JP2003257255A - Flame retardant insulating cable - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flame retardant insulating cable for lead wire that uses a flame retardant resin composite containing no halogen element as an insulating covering material and that has passed the 60 degree inclined combustion test of JIS standard C3005 and is superior in mechanical property such as tensile breaking strength, tensile breaking elongation, and hardness (Shore D), and is superior in heat deformation and lead wire work performance. <P>SOLUTION: This is a flame retardant insulating cable that has extrusion covered on a conductor an olefin system flame retardant resin composite in which a metal hydrate 100-250 parts weight is mixed in 100 parts weight of an olefin system thermoplastic elastomer that is a polymer alloy of polypropylene and ethylenepropylenediene copolymer or a mixture made mainly of this. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention does not generate a harmful gas such as a halogen gas at the time of combustion, and has a flame retardance that passes the JIS standard C3005 60-degree inclined combustion test, good heat deformability, and excellent mechanical properties. The present invention relates to a flame-retardant insulated wire that has characteristics and is mainly used as a lead wire.

[0002]

2. Description of the Related Art Since this type of insulated wire used as a lead wire is used in a switchboard or around a motor such as a generator or a drive, it has high heat resistance and is easy to handle and lead. Therefore, low density polyethylene or linear low density polyethylene is used as the base resin, and a halogen-based flame retardant is added for the purpose of imparting flame retardancy thereto. The halogen-based flame retardant can achieve its purpose even if added in a small amount, but in recent years, there is a demand for a non-halogen flame-retardant resin composition that does not generate harmful halogen gas during combustion because of environmental problems. As such a halogen-free flame-retardant polyolefin-based resin composition, a composition in which a large amount of magnesium hydroxide or the like is mixed with an olefin-based resin, an ethylene-based copolymer, or a halogen-free rubber-based material is known. Although it is used as a coating material for various molded products and electric wires / cables, however, since such a flame-retardant polyolefin resin composition contains a large amount of magnesium hydroxide and the like, the obtained flame-retardant resin composition There is a problem as a coating material for a flame-retardant insulated wire, which is required to be particularly flexible because the product becomes too hard.

Therefore, as a proposal to improve such a problem, a proposal has been made to improve mechanical properties by blending an olefin resin with a styrene elastomer.
However, even such a resin composition is still insufficient as an insulated wire for a lead wire in terms of flexibility (flexibility), and with regard to flame retardancy, the amount of magnesium hydroxide added is reduced. In order to achieve this, a phosphorus-based flame retardant is used in combination, but phosphorus must be added to the minimum necessary amount due to recent environmental problems, and it is satisfactory if high flame retardancy is obtained. Was not.

[0004]

Therefore, the problem to be solved by the present invention is to provide a flame-retardant insulated wire for a lead wire, which uses a flame-retardant resin composition containing no halogen element as an insulating coating material. And its flame resistance is JIS standard C
It passes the 60 degree inclined combustion test of 3005,
As mechanical properties, tensile breaking strength is 10 MPa or more, tensile breaking elongation is 300% or more, hardness (Shore D)
Is 50 or less, and the heat deformation rate of JIS C3005 is 40% or less, and it is to provide a flame-retardant insulated wire excellent in the workability of ejection.

[0005]

In order to solve the above problems, as described in claim 1, an olefin which is a polymer alloy of polypropylene having an amount of 20% or more and an ethylene propylene diene copolymer. The problem can be solved by using a flame-retardant insulated wire in which a conductor is coated with an olefin flame-retardant composition in which 100 to 250 parts by weight of a metal hydrate is mixed with 100 parts by weight of a thermoplastic thermoplastic elastomer.

Further, as described in claim 2, 85 to 55 parts by weight of an olefinic thermoplastic elastomer, 9.5 to 35 parts by weight of ethylene propylene diene copolymer or ethylene propylene rubber modified with maleic acid, and a silanol group-containing compound. 100 to 25 parts by weight of an elastomer mixture consisting of 0.5 to 5 parts by weight of an ethylene propylene diene copolymer grafted with
This can be solved by using 0 part by weight of an olefin flame-retardant composition as a flame-retardant insulated wire coated on a conductor.

Further, as described in claim 3, the olefinic thermoplastic elastomer according to claim 2 is a polymer alloy of polypropylene having an amount of 20% or more and an ethylene propylene diene copolymer. Will be solved by

Further, as described in claim 4, the flame-retardant insulated wire according to any one of claims 1 to 3 has passed the 60-degree inclined combustion test of JIS standard C3005 in flame retardancy. , Tensile strength of 10 MPa or more, elongation of 300
% Or more, hardness (Shore D) is 50 or less, and thermal deformation rate is 4
It is solved by being 0% or less.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.
In the invention described in claim 1, 100 to 250 parts by weight of a metal hydrate is added to 100 parts by weight of an olefin-based thermoplastic elastomer, which is a polymer alloy of polypropylene having a content of 20% or more and an ethylene propylene diene copolymer. The present invention relates to a flame-retardant insulated wire in which a blended olefin-based flame-retardant composition is coated on a conductor, and an olefin-based thermoplastic elastomer used as a base polymer is polypropylene (PP) and ethylene propylene diene copolymer (EPDM). And a polymer alloy of
This olefin-based thermoplastic elastomer is a plastic with excellent impact resistance, but it also has properties as an elastomer, and by using this as a base polymer, a large amount of metal hydrate such as magnesium hydroxide is blended. Also has a feature that mechanical properties are not significantly deteriorated. further,
Since PP having a melting point of 160 ° C. or higher is used, it also has excellent heat resistance. In particular, when the PP is used as a polymer alloy component of 20% or more, the heat deformability becomes excellent. Specifically, a material that passes the heat deformation test of JIS standard C3005 at a temperature of 120 ° C. and a load of 1 kg is obtained, and is suitable as a coating material for a flame-retardant insulated wire used in a high temperature atmosphere like the present invention. Is.

An inorganic metal hydrate is added as a flame retardant to the olefinic thermoplastic elastomer.
This metal hydrate imparts flame retardancy by decomposing upon combustion and releasing water, causing an endothermic reaction and exhibiting a self-extinguishing action. Typical examples of such metal hydrates are magnesium hydroxide, aluminum hydroxide, calcium hydroxide, basic magnesium carbonate, etc. Among them, magnesium hydroxide and aluminum hydroxide are preferably used. Also, in this metal hydrate,
Surface treatment with a fatty acid, a titanate coupling agent or a silane coupling agent is performed. This is to improve the dispersibility and compatibility with the olefinic thermoplastic elastomer serving as the base polymer. The amount of addition is 100 to 250 parts by weight with respect to 100 parts by weight of the thermoplastic elastomer. If the amount of the metal hydrate added is less than 100 parts by weight, the desired high flame retardancy cannot be obtained. That is, JIS standard C300
This is because the 60 degree inclined combustion test of 5 fails. In order to reliably pass the test, it should be 100 parts by weight or more. If the addition amount exceeds 250 parts by weight,
The fluidity of the obtained resin composition decreases, the rigidity of the molded product,
The dimensional stability, impact strength, and the like are reduced, and the coating material of the flame-retardant insulated wire used for the lead wire of the present invention becomes too hard and is not preferable in terms of flexibility. And such an olefin flame-retardant composition is extruded and coated on a conductor such as copper to obtain a flame-retardant insulated wire. The thickness of this extruded coating layer is not particularly limited, but is usually about 1 to 3 mm. The olefin-based flame-retardant composition includes a phosphorus-based compound such as red phosphorus as a flame retardant aid, zinc stannate, zinc hydroxystannate,
The silicone compound is a fatty acid such as erucic acid, stearic acid, oleic acid or the like as a processing aid, or a metal salt thereof, and at least one selected from an antioxidant, a color pigment, carbon black and the like, in a necessary amount, preferably 20.
It can be added within a range not exceeding the weight part.

The flame-retardant insulated wire for a lead wire of the present invention obtained as described above has mechanical properties such as a tensile strength of 10 MPa or more, a breaking elongation of 300% or more, and a hardness (Shore D) of 50 or less. And is excellent in flexibility (flexibility), and further, the heat deformation rate is 40% or less, and it can be used in a high temperature atmosphere or the like. Also regarding flame retardancy, J
It can pass the IS standard C3005 60-degree inclined combustion test without fail, and it is possible to obtain a flame-retardant insulated wire having sufficient flame-retardant property and excellent in workability in the ejection. Since this flame-retardant insulated wire does not contain a halogen element, it does not generate harmful halogen gas during combustion, and does not cause environmental problems even if it is incinerated.

Next, the invention of claim 2 will be described.
Olefinic thermoplastic elastomer (TPO) 85-5
5 parts by weight of ethylene propylene diene copolymer (EPD
M) or maleic acid modified ethylene propylene rubber 9.
5 to 35 parts by weight and ethylene propylene diene copolymer grafted with silanol group-containing compound 0.5 to 5
And 100 parts by weight of an elastomer mixture consisting of 100 parts by weight of an olefinic flame-retardant composition containing 100 to 250 parts by weight of a metal hydrate on a conductor. A ternary mixture of an olefinic thermoplastic elastomer and an ethylene propylene diene copolymer or a maleic acid modified ethylene propylene copolymer and an ethylene propylene diene copolymer grafted with a silanol group-containing compound is used as a base polymer. is there. And this base polymer 1
By mixing 100 to 250 parts by weight of a metal hydrate with 100 parts by weight, an olefin flame-retardant resin composition is obtained, which is extruded and coated on a conductor such as copper to obtain a flame-retardant insulated wire. is there. The insulating coating layer has good heat resistance due to progress of crosslinking (silane crosslinking) due to moisture in the air or the like.

Explaining in detail, styrene-ethylene-
Butylene-styrene copolymer (SEBS), mixture of polypropylene and ethylene propylene rubber (PP / EP)
And 85 to 55 parts by weight of an olefinic thermoplastic elastomer such as ethylene glycol and ethylene propylene copolymer or ethylene propylene diene copolymer (EPDM) modified by about 0.1 to 2% maleic acid Usually, 0.5 to 5 parts by weight of the EPDM grafted with a silanol group-containing compound in an amount of 0.1 to 3% is mixed to form a base polymer. By using such a mixture, a silane-crosslinkable mixture can be obtained, and the mechanical properties can be easily adjusted to be in a target range. If the olefin-based thermoplastic elastomer deviates from the above ratio, heat resistance such as heat deformability is insufficient, which is not preferable. If the EPDM or maleic acid-modified EPDM deviates from the above range, the flexibility becomes insufficient, which is not preferable. And further, as described in claim 3,
The content of the olefinic thermoplastic elastomer is 20
%, It is preferable to use a polymer alloy of polypropylene and ethylene propylene diene copolymer. As described above, the polymer alloy containing 20% or more of PP is preferable for the problem of heat deformation, and specifically, a polymer alloy that passes the heat deformation test at 120 ° C. (JIS standard C3005) is obtained. This is because it is suitable as a coating material for an insulated wire used in a high temperature atmosphere as in the present invention.

The flame-retardant insulated wire produced as described above is subjected to crosslinking treatment such as electron beam irradiation crosslinking, chemical crosslinking, and silane crosslinking. By performing the cross-linking treatment in this manner, the heat resistance of this flame-retardant insulated wire can be improved. This is the flame-retardant insulated wire of the present invention as described above,
This is because it is used as a lead wire for a wiring board, a motor, or the like in a high temperature atmosphere, and the heat deformation rate is adjusted to be 40% or less. The crosslinking treatment is not particularly limited, but it is convenient to perform silane crosslinking. That is, the olefin-based thermoplastic elastomer and the EPDM
Alternatively, an olefin-based flame-retardant composition composed of a maleic acid-modified EPDM and a silanol group-containing compound grafted onto the EPDM and a metal hydrate is extruded and coated on a conductor and then exposed to water or exposed to moisture in the air. This is because the crosslinking will proceed by leaving it to stand for crosslinking.

As described above, the flame-retardant insulated wire of the present invention is
It is necessary to have the characteristics set forth in claim 4. That is, the main component of the base polymer is an olefin-based thermoplastic elastomer in order to prevent generation of harmful gases such as halogen gas during combustion, and flame retardancy is determined by addition of metal hydrates in the JIS C3005 60-degree inclined combustion test. Pass and be flexible for mechanical properties
In consideration of the above, the tensile strength is 10 MPa or more, the elongation at break is 300% or more, and the hardness (Shore D) is 50 or less, and the heat deformation rate is 40 in consideration of the environment in which it is used.
% Or less. The flame-retardant insulated electric wire satisfying such conditions can be a flame-retardant insulated electric wire which has a good workability for ejection and sufficiently functions even in a high temperature atmosphere.

[0016]

EXAMPLES The effects of the present invention will be described with reference to examples. The olefin-based flame-retardant composition described in Table 1 was 2 mm
^Using a flame-retardant insulated electric wire extruded and coated on the copper conductor No. ^{2 to} a thickness of 0.8 mm, tensile breaking strength (MPa), elongation (%), hardness (Shore D), heat deformation rate (%) and difficulty The flammability (JIS C3005 60-degree inclined combustion test) was measured. The tensile strength (MPa), elongation (%), hardness (Shore D) are measured based on JIS standard K7113. Regarding the above-mentioned flame retardance, those which are described as passed are those which self-extinguish within 60 seconds after ignition. The numerical value of the mixing ratio of each component is shown in parts by weight. Next, the base polymer will be described. An olefin-based thermoplastic elastomer (P is a polymer alloy of PP and an ethylene propylene diene copolymer).
P20% of PPO), ethylene propylene diene copolymer, maleic acid-modified ethylene propylene rubber, and ethyleneylene propylene diene copolymer grafted with silanol group-containing compound. Dibutyltin dilaurate was used as a condensation catalyst for silane crosslinking. Further examples of flame retardants composed of metal hydrates include
In each case, magnesium hydroxide and aluminum hydroxide surface-treated with a silane coupling agent were used.

[0017]

[Table 1]

As is apparent from Table 1, those described as Examples 1 to 14 were preferable in all test items. Explaining in detail below, in Examples 1 to 4 in which magnesium hydroxide and aluminum hydroxide are blended in the range of 100 to 250 parts by weight with the base polymer of TPO alone, the tensile strength is 10.9 to 14.3 MPa. 1
0 MPa or more, elongation of 360 to 450% and 300% or more, hardness (Shore D) of 44 to 47 and 50 or less, heat deformation rate of 6 to 12% and 40% or less, and also regarding flame retardancy, JISC3005 It was preferable to pass all the 60-degree inclined combustion test. Also regarding Examples 5 to 14 in which the base polymer is a mixture, for example Example 5
85 to 55 parts by weight of the TPO,
Tensile strength of 1 is obtained by using a mixture of ethylene propylene diene copolymer 9.5 to 35 parts by weight and silane graft EPDM 0.5 to 5 parts by weight as a base polymer.
1.6 to 15.2 MPa, 10 MPa or more, elongation 42
0-500% and 300% or more, hardness (Shore D) is 38
-42 and 50 or less, the heat deformation rate is 5 to 18% and 40% or less, and the flame retardancy is also 60 of JISC3005.
All of them passed the graded combustion test. Also, as described in Examples 10-14, the TPO is 85-5.
5 parts by weight, maleic acid modified ethylene propylene diene copolymer 9.5 to 35 parts by weight, silane graft EPDM
Those using the mixture of 0.5 to 5 parts by weight as the base polymer also have tensile strengths of 113.3 to 15.5 MPa and 1
0 MPa or more, elongation of 360 to 450% and 300% or more, hardness (Shore D) of 40 to 43 and 50 or less, heat deformation rate of 7 to 15% and 40% or less, and in terms of flame retardancy, JIS C3005 All passed the 60-degree inclined combustion test. Regarding the silane cross-links, those with cross-linking had a gel fraction within a range of 5 to 40% after 1 week.

On the other hand, in the case of the comparative example shown in Table 2, there was a problem in any of the above test items. That is, using the olefin flame-retardant resin composition described in Table 2, the flame-retardant insulated wire was produced in the same manner as in the above-mentioned example, and the same test items as those in the above-mentioned example were measured in the same manner. It is a thing.

[0020]

[Table 2]

As is apparent from Table 2, the resins shown in Comparative Examples 1 to 13 have tensile strengths (MPa) when the base polymers are out of the range of the compounding ratio of the present invention, either alone or in a mixture. The result is that any of the items of elongation (%), hardness (Shore D), heat deformation rate (%) and flame retardancy does not reach the target numerical values. More specifically, Comparative Examples 4, 5 and 10 which are examples when the amount of magnesium hydroxide added is small are JIS C 3005 6
The 0-degree inclined combustion test could not be passed. On the contrary, in Comparative Examples 6, 7, 8, 9 and 11 in which the amount of magnesium hydroxide added is large, the tensile strength is 10 MPa or less,
Elongation is less than 300% and hardness (Shore D) is 50
However, there are problems with mechanical properties.

Further, as in Comparative Examples 1 to 3, the TPO
When the amount of PP in the composition is as small as 15%, the heat deformation rate becomes 40% or more even if crosslinking is performed, which is not preferable. Further, when the addition amount of the TPO itself is insufficient or when the TPO having a small amount of PP is mixed as in Comparative Examples 12 and 13, the heat deformation rate exceeds 40%, which is not preferable. Therefore, in the present invention, the content is 20%
An olefin-based flame-retardant elastomer composition obtained by mixing 100 parts by weight of an olefin-based thermoplastic elastomer, which is a polymer alloy of the above polypropylene and an ethylene-propylene-diene copolymer, with 100 to 250 parts by weight of a metal hydrate, or an olefin-based flame-retardant elastomer composition. Thermoplastic elastomer 90-6
0 parts by weight of ethylene propylene diene copolymer or maleic acid modified ethylene propylene diene copolymer 9.5
-35 parts by weight and 100 parts by weight of a thermoplastic mixture consisting of 0.5 to 5 parts by weight of an ethylene propylene diene copolymer grafted with a silanol group-containing compound, and 100 to 250 parts by weight of a metal hydrate. It is understood that it is preferable to use the flame-retardant composition as a flame-retardant insulated wire coated on the conductor.

[0023]

The flame-retardant insulated wire of the present invention has a content of 2
100 to 25 parts by weight of an olefin-based thermoplastic elastomer, which is a polymer alloy of 0% or more of polypropylene and an ethylene-propylene-diene copolymer, and 100 to 25 of a metal hydrate.
Olefin-based flame-retardant elastomer composition containing 0 parts by weight, or olefin-based thermoplastic elastomer 85-
Thermoplastic comprising 55 parts by weight of ethylene propylene diene copolymer or maleic acid-modified ethylene propylene rubber 9.5 to 35 parts by weight and ethylene propylene diene copolymer grafted with silanol group-containing compound 0.5 to 5 parts by weight With respect to 100 parts by weight of the elastomer mixture,
An olefin-based flame-retardant elastomer composition containing 100 to 250 parts by weight of a metal hydrate is coated on a conductor to form a flame-retardant insulated wire, which has a tensile strength of 10 MPa or more. , Breaking elongation is 300%
As described above, a flame-retardant insulated wire having a hardness (Shore D) of 50 or less and excellent in flexibility (flexibility) is obtained, and such a flame-retardant insulated wire also has excellent workability in ejection. See also JI
Since the S-standard C3005 has a heat deformation rate of 40% or less, it can be used in a place exposed to a high temperature atmosphere. Further, regarding the flame retardancy, the flame retardant composition has a high flame retardance that passes the JIS standard C3005 60-degree inclined combustion test, and at the same time, a flame retardant composition containing no halogen element is used as an insulating coating material. Even if the flame-retardant insulated electric wire is discarded and incinerated, no harmful gas such as halogen gas is generated and no environmental problem occurs.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01B 3/00 H01B 3/44 F 3/44 GP 7/34 BF term (reference) 4J002 BB12W BB15X BB15Y BB204 BB21Y BP01W DE076 DE086 DE146 DE266 GQ01 5G303 AA06 AB20 CA09 CA11 5G305 AA02 AB25 AB36 CA01 CA08 CA45 CA51 CC03 5G315 CA03 CB01 CD02 CD03 CD14

Claims (4)

[Claims] 1. An olefin-based composition in which 100 to 250 parts by weight of a metal hydrate is mixed with 100 parts by weight of an olefin-based thermoplastic elastomer which is a polymer alloy of polypropylene having a content of 20% or more and an ethylene-propylene-diene copolymer. A flame-retardant insulated wire comprising a conductor coated with a flame-retardant composition. 2. An olefin-based thermoplastic elastomer 85
To 55 parts by weight of ethylene propylene diene copolymer or maleic acid modified ethylene propylene rubber 9.5 to 35
100 parts by weight of an elastomer mixture consisting of 0.5 parts by weight and 0.5 to 5 parts by weight of an ethylene propylene diene copolymer grafted with a silanol group-containing compound, and 100 to 250 parts by weight of a metal hydrate are blended to form an olefin-based compound. A flame-retardant insulated electric wire, characterized in that a conductor is coated with a flammable composition. 3. The flame-retardant insulation according to claim 2, wherein the olefin-based thermoplastic elastomer is a polymer alloy of polypropylene having a content of 20% or more and an ethylene propylene diene copolymer. Electrical wire. 4. The flame-retardant insulated wire according to any one of claims 1 to 3 has a flame retardance that passes a JIS C3005 60-degree inclined combustion test, a tensile strength of 10 MPa or more, and an elongation of 10 MPa or more. 300% or more, a hardness (Shore D) of 50 or less, and a heat deformation rate of 40% or less,
The flame-retardant insulated electric wire according to any one of claims 1 to 4.