DE1640160B2 - INSULATED ELECTRIC CONDUCTOR - Google Patents

Description

The ethylene polymer can also be used as a common antioxidant contained in an amount up to a few percent. Preferred antioxidants are polymeric Reaction products from acetone and aniline or from acetone and diphenylamine, especially poly-S renized trimethyldihydroquinolines.

The ethylene polymer can optionally also fillers, dyes, plasticizers, stabilizers, Dispersant ii. Like. In the usual amounts contain.

The ethylene polymer layer is applied to the single-core or multi-core electrical conductor made of, for example, copper. Aluminum or steel, optionally provided with a removable material, in particular paper, applied and crosslinked in the usual way. A fibrous inorganic layer of rock wool, glass wool, asbestos and the like is then applied to the ethylene polymer layer. Asbestos is preferably used in woven or non-woven form. The fibrous inorganic layer is impregnated with a heat-resistant halogenated fourth polymer. It is preferred to use chlorinated polymers with a chlorine content of preferably 30 to 70 percent by weight. The halogenated polymers may Polymerization be manufactured by Halogenmonomeren or halogenation of natural or synthetic polymers either duich, have a molecular weight of about 5000 to show thermoplastic behavior and in conjunction with the fibrous inorganic layer such a heat resistance that it does not at 15O ⁰ C or melt and are not yet decomposed.

One group of suitable halogenated polymers are the polyvinyl halides, including polymers of Vinyl chloride, vinyl dichloride and / or vinylidene chloride and mixed polymers of a vinyl halide and suitable monomers.

Another group of suitable halogenated polymers are halogenated, especially chlorinated olefin polymers, for example chlorinated polymers of ethylene, propylene, butene-1, isobutylene, pentene-1 and the like, as well as copolymers of one or more olefins and other suitable monomers. Preferably the halogenated polymers and mixed polymers used should have a molecular weight of at least Own 5000 to 6000.

Furthermore are 7tir impregnation of the fibrous inorganic Layer of halogenated natural rubber or synthetic rubber suitable. Preferably used one chlorinated rubber. si

The heat-resistant thermoplastic used to impregnate the fibrous inorganic layer In the usual way, polymers can contain fillers, dyes, plasticizers, antioxidants, Contain stabilizers, dispersants and the like. To impregnate the fibrous layer, the halogenated polymers either melted or dissolved in a suitable solvent.

The invention will now be explained in more detail using an example.

A typical crosslinkable composition for producing the ethylene polymer layer consists of 68.69 percent by weight Polyethylene, 1.37 percent by weight of polymerized 1,2-dihydro-2,2,4-trimethylquinoline as Antioxidant, 2.44% dicumyl peroxide and 27.50% by weight of finely divided carbon as Filler.

Based on the polyethylene, up to 2 percent by weight of antioxidant, 1 to 10 weight percent of dicumyl peroxide and up to 100 ° / _0, preferably 20 to 3O ° / o filler be provided.

The crosslinkable mass is applied in the usual way in a thickness of about 0.5 mm and then through in the usual way Application of heat networked. The crosslinked ethylene polymer layer is then covered with an asbestos layer, expediently by means of a card. The asbestos layer is then impregnated with a 10 ° / ₀ solution of chlorinated rubber having a chlorine content of about 55 percent by weight in a solvent of toluene and xylene. Solutions with a polymer content of 8 to 20 percent by weight can also be used. After the impregnation, the solvent is driven off in a suitable manner, for example by passing the impregnated conductor through an oven.

Comparative tests were carried out to demonstrate the excellent properties of a conductor according to the invention. In Table I below the structure of various conductor samples examined can be seen. Sample 1 is a commercially available ladder. Samples 2 to 6 were in the manner explained in the example with a Insulation made of cross-linked polyethylene. Samples 2, 4 and 6 were also used in the im Example explained way provided with an impregnated asbestos layer.

Table I.

sample

AWO no

Strand division

Paper release liner, mm

Polyethylene insulation, mm

Impregnated ashest layer, mm ...

16
26/010

0.7 *

16

19 / 0117T 0.05 0.5 0.3 16

19 / 0117T
0.05
0.5

19/0117 ß
0.05
0.5
0.3

16

19 / 0117B
0.05
0.5

18th

19/0092
0.05
0.5
0.3

*) Sample 1 has an acetyl cellulose treadle layer and was provided with a hot, molten impregnation agent.

Table II shows physical properties of samples 2 and 4 according to the invention after heat aging in an oven at 158 ^° C. in comparison to samples 3 and 5 without an impregnated asbestos layer,

Table 11 Heat aging in an air oven at 158 ° C

Originally 2 5 7th 10 Days
15th 30th 45 60 90 156 146 150 108 102 34 66 93 96 69 66 60 42 340 270 260 150 38 50 13th 79 77 44 11th 15th 4th 180 160 154 151 146 131 99 113 0 89 86 84 81 73 55 63 0 400 320 290 270 240 180 29 25th 0 80 73 68 60 45 7th 6th 0 146 135 136 102 94 85 60 92 93 70 64 58 4th 340 270 250 90 50 25th 13th 79 74 27 15th 7th 4th 178 171 169 162 156 117 106 97 0 96 95 91 87 65 60 55 0 390 330 300 290 250 250 140 25th 0 85 77 74 64 36 6th 6th 0

Sample 2

Tensile strength / Kp / em ^Ä .

% of the original

Extensibility

° / "from the original sample 3

Tensile strength / Kp / cm ¹ .

° / ₀ from the original

Extensibility

° / _e from the original sample 4

Tensile strength 'Kp / cm *.

% of the original

Extensibility

° / o from the original Sample 5

Tensile strength / Kp / cm *.

° / ₀ from the original

Extensibility

° / "from the original

Table II shows very clearly the greater increase in life of conductor samples 2 and 4 after Invention in comparison with samples 3 and 5, which are perfect after aging in an air oven at 158 ° C for 90 days failed. About the novel interaction of the crosslinked ethylene polymer layer and the To show impregnated asbestos layer, a sample 7 was produced, which is essentially the Sample 2 is the same, but with a cellulose acetate interlayer between the crosslinked polymer layer and the impregnated asbestos layer. Sample 7 is hot after aging in an air oven for 90 days 158'C completely off.

Sample 2 was the subject for approval as a line for an operating voltage up to 300 V and an operating temperature up to 150 ° C prescribed Prii-, _levies%. The test results were sufficient for the

Approval regulations.

Samples 1, 6 and 4 were also tested for dielectric strength as well as for isola tion resistance after different periods of heat aging investigated. When examining the through Impact resistance, the samples were initially held at 1500 V for 1 minute, whereupon the breakdown voltage was detected. In Table III below, the three different ver search determined breakdown voltages listed in kV, with the first attempt the sample aul a 12 mm spindle, wound onto a 6 mm spindle on the second attempt, and on the third attempt Was bent in a U-shape.

Table ΙΪΪ Aging Tempe test 12mm Sample 1 U-shaped 12mm 5.0 ICO Sample 6 U-shaped Sample 4 U-shaped rature tempe spindle 6 mm bent spindle 1.1 9.5 6 mm bent 12mm ^; 6 mm bent Days rature spindle Breakdown voltage 1.2 9.1 spindle Spindle spindle 4.9 5.2 1.2 7.2 in kV 11.8 11.2 158 RT 1.4 1.2 6.0 10.0 10.0 10.0 11.3 9.9 2.0 30th 158 RT 1.5 1.4 0.9 8.9 9.4 9.2 1.9 1.6 1.2 60 158 RT 1.3 1.3 1.1 8.7 9.0 7.4 1.1 1.1 1.0 90 RT 4.0 4.4 1.2 8.2 7.9 10.1 1.0; 0.9 10.8 158 150 1.1 1.1 Insulation resistance in 8.9 10.5 10.5 10.5 2.4 30th 158 150 1.3 1.1 10.2 10.8 3.0 1.5 1.3 60 158 150 1.2 1.0 10.7 10.5 1.0 1.2 0.8 90 150 1.5 1.0; 0.7 2080 ΜΩ 158 RT 160 180,000i 30th 158 RT 250 U00 | 60 158 RT 400 102 i 90 158 RT 6th O! 30th 158 150 10 22 ^! 60 158 150 15th 04! 90 150 Oi 20,000 25,000 2000 110 80 40 25th

2387

\O

The samples according to the invention have an improved resistance to the effects of fire when compared to sample 1 which is customary in the trade. To simulate the conditions occurring during actual operation, the samples were heated alternately

and cooled. The samples according to the invention withstood 250,000 temperature changes without seeing damage, while commercial samples 1 failed after 30,000 to 35,000 temperature changes.

1 sheet of drawings

J09 526/353

Claims (6)

1 2 from a polymerizable acrylic acid ester and from patent claims a second impregnation from a partially condensed 1 'sated mixture of an epoxy resin and an acidic unsaturated polymerizable polyester 1. Insulated electrical conductor with a 5 stand. Covering made of a networked, heat-insulated electrical conductor hardened ethylene polymer, thereby making polyolefins, for example polyethylene, a tem- k s i ch nze net that exposed to the ethylene-poly temperature of 150 ⁰ C, then fails after merschicht (3) a fibrous inorganic layer (4) some time the insulation. Electrical conductor with a is arranged, which stand out with a heat-resistant, resin-impregnated asbestos insulation halogenated polymer is impregnated. due to good flame resistance and good resistance 2. A ladder according to claim 1, characterized in that its resistance to moisture can be shows that the ethylene polymer layer (3) leaves something to be desired. hardened polyethylene. The invention has for its object to be a 3. A conductor according to claim 1 or 2, characterized in that 15 insulated electrical conductors of the aforementioned characterized in that the fibrous inorganic type of creating, which is characterized by an excellent Layer (4) consists of asbestos. Heat resistance and flame resistance «as well as heat 4. Identifies conductors according to one of the preceding aging resistance. Proverbs, characterized in that the heat-solving this task is isolated by an Resistant, halogenated polymer chlorinated rubber 20 electrical conductor with a sheath made of a is. cross-linked, heat-cured ethylene 5. Head according to one of claims 1 to 4, polymer characterized according to the invention characterized in that prior to molding, there is a fibrous over the ethylene polymer layer of the insulating material is arranged on the conductor of this previously inorganic layer, which with a is provided with a removable material. 35 heat-resistant halogenated polymer impregnated 6. Head according to claim 5, characterized in that it is marked. Appropriately there is the ethylene polymer, that the strippable material is paper. layer of cross-linked polyethylene and the fibrous inorganic layer of asbestos. The fibrous inorganic layer is expediently made with chlorine-30 rubber impregnated. To facilitate removal of the insulation from the metallic electrical conductor, it is the molding of the insulating material with a peelable material, in particular paper. 35 The drawing shows a preferred embodiment of the invention. With the one shown in the drawing Embodiment is on the metallic conductor a in the form of a multi-core support braid Wrapping 2 made of paper applied, followed by a 40 ethylene polymer layer 3, over which a fibrous inorganic layer 4 is arranged, which is impregnated with a heat-resistant halogenated polymer. The invention relates to an insulated electrical system for the manufacture of the ethylene polymer layer Head with a covering made of a networked. high-pressure polyethylene with a molecular weight are suitable Heat cured ethylene polymer. 45 kular weight in the order of 2000 to From the German Auslegeschrift 1 079 145 are 30,000 and above, low-pressure polyethylene as well already electrical conductors with an insulation made of copolymers of ethylene and lower olefins, Ethylene polymers known, for example, propylene and butene-1 by irradiation. Preferred or through the addition of crosslinking agents with ancillary copolymers consist of 15 to 85 mol percent Turn of heat are networked. 50 propylene and at least 15 mole percent ethylene. In addition, US Pat. No. 2,260,024 already discloses ethylene-propylene rubber and ethylene-propylene an insulated electrical conductor known, the terpolymers, especially terpolymers of ethylene, with a fibrous inorganic layer of, for example, propylene and a non-conjugated diene asbestos, fiberglass or rock wool is also suitable. which is impregnated with a polyamide modified with a synthetic resin if necessary. Furthermore, preferably by chemical means. For this purpose , patent specification No. 2,415 from the Office for Er- den Polymeren is a suitable crosslinking agent in accordance with the invention and patents in East Berlin · Zent added and then on a corresponding kannt, which is heated with a binder from a form- So crosslinking temperature. Preferably veraldehyd and stiffening products of polyvinyl * one turns as crosslinking agents organic per esters · dutch condensation produced resin inside dipped oxy de, which is steeped a decomposition temperature of about 13O ⁰ C. Finally, from the German patent, for example, 2,5-bis (tertiary butyl peroxy font 954 436 is already an insulation for electrical 2,5 dimethyl) hexane and 2,5 ßis (tertiary butyl peroxy) conductors known, which consists of a flexible, fibrous, 65 2,5-dimethyl) -hexyn. Inorganic dicumyl material, for example asbestos or peroxide, is particularly suitable, which preferably consists of a glass fiber based on ethylene, which is impregnated with a resin-like material polymer of 0.5 to 10 percent by weight, the percentage applied from a first impregnation will.