JPS6280916A - Fluorine containing elastomer-coated wire - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an electric wire coated with a resin composition mainly composed of a tetrafluoroethylene-propylene copolymer, particularly an electric wire with excellent heat deformation resistance. It is.

[Prior Art] Tetrafluoroethylene-propylene copolymer is known as a crosslinkable fluorine-containing elastomer copolymer that has high thermal stability, oil resistance, insulation, chemical resistance, and flame retardancy. By coating the outer periphery of a conductor or wire core with such a copolymer, it is possible to obtain wires and cables having the above-mentioned features, and this is currently being studied in various fields.

Tetrafluoroethylene-propylene copolymers have a problem with heat deformation resistance, and to solve this problem, white fillers such as thermal carbon, talc, and clay, which have been known as fillers for fluororubber, have been used. A coating layer is formed using the resin composition used.

[Problems to be solved by the invention] However, compared to general fluororesins such as tetrafluoroethylene-hexafluoropropylene, the heat deformation resistance is inferior, and high It requires heat deformation resistance, which poses a problem in its application in the field.

An object of the present invention is to provide a fluorine-containing elastomer-coated electric wire that has a high degree of heat deformation resistance.

[Means for solving the problems] The electric wire of the present invention is made of tetrafluoroethylene-brobylene copolymer 100! 5 to 4 off of silicon dioxide surface-treated with dialkyldichlorosilane based on the amount of Ii.
It is constructed by providing a coating layer of a resin composition containing i part of the resin composition and crosslinking the coating layer.

In the present invention, the tetrafluoroethylene-propylene copolymer includes, in addition to the main components tetrafluoroethylene and propylene, components copolymerizable with these, such as ethylene, butene-1, isobutyne, acrylic acid, and alkyl thereof. esters, methacrylic acid and its alkyl esters, vinyl buttonide, vinylidene buttonide, hexafluoropropene, chloroethyl vinyl ether,
It may contain glycidyl vinyl ether, chlorotrifluoroethylene, perfluoroalkyl vinyl ether, etc. as appropriate.

In such a copolymer, the molar ratio of tetrafluoroethylene/propylene is 9515 to 30/70,
In particular, it is preferable to select from the range of 90/10 to 45155 from the viewpoint of heat resistance, moldability, etc., and the content of components other than the main component, which may be added as appropriate, is usually 50 mol%.
Hereinafter, it is particularly preferable to select from a range of 30 mol% or less.

The surface treatment of silicon dioxide with dialkyldichlorosilane can be carried out, for example, with water vapor under an inert gas atmosphere.
This is done by heating to 0°C. The amount of silicon dioxide mixed with the surface treated with this dialkyldichlorosilane is:
Tetrafluoroethylene-propylene copolymer 100
The amount must be in the range of 5 to 40 parts by weight based on the amount of ffi; if it is less than 5 parts by weight, the effect of improving heat deformation resistance will be small, and if it exceeds 40 parts by weight, the viscosity will increase significantly and extrusion processing will be difficult. Become.

Specific examples of dialkyldichlorosilane include dimethyldichlorosilane, diethyldichlorosilane, diphenyldichlorosilane, etc., with dimethyldichlorosilane being preferred.

Note that silicon dioxide without surface treatment with dialkyldichlorosilane is also effective in improving heat deformation resistance, but has the problem of significantly increasing the viscosity of the composition, making extrusion processing difficult.

A resin composition containing the above-described tetrafluoroethylene-propylene copolymer and silicon dioxide surface-treated with dimethyldichlorosilane as essential components is extruded and coated on the outer periphery of a conductor or electric wire core, and then crosslinked.

As a crosslinking method, addition of organic peroxides, amines, etc.
or irradiation crosslinking by irradiation with ionizing radiation such as gamma rays or electron beams, etc., and is not particularly limited.

Specific examples of organic peroxides include di-t-butyl peroxide, t-butylcumyl peroxide, dicumyl peroxide, 2,5-dimethyl-2,5-di(t
-butylperoxy)-hexyne-3,1,3-bis-
Examples include (t-butylperoxy-isopropyl)benzene.

Specific examples of amines include hexamethylene diamine,
So-called alkyl polyamines such as tetraethylenepentamine and triethylenetetramine, or their salts such as carbamic acid and cinnamylidenic acid, or 7 such as piperazine, piperidine, pyridine, aniline, and phenanthroline.
Examples include polyamines and their salts.

It is also possible to employ crosslinking aids such as allyl compounds, sulfur, organic amines, maleimide, methacrylates, divinyl compounds, etc. Preferably, diallyl phthalate, triallyl phosphoric acid, triallyl isocyanurate, triallyl cyanurate, etc. Allyl compounds can be employed.

In the present invention, in addition to the above-mentioned components, silicate-based filler,
carbon black, calcium carbonate, aluminum hydroxide, magnesium hydroxide, etc.), pigments, lubricants, extrusion aids,
Various additives such as antioxidants and stabilizers may be added.

In addition, resins such as polyvinylidene buttrate, fluororesins such as ethylene-tetrafluoroethylene copolymer, and fluororubbers such as vinylidene buttride-hexafluoropropylene may be mixed.

[Example] The composition shown in Table 1 was kneaded using an 8-inch roll heated to 60°C.

Next, head: 100°C, cylinder 1: 100°C, cylinder 2: 80°C were set at 40 m/m extrusion 4 m (L/
D=22), the outer periphery of a tin-plated copper stranded wire having an outer diameter of 1.6 mmφ was extrusion coated to a thickness of 0.5 mm, and then held in steam at 13 atmospheres for 3 minutes for crosslinking.

The heat deformation rate of the electric wire thus produced was measured based on JIS standards. In addition, extrusion processability was also evaluated. The results are shown in the lower column of Table 1.

As is clear from Table 1, Example 1 within the scope of the present invention
-5, the heat deformation resistance is extremely good, and the extrusion processability is also excellent.

On the other hand, in Comparative Example 1, which was surface-treated with dimethyldichloride aa silane and had a lower content of silicon dioxide than the specified value of the present invention, and Comparative Examples 2 to 4, in which a filler other than the specified filler of the present invention was used, both were heated and deformed. The rate is large. In addition, in Comparative Example 5 using silicon dioxide without surface treatment, the viscosity of the composition was high, so heat generation in the extruder was large, and as a result, early crosslinking occurred in the extruder, making extrusion processing impossible.

[Effects of the Invention] As explained above, according to the present invention, the heat deformation resistance can be significantly improved while maintaining excellent extrusion processability, and as a result, the range of use of the fluorine elastomer-coated electric wire can be further expanded. It becomes possible.

Claims (1)

[Claims] (1) having a coating layer of a resin composition containing 5 to 40 parts by weight of silicon dioxide surface-treated with dialkyldichlorosilane based on 100 parts by weight of a tetrafluoroethylene-propylene copolymer; is a fluorine-containing elastomer-coated electric wire characterized by being cross-linked.