KR102351547B1 - Halogen-free insulating composition with excellent oil resistance and low-teperature resistance and cable having a dielectric layer formed from the same - Google Patents

Abstract

The present invention relates to a non-halogen-based insulating composition having excellent oil resistance and cold resistance, and an electric wire comprising an insulating layer formed therefrom. Specifically, the present invention provides an insulating composition that has excellent oil resistance, chemical resistance, cold resistance, insulation, etc., which are difficult to secure at the same time, and is excellent in flame retardancy and environment-friendly despite the use of a non-halogen flame retardant, and furthermore excellent processability, and It relates to a wire comprising an insulating layer formed from.

Description

Halogen-free insulating composition with excellent oil resistance and low-teperature resistance and cable having a dielectric layer formed from the same

The present invention relates to a non-halogen-based insulating composition having excellent oil resistance and cold resistance, and an electric wire comprising an insulating layer formed therefrom. Specifically, the present invention provides an insulating composition that has excellent oil resistance, chemical resistance, cold resistance, insulation, etc., which are difficult to secure at the same time, and is excellent in flame retardancy and environment-friendly despite the use of a non-halogen flame retardant, and furthermore excellent processability, and It relates to a wire comprising an insulating layer formed from.

Electric wires used in railway vehicles, ships, automobiles, etc. are required to have oil resistance, chemical resistance, chemical resistance, cold resistance, etc. at the same time depending on their usage environment.

Conventional electric wires for railway vehicles use ethylene vinyl acetate (EVA) resin or the like to form an insulating layer thereof. The ethylene vinyl acetate (EVA) resin has excellent oil resistance and chemical resistance because the molecule contains a polar group that repels oil components, lipophilic compounds, etc. have it

Therefore, in the ethylene vinyl acetate (EVA) resin, nitrile-butadiene rubber There is an example of applying the same, but in this case, while cold resistance and insulation are somewhat improved, there is a problem that oil resistance is greatly reduced.

In addition, it may be considered to apply an engineering plastic resin such as expensive polyester or high-density polyethylene resin that simultaneously satisfies oil resistance, chemical resistance, cold resistance, insulation, etc. When chemical crosslinking using a low-temperature crosslinking agent is performed, not only early crosslinking may occur before the resin is molded, but also these resins have very high hardness and stiffness, resulting in greatly reduced flexibility and cold resistance. There is a problem in that workability such as performance and constructability is greatly reduced, and it is difficult to apply it to a wire used in a low-temperature environment, for example, -50°C.

On the other hand, a flame retardant is added to the insulating composition forming the insulating layer of the electric wire in order to secure the flame retardancy of the conventional electric wire for railroad vehicles. There is a problem in that environmental pollution is caused, such as toxic gas being generated when incinerated for disposal of electric wires.

Therefore, a new composition for forming an insulation layer of an electric wire for railroad vehicles with excellent oil resistance, chemical resistance, cold resistance, insulation, etc., which was difficult to simultaneously secure in the prior art, and sufficient flame retardancy, eco-friendly and processability, and an insulation layer formed therefrom There is an urgent need for an electric wire that includes it.

An object of the present invention is to provide an insulating composition having excellent oil resistance, chemical resistance, cold resistance, insulation, etc. at the same time, and an electric wire including an insulating layer formed therefrom.

Another object of the present invention is to provide an environmentally friendly insulating composition having sufficient flame retardancy and an electric wire including an insulating layer formed therefrom.

Furthermore, an object of the present invention is to provide an insulating composition having excellent workability and workability while reducing manufacturing cost, and an electric wire including an insulating layer formed therefrom.

In order to solve the above problems, the present invention,

As an insulating composition, as a base resin, an olefin-based resin having a melting point (Tm) of 80 to 110°C and a glass transition temperature (Tg) of -60 to -20°C, and a rubber having a glass transition temperature (Tg) of -60 to -30°C Based on 100 parts by weight of the resin and the base resin, an insulating specimen comprising 70 to 200 parts by weight of a non-halogen-based flame retardant, and prepared by crosslinking the insulating composition, was subjected to standard IEC 60811-2-1 at 70° C. for 168 hours. Provided is an insulation composition, wherein the residual tensile strength and residual elongation measured after immersion in the specified IRM 903 oil are 60 to 140% of the initial tensile strength and initial elongation before immersion in the oil.

Here, according to KS C 3004, five insulation specimens prepared by crosslinking of the insulation composition were prepared with a thickness of 2.0±0.2 mm, a width of 6.0±0.4 mm, and a length of 38.0±2 mm, at -50°C for 2 minutes and 30 minutes. It provides an insulating composition, characterized in that all of the five insulating specimens are not cut and separated when struck after being immersed in an ethyl alcohol solution for seconds.

In addition, the olefin-based resin has a melt viscosity of 1 to 5 g/10min when measured by applying a load of 2.16 kg at 190° C., a Shore A hardness of 70 to 95, a coefficient of friction of 0.1 to 0.2, and an elastic modulus of 300 to It provides an insulating composition, characterized in that 1,000 kgf / ㎠.

And, the olefin-based resin provides an insulating composition, characterized in that the ethylene alpha olefin elastomer resin.

Furthermore, the rubber resin provides an insulating composition, characterized in that the Mooney viscosity is 30 to 50.

Here, the rubber resin provides an insulating composition, characterized in that the ethylene-propylene-diene-based rubber resin.

On the other hand, based on 100 parts by weight of the base resin, it provides an insulating composition comprising 40 to 70 parts by weight of the olefin-based resin and 30 to 60 parts by weight of the rubber resin.

And, the flame retardant provides an insulating composition comprising magnesium hydroxide (Mg(OH) ₂ ), aluminum hydroxide (Al(OH) ₃ ), or both.

In addition, magnesium hydroxide (Mg(OH) ₂ ), aluminum hydroxide (Al(OH) ₃ ), or both, are surface-modified with vinylsilane, stearic acid, oleic acid or aminopolysiloxane, have a Mohs hardness of 2-3, and particles It provides an insulating composition, characterized in that the size is 0.7 to 6 ㎛.

On the other hand, based on 100 parts by weight of the base resin, it provides an insulating composition, characterized in that it further comprises 2 to 6 parts by weight of an organic peroxide-based crosslinking agent having a thermal decomposition initiation temperature of 110 to 180 ℃.

Furthermore, it provides an insulating composition, characterized in that it further comprises a compounding oil, a flame retardant aid, a crosslinking aid, an antioxidant, a lubricant, or a combination thereof.

and a conductor; And surrounding the conductor, it provides a wire comprising an insulating layer formed from the insulating composition of claim 1 or claim 2 .

Also, conductor; an insulating inner layer surrounding the conductor and formed from a rubber resin; And enclosing the insulating inner layer and comprising an insulating outer layer formed from the insulating composition of claim 1 or 2, it provides an electric wire.

Here, it provides an electric wire, characterized in that it further comprises a tape layer formed by winding a nylon or polyethylene terephthalate tape between the conductor and the insulating layer.

The non-halogen-based insulating composition having excellent oil resistance and cold resistance according to the present invention has oil resistance, chemical resistance, and cold resistance by precisely controlling the melting point (Tm) and/or glass transition temperature (Tg) of a specific olefin-based resin and rubber resin as a base resin. , insulation, and the like can be simultaneously improved.

In addition, the non-halogen-based insulating composition having excellent oil resistance and cold resistance according to the present invention exhibits sufficient flame retardancy and excellent environmental friendliness despite the use of a non-halogen-based flame retardant.

Furthermore, the non-halogen-based insulating composition having excellent oil resistance and cold resistance according to the present invention exhibits an excellent effect of improving processability, workability, etc. while reducing manufacturing cost through the formulation of a specific base resin.

1 schematically shows an embodiment of an electric wire formed from a non-halogen-based insulating composition having excellent oil resistance and cold resistance according to the present invention.
2 schematically shows another embodiment of an electric wire formed from a non-halogen-based insulating composition having excellent oil resistance and cold resistance according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content may be thorough and complete, and the spirit of the present invention may be sufficiently conveyed to those skilled in the art. Like reference numerals refer to like elements throughout.

The non-halogen-based insulating composition having excellent oil resistance and cold resistance according to the present invention may include an olefin-based resin and a rubber resin as a base resin.

The olefin-based resin may be a polyolefin resin such as polyethylene or polypropylene, preferably a polyolefin elastomer (POE), more preferably an ethylene alpha olefin-based elastomer resin. Here, the ethylene alpha olefin-based elastomer resin may be a random or block copolymer elastomer of ethylene and an α-olefin such as propylene, 1-butene, 1-pentene, 1-hexene, and 1-octene, or a combination thereof. .

The olefin-based resin may have a melting point (melting temperature; Tm) of 80 to 110°C. When the melting point of the olefin-based resin is high as described above, the intermolecular space constituting the olefin-based resin is narrow even at the operating temperature of the electric wire, so that penetration of an oil component, a lipophilic compound, etc. can be effectively suppressed. This is a method completely different from the method in which ethylene vinyl acetate, which is a conventional oil-resistant resin, exhibits oil resistance by the polar group contained in its molecule, and also it is possible to avoid deterioration in insulation due to the presence of the polar group.

In addition, the olefin-based resin has a low melting point (Tm) compared to engineering plastics having excellent oil resistance, chemical resistance, cold resistance, insulation, etc. Crosslinking is possible.

In summary, if the melting point (Tm) of the olefin-based resin is less than 80 ℃, the oil resistance of the insulating composition may be reduced, whereas if the melting point (Tm) is more than 110 ℃, the hardness of the insulating composition is high, such as cold resistance, flexibility, etc. This may decrease and at the same time, the processing temperature may rise, so that chemical crosslinking by a crosslinking agent having a decomposition initiation temperature lower than the processing temperature may not be possible.

In addition, the olefin-based resin may have a glass transition temperature (Tg) of -60 to -20 ℃. When the glass transition temperature (Tg) of the olefin-based resin is greater than -20°C, the cold resistance of the insulating composition may be greatly reduced, whereas when the glass transition temperature (Tg) is less than -60°C, the mechanical strength of the insulating composition is can be lowered

Furthermore, the olefin-based resin has a melt viscosity of 190° C. and a load of 2.16 kg to secure the mechanical properties of the insulating composition and the workability and constructability of an electric wire including an insulating layer formed from the insulating composition. 1 to 5 g/10min, the Shore A hardness may be 70 to 95, the friction coefficient may be 0.1 to 0.2, and the elastic modulus may be 300 to 1,000 kgf/cm 2 .

The rubber resin is natural rubber, styrene butadiene rubber (SBP), butadiene rubber (BR), chloropyrene rubber (CR), nitrile butadiene rubber (NBR), butyl rubber, ethylene propylene rubber (EPDM), chlorosulfonated polyethylene rubber ( CSM), acrylic rubber, fluororubber, silicone rubber, etc. may include at least one rubber resin selected from the group consisting of, preferably ethylene propylene rubber (EPDM).

The glass transition temperature (Tg) of the rubber resin may be -60 to -30 ℃. When the glass transition temperature (Tg) of the rubber resin is less than -60°C, the mechanical strength of the insulating composition may be reduced, whereas when the glass transition temperature (Tg) is greater than -30°C, the cold resistance of the insulating composition is greatly reduced can be

In addition, the rubber resin may have a Mooney viscosity of 30 to 50. When the Mooney viscosity of the rubber resin is less than 30, the cold resistance and mechanical properties of the insulating composition may be deteriorated, whereas when the Mooney viscosity is more than 50, the flexibility, cold resistance, filler loading property, and mechanical properties of the insulating composition properties and the like may be deteriorated.

Based on 100 parts by weight of the mixed resin of the olefin-based resin and the rubber resin, the content of the olefin-based resin may be 40 to 70 parts by weight, and the content of the rubber resin may be 30 to 60 parts by weight. When the content of the olefin-based resin is less than 40 parts by weight, the oil resistance of the insulating composition may be reduced, whereas when the content of the olefin-based resin is more than 70 parts by weight, the flexibility of the insulating composition is lowered and an insulating layer formed therefrom The workability such as layingability and constructability of the electric wire containing the may be deteriorated.

The insulating composition according to the present invention may further include 3 to 50 parts by weight of a compounding oil, for example, an alkylester-based oil, a paraffinic oil, and the like, based on 100 parts by weight of the base resin. The compounding oil may further improve flexibility, cold resistance, and the like of the insulating composition.

The insulating composition according to the present invention has oil resistance, chemical resistance, cold resistance, which could not be achieved at the same time by controlling the specific resin constituting the base resin, its blending ratio, and the melting point (Tm) and glass transition temperature (Tg) of the resin, It is possible to exhibit an excellent effect of simultaneously improving insulation and the like.

The insulating composition according to the present invention may further include a flame retardant. The flame retardant may include a non-halogen-based flame retardant such as magnesium hydroxide (Mg(OH) ₂ ) and aluminum hydroxide (Al(OH) _{3 ).} Since the flame retardant such as magnesium hydroxide is hydrophilic having high surface energy, while the base resin is hydrophobic having low surface energy, the flame retardant has poor dispersibility to the base resin, and may adversely affect electrical properties. have.

Therefore, in order to solve this problem, the flame retardant such as magnesium oxide is preferably surface-modified with vinylsilane, stearic acid, oleic acid, aminopolysiloxane, or the like. When the flame retardant is surface-modified by vinyl silane, etc., hydrolyzed groups such as vinyl silane are attached by chemical bonding to the surface of flame retardants such as magnesium hydroxide by condensation reaction, and the silane group reacts with the base resin to ensure excellent dispersibility be able to do

The non-halogen-based flame retardant has a Mohs hardness of 2 to 3 and a particle size of 0.7 to 6 μm in order to improve dispersibility in the insulating composition while maintaining its shape and function in the insulating layer extrusion process by the insulating composition. It is preferable to be

The content of the non-halogen-based flame retardant may be 70 to 200 parts by weight based on 100 parts by weight of the base resin. When the content of the non-halogen-based flame retardant is less than 70 parts by weight, the flame retardancy of the insulating composition may be insufficient, whereas when it exceeds 200 parts by weight, physical properties such as cold resistance and insulation of the insulating composition may be deteriorated. The insulating composition according to the present invention may further include 0.5 to 3 parts by weight of a flame retardant auxiliary agent such as red, based on 100 parts by weight of the base resin in addition to the non-halogen-based flame retardant.

The insulating composition according to the present invention may include a crosslinking agent for crosslinking the base resin, and may further include a crosslinking aid. The crosslinking agent is a silane-based crosslinking agent, or dicumyl peroxide, benzoyl peroxide, lauryl peroxide, t-butyl cumyl peroxide, di (t-butyl peroxy isopropyl) benzene, 2, It may be an organic peroxide-based crosslinking agent such as 5-dimethyl-2,5-di(t-butyl peroxy)hexane or di-t-butyl peroxide.

In particular, when the base resin constituting the insulating composition according to the present invention is cross-linked by a chemical cross-linking method using an organic peroxide-based cross-linking agent such as dicumyl peroxide, the thermal decomposition initiation temperature of the organic peroxide-based cross-linking agent is preferably 110 to 180 ° C. do. When the organic peroxide-based crosslinking agent has the thermal decomposition initiation temperature as described above, it is not decomposed during extrusion molding of the insulating composition, thereby securing stable process conditions.

The content of the crosslinking agent may be 2 to 6 parts by weight based on 100 parts by weight of the base resin. When the content of the crosslinking agent is less than 2 parts by weight, the degree of crosslinking of the base resin may decrease, and the oil resistance and room temperature strength of the insulating composition may be lowered, whereas if the content of the crosslinking agent is more than 6 parts by weight, the insulating composition is a side reaction through excessive crosslinking. The elongation rate, cold resistance, etc. of the composition may be reduced, and premature crosslinking may occur.

In addition, the crosslinking aid is from the group consisting of triallyisocyanurate, triallycyanurate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, and the like. One or more selected crosslinking aids may be included.

The crosslinking aid may decrease the content of the crosslinking agent by increasing the activity of the crosslinking agent to increase the degree of crosslinking. The content of the crosslinking aid may be 1.5 to 3 parts by weight based on 100 parts by weight of the base resin.

The insulating composition according to the present invention may further include other additives such as antioxidants and lubricants. In particular, the antioxidant may include antioxidants such as phenol-based and amine-based antioxidants, and the content of the antioxidant may be 0.5 to 4 parts by weight based on 100 parts by weight of the base resin.

The present invention relates to an electric wire comprising an insulating layer formed by the above-described insulating composition. 1 schematically shows an embodiment of an electric wire formed from a non-halogen-based insulating composition having excellent oil resistance and cold resistance according to the present invention.

As shown in FIG. 1 , the electric wire according to the present invention may include a conductor 10 and an insulating layer 20 surrounding the conductor 10 . Here, the conductor 10 may be made of a conductive metal such as copper or aluminum, preferably copper. The conductor 10 may be a single wire or a stranded wire obtained by twisting a plurality of single wires. In addition, the insulating layer 20 may be formed of the non-halogen-based insulating composition having excellent oil resistance and cold resistance according to the present invention described above.

2 schematically shows another embodiment of an electric wire formed from a non-halogen-based insulating composition having excellent oil resistance and cold resistance according to the present invention. 2, in the electric wire according to the present invention, in order to further improve the cold resistance of the electric wire, the insulating layer 20 includes the insulating inner layer 21 including a rubber resin and the present invention described above. It may include an insulating outer layer 22 formed from the insulating composition according to the

In addition, in the electric wire according to the present invention, a tape layer is added between the conductor 10 and the insulating layer 20 in order to prevent the insulating composition from penetrating into the conductor 10 in the extrusion process of the insulating layer 20 . can be included as The tape layer may be made of a material such as nylon or polyethylene terephthalate (PET).

[Example]

1. Preparation example

Insulation compositions according to each of Examples and Comparative Examples were prepared by kneading in an open roll with the components and mixing ratios as shown in Table 1 below, and then crosslinked by heating under pressure at 170° C. for 20 minutes to crosslink IEC 60811-1-1 Insulation specimens were prepared according to

Example comparative example One 2 3 One 2 3 4 5 6 crosslinking method chemical crosslinking research bridge chemical crosslinking resin 1 70 50 40 20 50 50 50 resin 2 50 resin 3 50 resin 4 30 50 60 50 50 80 50 50 resin 5 50 flame retardant 130 130 130 130 130 130 70 200 130 Oxidation
inhibitor 2 2 2 2 2 2 2 2 2 crosslinking agent 4 4 4 4 - 4 4 4 4 crosslinking aid 3 3 3 3 3 3 3 3 3 blended oil 6 6 6 6 6 6 6 6 6

Resin 1: Ethylene alpha olefin copolymer (Tm=95°C, Tg=-31°C, MFR=1.2, density=0.903)

Resin 2: Ethylene alpha olefin copolymer (Tm=58°C, Tg=-53°C, MFR=1.1, density=0.870)

Resin 3: Ethylene alpha olefin copolymer (Tm=125°C, MFR=1.0, density=0.92)

Resin 4: Ethylene-propylene-diene rubber (EPDM) (Tg=-50℃)

Resin 5: Ethylene vinyl acetate (EVA) (Tg=-26℃)

Flame retardant: magnesium hydroxide surface-treated with vinyl silane (average particle diameter (D50) < 1.5㎛)

Antioxidant: Phenolic antioxidant

Crosslinking agent: dicumyl peroxide

Crosslinking aid: trimethylolpropane trimethacrylate (TMPTMA)

Blended oil: Paraffinic oil

2. Physical property evaluation

The following physical properties were evaluated for the insulating specimens according to Examples and Comparative Examples prepared in Preparation Example, and the results are shown in Table 2 below.

1) Room temperature tensile strength and elongation rate evaluation

Room temperature tensile strength and elongation were evaluated for each insulation specimen in Examples and Comparative Examples at a speed of 250 mm/min in accordance with IEC 60811-1-1.

2) Oil resistance evaluation

For IRM 903 oil specified in IEC 60811-2-1, the tensile strength and elongation were measured after immersing the insulation specimens according to each of Examples and Comparative Examples at 70°C for 168 hours. Oil resistance was evaluated through the degree of change in tensile strength and elongation rate by describing the same time as 100%.

3) Cold resistance evaluation

According to KS C 3004, prepare 5 insulation specimens according to each of Examples and Comparative Examples with a thickness of 2.0±0.2 mm, a width of 6.0±0.4 mm, and a length of 38.0±2 mm, and Cold resistance was evaluated through a cold-resistant hitting test that was immersed in an alcohol solution and then struck. Splitting more than one is called destruction, and cracks or cracks are not called destruction. The evaluation results are displayed in the 0/0/0 format, and the number of specimens with surface cracks/internal cracks/cut separation among the five specimens is indicated.

4) Insulation evaluation

Insulation was evaluated by measuring the volume resistance of each insulating specimen in Examples and Comparative Examples in accordance with the standard IEC 60811.

5) Flame retardant evaluation

In accordance with the standards IEC 60332-1-2 and EN 50305, the flame retardancy was evaluated by measuring the oxygen index for each insulating specimen in Examples and Comparative Examples.

Example comparative example One 2 3 One 2 3 4 5 6 room temperature
Properties Tensile strength (MPa) 16.46 15.52 14.68 13.61 18.11 12.61 16.23 13.52 14.63 Elongation (%) 248.9 251.7 276.4 271.1 378.9 301.7 281.7 171.7 260.7 oil resistance Tensile residual rate (%) 86.7 81.61 82.31 80.64 89.23 76.64 75.61 88.2 89.9 Kidney Residual Rate (%) 91.7 81.37 67.2 55.4 93.71 42.7 77.3 82.1 96.8 Hardness Shore A 96.9 95.9 94.9 92.7 98.9 92.5 90.9 98 95.8 cold resistance Cold-resistant blow (-50℃) 4/1/0 1/0/0 0/0/0 1/0/0 1/2/0 0/0/0 0/0/0 0/0/5 0/0/5 insulation Volume resistance (Ωcm) 2.1×
10 ¹⁵ 2.14×10 ¹⁵ 2.02×10 ¹⁵ 1.2×
10 ¹⁵ 1.52×10 ¹⁵ 2.3×
10 ¹⁵ 2.4×
10 ¹⁵ 8.4×
10 ¹⁵ 1.2×
10 ¹⁴ flame retardant Oxygen Index (%) 32 31.5 31 32 33.5 31 27.5 38.5 34

As shown in Table 2, the insulating specimen according to Comparative Example 1 had a low melting point (Tm) of the olefin-based resin among the base resins, so the tensile strength at room temperature was low, and the oil resistance was greatly reduced when immersed at 70° C., whereas Comparative Example 2 In the insulation specimen according to , since the melting point (Tm) of the olefin-based resin among the base resins was high, the flexibility was reduced due to excessive hardness, and chemical crosslinking was impossible, so crosslinking had to be performed by irradiation crosslinking.

In addition, it was confirmed that the insulation specimen according to Comparative Example 3 had a low content of an olefin-based resin and a high content of a rubber resin in the base resin, so that the tensile strength at room temperature was low and the oil resistance was significantly reduced.

And, the insulation specimen according to Comparative Example 4 had a low content of the flame retardant, so that the flame retardancy was greatly reduced, whereas the insulation specimen according to Comparative Example 5 had a high content of the flame retardant, so that the tensile strength and elongation at room temperature were reduced, and the hardness was high, so flexibility and cold resistance were It was confirmed that the insulation was also deteriorated.

Furthermore, it was confirmed that the insulating specimen according to Comparative Example 6 had a high glass transition temperature (Tg) of the rubber resin, and thus cold resistance was lowered.

Although the above has been described with reference to the preferred embodiment of the present invention, those skilled in the art can variously modify and change the present invention within the scope without departing from the spirit and scope of the present invention described in the claims described below. You can do it. Therefore, if the modified implementation basically includes the elements of the claims of the present invention, all should be considered to be included in the technical scope of the present invention.

10: conductor 20: insulating layer
30: tape layer

Claims (14)

An insulating composition comprising:
As a base resin, ethylene having a melting point (Tm) of 80 to 110°C, a glass transition temperature (Tg) of -60 to -20°C, and a melt viscosity of 1 to 5 g/10min when measured by applying a load of 2.16 kg at 190°C Alpha olefin elastomer resin and ethylene-propylene-diene-based rubber resin having a glass transition temperature (Tg) of -60 to -30°C, and
Based on 100 parts by weight of the base resin, it contains 70 to 200 parts by weight of a non-halogen-based flame retardant,
After immersing an insulation specimen prepared by crosslinking of the insulation composition in IRM 903 oil specified in IEC 60811-2-1 at 70° C. for 168 hours, the residual tensile and elongation percentages measured before immersion in the oil are the initial tensile 60 to 140% of strength and initial elongation. According to claim 1,
According to KS C 3004, five insulation specimens prepared by crosslinking of the insulation composition were prepared with a thickness of 2.0±0.2 mm, a width of 6.0±0.4 mm, and a length of 38.0±2 mm, and at -50°C for 2 minutes and 30 seconds. Insulation composition, characterized in that all of the five insulation specimens are not cut and separated when struck after being immersed in an ethyl alcohol solution. 3. The method of claim 1 or 2,
The ethylene alpha olefin elastomer resin has a Shore A hardness of 70 to 95, a friction coefficient of 0.1 to 0.2, and an elastic modulus of 300 to 1,000 kgf/cm 2 . delete 3. The method of claim 1 or 2,
The ethylene-propylene-diene-based rubber resin has a Mooney viscosity of 30 to 50, the insulation composition. delete 3. The method of claim 1 or 2,
Based on 100 parts by weight of the base resin, 40 to 70 parts by weight of the ethylene alpha olefin elastomer resin and 30 to 60 parts by weight of the ethylene-propylene-diene-based rubber resin, the insulation composition. 3. The method of claim 1 or 2,
The flame retardant comprises magnesium hydroxide (Mg(OH) ₂ ), aluminum hydroxide (Al(OH) ₃ ), or both, the insulation composition. 9. The method of claim 8,
Magnesium hydroxide (Mg(OH) ₂ ), aluminum hydroxide (Al(OH) ₃ ), or both, are surface-modified with vinylsilane, stearic acid, oleic acid or aminopolysiloxane, have a Mohs hardness of 2-3, and a particle size 0.7 to 6 μm, characterized in that the insulating composition. 3. The method of claim 1 or 2,
Based on 100 parts by weight of the base resin, the insulating composition further comprises 2 to 6 parts by weight of an organic peroxide-based crosslinking agent having a thermal decomposition initiation temperature of 110 to 180°C. 3. The method of claim 1 or 2,
Insulation composition, characterized in that it further comprises a compounding oil, a flame retardant aid, a crosslinking aid, an antioxidant, a lubricant, or a combination thereof. conductor; and
An electric wire surrounding the conductor and comprising an insulating layer formed from the insulating composition of claim 1 or 2. conductor;
an insulating inner layer surrounding the conductor and formed from a rubber resin; and
An electric wire surrounding the insulating inner layer and comprising an insulating outer layer formed from the insulating composition of claim 1 or 2 . 14. The method of claim 13,
The electric wire, characterized in that it further comprises a tape layer formed by winding a nylon or polyethylene terephthalate tape between the conductor and the insulating inner layer.

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