JPH035004B2 - - Google Patents
Info
- Publication number
- JPH035004B2 JPH035004B2 JP57066999A JP6699982A JPH035004B2 JP H035004 B2 JPH035004 B2 JP H035004B2 JP 57066999 A JP57066999 A JP 57066999A JP 6699982 A JP6699982 A JP 6699982A JP H035004 B2 JPH035004 B2 JP H035004B2
- Authority
- JP
- Japan
- Prior art keywords
- polyethylene
- insulating layer
- density
- cross
- water
- 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.)
- Expired - Lifetime
Links
- 239000004698 Polyethylene Substances 0.000 claims description 12
- -1 polyethylene Polymers 0.000 claims description 12
- 229920000573 polyethylene Polymers 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 10
- 229920003020 cross-linked polyethylene Polymers 0.000 claims description 8
- 239000004703 cross-linked polyethylene Substances 0.000 claims description 8
- 150000001451 organic peroxides Chemical class 0.000 claims description 7
- 239000004020 conductor Substances 0.000 claims description 6
- 239000000155 melt Substances 0.000 claims description 4
- 238000004132 cross linking Methods 0.000 claims description 3
- 240000005572 Syzygium cordatum Species 0.000 description 11
- 235000006650 Syzygium cordatum Nutrition 0.000 description 11
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 5
- 239000003054 catalyst Substances 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 230000006866 deterioration Effects 0.000 description 3
- 238000001125 extrusion Methods 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 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 2
- 239000000654 additive Substances 0.000 description 2
- 239000003963 antioxidant agent Substances 0.000 description 2
- 239000003795 chemical substances by application Substances 0.000 description 2
- 239000011248 coating agent Substances 0.000 description 2
- 238000000576 coating method Methods 0.000 description 2
- 238000013329 compounding Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 125000004185 ester group Chemical group 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 230000002401 inhibitory effect Effects 0.000 description 2
- 239000012212 insulator Substances 0.000 description 2
- 229920001179 medium density polyethylene Polymers 0.000 description 2
- 239000004701 medium-density polyethylene Substances 0.000 description 2
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- XTXRWKRVRITETP-UHFFFAOYSA-N Vinyl acetate Chemical compound CC(=O)OC=C XTXRWKRVRITETP-UHFFFAOYSA-N 0.000 description 1
- 230000000996 additive effect Effects 0.000 description 1
- 229910052783 alkali metal Inorganic materials 0.000 description 1
- 150000001340 alkali metals Chemical class 0.000 description 1
- 230000003078 antioxidant effect Effects 0.000 description 1
- UQLDLKMNUJERMK-UHFFFAOYSA-L di(octadecanoyloxy)lead Chemical compound [Pb+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O UQLDLKMNUJERMK-UHFFFAOYSA-L 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 229920001684 low density polyethylene Polymers 0.000 description 1
- 239000004702 low-density polyethylene Substances 0.000 description 1
- 239000000314 lubricant Substances 0.000 description 1
- 238000004519 manufacturing process Methods 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
- 230000000379 polymerizing effect Effects 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A30/00—Adapting or protecting infrastructure or their operation
- Y02A30/14—Extreme weather resilient electric power supply systems, e.g. strengthening power lines or underground power cables
Landscapes
- Insulated Conductors (AREA)
- Organic Insulating Materials (AREA)
Description
本発明は、架橋ポリエチレンを絶縁体とした電
線ならびにケーブルに関するものである。
架橋ポリエチレンは、絶縁性や耐熱性に優れた
特徴をもつていることから電線ならびにケーブル
の絶縁体として多く用いられてきている。
しかし、近年、浸水状態で課電を行つた場合、
水トリーが発生し、電気的な劣化が進行すること
が認められている。そして、今後も架橋ポリエチ
レンケーブルは地中埋設など浸水環境下における
使用が進むことになるので、水トリーを抑制する
ことが重要な問題となつている。
この問題については、既に各方面で種々の研究
がなされており、その対策として、例えば(1)エチ
レンビニルアセテートコポリマを単独あるいはブ
レンドして用いる方法、(2)特殊な酸化防止剤やエ
ステル基含有添加剤を添加する方法などが提案さ
れている。
しかし、(1)では水トリー抑止効果を向上させる
ためビニルアセテート含有量を多くすると、電気
性が低下する問題がある。また、(2)では水トリー
発生を抑止する効果が十分といえる程優れている
ものがない。
本発明は、上記の状況に鑑みなされたものであ
り、導体を被覆する架橋ポリエチレン絶縁層にお
ける水トリーの発生を抑制でき、もつて絶縁劣化
の進行を阻止できる架橋ポリエチレン絶縁電線な
らびにケーブルの提供を目的とするものである。
本発明の架橋ポリエチレン絶縁電線なやびにケ
ーブルは、高圧法で製造され密度が0.925〜0.935
（ｇ／cm3）の範囲にあり、メルトインデツクスが
0.5以上のポリエチレンに有機過酸化物を添加し
てなる組成物を導体の外周に被覆して絶縁層を形
成し、該絶縁層を架橋してなることを特徴とする
ものである。
本発明において、高圧法で製造され密度が
0.925〜0.935（ｇ／cm3）の範囲にあるホリエチレ
ンとは、低密度ポリエチレンの製造に使用されて
きた高圧法により得られ、密度が中密度の範囲に
あるポリエチレンをいう。すなわち、エチレンを
有機過酸化物を触媒として数千気圧下で重合する
ことにより得られるものであり、イオン性の触媒
残渣が含まれないことから優れと耐水トリー性を
有するものと考えられる。
従来一般に使用されてきている低圧法による中
密度ポリエチレンは、製造過程においてアルカリ
金属触媒が使用され、ポリエチレン中にイオン性
の触媒残渣が多く含まれることになり、これが起
因して十分な耐水トリー性の向上をはかることが
できないものと考えられる。
本発明において、密度を0.925〜0.935（ｇ／cm3）
の範囲に限定したのは、この下限値以下では水ト
リーの発生を抑止する効果がなく、この上限値を
越えるものは実際上合成が困難なためである。
また、メルトインデツクスを0.5以上と限定し
た理由は、0.5以下では押出成形、特に有機過酸
化物を添加して押し出しする場合にスコーチを発
生し、押出が円滑にできないためである。上限は
特に限定しないが、あまり大きすぎると架橋度の
低下などが起きるため、10位までが望ましい。
本発明では、上記ポリエチレンにジクミルパー
オキサイドに代表される有機過酸化物を添加して
なる組成物でもつて絶縁層を形成し、該絶縁層は
加熱により架橋される。
なお、本発明においては、ポリエチレンおよび
有機過酸化物に加えて適宜酸化防止剤、滑剤など
の配合剤を添加することが可能である。さらに水
トリーを防止する配合剤、例えば、極性基を有す
るポリマをブレンドしたり、エステル基含有添加
剤を添加することにより一段と耐水トリー性を向
上できる。
以下、本発明を実施例に基づいて詳細に説明す
る。
添付図面は、本発明ケーブルの一実施例の断面
説明図であり、１は導体、２は半導電層、３は絶
縁層である。
絶縁層３は、第１表の実施例および比較例に示
す各種ポリエチレンを用い、ポリエチレン100重
量部に対してジクミルパーオキサイド2.5重量部
および４，4′−チオビス（６−ターシヤリブチル
−３−メチルフエノール）0.2重量部を添加した
組成物を半導電層２の外周に押出被覆し、過熱架
橋して形成した。このとき、半導電層２の外径は
４mm、絶縁層３の外径は８mmとなるようにした。
なお、実施
The present invention relates to electric wires and cables using crosslinked polyethylene as an insulator. Cross-linked polyethylene has been widely used as an insulator for electric wires and cables because it has excellent insulation properties and heat resistance. However, in recent years, when charging electricity in flooded conditions,
It is recognized that water tree occurs and electrical deterioration progresses. In the future, cross-linked polyethylene cables will continue to be used in flooded environments, such as when buried underground, so controlling water trees has become an important issue. Various studies have already been carried out in various fields regarding this problem, and as countermeasures, for example, (1) methods using ethylene vinyl acetate copolymers alone or in combination, (2) methods containing special antioxidants or ester groups. A method of adding additives has been proposed. However, in (1), when the vinyl acetate content is increased in order to improve the water tree inhibiting effect, there is a problem that the electrical property decreases. Furthermore, in (2), there is no product that is sufficiently effective in inhibiting water tree generation. The present invention has been made in view of the above-mentioned circumstances, and aims to provide cross-linked polyethylene insulated wires and cables that can suppress the occurrence of water trees in the cross-linked polyethylene insulating layer covering the conductor, thereby preventing the progress of insulation deterioration. This is the purpose. The cross-linked polyethylene insulated wire cable of the present invention is manufactured by a high voltage method and has a density of 0.925 to 0.935.
(g/cm 3 ), and the melt index is
It is characterized in that an insulating layer is formed by coating the outer periphery of a conductor with a composition made by adding an organic peroxide to polyethylene having a molecular weight of 0.5 or more, and the insulating layer is crosslinked. In the present invention, the density is
Polyethylene in the range of 0.925 to 0.935 (g/cm 3 ) refers to polyethylene that is obtained by the high-pressure method used for producing low-density polyethylene and has a density in the medium density range. That is, it is obtained by polymerizing ethylene under several thousand atmospheric pressures using an organic peroxide as a catalyst, and is considered to have excellent water resistance because it does not contain ionic catalyst residues. Medium-density polyethylene manufactured by the low-pressure method that has been commonly used in the past uses an alkali metal catalyst in the manufacturing process, and the polyethylene contains a large amount of ionic catalyst residue, which results in insufficient water resistance. It is considered that it is not possible to improve the In the present invention, the density is 0.925 to 0.935 (g/cm 3 ).
The reason for limiting the range is that below this lower limit, there is no effect of suppressing the occurrence of water trees, and that exceeding this upper limit is practically difficult to synthesize. Further, the reason why the melt index is limited to 0.5 or more is that if it is 0.5 or less, scorch will occur during extrusion molding, especially when extruding with addition of an organic peroxide, and extrusion cannot be performed smoothly. The upper limit is not particularly limited, but if it is too large, the degree of crosslinking will decrease, so it is preferably up to the 10th position. In the present invention, an insulating layer is formed using a composition obtained by adding an organic peroxide such as dicumyl peroxide to the above polyethylene, and the insulating layer is crosslinked by heating. In addition, in the present invention, in addition to polyethylene and the organic peroxide, it is possible to appropriately add compounding agents such as an antioxidant and a lubricant. Furthermore, the water tree resistance can be further improved by blending a compounding agent that prevents water tree, for example, a polymer having a polar group or adding an additive containing an ester group. Hereinafter, the present invention will be explained in detail based on examples. The attached drawing is an explanatory cross-sectional view of one embodiment of the cable of the present invention, in which 1 is a conductor, 2 is a semiconducting layer, and 3 is an insulating layer. For the insulating layer 3, various polyethylenes shown in the Examples and Comparative Examples in Table 1 were used, and 2.5 parts by weight of dicumyl peroxide and 4,4'-thiobis(6-tertiarybutyl-3) were used per 100 parts by weight of polyethylene. - methylphenol) was extrusion coated on the outer periphery of the semiconductive layer 2, and crosslinked by heating. At this time, the outer diameter of the semiconductive layer 2 was 4 mm, and the outer diameter of the insulating layer 3 was 8 mm.
In addition, implementation
【表】
例３のみはステアリン酸鉛を0.2重量部添加した
組成物を使用した。
上記のようにして製造したケーブルを水中に浸
漬し、50Hz、3kVの電圧を18カ月課電し、水トリ
ー発生状況を試験した結果を第２表に示す。[Table] Only in Example 3, a composition to which 0.2 parts by weight of lead stearate was added was used. The cable manufactured as described above was immersed in water and a voltage of 50 Hz and 3 kV was applied for 18 months to test the occurrence of water trees. The results are shown in Table 2.
【表】
第２表から明らかなように、実施例１、２、３
では水トリー発生抑止効果は著しく大きい。これ
に対し、比較例１は高圧法で製造しても密度が
0.920と小さいポリエチレンを用いた場合であり、
比較例２および３は低圧法によつて得られた中密
度ポリエチレンを用いた場合であり、いずれも水
トリーが著しく発生している。
以上のように、本発明は、絶縁層を形成するポ
リエチレンと水トリーの関連を追求し、高圧法で
製造され密度が0.925〜0.935（ｇ／cm3）の範囲に
あり、メルトインデツクスが0.5以上のポリエチ
レンに有機過酸化物を添加してなる組成物を導体
外周に被覆して絶縁層を形成し、該絶縁層を架橋
してなることにより耐水トリー性を著しく向上
し、絶縁性の絶縁劣化の進行を阻止できる架橋ポ
リエチレン絶縁電線ならびにケーブルを実現でき
るようになる。[Table] As is clear from Table 2, Examples 1, 2, and 3
In this case, the effect of preventing water tree occurrence is extremely large. On the other hand, in Comparative Example 1, the density was low even when manufactured using the high pressure method.
When using polyethylene as small as 0.920,
Comparative Examples 2 and 3 are cases in which medium-density polyethylene obtained by a low-pressure method is used, and in both cases, water treeing occurs significantly. As described above, the present invention pursues the relationship between polyethylene forming an insulating layer and water tree, and is produced by a high-pressure method, has a density in the range of 0.925 to 0.935 (g/cm 3 ), and has a melt index of 0.5. By coating the outer periphery of the conductor with a composition made by adding an organic peroxide to the polyethylene described above to form an insulating layer, and crosslinking the insulating layer, the water resistance is significantly improved and the insulating insulation is It becomes possible to realize cross-linked polyethylene insulated wires and cables that can prevent the progress of deterioration.
添付図面は、本発明ケーブルの一実施例の横断
面説明図である。
１：導体、２：半導電層、３：絶縁層。
The attached drawing is an explanatory cross-sectional view of one embodiment of the cable of the present invention. 1: conductor, 2: semiconducting layer, 3: insulating layer.
Claims (1)
cm3）の範囲にあり、メルトインデツクスが0.5以
上のポリエチレンに有機過酸化物を添加してなる
組成物を導体の外周に被覆して絶縁層を形成し、
該絶縁層を架橋してなることを特徴とする架橋ポ
リエチレン絶縁電線ならびにケーブル。1 Manufactured using a high pressure method and has a density of 0.925 to 0.935 (g/
cm 3 ) and has a melt index of 0.5 or more, a composition made by adding an organic peroxide to polyethylene is coated on the outer periphery of the conductor to form an insulating layer,
Cross-linked polyethylene insulated wires and cables, characterized in that they are formed by cross-linking the insulating layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57066999A JPS58184206A (en) | 1982-04-21 | 1982-04-21 | Wire and cable |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP57066999A JPS58184206A (en) | 1982-04-21 | 1982-04-21 | Wire and cable |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58184206A JPS58184206A (en) | 1983-10-27 |
| JPH035004B2 true JPH035004B2 (en) | 1991-01-24 |
Family
ID=13332207
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP57066999A Granted JPS58184206A (en) | 1982-04-21 | 1982-04-21 | Wire and cable |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58184206A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60198006A (en) * | 1984-03-21 | 1985-10-07 | 日立電線株式会社 | Method of producing wire and cable |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5070881A (en) * | 1973-10-29 | 1975-06-12 |
-
1982
- 1982-04-21 JP JP57066999A patent/JPS58184206A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5070881A (en) * | 1973-10-29 | 1975-06-12 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58184206A (en) | 1983-10-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP5907015B2 (en) | Railway vehicle wires and railway vehicle cables | |
| JP3989306B2 (en) | Water crosslinkable resin composition excellent in tracking resistance and weather resistance, and power cable having an insulating coating layer comprising the same | |
| JPH035004B2 (en) | ||
| KR100874596B1 (en) | Fabricating method for hffr(halogen free flame retardent) cable and compounds of the same | |
| US5773145A (en) | Power cable | |
| JP3289424B2 (en) | Polyolefin insulated wire | |
| US4369331A (en) | Ethylene polymer compositions stabilized against water treeing by an organic titanate; and the use thereof as insulation about electrical conductors | |
| JP2560679B2 (en) | Flame retardant electrical insulation composition | |
| JP2001266650A (en) | Electric insulating composition and electric cable | |
| JP2814715B2 (en) | Electric wires and cables | |
| JPS5851415A (en) | Flame resistant insulated wire | |
| JPS58220304A (en) | Electrically insulating composition and wire, cable coated with same composition | |
| JPH03276515A (en) | Water-tree resisting electric wire and cable | |
| JPH0126128B2 (en) | ||
| JP2774571B2 (en) | Electrical cable connection insulator | |
| JPH0452563B2 (en) | ||
| JPS6356645B2 (en) | ||
| JPS6245643B2 (en) | ||
| JP2666543B2 (en) | Electric wires and cables | |
| JPH0234734Y2 (en) | ||
| JPH0314054B2 (en) | ||
| JPH03122908A (en) | Electrically insulated cable | |
| JPH07296649A (en) | Nonhalogen flame resisting insulated wire | |
| JPS586241B2 (en) | plastic insulated wire | |
| JPH08199013A (en) | Semiconductive resin composition and crosslinked polyethylene insulated power cable |