JPH02267814A - Cross-linked polyolefin insulating power cable - Google Patents
Cross-linked polyolefin insulating power cableInfo
- Publication number
- JPH02267814A JPH02267814A JP8703489A JP8703489A JPH02267814A JP H02267814 A JPH02267814 A JP H02267814A JP 8703489 A JP8703489 A JP 8703489A JP 8703489 A JP8703489 A JP 8703489A JP H02267814 A JPH02267814 A JP H02267814A
- Authority
- JP
- Japan
- Prior art keywords
- insulating layer
- layer
- cross
- insulating
- power cable
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229920000098 polyolefin Polymers 0.000 title claims abstract description 24
- 239000004020 conductor Substances 0.000 claims abstract description 8
- -1 polyethylene Polymers 0.000 claims abstract description 8
- 229920001038 ethylene copolymer Polymers 0.000 claims abstract description 6
- 239000004698 Polyethylene Substances 0.000 claims abstract description 5
- 229920000573 polyethylene Polymers 0.000 claims abstract description 5
- 239000000203 mixture Substances 0.000 claims description 4
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 11
- 240000005572 Syzygium cordatum Species 0.000 abstract description 9
- 235000006650 Syzygium cordatum Nutrition 0.000 abstract description 9
- 238000004132 cross linking Methods 0.000 abstract description 5
- 230000015556 catabolic process Effects 0.000 abstract description 4
- 230000015572 biosynthetic process Effects 0.000 abstract description 3
- 229920003020 cross-linked polyethylene Polymers 0.000 abstract description 2
- 239000004703 cross-linked polyethylene Substances 0.000 abstract description 2
- 238000010438 heat treatment Methods 0.000 abstract description 2
- 239000002131 composite material Substances 0.000 abstract 2
- 239000000805 composite resin Substances 0.000 abstract 1
- 239000003431 cross linking reagent Substances 0.000 description 7
- 230000006866 deterioration Effects 0.000 description 7
- 229920005989 resin Polymers 0.000 description 5
- 239000011347 resin Substances 0.000 description 5
- XMNIXWIUMCBBBL-UHFFFAOYSA-N 2-(2-phenylpropan-2-ylperoxy)propan-2-ylbenzene Chemical compound C=1C=CC=CC=1C(C)(C)OOC(C)(C)C1=CC=CC=C1 XMNIXWIUMCBBBL-UHFFFAOYSA-N 0.000 description 4
- 150000008062 acetophenones Chemical class 0.000 description 3
- XYLMUPLGERFSHI-UHFFFAOYSA-N alpha-Methylstyrene Chemical compound CC(=C)C1=CC=CC=C1 XYLMUPLGERFSHI-UHFFFAOYSA-N 0.000 description 3
- 238000010276 construction Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000011342 resin composition Substances 0.000 description 3
- XOUQAVYLRNOXDO-UHFFFAOYSA-N 2-tert-butyl-5-methylphenol Chemical compound CC1=CC=C(C(C)(C)C)C(O)=C1 XOUQAVYLRNOXDO-UHFFFAOYSA-N 0.000 description 2
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 2
- KWOLFJPFCHCOCG-UHFFFAOYSA-N Acetophenone Chemical compound CC(=O)C1=CC=CC=C1 KWOLFJPFCHCOCG-UHFFFAOYSA-N 0.000 description 2
- 229920000181 Ethylene propylene rubber Polymers 0.000 description 2
- DKGAVHZHDRPRBM-UHFFFAOYSA-N Tert-Butanol Chemical compound CC(C)(C)O DKGAVHZHDRPRBM-UHFFFAOYSA-N 0.000 description 2
- 239000003963 antioxidant agent Substances 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 229920001577 copolymer Polymers 0.000 description 2
- 238000000354 decomposition reaction Methods 0.000 description 2
- 239000005038 ethylene vinyl acetate Substances 0.000 description 2
- 238000001125 extrusion Methods 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- WYTRYIUQUDTGSX-UHFFFAOYSA-N 1-phenylpropan-2-ol Chemical compound CC(O)CC1=CC=CC=C1 WYTRYIUQUDTGSX-UHFFFAOYSA-N 0.000 description 1
- BDCFWIDZNLCTMF-UHFFFAOYSA-N 2-phenylpropan-2-ol Chemical compound CC(C)(O)C1=CC=CC=C1 BDCFWIDZNLCTMF-UHFFFAOYSA-N 0.000 description 1
- IYCLKOCAGPKZGF-UHFFFAOYSA-N 2-tert-butylperoxy-1-propan-2-yl-3-prop-1-en-2-ylbenzene Chemical compound C(C)(C)(C)OOC1=C(C=CC=C1C(=C)C)C(C)C IYCLKOCAGPKZGF-UHFFFAOYSA-N 0.000 description 1
- OIGWAXDAPKFNCQ-UHFFFAOYSA-N 4-isopropylbenzyl alcohol Chemical group CC(C)C1=CC=C(CO)C=C1 OIGWAXDAPKFNCQ-UHFFFAOYSA-N 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 238000003776 cleavage reaction Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000007872 degassing Methods 0.000 description 1
- SWXVUIWOUIDPGS-UHFFFAOYSA-N diacetone alcohol Natural products CC(=O)CC(C)(C)O SWXVUIWOUIDPGS-UHFFFAOYSA-N 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000005684 electric field Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229920006228 ethylene acrylate copolymer Polymers 0.000 description 1
- 238000007765 extrusion coating Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- ZONYXWQDUYMKFB-UHFFFAOYSA-N flavanone Chemical compound O1C2=CC=CC=C2C(=O)CC1C1=CC=CC=C1 ZONYXWQDUYMKFB-UHFFFAOYSA-N 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229920001200 poly(ethylene-vinyl acetate) Polymers 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 230000007017 scission Effects 0.000 description 1
- 230000002459 sustained effect Effects 0.000 description 1
Landscapes
- Organic Insulating Materials (AREA)
Abstract
Description
【発明の詳細な説明】
(産業上の利用分野)
本発明は、水トリーの発生が抑制され絶縁劣化の少ない
絶縁層を有する架橋ポリオレフィン絶縁電力ケーブルに
関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a crosslinked polyolefin insulated power cable having an insulating layer that suppresses the occurrence of water trees and exhibits little insulation deterioration.
(従来の技術)
電力送電用の架橋ポリオレフィン絶縁電力ケーブルは、
一般に、導体とこの導体の上に内部半導電層、絶縁層、
外部半導電層をこの順序で形成し、更にその上に金属遮
蔽層、シース層を形成した構造になっている。(Prior technology) Cross-linked polyolefin insulated power cables for power transmission are
Generally, a conductor and an internal semiconducting layer, an insulating layer,
The structure is such that the outer semiconducting layer is formed in this order, and a metal shielding layer and a sheath layer are further formed thereon.
電カケープルのうち、絶縁層が架橋ポリオレフィンから
成るものの場合には、その絶縁層は、通常、ポリオレフ
ィンと架橋剤と必要に応じて抗酸化剤とから構成されて
いる。Among electric cables, when the insulating layer is made of crosslinked polyolefin, the insulating layer is usually composed of polyolefin, a crosslinking agent, and, if necessary, an antioxidant.
この場合、ポリオレフィンとしては、ポリエチレン;ポ
リエチレン−エチレンビニルアセテート系共重合体、エ
チレン−スチレン系共重合体、エチレン−プロピレンゴ
ムのようなエチレン共重合体が使用され、また、架橋剤
としては、通常、ジクミルパーオキサイド(DCP)が
使用されている。そして、導体上にこの架橋ポリオレフ
ィンの絶縁層を形成するときの架橋処理時に、前記DC
Pは分解してアセトフェノン、2−フェニル−2プロパ
ツール、α−メチルスチレンを生成する。In this case, the polyolefin used is polyethylene; an ethylene copolymer such as polyethylene-ethylene vinyl acetate copolymer, ethylene-styrene copolymer, or ethylene-propylene rubber, and the crosslinking agent is usually , dicumyl peroxide (DCP) is used. The DC
P decomposes to produce acetophenone, 2-phenyl-2propanol, and α-methylstyrene.
そしてこれら生成物は、絶縁層や内・外部半導電層に含
有された状態で、製造された電力ケーブルに存在してい
る。These products are present in manufactured power cables as being contained in insulating layers and inner and outer semiconducting layers.
(発明が解決しようとする課題)
ところで、上記した架橋ポリオレフィン絶縁電力ケーブ
ルを長距離に亘り運転する場合には、適当な中間地点で
、それぞれを接続することが必要になる。(Problems to be Solved by the Invention) By the way, when the above-described crosslinked polyolefin insulated power cables are operated over long distances, it is necessary to connect them at appropriate intermediate points.
この中間接続部の1つとして、押出モールドジヨイント
(EMJ)がある。そしてこのEMJ施工時には、絶縁
層と内・外部半導電層はいずれも、180〜250°C
という温度に加熱される。One of these intermediate connections is an extrusion mold joint (EMJ). During EMJ construction, the temperature of both the insulating layer and the inner and outer semiconducting layers is 180 to 250°C.
is heated to a temperature of
一方、前記したように、絶縁層や内・外部半導電層に含
有されている2−フェニル−2−プロパツールは、約1
40’C以上の温度になると、α−メチルスチレンと水
に分解する。On the other hand, as mentioned above, the 2-phenyl-2-propertool contained in the insulating layer and the inner and outer semiconducting layers is about 1
At temperatures above 40'C, it decomposes into α-methylstyrene and water.
それゆえ、従来の架橋ポリオレフィン絶縁電力ケーブル
にEMJ施工を行なった場合には、絶縁層と内・外部半
導電層の含水量が増加することになる。Therefore, when EMJ is applied to a conventional crosslinked polyolefin insulated power cable, the water content of the insulating layer and the inner and outer semiconducting layers increases.
一般に、同一絶縁材料において、その含水量が増加する
とそれに伴なって水トリーが発生し、その数、大きさも
増大するということが知られている。そして、架橋ポリ
オレフィン絶縁電力ケーブルにおいても、その特徴的な
劣化形態として水トリー劣化が知られており、この水ト
リーの発生・進展がケーブルの絶縁破壊特性に大きな影
響を与えている。Generally, it is known that in the same insulating material, as the water content increases, water trees occur, and their number and size also increase. Water tree deterioration is also known as a characteristic form of deterioration in crosslinked polyolefin insulated power cables, and the occurrence and progression of this water tree has a great influence on the dielectric breakdown characteristics of the cable.
したがって、従来の架橋ポリオレフィン絶縁電力ケーブ
ルにおいては、架橋剤がDCPであることにより、E、
MJ等を施したときに、施工条件によっては絶縁層と内
・外部半導電層の含水量が増加し、水トリー劣化が生じ
るという問題が避は得ない状態であった。Therefore, in conventional crosslinked polyolefin insulated power cables, since the crosslinking agent is DCP, E,
When applying MJ etc., depending on the construction conditions, the water content of the insulating layer and the inner and outer semiconducting layers increases, resulting in an unavoidable problem of water tree deterioration.
本発明は架橋ポリオレフィン絶縁電力ケーブルにおける
上記問題を解決し、水トリーの発生が抑制され絶縁劣化
の少ない絶縁層を有する電カケープルの提供を目的とす
る。The present invention solves the above-mentioned problems in crosslinked polyolefin insulated power cables, and aims to provide a power cable having an insulating layer that suppresses the occurrence of water trees and reduces insulation deterioration.
(発明が解決しようとする課題)
上記した目的を達成するために、本発明においては、導
体上に内部半導電層、絶縁層、外部半導電層がこの順序
で形成されている架橋ポリオレフィン絶縁電力ケーブル
において、前記絶縁層が、ポリエチレンまたは/および
エチレン共重合体100ffi!部と1 (2Te
rt−ブチルパーオキシイソプロピル)−3−イソプロ
ペニルベンゼン0.5〜10重量部とを必須成分とする
架橋性ポリオレフィン組成物から形成されて成ることを
特徴とする架橋ポリオレフィン絶縁電力ケーブルが提供
される。(Problems to be Solved by the Invention) In order to achieve the above-mentioned object, the present invention provides a crosslinked polyolefin insulated power supply in which an inner semiconducting layer, an insulating layer, and an outer semiconducting layer are formed on a conductor in this order. In the cable, the insulating layer is made of polyethylene or/and ethylene copolymer 100ffi! Part and 1 (2Te
Provided is a crosslinked polyolefin insulated power cable characterized in that it is formed from a crosslinkable polyolefin composition containing as an essential component 0.5 to 10 parts by weight of rt-butylperoxyisopropyl)-3-isopropenylbenzene. .
本発明の架橋ポリオレフィン絶縁電力ケーブルは、その
絶縁層が後述する架橋ポリオレフィンであることに最大
の特徴を有するものであって、他の要素は従来の場合と
変わることはない。The crosslinked polyolefin insulated power cable of the present invention has the greatest feature in that its insulating layer is made of crosslinked polyolefin, which will be described later, and other elements remain the same as in the conventional case.
絶縁層を構成する架橋ポリオレフィンは、ベース樹脂で
あるポリエチレンまたは/およびエチレン共重合体と、
架橋剤である’l −(2−Tert−ブチルパーオキ
シイソプロピル)−3−イソプロペニルベンゼンを必須
成分とする。The crosslinked polyolefin constituting the insulating layer is made of polyethylene or/and ethylene copolymer as a base resin,
The crosslinking agent 'l-(2-Tert-butylperoxyisopropyl)-3-isopropenylbenzene is an essential component.
ここで、エチレン共重合体としては、従来の場合と同様
のものであればよく、具体的には、エチレン−エチレン
アクリレート系共重合体、エチレン−ビニルアセテート
系共重合体、エチレン−スチレン系共重合体、エチレン
−プロピレンゴムをあげることができる。Here, the ethylene copolymer may be the same as in the conventional case, and specifically, ethylene-ethylene acrylate copolymer, ethylene-vinyl acetate copolymer, ethylene-styrene copolymer, etc. Examples include polymers and ethylene-propylene rubber.
架橋剤は、1 (2Tert−ブチルパーオキシイ
ソプロピル)−3−イソプロペニルベンゼンである。こ
の化合物は架橋処理時の分解においてDCPのように2
−フェニル−2−プロパツールを生成しない。分解時の
主生成物は、アセトンとtブチルアルコールである。し
かしこれらの主生成物はいずれも沸点が低いため、架橋
処理時および後段におけるケーブルのガス抜き工程時に
、絶縁層から容易に系外に散逸せしめることができる。The crosslinking agent is 1 (2Tert-butylperoxyisopropyl)-3-isopropenylbenzene. This compound, like DCP, decomposes during the crosslinking process.
-Does not produce phenyl-2-propanol. The main products during decomposition are acetone and t-butyl alcohol. However, since these main products all have low boiling points, they can be easily dissipated from the insulating layer to the outside of the system during the crosslinking process and the subsequent cable degassing process.
このように、この架橋剤は2−フェニル−2=プロパツ
ールを生成しないので、E M J 施工時ニ、クミル
アルコールの分解に伴なう絶縁層の含水量増加は起らず
、水トリーの発生・進展、更にそれに基づく絶縁破壊特
性の低下は抑制される。In this way, since this crosslinking agent does not generate 2-phenyl-2=propertool, the water content of the insulating layer does not increase due to the decomposition of cumyl alcohol during EMJ construction, and water treatment does not occur. The occurrence and progress of this, as well as the resulting deterioration of dielectric breakdown characteristics, are suppressed.
のようなアセトフェノン誘導体を生成する。そしてこの
アセトフェノン誘導体は二重結合が開裂することにより
ベース樹脂であるポリオレフィンにグラフト結合してそ
の骨格に保持されるため、得られた電カケープルにおい
ては、アセトフェノン誘導体による電界緩和効果が長期
に亘って持続されるという効果が発現する。produces acetophenone derivatives such as This acetophenone derivative is graft-bonded to the base resin polyolefin by cleavage of the double bond and is retained in its skeleton, so that in the obtained electric capule, the electric field relaxation effect of the acetophenone derivative lasts for a long time. The effect is sustained.
この化合物は、前記したベース樹脂100重量部に対し
、0.5〜10重量部配合される。配合量が0.5重量
部未満の場合は、ベース樹脂中への均一分散が困難とな
り、また10重量部を超えると絶縁層形成時における押
出加工性が低下するからである。好ましい配合量は、ベ
ース樹脂100重量部に対し、1.5〜4重量部である
。This compound is blended in an amount of 0.5 to 10 parts by weight with respect to 100 parts by weight of the above-mentioned base resin. If the amount is less than 0.5 parts by weight, uniform dispersion into the base resin will be difficult, and if it exceeds 10 parts by weight, extrusion processability during the formation of the insulating layer will deteriorate. The preferred blending amount is 1.5 to 4 parts by weight based on 100 parts by weight of the base resin.
絶縁層になる樹脂組成物は上記組成をもって必須とする
が、更に必要に応じて、公知の抗酸化剤、滑剤、充填剤
などを適量配合しても不都合ではない。Although the resin composition forming the insulating layer is essential to have the above composition, it is not inconvenient to further include appropriate amounts of known antioxidants, lubricants, fillers, etc., if necessary.
架橋処理は、従来と同じように、導体上に上記樹脂組成
物を押出被覆し、更にそれに、圧力10kg/d、温度
200〜300 ’Cのような処理を施せばよい。The crosslinking treatment may be carried out by extrusion coating the above-mentioned resin composition on the conductor, and then subjecting it to a treatment such as a pressure of 10 kg/d and a temperature of 200 to 300'C, as in the conventional method.
(発明の実施例)
除し例1〜3.比較例1. 2
導体上に、第1表で示した組成の樹脂組成物の内部半導
iJ層、絶縁層、外部半導電層を順次押出被覆し、6K
V、38mm”の各種架橋ポリエチレン絶縁電カケープ
ルを製造した。(Embodiments of the invention) Reduction examples 1 to 3. Comparative example 1. 2. On the conductor, an inner semiconducting iJ layer, an insulating layer, and an outer semiconducting layer of a resin composition having the composition shown in Table 1 were sequentially extruded and coated, and the conductor was heated at 6K.
Various crosslinked polyethylene insulated cables with a diameter of 38 mm were manufactured.
得られた電カケープルの絶縁層を切出し、その含水量W
o (ppm)を測定した。更に、各絶縁層を温度19
0 ’Cで2時間プレスしながら加熱し、加熱直後(5
分以内)における含水IW(p p m)をカールフィ
ッシャー法で測定した。V/ −W oを発生水分量と
して算出した。以上の結果を一括して第1表に示した。The insulating layer of the obtained electric cable was cut out, and its water content W
o (ppm) was measured. Furthermore, each insulating layer is heated to a temperature of 19
Heat while pressing at 0'C for 2 hours, then immediately after heating (5
The water-containing IW (ppm) was measured by the Karl Fischer method. V/-W o was calculated as the amount of water generated. The above results are collectively shown in Table 1.
(以下余白)
第1表
(発明の効果)
以上の説明で明らかなように、本発明の架橋ポリオレフ
ィン絶縁電カケープルは、その絶縁層の架橋剤として、
1−(2−Tert−ブチルパーオキシイソプロビル)
−3−イソプロペニルベンゼンを用いているので、加熱
環境下においては、絶縁層の含水量は少なくなり、その
結果、絶縁層における水トリーの発生・進展は抑制され
、絶縁破壊特性の低下が抑制されることになり、その工
業的価値は極めて大である。(The following is a blank space) Table 1 (Effects of the Invention) As is clear from the above explanation, the crosslinked polyolefin insulating capeple of the present invention has the following as a crosslinking agent for its insulating layer:
1-(2-Tert-butylperoxyisopropyl)
- Since 3-isopropenylbenzene is used, the water content of the insulating layer is reduced in a heated environment, and as a result, the occurrence and progression of water trees in the insulating layer is suppressed, and the deterioration of dielectric breakdown characteristics is suppressed. Therefore, its industrial value is extremely large.
*1 :
4.4 −チオビス(3−メチル−6−Tert−ブチ
ルフェノール)*1: 4.4-thiobis(3-methyl-6-tert-butylphenol)
Claims (1)
序で形成されている架橋ポリオレフィン絶縁電力ケーブ
ルにおいて、前記絶縁層が、ポリエチレンまたは/およ
びエチレン共重合体100重量部と1−(2−Tert
−ブチルパーオキシイソプロピル)−3−イソプロペニ
ルベンゼン0.5〜10重量部とを必須成分とする架橋
性ポリオレフィン組成物から形成されて成ることを特徴
とする架橋ポリオレフィン絶縁電力ケーブル。In a crosslinked polyolefin insulated power cable in which an inner semiconducting layer, an insulating layer, and an outer semiconducting layer are formed in this order on a conductor, the insulating layer comprises 100 parts by weight of polyethylene or/and an ethylene copolymer and 1-( 2-Tert
1. A crosslinked polyolefin insulated power cable, characterized in that it is formed from a crosslinkable polyolefin composition containing 0.5 to 10 parts by weight of -butylperoxyisopropyl)-3-isopropenylbenzene as an essential component.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8703489A JPH02267814A (en) | 1989-04-07 | 1989-04-07 | Cross-linked polyolefin insulating power cable |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8703489A JPH02267814A (en) | 1989-04-07 | 1989-04-07 | Cross-linked polyolefin insulating power cable |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH02267814A true JPH02267814A (en) | 1990-11-01 |
Family
ID=13903666
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP8703489A Pending JPH02267814A (en) | 1989-04-07 | 1989-04-07 | Cross-linked polyolefin insulating power cable |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH02267814A (en) |
-
1989
- 1989-04-07 JP JP8703489A patent/JPH02267814A/en active Pending
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