JPH09288915A - Fluorine-containing-elastomer-covered wire or cable - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluoride-containing-elastomer-covered wire or cable excellent in cut-through resistance and in cold resistance when filled with a filler to high degrees. SOLUTION: A fluoropolymer comprises 60 to 95wt.% tetrafluoroethylene- propylene copolymer and 5 to 40wt.% ethylene-tetrafluoroethylene copolymer. In this case, this cable 1 has a sheath layer 3 formed on the outer periphery of a conductor 2 and made of a composition formed by adding 60 to 200 parts by weight of calcium carbonate with an average grain size of 1 to 5mm as a filler to 100 parts by weight of the fluoropolymer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorine-containing elastomer covered electric wire / cable.

[0002]

2. Description of the Related Art Generally, as a coating material for electric wires and cables, a tetrafluoroethylene-propylene copolymer is used in addition to chloroprene rubber, chlorostyrenated polyethylene rubber and the like. In particular, a tetrafluoroethylene-propylene-based copolymer is excellent in flexibility, thermal stability, electrical insulation, heat resistance, oil resistance, chemical resistance, and flame retardancy, and is a crosslinkable fluorine-containing elastomer. It is a copolymer.

Conventionally, by coating this copolymer on the conductor or on the outer periphery of an electric wire and crosslinking by heating with a peroxide or by irradiating with ionizing radiation or the like,
I was getting a fluorine-containing elastomer-coated wire / cable.

[0004]

However, in a fluorine-containing elastomer-coated electric wire / cable made of a tetrafluoroethylene-propylene copolymer, the insulating layer is often formed thin because of its excellent heat resistance. Therefore, there is a problem that the cut-through resistance is insufficient.

The tetrafluoroethylene-propylene type copolymer is generally expensive. Here, the cost performance can be improved by, for example, filling the tetrafluoroethylene-propylene-based copolymer with a high amount of filler (filler), but in that case, the cold resistance of the tetrafluoroethylene-propylene-based copolymer can be improved. Therefore, it was impossible to maintain both high performance and low manufacturing cost.

[0006] Therefore, the present invention is to solve the above problems and to provide a fluorine-containing elastomer-coated electric wire / cable which is excellent in cut-through resistance and cold resistance when a filler is highly filled.

[0007]

In order to solve the above problems, the invention of claim 1 provides 60 to 95% by weight of a tetrafluoroethylene-propylene copolymer and 5 to 40% by weight of ethylene-tetrafluoroethylene. 60 parts by weight of calcium carbonate having an average particle size of 1 to 5 mm as a filler with respect to 100 parts by weight of a fluoropolymer composed of a base copolymer.
A coating layer is formed on the outer periphery of a conductor with a composition obtained by adding 200 parts by weight.

A second aspect of the present invention is the fluorine-containing elastomer coated electric wire / cable according to the first aspect, wherein the coating layer on the outer periphery of the conductor is crosslinked by ionizing radiation.

According to the invention of claim 3, the calcium carbonate is surface-treated with a fatty acid or a fatty acid metal salt, and the fluorine-containing elastomer-coated electric wire according to claim 1
Cable.

[0010] In the invention of claim 4, the ethylene-tetrafluoroethylene copolymer is composed of ethylene units, tetrafluoroethylene units, and fluoroolefin units.
Tetrafluoroethylene / fluoroolefin) is 1
The fluorine-containing elastomer-coated electric wire / cable according to claim 1, which is 0-40 / 90-60 / 0.1-20.

The reason for limiting the above numerical range will be described below.

The reason for limiting the weight ratio of the tetrafluoroethylene-propylene copolymer to the ethylene-tetrafluoroethylene copolymer to the range of 60/40 to 95/5 is that the tetrafluoroethylene-propylene copolymer is used. Less than 60% by weight of polymer (more than 40% by weight of ethylene-tetrafluoroethylene copolymer)
This is because the flexibility is impaired and the elongation is significantly reduced. Further, when the weight ratio of the tetrafluoroethylene-propylene-based copolymer is more than 95% (the weight ratio of the ethylene-tetrafluoroethylene-based copolymer is less than 5%), the strength is lowered and a large amount of the filler is used. This is because the cold resistance when added to is significantly reduced.

The reason why the average particle size of calcium carbonate is limited to 1 to 5 mm is that if it is smaller than 1 mm, the heat resistance is greatly deteriorated when calcium carbonate is highly filled, and if it is larger than 5 mm, the tensile strength is increased. This is because the

The reason why the amount of calcium carbonate added is limited to 60 to 200 parts by weight or less based on 100 parts by weight of a fluoropolymer composed of a tetrafluoroethylene-propylene copolymer and an ethylene-tetrafluoroethylene copolymer. The reason for this is that if the amount added is less than 60 parts by weight, there is little effect on improving cut-through resistance.
This is because if the amount is more than 00 parts by weight, mechanical properties such as tensile strength and elongation are deteriorated, and cold resistance is significantly deteriorated.

According to the above constitution, the weight ratio of the tetrafluoroethylene-propylene-based copolymer and the ethylene-tetrafluoroethylene-based copolymer of the composition for coating the outer periphery of the conductor, the average of calcium carbonate as the filler Particle size,
Further, since the mixing ratio of the fluorine-based polymer and calcium carbonate is adjusted, it is possible to obtain a fluorine-containing elastomer-coated electric wire / cable excellent in cut-through resistance and cold resistance when the filler is highly filled.

[0016]

Embodiments of the present invention will be described below.

As shown in FIG. 1, a fluorine-containing elastomer-coated cable 1 which is a fluorine-containing elastomer-coated electric wire / cable of the present invention comprises a fluorine-containing elastomer composition (composition) on the outer periphery of a copper stranded wire (conductor) 2. To form a fluorinated elastomer-coated electric wire 1a, and the fluorine-containing elastomer-coated electric wire 1a is twisted with a plurality of (two in the figure) through the interposition 4 to form a stranded wire 5, The stranded wire 5 is covered with a sheath 6.

The coating layer 3 is made of a composition obtained by adding a filler to a fluorine-based polymer composed of a tetrafluoroethylene-propylene-based copolymer and an ethylene-tetrafluoroethylene-based copolymer.

The tetrafluoroethylene-propylene-based copolymer is composed of tetrafluoroethylene and propylene which are the main components, and a component which can be copolymerized with these.

As the component copolymerizable with tetrafluoroethylene and propylene, for example, ethylene, butene-1, isobutene, acrylic acid and its alkyl ester, methacrylic acid and its alkyl ester, vinyl fluoride, vinylidene fluoride and hexafluoro. Examples include propene, chloroethyl vinyl ether, glycidyl vinyl ether, chlorotrifluoroethylene, perfluoroalkyl vinyl ether and the like.

The tetrafluoroethylene-propylene-based copolymer has a molar ratio of tetrafluoroethylene and propylene of 95/5 to 30 / from the viewpoints of heat resistance and moldability.
It is preferably in the range of 70, especially 90/10
It is preferably in the range of 45/55.

The content of the components other than the main component is preferably 50 mol% or less, and particularly preferably 30 mol% or less with respect to the main component.

As the ethylene-tetrafluoroethylene copolymer, it is preferable to use an ethylene-tetrafluoroethylene-fluoroolefin copolymer.

Examples of fluoroolefins include chlorotrifluoroethylene, vinylidene fluoride, trifluoroethylene, 1,1-dihydroperfluoropropene-1,1,1-dihydroperfluorobutene, 1,
1,5-trihydroperfluoropentene-1,1,
1,7-trihydroperfluoropentene-1,1,
1,2-trihydroperfluorohexene-1,1,
1,2-trihydroperfluorooctene-1, perfluoro (methyl vinyl ether), perfluoro (ethyl vinyl ether), hexafluoropropene, perfluorobutene-1,3,3,3-trifluoro-2-trifluoromethyl Propene-1 and the like can be mentioned.

The ethylene-tetrafluoroethylene copolymer is composed of ethylene units, tetrafluoroethylene units, and fluoroolefin units, and the content molar ratio of each (ethylene / tetrafluoroethylene / fluoroolefin) is , 10-40 / 90-60 /
It is preferably 0.1 to 20.

The filler (filler) added to the fluorine-based polymer is preferably calcium carbonate, and more preferably calcium carbonate whose surface is treated with a fatty acid or a fatty acid metal salt.

In the composition constituting the coating layer 3 of the fluorine-containing elastomer-coated electric wire / cable 1 of the present invention, if necessary, a crosslinking aid, a pigment, an antioxidant, a lubricant, a processing aid, It goes without saying that a stabilizer or the like may be added.

[0028]

【Example】

(Example 1) Ethylene-tetrafluoroethylene-1,1-dihydroperfluoro having a melting point of 225 ° C and a melt index of 30 relative to 90 parts by weight of a tetrafluoroethylene-propylene copolymer having a number average molecular weight of 100,000. 10 parts by weight of propene-1, 1 part by weight of triallyl isocyanurate as a cross-linking aid, 1 part by weight of stearic acid Ba as a lubricant, and carbonic acid having a mean particle size of 1.8 μm surface-treated with calcium stearate as a filler. Add 60 parts by weight of calcium A and add 50 to 60
The mixture is uniformly kneaded for 15 minutes by a roll heated to ℃ to form a compound. The oil absorption of calcium carbonate A is 26
ml / 100 g.

Thereafter, the compound
A 40 mm extruder (L / D = 22) in which the first cylinder is set to 280 ° C. and the second cylinder is set to 300 ° C. at 50 ° C.
Press into each. After that, the cross-sectional area is 0.75 mm
A copper stranded wire (conductor) of ² is extruded to a thickness of 0.4 mm to form a coating layer, and the coating layer is irradiated with an electron beam of 10 Mrad to perform cross-linking to produce a fluorine-containing elastomer-coated electric wire. To do.

(Example 2) 10 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1 and 1 part by weight of a crosslinking aid were used with respect to 90 parts by weight of a tetrafluoroethylene-propylene copolymer. Part, 1 part by weight of lubricant, calcium carbonate B having an average particle size of 1.0 μm, which has been surface-treated with calcium stearate as a filler.
80 parts by weight is added, and this is uniformly kneaded for 15 minutes by a roll heated to 50 to 60 ° C. to form a compound. The oil absorption of calcium carbonate B is 26 ml /
100 g.

Thereafter, a fluorine-containing elastomer covered electric wire is prepared in the same manner as in Example 1.

(Example 3) 30 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1 and 1 part by weight of a crosslinking aid were added to 70 parts by weight of a tetrafluoroethylene-propylene copolymer. Part, 1 part by weight of lubricant, calcium carbonate B having an average particle size of 1.0 μm, which has been surface-treated with calcium stearate as a filler.
Of 140 parts by weight, and this was kneaded uniformly for 15 minutes with a roll heated to 50 to 60 ° C. to form a compound.

Thereafter, a fluorine-containing elastomer covered electric wire is prepared in the same manner as in Example 1.

(Example 4) 15 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1 and 1 part by weight of a cross-linking aid with respect to 85 parts by weight of a tetrafluoroethylene-propylene copolymer. Part, 1 part by weight of lubricant, calcium carbonate A having an average particle size of 1.0 μm, which has been surface-treated with calcium stearate as a filler.
And 100 parts by weight of the above are added, and this is uniformly kneaded for 15 minutes by a roll heated to 50 to 60 ° C. to form a compound.

Then, the compound
A 40 mm extruder (L / D = 22) in which the first cylinder is set to 280 ° C. and the second cylinder is set to 300 ° C. at 50 ° C.
Press into each. After that, the cross-sectional area is 0.75 mm
^A coating layer is formed by extruding a copper stranded wire (conductor) ² having a thickness of 0.4 mm on the outer periphery of the copper stranded wire to prepare a fluorine-containing elastomer-coated electric wire. This fluorine-containing elastomer covered electric wire is interposed 2
The main twist is made into a twisted wire, and a 150 mm extruder is used to coat the outer circumference of the twisted wire with a sheath having a thickness of 1 mm. Then, the sheath is crosslinked by irradiating an electron beam of 15 Mrad from above the sheath to produce a fluorine-containing elastomer-coated cable having an outer diameter of 10 mm.

(Example 5) 20 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1 and 1 part by weight of a cross-linking aid with respect to 80 parts by weight of a tetrafluoroethylene-propylene copolymer. Part, 1 part by weight of lubricant, calcium carbonate B having an average particle size of 1.0 μm, which has been surface-treated with calcium stearate as a filler.
Of 120 parts by weight, and the mixture was uniformly kneaded for 15 minutes by a roll heated to 50 to 60 ° C. to form a compound.

Thereafter, as in Example 4, the outer diameter was 10 m.
m Fluorine-containing elastomer coated cable is prepared.

(Comparative Example 1) 1 part of the crosslinking aid was added to 100 parts by weight of the tetrafluoroethylene-propylene copolymer.
Parts by weight, 1 part by weight of lubricant, 80 parts by weight of calcium carbonate A having a mean particle size of 1.8 μm surface-treated with calcium stearate as a filler,
A roll is heated to 0 to 60 ° C. to uniformly knead for 15 minutes to form a compound.

Thereafter, in the same manner as in Example 1, a fluorine-containing elastomer covered electric wire is produced.

Comparative Example 2 50 parts by weight of tetrafluoroethylene-propylene copolymer, 50 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1, and 1 part by weight of a crosslinking aid. Part, 1 part by weight of lubricant, surface treated with calcium stearate as a filler, calcium carbonate D having an average particle size of 0.6 μm
And 100 parts by weight of the above are added, and this is uniformly kneaded for 15 minutes by a roll heated to 50 to 60 ° C. to form a compound. The oil absorption of calcium carbonate D is 26 ml.
/ 100 g.

Thereafter, a fluorine-containing elastomer covered electric wire is prepared in the same manner as in Example 1.

(Comparative Example 3) 20 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1 and 1 part by weight of a cross-linking aid were added to 80 parts by weight of a tetrafluoroethylene-propylene copolymer. Part, 1 part by weight of lubricant, calcium carbonate B having an average particle size of 1.0 μm, which has been surface-treated with calcium stearate as a filler.
And 40 parts by weight of the above are added, and this is uniformly kneaded for 15 minutes by a roll heated to 50 to 60 ° C. to form a compound.

Thereafter, in the same manner as in Example 1, a fluorine-containing elastomer covered electric wire / cable is manufactured.

(Comparative Example 4) 20 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1 and 1 part by weight of a cross-linking aid with respect to 80 parts by weight of a tetrafluoroethylene-propylene copolymer. Part, 1 part by weight of lubricant, calcium carbonate B having an average particle size of 1.0 μm, which has been surface-treated with calcium stearate as a filler.
And 210 parts by weight of the above are added, and this is uniformly kneaded for 15 minutes by a roll heated to 50 to 60 ° C. to form a compound.

Then, a fluorine-containing elastomer-coated electric wire is prepared in the same manner as in Example 1.

(Comparative Example 5) 30 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1 and 1 part by weight of a crosslinking aid were added to 70 parts by weight of a tetrafluoroethylene-propylene copolymer. Part, 1 part by weight of lubricant, calcium carbonate C having an average particle diameter of 5.7 μm, which has been surface-treated with calcium stearate as a filler.
And 100 parts by weight of the above are added, and this is uniformly kneaded for 15 minutes by a roll heated to 50 to 60 ° C. to form a compound. The oil absorption of calcium carbonate C is 26 ml.
/ 100 g.

Then, a fluorine-containing elastomer covered electric wire is prepared in the same manner as in Example 1.

(Comparative Example 6) 20 parts by weight of ethylene-tetrafluoroethylene-1,1-dihydroperfluoropropene-1 and 1 part by weight of a crosslinking aid are used with respect to 80 parts by weight of a tetrafluoroethylene-propylene copolymer. Parts, 1 part by weight of lubricant, 100 parts by weight of calcium carbonate E having an average particle size of 1.2 μm surface-treated with silane as a filler, and uniformly added thereto for 15 minutes by a roll heated to 50 to 60 ° C. Kneading to form a compound. still,
The oil absorption of calcium carbonate E is 26 ml / 100 g.

Then, a fluorine-containing elastomer covered electric wire is prepared in the same manner as in Example 1.

Table 1 shows the specifications of the fluorine-containing elastomer-coated electric wires and cables prepared in Examples 1 to 5 and Comparative Examples 1 to 6, respectively.

[0051]

[Table 1]

Next, the mechanical properties, cold resistance, heat aging resistance, and cut-through resistance of the fluorine-containing elastomer-coated electric wires and cables prepared in Examples 1-5 and Comparative Examples 1-6 were evaluated. The evaluation of each characteristic was performed by the method shown below.

Tensile Properties A tensile test according to JIS-K-6301 was performed on the coating layers obtained by removing the conductors from the fluorine-containing elastomer-coated electric wires, and the tensile strength (MPa) and the elongation (%) were measured. In addition, the sheath was removed from each of the fluoroelastomer-coated cables, and a sample (thickness 0.8 mm) in which the sheath was worn was prepared, and a tensile test according to JIS-K-6301 was performed to determine the tensile strength ( MPa) and elongation (%) were measured. The values of tensile strength and elongation in this tensile test are used as initial values.

Cold resistance A sample (thickness: 2 mm) having the same composition as the coating layer of each fluorine-containing elastomer-coated electric wire and cable was prepared, and the sample was irradiated with an electron beam of 15 Mrad to carry out crosslinking treatment, and then JIS. The embrittlement temperature was investigated according to -K-6301.

Heat aging resistance (heat resistance) After each of the fluorine-containing elastomer-coated electric wires and the fluorine-containing elastomer-coated electric wires of the cables was kept in a gear oven (232 ° C.) with an air displacement of 200 times / hr for 7 days, JIS -Perform a tensile test according to K-6301,
The residual tensile strength (%) and the residual elongation (%) were measured with respect to the initial values.

Cut-through resistance The cut-through resistance (g) of the fluorine-containing elastomer-coated electric wire and the cable-containing fluorine-containing elastomer-coated electric wire of the cable in an atmosphere of 200 ° C. is ULsabj.
It investigated according to ect758.

Table 2 shows the results of each test on the fluorine-containing electric wires and cables prepared in Examples 1 to 5 and Comparative Examples 1 to 6.

[0058]

[Table 2]

As shown in Table 2, Example 1 of the present invention
~ 5 fluorine-containing elastomer coated wires and cables
Both have tensile strength of 13.6 or more, elongation of 200 or more,
Brittleness temperature is around -40 ° C, residual tensile strength is 100 or more,
The residual elongation was 90 or more and the cut-through resistance was 450 or more, and the mechanical properties, cold resistance, heat resistance, and cut-through resistance were all excellent.

On the other hand, in the fluorine-containing elastomer-coated electric wire of Comparative Example 1, the weight ratio of the tetrafluoroethylene-propylene copolymer and the ethylene-tetrafluoroethylene copolymer in the coating layer was unspecified (tetrafluoroethylene -Use of propylene copolymer only),
The tensile strength and cut-through resistance are not very good,
Extremely low cold resistance.

In the fluorine-containing elastomer-coated electric wire of Comparative Example 2, the weight ratio of the tetrafluoroethylene-propylene copolymer and the ethylene-tetrafluoroethylene copolymer in the coating layer was unspecified (tetrafluoroethylene-propylene copolymer). Is too small and the ethylene-tetrafluoroethylene copolymer is too much) and the average particle size of calcium carbonate is smaller than the specified range, so that the cold resistance is not very good and the elongation and heat resistance are extremely low.

In the fluorine-containing elastomer-coated electric wire of Comparative Example 3, the weight ratio of the tetrafluoroethylene-propylene copolymer to the ethylene-tetrafluoroethylene copolymer in the coating layer was within the specified range, but the amount of calcium carbonate added. Since it is too small, the cut-through resistance is extremely low.

In the fluorine-containing elastomer-coated electric wire of Comparative Example 4, the weight ratio of the tetrafluoroethylene-propylene copolymer to the ethylene-tetrafluoroethylene copolymer in the coating layer was within the specified range, but the amount of calcium carbonate added. Is too much, all properties except cut-through resistance are extremely low.

In the fluorine-containing elastomer-coated electric wire of Comparative Example 5, the weight ratio of the tetrafluoroethylene-propylene copolymer to the ethylene-tetrafluoroethylene copolymer in the coating layer was within the specified range, but the average particle size of calcium carbonate was Since the diameter is larger than the specified range, the tensile strength and elongation are not so good, and the cold resistance is extremely low.

In the fluorine-containing elastomer-coated electric wire of Comparative Example 6, the weight ratio of the tetrafluoroethylene-propylene copolymer to the ethylene-tetrafluoroethylene copolymer and the average particle diameter of calcium carbonate in the coating layer were within the specified ranges. However, since the surface treatment agent for calcium carbonate is out of the specified range, the elongation is not very good and the heat resistance (especially the residual elongation rate) is extremely low.

As described above, the fluorine-containing elastomer-coated electric wire / cable of the present invention has sufficient mechanical properties, cold resistance, heat resistance and excellent cut-through resistance.
It can be used in a variety of changing environments,
Its use range is wide.

[0067]

In summary, according to the present invention, it is possible to obtain a fluorine-containing elastomer-coated electric wire / cable having excellent cut-through resistance and cold resistance when a filler is highly filled.

[Brief description of drawings]

FIG. 1 is a view showing a cross section of a fluorine-containing elastomer covered electric wire / cable of the present invention.

[Explanation of symbols]

 1 Fluorine-containing elastomer covered cable 1a Fluorine-containing elastomer covered electric wire 2 Copper stranded wire (conductor) 3 Covering layer 4 Intervening 5 Stranded wire 6 Sheath

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area C09D 123/04 PER C09D 123/04 PER 123/08 PER 123/08 PER 127/18 PFJ 127/18 PFJ H01B 3/44 H01B 3/44 P 7/02 7/02 Z

Claims (4)

[Claims] 1. A fluoropolymer based on 100 parts by weight of 60 to 95% by weight of a tetrafluoroethylene-propylene copolymer and 5 to 40% by weight of an ethylene-tetrafluoroethylene copolymer. , Calcium carbonate having an average particle size of 1 to 5 mm as a filler is 60 to 200
A fluorine-containing elastomer-coated electric wire / cable, characterized in that a coating layer is formed on the outer periphery of the conductor with a composition containing parts by weight. 2. The fluorine-containing elastomer-coated electric wire / cable according to claim 1, wherein the coating layer on the outer circumference of the conductor is crosslinked by ionizing radiation. 3. The fluorine-containing elastomer-coated electric wire / cable according to claim 1, wherein the calcium carbonate is surface-treated with a fatty acid or a fatty acid metal salt. 4. The ethylene-tetrafluoroethylene copolymer is composed of an ethylene unit, a tetrafluoroethylene unit and a fluoroolefin unit, and the content molar ratio of each of them (ethylene / tetrafluoroethylene / fluoro). Olefin) is 10-40 / 90
The fluorinated elastomer-coated electric wire / cable according to claim 1, which is -60 / 0.1-20.