Semiconductive resin composition for extra-high voltage cables with excellent processability and method for producing the same

Abstract

The present invention relates to a semiconductive resin composition for high-voltage power cables. Specifically, the present invention relates to a semiconductive resin composition containing a base resin in which ethylene butyl acrylates having different melt indices are mixed, carbon black, an antioxidant, and a crosslinking agent. The present invention also relates to a semiconductive resin composition for high-voltage power cables having excellent scorch stability and processability, and low volume resistivity even at high temperatures.

Description

[Technical Field]

[0001] The present invention relates to a semiconductive resin composition for high-voltage power cables, and more specifically to a semiconductive resin composition for high-voltage power cables that has excellent scorch stability and processability and low volume resistivity even at high temperatures. [Background technology]

[0002] Generally, power cables are composed of a conductor made of a metal such as aluminum or copper, covered with an inner semiconductive layer that encases the conductor, then covered with an insulating layer, followed by an outer semiconductive layer and an armor layer placed on the outer semiconductive layer to protect the cable itself, and the structure may be changed as needed.

[0003] The purpose of using the semiconductive layer is to radially homogenize the local electric field, which can cause high voltages to be applied to the insulating layer due to electric field distortion that occurs between the conductor and the neutral conductor, and to prevent insulation breakdown and shortened lifespan of the power cable due to deterioration of the insulating layer.

[0004] The semiconductive layer may contain a sufficient amount of carbon black, a peroxide crosslinker, and conventional additives to render the ethylene copolymer, such as ethylene vinyl acetate copolymer (EVA) or ethylene butyl acrylate (EBA), semiconductive, so as to faithfully perform its intended function in constructing a power cable.

[0005] The volume resistance of the semiconductive layer increases as the temperature rises. This is because the conductive network of the semiconductive material is destroyed by the temperature, blocking the passage of electrons, resulting in an increase in volume resistance.

[0006] Therefore, a conductive material such as carbon black is further added to reduce the volume resistivity, but this can result in a decrease in processability and mechanical strength.

[0007] In addition, different types of polymer resins can be mixed to improve processability, but this can reduce the miscibility between the semiconductive layer compositions and potentially reduce surface smoothness. Furthermore, additives can be added to improve processability, but this can incur additional costs and can be difficult to mix uniformly, making it difficult to adopt industrially.

[0008] Therefore, there is a strong need in the art for a semiconductive composition for forming a semiconductive layer that is excellent in processability and mechanical strength, and at the same time exhibits sufficient semiconductive properties. Summary of the Invention [Problem to be solved by the invention]

[0009] In order to solve the above problems, the present invention provides a semiconductive layer composition that has excellent processability and miscibility, as well as excellent mechanical strength, without using a base resin that is a mixture of different types of polymers or adding additional carbon black, and in particular, provides a semiconductive layer composition that has low surface smoothness and low volume resistivity at high temperatures. [Means for solving the problem]

[0010] The present invention provides a semiconductive resin composition comprising a base resin in which two types of ethylene butyl acrylate resins having melt indices satisfying the following formulas 1 and 2 are mixed, carbon black, an antioxidant, and a crosslinking agent.

[0011]

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[0012] According to one embodiment of the present invention, the MI1 value and the MI2 value of the base resin can satisfy the following formula 3.

[0013]

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[0014] According to one aspect of the present invention, the first ethylene butyl acrylate resin in the base resin is an ethylene butyl acrylate copolymer having a content of structural units derived from butyl acrylate monomer of 15 to 18 mol% and a melt index of 5 to 10 g / 10 min, The second ethylene butyl acrylate resin may be an ethylene butyl acrylate copolymer having a content of structural units derived from butyl acrylate monomer of 19 to 22 mol% and a melt index of 17 to 22 g / 10 min.

[0015] According to one aspect of the present invention, the antioxidant may include at least one selected from a phenol-based compound and a thioether-based compound.

[0016] According to one aspect of the present invention, the semiconductive resin composition may further contain a metal stearate.

[0017] According to one aspect of the present invention, the metal stearates may include zinc stearate, calcium stearate, aluminum stearate, and magnesium stearate.

[0018] According to one embodiment of the present invention, the composition can contain 30 to 100 parts by weight of carbon black, 0.01 to 5 parts by weight of an antioxidant, and 0.1 to 10 parts by weight of a crosslinking agent relative to 100 parts by weight of the base resin.

[0019] According to one aspect of the present invention, there is provided a semiconductive resin cured product obtained by crosslinking the semiconductive resin composition.

[0020] According to one aspect of the present invention, the cured semiconductive resin may have a crosslink density of 15 dNm or more as measured by a moving die rheometer (MDR).

[0021] According to one aspect of the present invention, the semiconductive resin cured product may have a volume resistivity of 130 Ω·cm or less at 135° C. according to ASTM D991.

[0022] According to one aspect of the present invention, there can be provided a method for producing a cured semiconductive resin, the method including: a) adding the base resin, carbon black, and antioxidant of paragraph 1 to a first kneader and kneading them to produce a composite resin; b) producing the composite resin in the form of composite resin chips; c) adding the composite resin chips and a crosslinker to a second kneader and mixing them to produce a semiconductive resin composition; and d) crosslinking and maturing the semiconductive resin composition to provide a cured semiconductive resin.

[0023] According to one aspect of the present invention, the crosslinking time in step d) may be 10 minutes or more. [Effects of the Invention]

[0024] The semiconductive resin composition according to the present invention is prepared by mixing ethylene butyl acrylates having different melt indices to form a base resin, and contains an oxidizing agent and carbon black having a specific structure, thereby providing a semiconductive composition having excellent miscibility and also excellent mechanical strength such as tensile strength and elongation.

[0025] In addition, the semiconductive composition can reduce the volume resistivity by controlling only the melt index of the ethylene butyl acrylate, and there is no need to add a conductive material to reduce the resistivity.

[0026] In addition, the semiconductive composition can achieve optimal volume resistance at high temperatures while maintaining excellent mechanical strength and processability by controlling the content of unit structures containing butyl acrylate monomers in ethylene butyl acrylate. DETAILED DESCRIPTION OF THE INVENTION

[0027] The present invention will be described in more detail below with reference to specific examples or embodiments including the accompanying drawings. However, the following specific examples or embodiments are merely references for explaining the present invention in detail, and the present invention is not limited thereto and may be implemented in various forms.

[0028] Furthermore, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by those skilled in the art to which this invention belongs. The terms used in the description of the present invention are for the purpose of effectively describing specific embodiments and are not intended to limit the present invention.

[0029] Also, as used in the specification and the appended claims, the singular forms "a," "an," and "the" can be intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0030] Also, when a part is said to "comprise" a certain component, this does not mean that it excludes other components, but that it may further include other components, unless specifically stated to the contrary.

[0031] Furthermore, the high temperature described in the present invention means a temperature of 90°C or higher.

[0032] The inventors of the present invention have discovered that by providing a semiconductive composition containing a base resin in which ethylene butyl acrylates having different melting indices are mixed, it is possible to provide a semiconductive composition having excellent mechanical properties and processability as well as excellent volume resistivity without the addition of any additives or conductive materials, and have thus completed the present invention.

[0033] One aspect of the present invention can be a semiconductive resin composition including a base resin in which two types of ethylene butyl acrylate resins having melt indices satisfying the following formulas 1 and 2 are mixed, carbon black, an antioxidant, and a crosslinking agent.

[0034]

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[0035] By mixing a first ethylene butyl acrylate resin having a melting index value in the MI1 range with a second ethylene butyl acrylate resin having a melting index value in the MI2 range to form the base resin contained in the semiconductive composition, the processability of the semiconductive composition is improved and the miscibility between the compositions is also excellent. Furthermore, it has been discovered that, for reasons that are unclear, semiconductive compositions containing the base resin have a significantly lower volume resistivity than resins containing a single ethylene butyl acrylate and two different polymer resins.

[0036] The effect of reducing the volume resistivity is a heterogeneous effect that occurs by mixing the first ethylene butyl acrylate resin and the second ethylene butyl acrylate resin that satisfy the formulas 1 and 2 without adding any additional conductive material, and the volume resistivity can be reduced without deteriorating the processability and mechanical properties inherent to the semiconductive composition.

[0037] According to one embodiment of the present invention, the MI1 value and MI2 value of the base resin satisfy the following formula 3, thereby further reducing the volume resistivity at high temperatures.

[0038]

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[0039] When the difference between the MI1 and MI2 values ​​of the first ethylene butyl acrylate resin and the second ethylene butyl acrylate resin satisfies the above range, it can be confirmed that the volume resistivity at high temperatures is further reduced.

[0040] The semiconductive layer has a low volume resistivity at high temperatures, which can prevent the semiconductive layer from being broken down, and ultimately has the effect of preventing the shortening of the cable's lifespan.

[0041] According to one embodiment of the present invention, when the base resin satisfies the MI1 value of 5 to 10 g / 10 min and the MI2 value of 15 to 25 g / 10 min and the formula 3, the volume resistivity can be further reduced.

[0042] According to another aspect of the present invention, when the first ethylene butyl acrylate resin in the base resin is an ethylene butyl acrylate copolymer having a content of structural units derived from butyl acrylate monomers of 15 to 18 mol% and a melt index of 5 to 10 g / 10 min, and the second ethylene butyl acrylate resin is an ethylene butyl acrylate copolymer having a content of structural units derived from butyl acrylate monomers of 19 to 22 mol% and a melt index of 17 to 22 g / 10 min, a semiconductive composition having the lowest volume resistance at high temperatures can be provided.

[0043] By including an antioxidant, the semiconductive composition can maintain excellent volume resistivity, processability, and mechanical strength at high temperatures, while suppressing deterioration of the semiconductive composition for a long period after processing.

[0044] The antioxidant according to one aspect of the present invention may be at least one selected from a phenol-based compound and a thioether-based compound.

[0045] Specifically, the phenolic compounds include 2,2'-thiodiethylene-bis-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, 4,4'-thio-bis-(2-t-butyl-5-methylphenol), 1,2-dihydro-2,2,4-trimethylquinoline, diethyl((3,5-bis-(1,1-dimethylethyl)-4-hydroxyphenyl)methyl)phosphonate, 1,3,4-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzene)-1,3,5-triazine-2,4,6-(1 The hydroxybenzoates may include, but are not limited to, one or more selected from the group consisting of N,N'-bis-(3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionyl)hydrazine, N,N'-bis-(2,4-di-tert-butyl-4'-hydroxyphenyl)propionyl)-trione, tetrakis[methylene-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]methane, octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, tris(2,4-di-tert-butylphenyl)phosphite, and N,N'-bis-(3-(3',5'-di-t-butyl-4'-hydroxyphenyl)propionyl)hydrazine.

[0046] In addition, the thioether compound may include at least one selected from the group consisting of dilauryl thiodipropionate, ditridecyl thiodipropionate, dimyristyl thiodipropionate, dioctadecyl disulfide, bis[2-methyl-4-(3-n-dodecylthiopropionyloxy)-5-tert-butylphenyl]sulfide, pentaerythritol-tetrakis-(3-laurylthiopropionate), 1,4-cyclohexanedimethanol, 3,3'-thiobispropanoic acid dimethyl ester polymer, and distearyl thiodipropionate, but is not limited thereto.

[0047] By using the antioxidant, when the semiconductive resin composition is processed, not only the processability of the polymer is increased but also oxidation of the polymer can be prevented.

[0048] The semiconductive composition is crosslinked using a crosslinking agent. One suitable method is to impregnate a polymer powder or polymer pellets with the crosslinking agent. The mixture is then heated to a temperature above the decomposition temperature of the crosslinking agent. Suitable crosslinking agents that can be used include, for example, di(tert-butylperoxyisopropyl)benzene, 1,1-(tert-butylperoxy)-3,3,5-trimethylcyclohexane, normal-butyl-4,4-(bis-butylperoxy)valerate, dicumyl peroxide, perflutyl peroxide, 1,1-bis(tert-butylperoxy)-diisopropylbenzene, benzoyl peroxide, 2,5-dimethyl-2,5-di-tert-butylperoxyhexane, tert-butylperoxybenzoic acid, di-tert-butyl peroxide, and 2,5-dimethyl-2,5-di-tert-butylperoxylhexane, preferably perflutyl peroxide, 1,1-(tert-butylperoxy)-3,3,5-trimethylcyclohexane, benzoyl peroxide, and dicumyl peroxide, more preferably dicumyl peroxide and perflutyl peroxide, but are not limited to these.

[0049] According to one embodiment of the present invention, the composition may contain 30 to 100 parts by weight of carbon black, 0.01 to 5 parts by weight of antioxidant, and 0.1 to 10 parts by weight of crosslinker per 100 parts by weight of the base resin, preferably 40 to 90 parts by weight of carbon black, 0.1 to 3 parts by weight of antioxidant, and 0.3 to 5 parts by weight of crosslinker per 100 parts by weight of the base resin, and more preferably 55 to 60 parts by weight of carbon black, 0.2 to 1 part by weight of antioxidant, and 0.5 to 3 parts by weight of crosslinker per 100 parts by weight of the base resin, but is not limited to this.

[0050] When the composition content of the semiconductive composition satisfies the above range, the crosslinking time and degree are appropriate, and the semiconductive composition has excellent processability and mechanical strength, does not deteriorate even after long-term use, and has excellent volume resistance.

[0051] Furthermore, according to one aspect of the present invention, the semiconductive composition may contain a metal stearate compound or the like. Specifically, the semiconductive composition may contain zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, or the like. Preferably, the semiconductive composition may contain calcium stearate and zinc stearate, and more preferably, the semiconductive composition may contain zinc stearate, but is not limited to these.

[0052] The inclusion of the metal stearate can minimize the slapping phenomenon of polymers. The semiconductive layer of the present invention manufactured using the metal stearate can have excellent surface properties without forming protrusions on the surface. In addition, the metal stearate can improve the fluidity of the electrically conductive resin composition, thereby minimizing deviations in electrical conductivity due to stretching when molding the electrically conductive resin composition.

[0053] The semiconductive resin composition may further include a processing aid, which may include montan wax, fatty acid ester, triglyceride or partial ester thereof, glycerin ester, polyethylene wax, paraffin wax, metal soap-based lubricant, amide-based lubricant, etc., and preferably includes, but is not limited to, fatty acid ester, triglyceride or partial ester thereof, and polyethylene wax.

[0054] By further including the processing aid, the releasability of the composition from the conductor can be improved and the extrusion load can be reduced.

[0055] The semiconductive resin composition according to one aspect of the present invention can be crosslinked to produce a cured semiconductive resin. The cured crosslinked semiconductive resin has excellent processability and mechanical strength, and excellent volume resistivity even at high temperatures, making it suitable for use in the semiconductive layer of an extra-high voltage cable wire.

[0056] The degree of crosslinking of the cured semiconductive resin may affect factors such as mechanical properties and volume resistance, and the degree of crosslinking can be determined by the crosslink density.

[0057] The crosslinked cured semiconductive resin may have a crosslink density of 15 dNm or more, preferably 16 to 20 dNm, and more preferably 17 to 18 dNm, as measured by a moving die rheometer (MDR), but is not limited thereto.

[0058] When the crosslinking degree satisfies the above crosslink density range, excellent mechanical properties can be achieved, and at the same time, excellent processability can also be achieved.

[0059] According to one aspect of the present invention, the semiconductive resin cured product may have a volume resistivity at 90°C according to ASTM D991 of 170 Ω·cm or less, preferably 150 Ω·cm or less, and more preferably 100 Ω·cm or less.

[0060] Furthermore, the volume resistivity of the cured semiconductive resin according to ASTM D991 at 135°C may be 150 Ω cm or less, preferably 140 Ω cm or less, and more preferably 130 Ω cm or less, but is not limited thereto.

[0061] Next, a method for producing the semiconductive composition will be described.

[0062] According to one aspect of the present invention, a) adding the base resin, carbon black, and antioxidant of paragraph 1 to a first mixer and then mixing them to prepare a composite resin; b) manufacturing the composite resin in the form of a composite resin chip; c) adding the composite resin chips and the crosslinking agent to a second mixer and mixing them to prepare a semiconductive resin composition; d) crosslinking and aging the semiconductive resin composition to provide a cured semiconductive resin, thereby producing a semiconductive composition.

[0063] The temperature of the first mixer in step a) may be 90 to 120°C, but is not limited thereto as long as it is a commonly used temperature. The first mixer may be a Banbury mixer (dispersion type kneader), but is not limited thereto as long as it is a commonly used device.

[0064] In step b), the composite resin kneaded in the first kneader may be prepared in the form of chips, which are easy to process. The chips may be prepared by passing through a roll mill and a crusher, but are not limited thereto as long as they are commonly used devices.

[0065] The size of the chip may be 2 to 10 mm, preferably 3 to 8 mm, but is not limited thereto.

[0066] In step c), the composite resin chips and the crosslinking agent are put into a second kneader and kneaded at 60 to 80° C. and 30 to 60 rpm, but the kneading method is not limited thereto.

[0067] The semiconductive resin composition prepared in step c) may be crosslinked and aged in an oven at a temperature equal to or higher than the curing temperature of the curing agent, specifically, 60 to 100°C, and the crosslinking and aging time may be, but is not limited to, 10 minutes to 12 hours.

[0068] According to one aspect of the present invention, the crosslinking time in step d) is preferably 10 minutes or longer, more preferably 12 minutes or longer. If the crosslinking time is too short, the processing stability of the semiconductive cured product may decrease during cable processing.

[0069] The present invention will be described in more detail below with reference to examples and comparative examples. However, the following examples and comparative examples are merely examples for explaining the present invention in more detail, and the present invention is not limited to the following examples and comparative examples.

[0070] [Tensile strength and elongation] The tensile strength and elongation were measured at 250 mm / min in accordance with ATSM D638.

[0071] [Crosslink density / scorch time] The crosslink density within crosslinked polymer compositions can be determined by analysis on a moving die rheometer (MDR) at 180°C according to ASTM D5289-12. The crosslink density was calculated as the difference between the maximum elastic torque (MH) and the minimum elastic torque (ML). The scorch time (TS1) was calculated from the time it took for the torque to increase by 1 dNm from the minimum torque (ML) measured at 145°C.

[0072] [Volume resistivity] Volume resistivity was measured according to ASTM D991.

[0073] [Melt Index] The melting index is measured at 125°C and 2.16 kg according to the ASTM D1238 measurement method, and the melting index unit is g / 10 min.

[0074] [Example 1] The semiconductive resin composition was prepared by kneading 100 parts by weight of an ethylene butyl acrylate copolymer with a butyl acrylate content of 17 mol% and a melt index of 7.0 g / 10 min, 100 parts by weight of an ethylene butyl acrylate copolymer with a butyl acrylate content of 20 mol% and a melt index of 20.0 g / 10 min, 0.95 parts by weight of 1,2-dihydro-2,2,4-trimethylquinoline (Naugard SuperQ, Mihara Shoji), and 113 parts by weight of carbon black (VXC500) in a Banbury mixer at 150°C for 30 minutes. The mixture was passed through a roll mill and crusher to produce chips, and then 2.8 parts by weight of a crosslinking agent (di(tert-butylperoxyisopropyl)benzene (AkzoNobel)) was added in a Brabender mixer. The mixture was impregnated at 75°C for 10 minutes at 40 rpm and then aged in an oven at 70°C for 8 hours to produce a semiconductive resin composition.

[0075] The tensile strength, elongation, scorch time and crosslink density of the prepared semiconductive resin composition were measured and are shown in Table 1, and the volume resistivity was measured and is shown in Table 2.

[0076] [Example 2] The same procedure was carried out as in Example 1, except that the amount of carbon black was changed to 107 parts by weight. The tensile strength, elongation, scorch time, and crosslink density of the prepared semiconductive resin composition were measured and the results are shown in Table 1, and the volume resistivity was measured and the results are shown in Table 2.

[0077] [Example 3] The same procedure was repeated as in Example 1, except that an ethylene butyl acrylate copolymer having a butyl acrylate content of 17 mol% and a melt index of 15.0 g / 10 min was used instead of the ethylene butyl acrylate copolymer having a butyl acrylate content of 17 mol% and a melt index of 7.0 g / 10 min. The tensile strength, elongation, scorch time, and crosslink density of the prepared semiconductive resin composition were measured and the results are listed in Table 1, and the volume resistivity was measured and the results are listed in Table 2.

[0078] [Example 4] The same procedure was carried out as in Example 1, except that an ethylene-butyl acrylate copolymer having a butyl acrylate content of 20 mol % and a melt index of 9.0 g / 10 min was used instead of an ethylene-butyl acrylate copolymer having a butyl acrylate content of 17 mol % and a melt index of 7.0 g / 10 min.

[0079] [Example 5] The same procedure as in Example 1 was carried out, except that 1.5 parts by weight of zinc stearate was further added to 100 parts by weight of ethylene butyl acrylate copolymer having a butyl acrylate content of 17 mol % and a melt index of 7.0 g / 10 min.

[0080] [Comparative Example 1] The semiconductive resin composition was prepared by kneading in a Banbury mixer at 150°C for 30 minutes. 100 parts by weight of ethylene butyl acrylate copolymer with a butyl acrylate content of 17 mol% and a melt index of 7.0 g / 10 min was mixed with 0.90 parts by weight of 1,2-dihydro-2,2,4-trimethylquinoline (Naugard SuperQ, Miwon Corporation) and 56.7 parts by weight of carbon black (VXC500) at 100°C for 30 minutes. The mixture was passed through a roll mill and crusher to form chips, and then 1.4 parts by weight of a crosslinker (di[tert-butylperoxyisopropyl]benzene (AkzoNobel)) was added in a Brabender mixer. The mixture was impregnated at 75°C for 10 minutes at 40 rpm and then aged in a 70°C oven for 8 hours to prepare the semiconductive resin composition.

[0081] The tensile strength, elongation, scorch time and crosslink density of the prepared semiconductive resin composition were measured and are shown in Table 1, and the volume resistivity was measured and is shown in Table 2.

[0082] [Table 1]

[0083] [Table 2]

[0084] As described above, the present invention has been described using specific matters and limited examples and drawings, but these are provided to help a more comprehensive understanding of the present invention, and the present invention is not limited to the above examples. Those skilled in the art will appreciate that various modifications and variations can be made from these descriptions.

[0085] Therefore, the concept of the present invention is not limited to the described embodiments, and all aspects that fall within the scope of the claims described below, as well as equivalent or similar variations to the claims, can be said to fall within the scope of the concept of the present invention.

Claims

1. A semiconductive resin composition comprising a base resin in which ethylene butyl acrylates having different melt indices are mixed, carbon black, an antioxidant, and a peroxide crosslinking agent, the base resin is a mixture of a first ethylene butyl acrylate resin and a second ethylene butyl acrylate resin in equal amounts; The first ethylene butyl acrylate resin is an ethylene butyl acrylate copolymer having a content of structural units derived from butyl acrylate monomer of 15 to 18 mol% and a melt index of 5 to 10 g / 10 min measured under conditions of 125°C and 2.16 kg according to ASTM D1238; The second ethylene butyl acrylate resin is an ethylene butyl acrylate copolymer having a content of structural units derived from butyl acrylate monomer of 19 to 22 mol% and a melt index of 17 to 22 g / 10 min measured under conditions of 125°C and 2.16 kg according to ASTM D1238; the peroxide crosslinking agent has a decomposition temperature lower than a crosslinking temperature applied when crosslinking the semiconductive resin composition, A semiconductive resin composition comprising 55 to 60 parts by weight of carbon black, 0.2 to 1 part by weight of an antioxidant, and 0.5 to 3 parts by weight of a peroxide crosslinking agent, relative to 100 parts by weight of the base resin.

2. 2. The semiconductive resin composition according to claim 1, wherein the antioxidant is at least one selected from the group consisting of phenolic compounds and thioether compounds.

3. The semiconductive resin composition according to claim 1 , further comprising a metal stearate.

4. 4. The semiconductive resin composition according to claim 3, wherein the metal stearates include zinc stearate, calcium stearate, aluminum stearate, and magnesium stearate.

5. A cured semiconductive resin obtained by crosslinking the semiconductive resin composition according to any one of claims 1 to 4.

6. The cured semiconductive resin according to claim 5, wherein the cured semiconductive resin has a crosslink density of 16 to 20 dNm as measured by a moving die rheometer (MDR).

7. a) adding a base resin, carbon black, and an antioxidant to a first kneader and then kneading them to produce a composite resin; b) manufacturing the composite resin in the form of a composite resin chip; c) adding the composite resin chips and the peroxide crosslinking agent into a second kneader and mixing them to prepare a semiconductive resin composition; d) crosslinking and aging the semiconductive resin composition to provide a cured semiconductive resin, the base resin is a mixture of a first ethylene butyl acrylate resin and a second ethylene butyl acrylate resin in equal amounts; The first ethylene butyl acrylate resin is an ethylene butyl acrylate copolymer having a content of structural units derived from butyl acrylate monomer of 15 to 18 mol% and a melt index of 5 to 10 g / 10 min measured under conditions of 125°C and 2.16 kg according to ASTM D1238; The second ethylene butyl acrylate resin is an ethylene butyl acrylate copolymer having a content of structural units derived from butyl acrylate monomer of 19 to 22 mol% and a melt index of 17 to 22 g / 10 min measured under conditions of 125°C and 2.16 kg according to ASTM D1238; the peroxide crosslinking agent has a decomposition temperature lower than a crosslinking temperature applied when crosslinking the semiconductive resin composition, A method for producing a cured semiconductive resin product, comprising, per 100 parts by weight of the base resin, 55 to 60 parts by weight of carbon black, 0.2 to 1 part by weight of an antioxidant, and 0.5 to 3 parts by weight of a peroxide crosslinking agent.

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