JPH0581936A - Adhesive flame resistance cross-linked insulated wire - Google Patents

Abstract

PURPOSE:To provide an adhesive flame resistance cross linked insulated wire provided with required flame resistance while having excellent abrasion resistance and adhesiveness to an epoxy bond. CONSTITUTION:A polymer, in which one or not less than two of polyethylene, ethylene vinly acetate copolymer and an ethylene ethyl ecrylate copolymer are mixed, is used. An insulator containing an age resistor, in which one or not less than two of age resistors containing an NH redical such as 2- mercaptobenzimidazole, 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline in a base material, where a copolymer amount in the whole polymer is not exceeding 15wt.% and an oxygen index is not less than 22, in the range 0.5 to 10.0wt.% is provided to cover wire and cross-linked.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an insulated electric wire used in an electric system such as an automobile, and more particularly to an adhesive flame-retardant cross-linked insulated electric wire having improved adhesiveness with an epoxy adhesive.

[0002]

2. Description of the Related Art Crosslinked polyethylene has excellent heat resistance and electrical characteristics and is widely used as an insulating material. For example, the crosslinked polyethylene used for the electric system of an automobile corresponds to AEX shown in the "heat resistant low voltage electric wire for automobile" standard of JASO D-608-87.

By the way, since automobiles are constantly exposed to water due to rain, snow, car wash, etc., it is very important to waterproof the connecting portions of the electric wires used.

[0004] Conventionally, in order to waterproof the connecting portion, the ends of the electric wires are gathered in a connecting box for connection, and after these connecting processes are performed, an epoxy adhesive is poured into the gap between the connecting boxes. It was achieved by filling the gap.

[0005]

However, when the insulating coating of the electric wire to be connected is a cross-linked polyethylene coating, the cross-linked polyethylene coating and the epoxy adhesive are difficult to adhere to each other, so the epoxy adhesive is hardened. After that, peeling may occur between the crosslinked polyethylene film and the epoxy adhesive, and water may enter through this gap to impair the waterproof performance.

Therefore, as a result of intensive studies, the present inventors devised a specific composition having excellent adhesiveness with this epoxy adhesive, and effectively used the above-mentioned problems by using it as an insulating coating for electric wires. It became possible to solve it. That is, an object of the present invention is to provide an adhesive flame-retardant cross-linked insulated electric wire, which has greatly improved adhesiveness with an epoxy adhesive.

[0007]

In order to achieve the above object, the present invention provides a polymer obtained by mixing one or more of polyethylene, ethylene vinyl acetate copolymer and ethylene ethyl acrylate copolymer, and The amount of the copolymer is 15 wt% or less and the oxygen index is 22.
2-mercaptobenzimidazole in the above base material,
6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, N, N'-diphenyl-p-phenylenediamine, 2-mercaptomethylbenzimidazole,
N, N'-di-2-naphthyl-p-phenylenediamine, poly (2,2,4-trimethyl-1,2-dihydroquinoline), N- (3-methacryloyloxy-2-hydroxypropyl) -N ' One or two of NH group-containing antioxidants such as -phenyl-p-phenylenediamine and p- (p-toluenesulfonylamidodiphenylamine)
It is a cross-linked coating of an insulator containing 0.5 to 10.0 parts by weight of a combination of three or more antioxidants.

The base material is polyethylene, as described above.
It is a polymer in which one or more of ethylene vinyl acetate copolymer and ethylene ethyl acrylate copolymer are mixed, but if the amount of the copolymer in all polymers is 15 wt% or more, abrasion resistance may decrease, so 15 wt% or less And need to. In addition, it is necessary for these to have an oxygen index of 22 or more by a conventionally known method, for example, by adding an organic halogen compound and ammotine trioxide.
That is, if it is less than 22, the flame retardance required for the electric wire for automobile cannot be satisfied. In addition, NH contained in this base material
The group-containing antiaging agent is an adhesion-imparting agent, and as described above, its content needs to be in the range of 0.5 to 10.0 parts by weight. That is, if the amount is 0.5 parts by weight or less, the expected effect cannot be obtained, and if it is 10.0 parts by weight or more, the wear resistance decreases.

It is considered that these anti-aging agents are effective in improving the adhesiveness because they are reactive with the components of the epoxy adhesive, but as a result, they have found an excellent improvement in adhesive strength. Is. The chemical structures of these are as shown in FIG. 1 (A) is poly (2,2,4-trimethyl-1,2-dihydroquinoline), (B) is N- (3-methacryloyloxy-2-hydroxypropyl) -N '.
-Phenyl-p-phenylenediamine, (C) is p-
(P-toluenesulfonylamide diphenylamine),
(D) is N, N'-di-2-naphthyl-p-phenylenediamine, (E) is N, N'-diphenyl-p-phenylenediamine, (F) is 2-mercaptobenzimidazole, and (G) is 2-mercaptomethylbenzimidazole, (H) is 6-ethoxy-1,2-dihydro-2,
It is a structural formula of 2,4-trimethylquinoline.

Examples of these anti-aging agents include Nocrac MB, Nocrac AW, Nocrac DP, Nocrac MMB, Nocrac White, Nocrac 224, Nocrac G-1 and Nocrac TD of Ouchi Shinko Chemical Co., Ltd. It is easily available as a product.

Then, these insulators are cross-linked by a conventionally known cross-linking method such as peroxide or electron beam. In addition, general antioxidants, colorants, stabilizers, lubricants, polyfunctional monomers and the like can be appropriately added to these insulating coatings.

[0012]

With the above-described structure, the present invention improves the adhesiveness between the insulator and the epoxy adhesive by the NH group-containing anti-aging agent, and prevents peeling which impairs the waterproof effect. Further, since the amount of the copolymer in the total polymer is 15 wt% or less, the wear resistance is prevented from being lowered, and the oxygen index is 22 or more, so that it has the flame retardancy required for the electric wire for automatic use. It will be.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

As Example 1 of the present invention, polyethylene (Mirason 3530 d = Mitsui DuPont Polychemical Co.
0.924, MI = 0.3 g / min), 20 parts by weight of decabromodiphenyl ether (AFT-1021, Asahi Glass Co., Ltd.) and 15 parts by weight of ammotine trioxide (Sumitomo Metal Mining Co., Ltd.) were added, and 3 parts of Nocrac 224 were further added. By weight, 2 parts by weight of Nocrac MB and 2 parts by weight of tribasic lead sulfate were added and uniformly kneaded with a Banbury mixer at 170 ° C. Then, using an extruder equipped with a 40 mm crosshead, a diameter of 0.
Seven 32 mm tin-plated copper wires were twisted, extruded and coated on the conductor so as to have an insulation thickness of 0.5 mm, and 20 Mrad of the electron beam was irradiated onto the conductor to obtain a flame-retardant crosslinked polyethylene electric wire.

Next, an epoxy adhesive (Araldide Clean Cast SF, manufactured by Ciba-Geigy Co., Ltd.) was thinly applied to the surface of the flame-retardant cross-linked polyethylene wire to a thickness of about 0.3 mm and cured at 100 ° C. for 15 minutes. After returning to room temperature for 24 hours, the electric wire was bent into a round bar having a diameter of 15 mm, and the presence or absence of peeling between the insulator and the epoxy adhesive was observed.
Along with this, a tape abrasion test was performed on the electric wire alone by the method specified in JASO 0608-87. And since tape wear is required to be 610 mm or more, 610 mm
The above was passed, and 610 mm or less was rejected.

As a flame retardant test, JIS K-7210
A sheet for oxygen index was manufactured separately from these by press molding without irradiation cross-linking, and the flame retardancy was evaluated. As an evaluation criterion, it was determined whether or not the oxygen concentration was fixed at 22%, ignition was performed, and combustion continued for 1 minute or more. When the fire was extinguished within 1 minute, the oxygen index was set to 22 or higher.

[0017]

[Table 1]

Table 1 shows the results of these experiments. As is apparent from these, the above-described Example 1 is
Good experimental results were obtained for both tape wear and epoxy adhesion. Further, Examples 2 to 7 are ethylene vinyl acetate copolymers (P-1405, manufactured by Mitsui DuPont Polychemical Co., Ltd.).
VA = 14 wt% MI = 3.5 d = 0.93) was used as a base material, and 4 parts by weight of each of the various antioxidants shown in Table 1 were added thereto, and thereafter the same production as in Example 1 was performed. It is a thing. Then, as shown in Table 1, in each of Examples 2 to 7, the tape abrasion and the epoxy adhesiveness were good as in Example 1. Further, Example 8 is an ethylene ethyl acrylate copolymer (Nippon Petrochemical Co., Ltd. Lexron EEA A1100 EV amount = 10 wt%, MI =
0.4) was added with 1 part by weight of Nocrac 224, and Example 9 was obtained by adding 8 parts by weight of Nocrac MB to the matrix of this ethylene ethyl acrylate copolymer. Then, when an electric wire was manufactured and evaluated in these Examples 8 and 9 by the same method as in Example 1, as in Examples 1 to 7, good adhesion and abrasion resistance were exhibited.

Further, Comparative Example 10 produced as a comparative example of Examples 1 to 9 is a case where an ethylene vinyl acetate copolymer having a VA amount of 19 wt% which exceeds the specified amount of the present invention is used as a base material. Had good adhesiveness, but the wear resistance was greatly reduced. Further, Comparative Examples 11 and 12 show cases where the antioxidant was not added to the above-mentioned base material at all, and in these, the adhesive was peeled from the insulating coating.

That is, as is clear from Table 1, when the content of the copolymer in the base material is 15 wt% or more, the wear resistance is lowered, and the antioxidant added to the base material is If the amount is out of the specified range, the adhesiveness and wear resistance will decrease.

Therefore, the present invention has a copolymer content of 15
To obtain an insulator excellent in adhesiveness and abrasion resistance by adding a specified amount of an NH group-containing anti-aging agent having adhesion-imparting performance found by the present inventors to a base material of wt% or less You can

[0022]

In summary, according to the present invention, it is possible to obtain an electric wire which has flame retardancy and abrasion resistance required for electric wires used in automobiles and has excellent adhesiveness with an epoxy adhesive. Therefore, the waterproof performance of the electric wire terminal is greatly improved, and the durability and reliability are remarkably improved.

[Brief description of drawings]

FIG. 1 shows respective structural formulas of an NH group-containing antiaging agent of the present invention.

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display area C08L 23/04

Claims (1)

[Claims] 1. A polymer obtained by mixing one or more of polyethylene, ethylene vinyl acetate copolymer and ethylene ethyl acrylate copolymer, wherein the total polymer has an amount of 15 wt% or less and an oxygen index of 2.
2-mercaptobenzimidazole, 6-ethoxy-in two or more base materials
1,2-dihydro-2,2,4-trimethylquinoline,
N, N'-diphenyl-p-phenylenediamine, 2-
Mercaptomethylbenzimidazole, N, N'-di-
2-naphthyl-p-phenylenediamine, poly (2,
2,4-trimethyl-1,2-dihydroquinoline), N
-(3-methacryloyloxy-2-hydroxypropyl) -N'-phenyl-p-phenylenediamine and p
-(P-toluenesulfonylamide diphenylamine)
An adhesive flame-retardant characterized by being cross-linked with an insulator containing 0.5 to 10.0 parts by weight of an anti-aging agent containing one or more NH group-containing anti-aging agents such as Cross-linked insulated wire.