JPS60144333A - Production of crosslinked polyethylene cable - Google Patents

Abstract

PURPOSE:To produce the titled cable economically, by extrusion-coating the surface of a conductor with silane-grafted polyethylene and effecting its crosslinking reaction by spraying it with (warm) water shower. CONSTITUTION:A conductor W drawn from a delivery reel 1 by a drawing device 2 is surface-coated with a resin composition comprising polyethylene, an organosilane (e.g., vinylmethoxy-silane), an organic peroxide (e.g., dicumyl peroxide) and a silanol condensation catalyst (e.g., dibutyltin dilaurate) by using the first extruder 3. The obtained cable core C is sprayed with (warm) shower 4 to form a coating comprising an organosilane-crosslinked polyethylene on the surface of conductor W. The coated conductor is extrusion-coated at once with polyvinyl chloride sheath by using the second extruder 5. After cooling in a water tank 6, the obtained cable is wound around a winder 8 through a take-up device 7.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to cross-linked polyethylene insulation by cross-linking.
The present invention relates to a method of manufacturing a 7IAL cable, and particularly to a method of manufacturing a cape cable that improves the 7111WR% deformation rate of an insulator.

The conventional method for producing cross-linked polyethylene cables by silane cross-linking is a method of producing cross-linked polyethylene cables by reacting polyethylene with an organic silane and a free radical saponification compound27.
Add silanol condensation catalyst r to polyethylene, extrude coat it onto the conductor, and pass it through water or a hot water bath for silane crosslinking? The vinyl sheath (B') was extrusion coated in a separate process.

Here, organic silane has the general formula 1-membered L' S h Yz
(几 is a monovalent olefinic unsaturated hydrogen group or a hydrocarboxyl group, Y is a hydrolyzable organic group, R' is a monovalent hydrocarbon group other than an aliphatic unsaturated hydrocarbon group or a group Y
), and R is vinyl,
Allyl, butenyl, cyclohexenyl, 7/lopencdienyl, cyclohexagenyl, OH2=0 (OH3)
000'(O4 included-1at-i2L□(OH3)000
0 remaining oH, 0(cxq, >3-1ai-chi=O(OH
3) 0OOOj120)(200H,0H(OH)O
H,0(OH2)! - etc. are 2J, Y is any hydrolyzable organic group, such as an alkoxy group such as methoxy group, di-toxy group, butoxy group, acyloxy group such as pormyoxy group, acetoxy group, or pro- Pionoxyi, -0N==O(OH,)2, -ow=c (
0H3) O, H,, oximo group such as -ON''O(06Hs)z, alkylamino group such as -NHO,H, etc. Among these, the same group or a different fundamental sound 2 R' is a monovalent hydrocarbon group other than an aliphatic hydrocarbon group, such as methyl, ethyl, proyl, tetradecyl, octadecyl, phenyl, pen/zyl, tolyl, or the same group as Y. be.

Among such silanes, R81Y3 type silane is most preferred, and vinyltriethoxysilane and vinyltrimethoxysilane are particularly preferred. The free radical-generating metal compound is a compound that can generate free radicals in polyethylene oxide under graft reaction conditions and has a half-life at the reaction temperature of 6 minutes or less, preferably 1 minute or less, These include organic peroxides or esters, such as benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl oxide, 2,5-
shi()zo-oxybenzoate)hexyne-3,1.3
-bis(t-butylperoxyimprovil)penze/
, lauroyl peroxide, 1-dityl peracetate, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3,2,5-dimer-2,5-di(t
-butylperoxy) hexa7, t-butylbenzoate, and the like. Also, azo compounds such as azobisinbutyronitrile and dimethylazodiisobutyrate can be used similarly.

Sinnoh Server Catalyst and Organic Metals such as dibutyltin diacetate, dibutyltin diacetate, dibutyltin octoate, lead nanthenate, caprylic zinc, cobalt naphthenate, tetrabutyl titanate Ester, titanium aged tetranonyl ester, lead stearate, zinc stearate, cadmium stearate,
Barium stearate, calcium stearate, etc. are used.

As mentioned above, in the conventional method, a silanol feeding catalyst is added to the sila/grafted polyamide, the extrusion coating is applied onto the conductor, and the sila/grafted polymer is cross-linked by passing it through water or hot water. It takes a long time to immerse in water, and the heat deformation rate of the insulator is also large. Therefore, the vinyl chloride sheath must be coated by extrusion in a separate process.

In order to improve the production efficiency of the cable, the present inventors have found that it is desirable to perform extrusion coating by sheathing/dem extrusion, but as mentioned above, this is not possible with conventional American technology.

In view of this situation, the inventor of the present invention determined that Shira/
By improving the crosslinking method and using water or hot water showers, we can improve the heat deformation rate of the absolute R body, realize tandem extrusion of vinyl chloride sheaths, and efficiently manufacture NFC crosslinked polyethylene cables with high quality. This is what was created.

The present invention will be explained below with reference to the drawings.The first extruder 3, which extrudes silane crosslinked polyethylene through a feeder 1 and a caterpillar traction device 2, has an insulating structure. Extrusion coating.

The compound mentioned here is made by adding a silanol condensation catalyst to syringant polyethylene.
Extrusion coating is carried out using a crosshead die at 160-250°C. The extrusion coated cable core C is vigorously showered with water or hot water shower 4 to effect water crosslinking, and then the polyvinyl chloride concrete gland is passed through a second extruder 5.
The cross-linked polyethylene cable is coated by extrusion and passed through a cooling water tank 6, passed through seven caterpillar traction devices (pulling machines), and then wound into a winding machine 8.

Next, embodiments of the present invention will be described.

Polyethylene (density 0.920 melton roll rate 2.
Of' / 10m1n) For 100Wht part,
Vinyl methoxysila 72 times part, dicumyl no ξ-okitu.

Id 0.05m needle, dibutyltin dilaurate 008N
The first extruder (diameter: 115 mm, L/D = 25 mm) was mixed and kneaded into a conductor with a nominal cross-sectional area of 20 mm.
Extrusion coating was applied to a very thick layer, followed by a hot shower at about 60°C, followed by a second extruder (caliber 150 + o + φ).
, L/D=25) by polyvinyl chloride sheath k 1
．． A cross-linked polyethylene cable was produced by extrusion to a thickness of 7 tar.

Comparative Example 1 Cooling water teky(
Other than that, a cross-linked polyethylene cable of 1 km was manufactured in the same manner as in the Example.

Comparative Example 2 A cross-linked polyethylene cable was produced in the same manner as in Comparative Example 1, except that the extrusion compound machine for cross-linked polyethylene and the extrusion coating for polyvinyl chloride were performed in separate steps.

The results of a comparative test of the physical properties of the crosslinked polyethylene insulators of the crosslinked polyethylene cables obtained by the methods of the above Examples and Comparative Examples are as follows.

Note 1 The heating deformation rate was measured using a cable-shaped sample at 120° C. under a load of 2.5 kt, preheating for 30 minutes, and pressurization for 30 minutes.

Note 2: The tensile test was performed by punching/pulling the insulator using a JI No. 83 tamper and pulling at 500 tm/+nin.

As is clear from the results of this comparative test, the thermal deformation rate of the method of the present invention is much better than that of the comparative example. However, this means that cold and hot water showers are an exceptionally superior method to cold and hot water baths.In particular, cold water showers and C5 hot water showers are more likely to absorb water into polyethylene and sufficiently cause crosslinking reactions, making it possible to realize tandem extrusion. This made it possible.

[Brief explanation of the drawing]

The figure is a schematic explanatory diagram of an embodiment of the present invention. 3... First extruder 4... Water or hot water shower 5
...Second extruder C...Cable core agent Patent attorney Mamoru Takeuchi Procedural amendment (voluntary) March 5, 1980% Commissioner of the License Agency Mr. Kazuo Wakasugi 1, Indication of the case 1988% IfF Application No. 803 2, Name of Invention Method for Manufacturing Cross-Linked Polyethylene Cable 3, Relationship with the Amendment Case Applicant: 5-1 Kiba-chome, Koto-ku, Tokyo (518) Representative: Fujikura Electric Wire Co., Ltd. Makoto Buyetani - 4, Agent: 6, Hisashi Yamiho, 2-15-13 Uchikanda, Chiyoda-ku, Tokyo 101, Japan; Column 7 for detailed explanation of the invention in the specification subject to amendment; Attachment 8 to Tani, 8 of the amendment. Insert the following sentence between lines 4 and 5 of the detailed statement, line 6, 1c. At this time, it is preferable to remove water droplets on the surface of the internal cable core by wiping with a sponge or the like immediately before extruding the vinyl chloride sheath, since foaming will not occur in the vinyl chloride sheath.

Claims (1)

[Claims] A silanol condensation catalyst is added to silanol condensation catalyst to silane-grafted polyethylene, which is reacted with an organic silane and a free radical-forming adduct, and extrusion coated onto a conductor, and water or warm water shower is applied to promote the silane crosslinking reaction. □Then, □Extrusion coating with polyvinyl chloride sheath/Dem has a cross-linking characteristic of 1%? Method for manufacturing polyethylene cable. ″