KR20100024993A

KR20100024993A - Insulated electrical conductor

Info

Publication number: KR20100024993A
Application number: KR1020107001159A
Authority: KR
Inventors: 크리스뗄 깡씨쉐르; 렝다 부디아
Original assignee: 넥쌍
Priority date: 2007-06-20
Filing date: 2008-06-18
Publication date: 2010-03-08
Also published as: FR2917886B1; WO2009004246A2; FR2917886A1; EP2160738A2; WO2009004246A3

Abstract

The present invention relates to an insulated electrical conductor comprising an electrical conductor surrounded by an extruded insulating layer obtained in a composition comprising a polymer and a solid fatty acid amide.

Description

Insulated Electrical Conductor

The invention relates in particular to insulated electrical conductors designed to withstand temperatures of -40 ° C.

The invention is applied to insulated electrical conductors, in particular (non-insulated) electrical conductor harnesses having a cross-sectional area of 0.35 mm ² to 7 mm ² , preferably 0.35 mm ² to 1 mm ² , used in the automotive industry.

BACKGROUND Insulating compositions for insulated electrical conductors are known in the automotive industry and these compositions comprise a mixture of polyolefin and paraffin oil to obtain improved low temperature properties.

However, this type of composition is difficult to industrially process by extrusion.

The amount of liquid injected during the processing of the composition in the extruder is a minimum amount of 1 to 2 parts by weight per 100 parts by weight of the polymer in the composition.

As a result, such injections are expensive because they require the use of an oil injector that transports a very accurate measurand, and it is also difficult to extrude such compositions at industrial speed, ie at a rate of 1000 (kg / h) extrusion composition per hour.

In addition, the mechanical properties of these compositions, including paraffin oils, are not good enough to withstand temperatures of -40 ° C.

The present invention provides an insulated electrical conductor comprising an electrical conductor surrounded by an extruded insulating layer, which has improved mechanical properties such that it can be industrially processed easily and at low cost, especially at a temperature of -40 ° C. The above-mentioned problems of the prior art can be avoided.

The solution to the above technical problem according to the present invention lies in the fact that an extruded insulating layer is obtained in a composition comprising a polymer and a solid fatty acid amide.

By the present invention, the composition can be extruded very easily without making any changes to conventional extrusion lines.

The solid fatty acid amide is incorporated into the polymer using a simple metering hopper.

In addition, the extruded insulating layer obtained in the composition exhibits good mechanical properties, and in particular can withstand temperatures of -40 ° C. in accordance with ISO standard 6722 Part B1 §8.1.

In a preferred embodiment, the fatty acid amide can be selected from formulas I and II below.

(I)

(II)

Where

- R1 and R4 are C ₁ of the same, as or different from each other linear or branched _- C ₂₄ Alkyl groups; Or linear or branched C ₂ -C ₂₄ Alkenes; Or C ₅ -C ₂₄ Cycloalkyl group;

R2 is hydrogen; Or linear or branched C_One-C₂₄ Alkyl groups; Or linear or branched C₂-C₂₄ Alkenes; Or C₅-C₂₄ Cycloalkyl group; And

R3 is linear or branched C ₁ -C ₁₀ Alkyl group.

Preferably the fatty acid amides may be selected from the following families: acetamide; Propionamide; n-butyramide; n-valeramide; n-caproamide; Stearamide; Erucamide: lauroylamide; Myristic amide; Arachidamide; Behenamide; Oleamide; Ethylene-bis-stearamide; Ethylene-bis-oleamide; And oleyl palmitamide, and mixtures thereof.

Oleyl palmitamide is particularly preferred.

In a preferred embodiment, the amount of fatty acid amide is 5 parts by weight or less based on 100 parts by weight of polymer in the composition, preferably 2 parts by weight or less based on 100 parts by weight of polymer in the composition.

This upper limit of 5 parts serves to limit the risk of fatty acid amides moving to the surface of the layer. Moving to the surface whitens the surface.

This causes the original nature of the fatty acid amides to tend to no longer protect the entire insulating layer, making the layer easily damaged from its environment.

In particular, the amount of fatty acid amide is at least 0.5 parts by weight based on 100 parts by weight of the polymer in the composition, preferably at least 1 part by weight based on 100 parts by weight of the polymer in the composition.

The polymer properties of the compositions of the present invention are not limited in any way.

To those skilled in the art, any type of polymer known to be suitable for extrusion may be any type of polymer, which polymer is optionally curable.

In a preferred embodiment, the polymer is silane-grafted so that it can be cured by methods well known to those skilled in the art as "silane" curing.

The polymer is preferably a curable polymer of thermoplastic or elastomeric type, selected from one or more olefin homopolymers, one or more olefin copolymers, or mixtures thereof.

Especially preferably, the polymer is an ethylene homopolymer or copolymer, propylene homopolymer or copolymer, or mixtures thereof.

As a preferred example, the polymer is a mixture of polyethylene-octene (PEO) copolymer and propylene (PP) copolymer.

According to the application of the composition according to the invention, the mixture of PEO and PP consists of 60% to 80% by weight PEO and 40% to 20% by weight PP.

By way of example, a composition having a PEO / PP ratio of 60/40 is preferred for insulation of electrical conductors having a cross-sectional area in the range of 0.35 mm ² to 1.5 mm ² (insulation layer referred to as “rigid”), and PEO / Compositions having a PP ratio of 70/30 are preferred for the insulation of electrical conductors having a cross-sectional area in the range of 1.5 mm ² to 7 mm ² (insulation layer referred to as “flexible”).

Compositions with a PEO / PP ratio of 80/20 are preferred for the insulation of electrical conductors having a cross-sectional area of at least 7 mm ² , possibly 90 mm ² or 150 mm ² (insulation layer referred to as “super flexible” ").

In a preferred embodiment, the composition further comprises a flame-retardant filler.

The flame-delay filler is a metal hydroxide, the metal hydroxide is preferably magnesium dihydroxide (MDH) or aluminum trihydroxide (ATH).

In one preferred embodiment, the composition further comprises one or more protective agents selected from antioxidants and metal deactivators, wherein the metal deactivators serve to limit catalytic degradation of the insulating layer by the metal of the electrical conductor.

Typically the antioxidant may be phenol or thioester and the metal deactivator may be a phenolic compound well known to those skilled in the art.

In a particularly preferred embodiment, the electrical conductor has a cross section of 0.35 mm ² to 7 mm ² , preferably 0.35 mm ² to 1 mm ² .

Other features and advantages of the invention will be more apparent from the following examples, which do not limit the invention.

The insulated electrical conductor of the present invention is industrially useful as it is surrounded by an extruded insulating layer with improved mechanical properties so that it can be easily and industrially processed at a temperature of -40 ° C.

In order to show the advantages of the composition of the present invention, an extruded insulating layer is prepared from the composition of the present invention and from the composition according to the prior art, and its mechanical properties and "cold forming (-40 ° C)" are determined according to ISO standard 6722 Tested according to.

The manner in which the insulating layer is produced, in particular the manner in which it is cured, is as described below, but this is purely illustrative and is not limited thereto.

In the first step, 100 parts by weight of the polymer was mixed continuously while heating, using a booth single screw or double screw extruder, with about 2.5 parts by weight of silane type curing agent (alkoxysilane or carboxysilane) and organic peroxide.

The temperature of the mixture of the first stage was typically adjusted to process the polymer as the organic peroxide decomposed.

The polymer is a mixture of 80% by weight Engage 8450 and 20% by weight Moplen RP315M.

Engage 8450 is a commercially available polyethylene-octene (PEO) copolymer from supplier Dow Elastomer and Moplen RP315M is a commercially available propylene (PP) copolymer from Supplier Baswell.

The first step is to obtain a silane-transplant polymer, which is usually obtained in the form of granules.

In the second step, 100 parts by weight of the silane-transplant polymer (granule) was mixed continuously with heating in varying amounts of flame retardant filler, protective agent, paraffin oil, or fatty acid amide as shown in Table 1 (Samples A-C). .

The amounts specified in Table 1 are usually expressed in parts by weight per 100 parts by weight of the polymer in the composition.

In particular in the example of preparing the insulating layer disclosed herein, those skilled in the art will readily understand that the amounts given in Table 1 are expressed in parts by weight per 100 parts by weight of the silane-transplant polymer in the composition.

Sample A B C Silane-transplant polymer 100 Flame retardant filler 156 Protection 10 Wave 150 0 One 0 Crodamide 203 0 0 One

The origin of the various components of Table 1 is as follows.

Sunpar 150 is a commercial paraffin oil from Sun Oil.

Crodamide 203 is a fatty amide of the solid oleyl palmitamide type available from Croda France.

Flame retardant fillers are ATH commercially available from Albermalesa.

The protecting agent may be a combination of one or more antioxidants, such as Iganox® 1010 and / or Iganox PS # 802, and one or more metal deactivators, such as Iganox 1024 and / or Naugard XL1, wherein the specific antioxidant Agents and metal deactivators are purely selected for illustrative purposes.

Mixing of the second stage was carried out using different booth single screw or double screw extruders.

Flame retardant fillers, protective agents and fatty acid amides were added using conventional metering hoppers.

Paraffin oil was added into the polymer using an injection molding machine.

The mixing temperature of this second step is adjusted to allow processing of the silane-transferred polymer granules while avoiding decomposition of the flame retardant filler.

The second step is to obtain a filled silane implant polymer, which is usually obtained in granular form.

The silane implanted polymer granules filled in the third step were processed in a single screw extruder in the presence of a catalyst for the condensation reaction of the silanol groups.

The catalyst was typically added to the filled silane implant polymer in the form of a master batch mixture of polyolefins compatible with the implant polymer.

As an example the master batch containing the catalyst was added to the filled silane implant polymer in an amount of about 2% by weight.

The filled silane implanted polymer and silanol condensation catalyst mixture is extruded, for example, on (polywire) copper wire having a cross section of 1 mm ² , 0.25 mm thick to obtain an insulating layer.

In the fourth step, the insulating layer is cured in the presence of water to obtain an insulated electric conductor (insulated electric conductors A to C).

The foregoing process constitutes silane cure well known to those skilled in the art, in particular it is known as "moisture" cure or "sauna" cure.

Other methods known to those skilled in the art can also be used to cure the polymers of the compositions of the present invention.

In particular, the composition can be photochemically cured using radiation in the form of ultraviolet light in the presence of radiation such as beta rays or photoinitiators.

Two other feasible methods are salt bath curing or curing in steam tubes in the presence of organic peroxides.

To test the strength at about −40 ° C., the insulated electrical conductors A to C were “cold formed” and the results are summarized in Table 2 below.

At the beginning, mechanical properties such as traction strength or breaking elongation of the insulated electrical conductor insulation layer were measured and are shown in Table 2 below.

Insulated electrical conductors A B C Tensile Strength (MPa) 18.5 18.1 18.2 Elongation at Break (%) 165 175 190 Cold forming (-40 ℃) failure failure pass

Cold forming in accordance with ISO Standard 6722 Part 1 §8.1 consists of twisting two insulated electrical conductors, each 600 mm in length, with a co-mandrel at -40 ° C.

After such cold forming, at ambient temperature, it was visually inspected whether the electrical conductors were visible, that is, whether there were cracks in the insulating layer on the insulating electrical conductors and the electrical conductors were visible.

The electrical conductors of insulated electrical conductors A and B were clearly visible, while the insulating layer of insulated electrical conductors C did not show any external damage.

Fatty acid amides contained in the insulating layer of the insulating electrical conductor C increase the motility of the polymer chain, improving the cold behavior (-40 ° C.) of the insulating layer.

It is also noted that the break elongation of the insulating layers of the insulated electrical conductors C is much better than the break elongation of the insulating layers of the insulated electrical conductors A and B.

The present invention is not limited to the above examples and generally extends to all compositions that can be expanded based on the general teachings of the present disclosure.

Claims

An insulated electrical conductor comprising an electrical conductor surrounded by an extruded insulating layer obtained in a composition comprising a polymer and a solid fatty acid amide.

The insulated electrical conductor of claim 1, wherein the fatty acid amide is selected from formulas I and II.

(I)

(II)
Where
R 1 and R 4 are the same or different from one another and are linear or branched C ₁ -C ₂₄ alkyl groups; Or a linear or branched C ₂ -C ₂₄ alkene group; Or a C ₅ -C ₂₄ cycloalkyl group;
R2 is hydrogen; Or a linear or branched C ₁ -C ₂₄ alkyl group; Or a linear or branched C ₂ -C ₂₄ alkene group; Or a C ₅ -C ₂₄ cycloalkyl group; And
R 3 is a linear or branched C ₁ -C ₁₀ alkyl group.

The method according to claim 1 or 2,
Insulated electrical conductor, characterized in that the fatty acid amide is oleyl palmitamide.

The method according to any one of claims 1 to 3,
And wherein the amount of fatty acid amide is 5 parts by weight or less based on 100 parts by weight of polymer in the composition, preferably 2 parts by weight or less based on 100 parts by weight of polymer in the composition.

The method according to any one of claims 1 to 4,
Insulated electrical conductors, characterized in that the amount of fatty acid amide is at least 0.5 parts by weight based on 100 parts by weight of polymer in the composition, preferably at least 1 part by weight based on 100 parts by weight of polymer in the composition.

The method according to any one of claims 1 to 5,
Insulated electrical conductor, characterized in that the polymer is selected from one or more olefin homopolymers, one or more olefin copolymers, or mixtures thereof.

The method according to any one of claims 1 to 6,
Insulated electrical conductor, characterized in that the polymer is a mixture of polyethylene-octene (PEO) copolymer and propylene (PP) copolymer.

The method of claim 7, wherein
The mixture of polyethylene-octene (PEO) copolymer and propylene (PP) copolymer is 60% to 80% by weight polyethylene-octene (PEO) copolymer and 40% to 20% by weight propylene (PP) copolymer Insulated electrical conductor, characterized in that the mixture of.

The method according to any one of claims 1 to 8,
Insulated electrical conductor, characterized in that the polymer is a silane-transplanted polymer.

The method according to any one of claims 1 to 9,
Wherein said composition further comprises flame-delay filler.

The method of claim 10,
Wherein the flame-delay filler is a metal hydroxide, the metal hydroxide is preferably magnesium dihydroxide (MDH) or aluminum trihydroxide (ATH).

The method according to any one of claims 1 to 11,
The composition is an insulated electrical conductor, characterized in that it further comprises at least one protective agent selected from antioxidants and metal deactivators.

The method according to any one of claims 1 to 12,
The insulated electric conductor according to claim 1, wherein the electric conductor has a cross-sectional area of 0.35 mm ² to 7 mm ² , preferably 0.35 mm ² to 1 mm ² .