxylated nitrile rubber, thereby improving the aging resistance of the sheath layer of the long-life nuclear power cable. Currently, carboxylated nitrile rubber in cable sheaths is susceptible to aging due to the presence of unsaturated double bonds. To address this issue, a vulcanization system alone or a combination of a fatty acid salt stabilizing agent and a vulcanization system is typically used to inhibit the aging of the carboxylated nitrile rubber. However, the effectiveness of the vulcanization system alone in inhibiting rubber aging is limited, and the fatty acid salt stabilizing agent can be contaminated by vulcanization. Therefore, the effectiveness of the combination of a fatty acid salt stabilizing agent and a vulcanization system in inhibiting rubber aging still needs to be improved. The present invention takes into account the combined use of a vulcanization system and a stabilizing agent, and adopts a copper-based metal organic complex as a stabilizing agent for the carboxyl nitrile rubber. This can reduce direct contact between the carboxyl nitrile rubber and active free radicals, avoid the vulcanization process affecting the stabilizing effect of the copper-based metal organic complex itself, and effectively improve the aging resistance of the carboxyl nitrile rubber, thereby improving the aging resistance of the sheath layer of a long-life cable for nuclear power. DETAILED DESCRIPTION

[0046] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0047] In the following embodiments and comparative examples, in the polyvinyl chloride insulation layer, the model of polyvinyl chloride is NI00-50; the model of high-density polyethylene is DMDA-8008H; the model of carboxyl nitrile rubber is 1072CG; copper trifluoromethanesulfonate, CAS No. 34946-82-2; copper acetylacetonate, CAS No. 13395-16-9; the model of styrene-acrylonitrile copolymer is NF2200AR; the average particle size of palygorskite powder is 45 μm; the model of hydroxyl-terminated polyethersulfone is VW-10300FP, purchased from Dongguan Dongli Plastic Raw Materials Co., Ltd.

[0048] Example 1

[0049] A method for preparing a long-life cable for nuclear power, comprising the following steps:

[0050] S1. Extruding a polyvinyl chloride insulation layer and coating it on the outer side of the aluminum alloy conductor to form an inner polyvinyl chloride insulation layer with the aluminum alloy conductor coated thereon;

[0051] S2. Wrapping the copper wire braided shielding layer around the outer side of the polyvinyl chloride insulation layer with the inner layer wrapped with the aluminum alloy conductor to form a semi-finished cable;

[0052] S3. Mix 12 parts of carboxyl nitrile rubber, 0.25 parts of copper trifluoromethanesulfonate and 0.25 parts of copper acetylacetonate, then add 60 parts of high-density polyethylene, 4 parts of styrene-acrylonitrile copolymer, 8 parts of palygorskite powder, 2 parts of zinc oxide, 0.5 parts of antioxidant 245, 1 part of dioctyl phthalate and 0.2 parts of diisopropylbenzene peroxide, extrude and coat the mixture on the outer periphery of the cable semi-finished product, and vulcanize to obtain a long-life cable for nuclear power.

[0053] Example 2

[0054] A method for preparing a long-life cable for nuclear power, comprising the following steps:

[0055] S1. Extruding a polyvinyl chloride insulation layer and coating it on the outer side of the aluminum alloy conductor to form an inner polyvinyl chloride insulation layer with the aluminum alloy conductor coated thereon;

[0056] S2. Wrapping the copper wire braided shielding layer around the outer side of the polyvinyl chloride insulation layer with the inner layer wrapped with the aluminum alloy conductor to form a semi-finished cable;

[0057] S3. Mix 20 parts of carboxyl nitrile rubber, 4.5 parts of copper trifluoromethanesulfonate and 1.5 parts of copper acetylacetonate, then add 65 parts of high-density polyethylene, 6 parts of styrene-acrylonitrile copolymer, 10 parts of palygorskite powder, 3 parts of zinc oxide, 1 part of antioxidant 1010, 2 parts of tricresyl phosphate and 0.3 part of dicumyl peroxide, extrude and coat the mixture on the outer periphery of the cable semi-finished product, and vulcanize to obtain a long-life cable for nuclear power.

[0058] Example 3

[0059] A method for preparing a long-life cable for nuclear power, comprising the following steps:

[0060] S1. Extruding a polyvinyl chloride insulation layer and coating it on the outer side of the aluminum alloy conductor to form an inner polyvinyl chloride insulation layer with the aluminum alloy conductor coated thereon;

[0061] S2. Wrapping the copper wire braided shielding layer around the outer side of the polyvinyl chloride insulation layer with the inner layer wrapped with the aluminum alloy conductor to form a semi-finished cable;

[0062] S3. Mix 22 parts of carboxyl nitrile rubber, 5 parts of copper trifluoromethanesulfonate and 3 parts of copper acetylacetonate, then add 70 parts of high-density polyethylene, 8 parts of styrene-acrylonitrile copolymer, 15 parts of palygorskite powder, 5 parts of zinc oxide, 1.3 parts of antioxidant 1024, 3 parts of dioctyl sebacate and 0.5 part of diisopropylbenzene peroxide, extrude and coat the mixture on the outer periphery of the cable semi-finished product, and vulcanize to obtain a long-life cable for nuclear power.

[0063] Example 4

[0064] The only difference between this embodiment and embodiment 2 is that, in this embodiment, 3 parts of copper trifluoromethanesulfonate and 3 parts of copper acetylacetonate are added.

[0065] Example 5

[0066] The only difference between this embodiment and embodiment 2 is that, in this embodiment, 0.75 parts of copper trifluoromethanesulfonate and 0.25 parts of copper acetylacetonate are added.

[0067] Example 6

[0068] The only difference between this embodiment and embodiment 2 is that, in this embodiment, 1.5 parts of copper trifluoromethanesulfonate and 0.5 parts of copper acetylacetonate are added.

[0069] Example 7

[0070] The only difference between this embodiment and embodiment 2 is that, in this embodiment, 3.75 parts of copper trifluoromethanesulfonate and 1.25 parts of copper acetylacetonate are added.

[0071] Example 8

[0072] The only difference between this embodiment and embodiment 7 is that, in this embodiment, the palygorskite powder is intercalation-modified palygorskite powder, and the preparation method of the intercalation-modified palygorskite powder comprises the following steps:

[0073] A1. Disperse 10 parts of palygorskite powder in 20 parts of dimethylformamide, stir at 250 rpm for 25 min, and disperse uniformly to obtain a suspension;

[0074] A2. Dissolve 1.5 parts of hydroxy-terminated polyethersulfone in 5 parts of dimethylformamide, stir at 200 rpm and 55° C. for 35 minutes, and mix well to obtain a mixed solution;

[0075] A3, adding the mixed solution to the suspension, stirring at 150 rpm and 45° C. for 35 min, mixing evenly, concentrating, and drying to obtain intercalated modified palygorskite powder;

[0076] A method for preparing a long-life cable for nuclear power, comprising the following steps:

[0077] S1. Extruding a polyvinyl chloride insulation layer and coating it on the outer side of the aluminum alloy conductor to form an inner polyvinyl chloride insulation layer with the aluminum alloy conductor coated thereon;

[0078] S2. Wrapping the copper wire braided shielding layer around the outer side of the polyvinyl chloride insulation layer with the inner layer wrapped with the aluminum alloy conductor to form a semi-finished cable;

[0079] S3. Mix 20 parts of carboxyl nitrile rubber, 3.75 parts of copper trifluoromethanesulfonate and 1.25 parts of copper acetylacetonate evenly, then add 65 parts of high-density polyethylene, 6 parts of styrene-acrylonitrile copolymer, 10 parts of intercalated modified palygorskite powder, 3 parts of zinc oxide, 1 part of antioxidant 1024, 2 parts of tricresyl phosphate and 0.3 part of diisopropylbenzene peroxide, extrude and coat the mixture on the periphery of the cable semi-finished product, and vulcanize to obtain a long-life cable for nuclear power.

[0080] Example 9

[0081] The only difference between this embodiment and embodiment 8 is that in the preparation process of the intercalated modified palygorskite powder in this embodiment, 0.5 parts of the hydroxyl-terminated polyether is added.

[0082] Example 10

[0083] The only difference between this embodiment and embodiment 8 is that in the preparation process of the intercalated modified palygorskite powder in this embodiment, 0.9 parts of the hydroxyl-terminated polyether is added.

[0084] Example 11

[0085] The only difference between this embodiment and embodiment 8 is that in the preparation process of the intercalated modified palygorskite powder in this embodiment, 1.2 parts of the hydroxyl-terminated polyether is added.

[0086] Comparative Example 1

[0087] The only difference between this comparative example and Example 2 is that, in this comparative example, copper trifluoromethanesulfonate and copper acetylacetonate are replaced by an equal amount of zinc stearate.

[0088] Comparative Example 2

[0089] The only difference between this comparative example and Example 2 is that, in this comparative example, copper trifluoromethanesulfonate and copper acetylacetonate are replaced by an equal amount of copper stearate.

[0090] Comparative Example 3

[0091] The only difference between this comparative example and Example 2 is that, in this comparative example, copper trifluoromethanesulfonate is replaced by an equal amount of copper acetylacetonate.

[0092] Comparative Example 4

[0093] The only difference between this comparative example and Example 2 is that, in this comparative example, copper acetylacetonate is replaced by an equal amount of copper trifluoromethanesulfonate.

[0094] Comparative Example 5

[0095] The only difference between this comparative example and Example 2 is that in this comparative example, no copper metal organic complex is added;

[0096] In the method for preparing a long-life cable for nuclear power, step S3 is specifically as follows:

[0097] S3. Blend 20 parts of carboxyl nitrile rubber, 65 parts of high-density polyethylene, 6 parts of styrene-acrylonitrile copolymer, 10 parts of palygorskite powder, 3 parts of zinc oxide, 1 part of antioxidant 1024, 2 parts of tricresyl phosphate, and 0.3 parts of dicumyl peroxide, and extrude and coat the mixture on the outer periphery of a semi-finished cable after vulcanization to obtain a long-life cable for nuclear power.

[0098] Experimental Example 1 Aging resistance test

[0099] Three samples were cut from the sheath layer of the long-life cables for nuclear power prepared in Examples 1 to 7 and Comparative Examples 1 to 5, and dumbbell specimens with a thickness of 2 mm were prepared according to the method in GB / T 2951.11-2008 "General test methods for insulation and sheath materials of electric and optical cables Part 11: General test methods for thickness and dimensional measurements - Mechanical properties tests" to test the tensile strength before aging.

[0100] Three specimens were cut from the sheath layer of the long-life cables for nuclear power prepared in Examples 1 to 7 and Comparative Examples 1 to 5, and dumbbell specimens with a thickness of 2 mm were prepared according to the method in GB / T 2951.11-2008 "General test methods for insulation and sheath materials of electric and optical cables Part 11: General test methods for thickness and dimensional measurement - Mechanical properties test". An aging resistance test was then performed, and the tensile strength test after aging was performed according to the above method. The aging resistance test method was an air oven aging method at a temperature of 135°C for 240 h.

[0101] The test results are shown in Table 1:

[0102] Table 1 Aging resistance test results of Examples 1 to 7 and Comparative Examples 1 to 5

[0103]

[0104] As can be seen from Table 1, compared with Comparative Examples 1 to 5, the sheath layers of the long-life cables for nuclear power prepared in Examples 1 to 7 have a higher tensile strength retention rate after the thermal aging test. According to the formula tensile strength retention rate = tensile strength after aging / tensile strength before aging × 100%, the tensile strength retention rates of the sheath layers of Examples 1 to 7 reach more than 93%, indicating that copper trifluoromethanesulfonate and copper acetylacetonate are added to the sheath layer, and the aging resistance of the sheath layer can be improved by the combined use of copper trifluoromethanesulfonate and copper acetylacetonate.

[0105] Experimental Example 2 Low temperature resistance test

[0106] Three specimens were cut from the sheath layer of each of the long-life cables for nuclear power prepared in Examples 7 to 11. After low-temperature testing according to the method in GB / T 2951.14-2008 "General test methods for insulation and sheath materials of electric and optical cables Part 14: General test methods, low-temperature tests", the sheath layer was subjected to a -40°C low-temperature tensile test for elongation at break. The test results are shown in Table 2.

[0107] Table 2 Low temperature resistance test results of Examples 7 to 11

[0108]

[0109] As can be seen from Table 2, compared with Example 7, the elongation at break of the sheath layer of Examples 8 to 11 at a low temperature of -40°C is improved, reaching more than 116%, indicating that the intercalation modification treatment of palygorskite powder with terminated hydroxyl polyether sulfone can improve the low temperature resistance of the sheath layer of the long-life cable for nuclear power use.

[0110] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A long-life cable for nuclear power, comprising, from the inside to the outside, a conductor, an insulation layer, a shielding layer, and a sheath layer, characterized in that: The sheath layer comprises the following components in parts by weight: 60-70 parts of high-density polyethylene, 12-22 parts of carboxylated nitrile rubber, 4-8 parts of styrene-acrylonitrile copolymer, 0.5-8 parts of copper metal organic complex, 8-15 parts of palygorskite powder, 2-5 parts of zinc oxide, 0.5-1.3 parts of antioxidant, 1-3 parts of plasticizer, and 0.2-0.5 parts of vulcanizing agent; The copper-based metal organic complex comprises copper trifluoromethanesulfonate and copper acetylacetonate in a weight ratio of 1 to 3:1; The method for preparing the long-life cable for nuclear power comprises the following steps: S1, extruding the insulating layer and coating it on the outside of the conductor to form an insulating layer with the conductor wrapped inside; S2. Wrapping the shielding layer around the outer side of the inner insulating layer with the conductor to form a semi-finished cable; S3. After the carboxyl nitrile rubber and the copper metal organic complex are evenly mixed, the remaining components in the sheath layer are added, the mixture is blended, extruded and coated on the periphery of the semi-finished cable, and vulcanized to obtain a long-life cable for nuclear power.

2. A long-life cable for nuclear power according to claim 1, characterized in that: The weight ratio of the carboxyl nitrile rubber to the copper metal organic complex is 20:2-5.

3. A long-life cable for nuclear power according to claim 1, characterized in that: The conductor is made of aluminum alloy or copper alloy.

4. A long-life cable for nuclear power according to claim 1, characterized in that: The insulating layer is a polyvinyl chloride insulating layer; The shielding layer is a copper wire braided shielding layer.

5. The long-life cable for nuclear power according to claim 1, characterized in that: The vulcanizing agent is dicumyl peroxide.

6. The long-life cable for nuclear power according to claim 1, characterized in that: The antioxidant includes one or more of antioxidant 245 , antioxidant 1024 , and antioxidant 1010 .

7. The long-life cable for nuclear power according to claim 1, characterized in that: The plasticizer includes one or more of dioctyl phthalate, tricresyl phosphate, and dioctyl sebacate.

8. The long-life cable for nuclear power according to claim 1, characterized in that: The palygorskite powder is intercalation-modified palygorskite powder, and the raw materials of the intercalation-modified palygorskite powder include palygorskite powder and hydroxyl-terminated polyethersulfone.

9. A long-life cable for nuclear power according to claim 8, characterized in that: The hydroxyl-terminated polyethersulfone accounts for 9% to 12% of the weight of the palygorskite powder.

10. The long-life cable for nuclear power according to claim 8, characterized in that: The preparation method of the intercalated modified palygorskite powder comprises the following steps: A1, dispersing the palygorskite powder in dimethylformamide, uniformly dispersing the powder to obtain a suspension; A2, dissolving the hydroxy-terminated polyethersulfone in dimethylformamide, mixing uniformly, to obtain a mixed solution; A3. Adding the mixed solution to the suspension, mixing evenly, concentrating, and drying to obtain intercalated modified palygorskite powder.

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