MXPA99009174A - Crosslinkable polyolefin-based polymeric composition with a high thermal coefficient of service in a motor vehicle cable and process for preparing the same - Google Patents

Abstract

Una composición polimérica y proceso de preparación, la cual comprende una mezcla de poliolefinas reticulables con elevado coeficiente térmico de servicio en cable automotriz, caracterizado por una mayor resistencia al ataque químico de aceites a alta temperatura 150§C, resistencia a la propagación vertical de la flama, e incremento de la resistencia a la abrasión para aplicación en compuestos para aislamiento y cubierta de cables y conductores eléctricos. Las poliolefinas son una combinación químico sinergística entre una carga de hidrocarburos halogenada combinada con trióxido de antimonio un alcoxisilano, un agentede reticulación, una combinación de aditivos como ayuda de proceso y una combinación de tres agentes antioxidantes.

Description

POLEVÍERICA COMPOSITION BASED ON RETICULABLY POLIOLEPHINES WITH HIGH THERMAL COEFFICIENT OF SERVICE IN AUTOMOTIVE CABLE AND PREPARATION PROCESS BACKGROUND OF THE INVENTION FIELD OF THE INVENTION: The invention relates to a polymeric composition based on crosslinkable polyolefins with high thermal coefficient of service up to 150 ° C as insulation in automotive cable and to the process of promoting in a mixture of crosslinkable polyolefins with halogens that are grafted to the chain of the polymer and that by means of a combination of additives they confer to the formulation for isolation and cover of cables and electrical conductors a temperature of higher thermal service with characteristics such as: temperature of service of 150 ° C, resistance to the vertical propagation of flame, resistance to oils at 136 ° C, and resistance to abrasion.

Description of the state of the art: A wide variety of inventions applicable to the formulation of various types of insulators for cable sheath and electric conductors are known, for example in the patent US 5,401787 there are described insulating compositions retardant to the f , improved to moisture and curable from ethylene-alkoxysilane-halogenated anhydride copolymers and antimony trioxide that complies with SAEJ-1 128.

US Pat. No. 5,439,965 describes flame-retardant and abrasion-resistant interlaced compositions as insulators for wires and cables based on ethylene vinyl acetate copolymer, a halogenated compound, antimony trioxide and an organic peroxide.

US Pat. No. 5,955525 describes a formulation for insulation and protection of cables and electric conductors resistant to the flame of low smoke emission with thermal coefficients of 135 ° C.

The above inventions are practically limited to the flame resistance or even the abrasion, but at lower thermal coefficients of service except the last invention owned by the applicant operating at thermal temperature coefficients of the product up to 135 ° C.

One of the main applications of the present invention is that the polymeric compositions of cross-linkable polyolefinic type with high thermal coefficient provide the insulation of electrical cables and conductors of automotive type, a greater security in the operation of the cables especially when these are in areas where the heating of the motor is high and therefore the physical properties, and the thermal stability of the compositions should not deteriorate under said operating conditions. hot, as well as its resistance to flame and abrasion.

The compositions are applied as insulation in cables and electrical conductors to reduced thicknesses of 0.15 - 0.40 millimeters of thickness according to the standards for primary low voltage cables ISO 6722 Class D. RENAULT 36-05-009J and for UL 150 ° C cables according to to UL 3321. In addition it additionally fulfills the following specifications DELPHI ESM-3207, ESM-3300 and ESM-3269: CHRYSLER MS-9502 and FORD WSS 22P7 A4. The compositions present a good balance of the main properties such as processability, physical, chemical, and electrical with that of flame resistance, resistance to oils and resistance to abrasion. The main advantages obtained when developing said compositions are: (a) with the combination of additives they provide greater thermal stability and insulating compounds and / or thermal class covers 150 ° C (b) are obtained with the use of flame retardant agents based on halogens that are grafted to the polymer chain, greater resistance to vertical propagation of the flame (c) is obtained and colorable compositions can be obtained.

For the present invention, a wide variety of antioxidants were used, such as: I, 2-dihydro-2,2,4-trimethyl quinoline, and sterically hindered phenols combinations with distearil 3,3'thio-dipropianato (DSTDP), bis ( 2,4 di terbutyl) pentaerythritol diphosphite, tris (2,4-diterbutyl phenyl) phosphite, zinc salt 2, mercapto benzimidazole, zinc salt 2-mercapto toluylmidazole, pentaerythritol tetra bis (betalaurylthiopropionate) and dilauryl 3,3'thio-dipropianate.

Combinations of di-alkyl-thio-dipropianate with hindered phenols provide high thermal stabilities DETAILED DESCRIPTION OF THE INVENTION The polymeric composition with resistance to vertical propagation of the flame, resistance to oils, resistance to abrasion and mainly with a high thermal stability at service temperatures up to 150 ° C, subjected to aging times of long duration at 3000 hours until cable operating temperatures of 150 ° C ± 5 ° C already aged for a short duration of 240 hours at a temperature of 180 ° C, ± 3 ° C is based on a copolymer of ethylene and vinyl ester of an aliphatic carboxylic acid alone or combined with another series of polyolefins with a series of active components that significantly improve thermal stability, resistance to vertical propagation of the flame, and resistance to oils at 136 ° C and resistance to abrasion. The amounts of the components are expressed in parts per hundred of resin or the sum of this with other resins involved The components used in the composition of the present invention defined qualitatively and quantitatively are described below.

Ethylene copolymer The polymeric component of the present composition is a copolymer of ethylene and vinyl ester of the C 2-6 aliphatic carboxylic acid, such as vinyl acetate, vinyl propyanate, vinyl butyral vinyl pentanoate or vinyl hexanoate. The copolymer preferably used is an ethylene and vinyl acetate (EVA) wherein said copolymer (EVA) can contain vinyl acetate in an approximate ratio of 3% to 90% and preferably from 3% to 45% with the remainder being ethylene . The terpolymers of ethylene, vinyl acetate and other types of polymerizable olefinic monomers can be employed in suitable proportions.

It is also possible to use other types of polymers such as polyethylene, polypropylene, copolymers and ethylene-propylene terpolymer and acrylic copolymers. Low density polyethylenes, linear low density polyethylenes, and high density polyethylenes have melt indices of 0.5 to 20 g / 10 min. to promote uniform and acceptable blends, mainly when the proportions are 30% or less over the total polymer composition.

The ethylene copolymers and the mixtures have melt indices in the range 0.1 to 7 g / 10 min. EVA copolymers generally have a melt index of 0.5 to 5 g 10 min.

Active Components Loading of halogenated organic compounds The fillers used in the composition of the present invention are brominated organic fillers that do not generate dioxins and furans upon combustion and in addition to being approved by the EPA. (Office of Environmental Protection USA for the Prevention of Pollution and Regularization of New Substances, Toxic Pending Information Development) The chemical structure of these charges is composed of a cycloaliphatic ring combined with bromine atoms, such as: Octabromotrimethylphenyl Indane H18 Br? 2Br8-Br, 73.7% (Fusing temperature 240 ° C 256 ° C) FR-1808® trademark of Dead Sea Bromine Group.

Monomer Pentabromobenzyl acrylate C ^ H 5 Br 5 O-Br, 71.8% (melting temperature 117-120 ° C) .FR-1025® trademark of Dead Sea Bromine Group.

Among other halogenated compounds that can be used in the composition as a reference are the following: • hexabromobenzene, tetrabromobisphenol A, tetrachlorobisphenol A, anhydrous tetrabromophthalate, hexabromo cyclodecane, octabromodiphenyl, perchloropentacyclohexane, octabromodiphenyl ether decabromodiphenyl ether, tribromo phenyl allyl ether, pentabromo ethylbenzene 2,4,6-tribromophenol, pentabromodi phenyl ether, ethylene bis (tetrabromophthalimide), anhydrous tetrachlorophthalate, poly (pentabromobenzyl) acylate, bis (dibromopropyl) ether of tetrabromobisphenol A, and Diels-Alder byproduct of hexachlorocyclopentadiene with maleic anhydride.

The brominated compounds used in the present invention allow obtaining grafts in the polymers used.

Antimony trioxide The use of antimony trioxide with the brominated compounds produces a chemical synergy effect that improves the resistance to the flame. The ratios employed of brominated compounds with antimony trioxide employed were 2: 1 to 5: 1 and more preferably 2.5: 1 to 4: 1. Other types of complementary additives can be used to achieve synergy between the brominated compounds, which may be: antimony pentoxide, antimony silicate, boron compounds, tin oxide, zinc oxide, zinc borate, aluminum trioxide, and aluminum trihydroxide.

The use of these charges will basically depend on the degree of flame retardancy to be achieved and on the viscosity that the polymer composition reaches by increasing the proportion of the same, therefore they can be included if complementary thermohorgonic loads are required. halogenated such as: alumina trihydrate (Al2? 3H2O or Al (OH) 3, magnesium hydroxide, calcium silicate hydrate, magnesium carbonate hydrate, etc. These charges are pretreated with an alkoxysilane. can obtain a physicochemical coupling that offers greater fixation of the charge to the polymer.

The particle size of the charge must be according to the Theological characteristics necessary to reach the processability conditions of the most optimal polymeric compositions, and with this also reach the physical-mechanical, flame-retardant and chemical characteristics necessary to satisfy the application requirements.

Alkisilanes The alkoxysilanes used were: vinyl trimethoxyethoxysilane, phenyl tris (2-methoxyethoxy) silane, methyl triethoxysilane, methyl-methyl tris- (2-methoxyethoxy) silane, dimethyl diethoxysilane, ethyl trimethoxysilane and viml trimethoxysilane.

Especially preferred alkoxysilanes by conferring better properties to the polymer composition are: • Vinyl trimethoxyethoxysilane, of formula • Vinyl trimethoxysilane, of formula: The proportions of the alkoxysilanes are between 0.5-5 phr. (Parts per cent of resin) Crosslinking Agents Base compositions of ethylene and vinyl acetate can be crosslinked using the usual traditional crosslinking methods, such as by thermal moisture and / or radiation, the crosslinking agents employed in the present composition are: dicumyl peroxide and alpha, alpha'-bis (terbutyleneperoxy) diisopropylbenzene with the combination of coagents such as triallyl cyanurate, triallyl. ,,, tetracrilato, trimetilol propane triacrilato, trimetilol propane, trimetacrilato, tetretileno glycol dimethacriiate, low molecular weight polybutadiene and n, n'-m-fenilendimaleico in order to improve the state and speed of crosslinking, being the peroxide alpha, - alpha 'bis (terbutylperoxy) diisopropylbenzene and the n, n'-m-phenylenedimale coagent known commercially as HVA-2® are preferably used for the development of the present invention, the proportions of coagent and crosslinking agent can be 0.5-10 phr. The organic peroxides are activated during the vulcanization processes, producing chemical bonding between the ethylene vinyl acetate polymer chains in a three-dimensional matrix of carbon-carbon chains. In order to carry out the chemical crosslinking in the present invention, it will be possible to use other crosslinking agents that generate free radical radicals such as 2.5 - (tert-butylperoxy); 2,5-dimethylexin-3; di-tert-butylperoxide; 2,5- (tert-butylperoxy) -; -2,5-dimethylexane; tert-butylcumyl peroxide. For the selection of the crosslinking agents it is necessary to take into account the decomposition temperatures of the same to avoid undesirable effects during the mixing and extrusion processes, the amounts and / or proportions to be used of the curing agents will be defined in depending on the type of application, because in,. As the content of the agent increases in the formula, the following properties will be improved or reduced: Higher and / or lower thermal stability after aging in short and long duration oven, and under operating temperatures of 150 ° C.

• Greater and / or lower resistance to ignition and resistance to combustion. • Greater and / or lower resistance to the attack of corrosive chemical fluids. • Greater and / or lower resistance to oils. • Greater and / or lower resistance to abrasion • Greater and / or lower dielectric strength. • Greater and / or lower resistance to humidity or to the gain and / or loss of electrical properties due to the absorption of water in the polymeric compositions.

Additive agents to apply the composition as an insulating compound with a high thermal coefficient at service temperatures of up to 150 ° C for cables or electrical conductors of the automotive type with ISO standards class D6722, FORD S97G 14401-AA RENAULT 36-05-009 / J , FORD 22P7 A4, DELPHI ESM 3207, ESM-3300 and ESM-3269 AND CHRYLER MS-95020 Process Additives The process additives used in the present invention allow the compositions to be easily mixed and / or prepared and / or extruded and / or shaped. The composition of the process additives is composed of the following components: • A fatty acid and / or derivative of the fatty acids referred to the aliphatic carboxylic acid of 8 to 22 carbon atoms, saturated and unsaturated, such as stearic acid, caproic acid, isostearic acid, lauric acid STRUKTOL TR 016 (mixture of metallic soaps of fatty acids with an amide) and the latter being especially preferred, due to its ability to promote good Theological properties; • A low molecular weight silicone oil, being an excellent promoter to avoid the adhesion of the compositions on metal surfaces, mixing equipment, extrusion and mainly in copper electrical conductors.

* An aliphatic resin (STRUKTOL TR 060) can be used preferably to improve the dispersion and / or homogeneity of the inorganic fillers, antioxidants, and crosslinking agents of the polymeric composition The proportions employed in each system will be from fatty acid to silicone oil 1: 1 to approximately 1: 6, and preferably from fatty acid to silicone oil 1: 3. And with respect to the aliphatic resin to the fatty acid 1: 1 to about 1: 6 and preferably of hydrocarbon resin to fatty acid 1: 3. The total amount of the composition of the process additives is from 0.25 phr to 8 phr of the total polymer composition.

Antioxidants capable of withstanding continuous operating temperatures of 150 ° C ± 5 ° C for 3000 hours and / or aged in a 240 hour oven at 180 ° C ± 3 ° C were used in the present invention. Basically the invention contemplates the use of an oven of 240 hours at 180 ° C. ± 3 ° C Basically, the invention contemplates the use of a package of antioxidants capable of complying with the above requirements and also preventing the antioxidants used from discoloring and / or staining the copper of the electric conductor of the cable, as well as modifying the tone of the pigmented compound at the time of steam-crosslinking the polymer compositions containing said antioxidants.

The antioxidants especially preferred in the present invention are: • 2 mercapto benzimidazole zinc sai (VULKANOX ZMB2) BAYER® • 2-mercaptotoluylimidazole zinc salt • 2,2'-thiodiethyl bis- (3,5-diterbutyl-4-hydroxyphenyl) propionate, and • Pentaerythritol tetra bis (beta-laurylthiopropionate) The amounts and / or proportions employed in the polymer compositions are preferably 0.25-15 phr.

The invention is described below in order to illustrate the same but of course without reducing its scope, through the following examples of preparation and application process of the polymeric insulating composition that meet the following requirements: Formulation, Experimentation and Preparation of the Composition. All the components described above can vary widely; however, the composition object of the invention is precisely the interaction of the vinyl alkoxysilane with the inorganic filler and the mixture of polymers used during the process of mixing and / or preparing the polymer composition. The wrong dosage of silane or quantities lower than 0.5 to 5.0 phr, may be insufficient to provide surface treatment to the inorganic filler and be sufficient to provide surface treatment to the inorganic filler, and amounts above these ranges may give us undesirable effects. in the physicomechanical properties after vulcanization of the material.

The mixture can be made in an internal mixer such as the mixers: Banbury, Boiling Mixtrumat, and in continuous mixer such as: Farrel, Wemer & Pfleider and Buss. The other components of the polymer composition are also mixed in the aforementioned mixing equipment, after the first addition of silane, filler and polymers. Once all the components of the different polymeric compositions expressed in the present invention are added, intensive mixing thereof is carried out (all the components must be mixed at the same time, this has the purpose of promoting a good dispersion). The duration of mixing will depend on the degree of dispersion and the sequence of mixing used for each type of equipment. In summary, any known processing equipment can be used, the main objective is to ensure an intimate mixture of the essential components. In addition to the essential components there are also other components, such as UV stabilizing pigments and / or fungicides, these components must be selected carefully because they can interfere with the crosslinking system of the polymer composition.

The amount and / or proportion of the curing agent will depend on the degree of crosslinking that is desired and / or is according to the type of application; insofar as the crosslinking agent is in greater quantity and / or proportion, the crosslinking density will be higher and the final properties of the composition such as hardness, resistance to attack by chemicals, abrasion resistance, resistance to the oils, and the electrical properties are better. And to the extent that the amount and / or proportion of the curing agent is lower the crosslinking density will decrease and therefore the final properties will also decrease (thermal stability loss at high temperatures and / or operating temperatures of the cable) . The density of crosslinking recommended to achieve a good balance in properties will be 85% and / or higher, in practice the typical values of the crosslink density are from 85% to 95%. The way to measure the crosslink density is by means of extraction of the undissolved crosslinked polymer in a solvent used to carry out the extraction, this procedure is according to the method ASTM D 2765, Method C. The levels employed of the agents of Cured of the present invention were from 0.5 phr to 10 phr, preferable from 1 phr to 6 phr or from 2 phr to 4.5 phr. The curing agents are according to the degree of crosslinking obtained.

The quantity and / or proportion of the process additives depends on the Theological properties necessary for the good processing of the material during the mixing and extrusion of the material. The addition of these additives to the process aid should not affect the speed and degree of crosslinking of the polymer composition. This amount and / or proportion of the process aid additives will be from 0.25 phr to 8 phr.

The present invention is not limited to the use of a single type of component for the process aid, but it is possible to use a system of two and up to three types of components, these can be conjugated in forms and quantities in such a way that synergistic effects are achieved that confer excellent Theological properties. The amount and type of antioxidants used will depend basically on the application and / or operation temperatures to which the polymeric compositions will be subject. The preferred antioxidants are: zinc salt 2 mercapto benzimidazole pentaerythritol tetra bis (betalaurylthiopropionate) and 2,2'-thiodiethyl bis (3,5-ditertiary 4-hydroxyphenyl) propionate. The amounts and / or amounts used of this antioxidant system is preferably 0.25 phr at 15 phr or 1.5 ph at 12 phr. The relationship between them will be between 1: 1 to 3: 1 and 1: 1 to 2.5: 1. by using conventional crosslinking processes as long as they do not affect the speed and degree of crosslinking and therefore the final properties.

The final result is to have polymer compositions that meet the following requirements: • Resistance to inclined and / or vertical propagation of the flame according to ISO 6722 and RENAULT 38-05-009J respectively. • Sufficient thermal stability to withstand oven aging temperatures of 150 ° C +/- 3 ° C and 240 hours at 180 ° C. • Electrical properties for voltages less than and equal to 600 volts and voltages less than and equal to 5000 volts. • Resistance to ASTM 1 oil under the following temperature and immersion period: 136 ° C-for 48 hours. • Resistance to fluids confora to ISO 6722 and RENAULT 38-05-009J. • Polymeric compositions should not discolor and / or stain copper and should not change colors when performing the curing of the same. • The compositions must have good Theological characteristics, to achieve mixing and extrusion and these compositions at high line speeds.

A copolymer of ethylene and vinyl ester of a C 2-6 aliphatic carboxylic acid was prepared, preferably vinyl acetate (EVA) in a proportion of 3% to 90% and preferably 3 to 12% of vinyl acetate and the copolymer moiety of ethylene, being mixed in the following way: • Mixed in a Banbury, under controlled conditions of temperature and mixing time (110 ° C to 135 ° C discharge temperature of the material with period of 3-6 minutes of mixing). The mixing period and mixing temperature are limited to the quality and degree of dispersion of the components. Once mixed the polymer compositions are laminated and granulated for extrusion.

• When the tests are made in the form of a plate, they are molded according to the sum of two 90% curing times determined in the Monsanto ODR rheometer at 180 ° C. This is to ensure that for each type of formulation expressed in the examples a minimum 85% crosslinking is obtained. The plates are molded under pressure in laboratory presses, stress tensile properties and elongation at rupture are made according to the test method ASTM D 638. The crosslink density was determined by the method ASTM D 2765, Method C.

• When the tests are done as insulation in cable, the insulation is applied in a CV Continuous Reticulation Machine which has a Royle extruder with a diameter of 65 mm and with a L / D of 15: 1 and with extrusion screws with the compression ratio from 2.5: 1 to 3.5: 1 and with the vulcanization tube length of 65 m. At the moment of the extrusion of the formulations of the examples a pack of meshes 20 mesh + 40 mesh + 60 mesh was used; The extrusion temperature profiles used are from 90 ° C to 95 ° C in the areas of the extrusion chamber and in the head and given from 100 ° C to 105 ° C respectively. The extrusion speed is 30 rpm. The insulation thicknesses are 10 mils in 20 AWG gauges.

• Once the prototype cables have been manufactured, the tension stress retention and elongation to rupture properties after aging in ho or at the following test conditions are evaluated: 3000 hours for 150 ° C +/- 3 ° C; 342 hours at 150 ° C; and 240 hours at 180 ° C ± 3 ° C.

• Electrical tests are determined in accordance with ISO-6722 and ASTM D 150.

EXAMPLE I The following formulation was prepared as described above, the mixture contains a copolymer based on a polyolefin of ethylene and vinyl acetate (12% VA and melt index of 2.5 g / lOmin) With the following formulations resistance to the vertical propagation of the flame in accordance with the RENAULT standard 38-05-0091 FR-1808 is commercially known as a retardant to the crystalline flame FR-1025 is commercially known as a retardant to the crystalline flame The sterically hindered phenol used was the propianate 2'2 thiodetií bis (3,5 diterbutil 4 hydroxyphenyl) The composition was prepared according to the description in the summary of cable examples. , according to the RENAULT standard 38-05009J The results obtained after the evaluation are Feature Unit Formula 1 Formula 2 Formula Formula 4 Vertical propagation to the Do not become extinct It is extinguished Flame is extinguished according to extinguish in in in RENAULT 38-05-009J 15 seconds 4 seconds 2 seconds The results are satisfactory and demonstrate that the halogenated flame retardant materials used are suitable to comply with the Flame Test of the RENAULT standard. The operating voltages for this type of composition are 600 volts at 500 volts according to ASTM D 150 EXAMPLE p Example I formula 3 is repeated, only the type and amount of antioxidant is modified. The antioxidant tetra [methylene (3,5-di-tert-butyl-4-hydroxyhydrocinnamate)] was used. methane for the purpose of carrying out a comparative study to demonstrate that the antioxidant propianate 2,2'thiodietil bis (3,5-tert-butyl 4-hirophenyl) is able to withstand aging in short (240 hours) and long-term (3000 hours) Different test temperatures (150 ° C and 180 ° C).

The measured properties are: tensile stress and elongation to rupture, tension stress retention and elongation to rupture.

The composition was prepared as described in the example summary in the form of a cable. The results are expressed in the following table: The results obtained show that the use of antioxidant propianate 2'2 thiodietil bis (terbutylthio 4 hydro phenyl) Formula 1, good thermal stability is obtained As a result it is also observed that the polymer composition of Example I does not discolor and / or stain the copper a Once the material is vulcanized, it is also observed that the original tone of the material once vulcanized does not change.

EXAMPLE IH Four comparative formulations Formula 1 of Example 1 and three others were prepared using the following polymers 1. Ethylene Vinyl Copolymer (9% VA, Fluency Index of 2.2 g / 10 min) 2. Vinyl Ethylene Combination (12% VA, Fluency Index of 2.5 g / 10 min) with an INSITE® polyolefin (index of Fluidity of 0.75 g / 10 min). 3. Vinyl Ethylene Combination (12% VA, Fluency Index 2.5 g / 10 min) with a high density polyethylene with a flow rate of 0.5 g / 10 mm needle diameter): Polyolefin INSITE ** polyolefin manufactured under the process known commercially as INSITE patented by DOW CHEMICAL For this type of reduced wall cable the required value is 100 cycles; according to the result obtained in the invention there is the combination of INSITE® polyolefins and high density polyethylenes, there is a substantial increase in resistance to needle abrasion. This result is not intended to limit the state of the Art of the present invention.

EXAMPLE IV Five comparative formulations Formula 1 of Example I and four others were prepared using the following polymers: 1. Combination of Vinyl Ethylene (12% VA, Fluency Index of 2.5 g / 10 min) to 26% with a polyolefin INSITEF ( Fluidity index of 0.75 g / 10 min) to 9%. . min.) to 26% with a high density polyethylene with a flow rate of 0.5 g / 10 min. to 9%. 3. Combination of Vinyl Ethylene (12% VA, Fluency Index of 2.5 g / 10 min.) To 26% with VAMAC D® 9% acrylic ethylene copolymer.

As a result of these formulations applied as insulation in cable 22 AWG type TXL according to the specification of FORD S97GG 14401 AA the following results of resistance to oil absorption are obtained: TYPE OF OIL ASTM I IRM-902 IRM-903 TRANSMISSION FORMULATION 136 ° C / 48 50 ° C / 20h 50 ° C 20 fa 50 ° C / 2O H % increase in thickness of the insulation of the cab e Formula 1 Example 1 27.8 7.8 2.2 15.8 12% VA plus 4.0S 14.2 12.3 polyethylene INSITE 12% VA plus polyethylene afte 3.2 2.22 5.5 5.4 density 12% VA plus ethylene copolymer 1.22 0.78 3.5 2.21 acrylic or Vamac De® Polyolefin? NSIT? ® Polyolefin manufactured under the process known commercially as INSITE patented by DOW CHEMICAL Vamac D 'name commercially known as a copolymer of ethylene acrylic.

Acrylic density and copolymers shows a substantial increase in resistance to oil absorption.

EXAMPLE V Based on all the formulations of the previous examples, a global polymeric composition is obtained, with which all the synergistic effects are achieved together that confer the resistance to hot oils, to abrasion of the needle, to the propagation to the flame. vertical, and mainly to a greater stability at 150 ° C to 3000 hours.

- It is commercially known as a challenge to a critical mistress. FR-1025® is commercially known as a crystalline flame retardant. The sterically hindered phenol used was propianate 2,2'-thiodiethyl bis (3,5-diterbu-4-hydroxyphenyl). STRUKTOL TR 016 is commercially known as a mixture of metal soaps of fatty acids and with an amide STRUKTOL TR 016® commercial product of aliphatic resin The results obtained after the evaluation are as follows: • The measured properties were; resistance to vertical propagation to the flame in accordance with the RENAULT standard 38-05-009J • The results are good and demonstrate that the material retardant to the halogenated flame used is appropriate to comply with the Flame Test of the RENAULT standard.

• The results obtained show that with the use of the thermal stabilizers proposed in the present example good results are obtained during a prolonged exposure in the furnace of 3000 hours at 150 ° C according to the RENAULT standards 38-05-009J FORD S97GG 14401- AA. and ISO 6722 (all the compositions were extracted in thin-gauge 22 AWG wire, and were evaluated according to the aforementioned standards as cable insulation with the entire copper core). As a result it also has that the three polymer compositions of Example V do not discolor and, or stain the copper once the material is crosslinked and likewise it is observed that the original tone of the material does not change.

As a result of these formulations applied as insulation in 22 AWG cable with reduced thickness according to the specification of RENAULT 38-05- 009J the following abrasion results are obtained (7 N applied weight, and 0.45 mm needle diameter): For this type of reduced wall cable the required value is 100 cycles; according to the result obtained in the invention the high density polyethylenes give a substantial increase in resistance to needle abrasion.

* As observed in the results obtained the inclusion of high density polyolefins with acrylic copolymers there is a substantial increase in the resistance to absorption to oils.

As a result of these formulations applied as insulation in wire 22 AWG type TXL according to the specification of FORD S97GG14401 AA the following results of resistance to oil absorption are obtained: Having described the invention, it is considered a novelty and therefore the content is claimed in the following:

Claims (2)

1. R E I V I DI C A C I O N S A polymeric composition based on crosslinkable polyolefins with high thermal coefficient of service in automotive cable which comprises a copolymer (EVA) of ethylene and vinyl ester of aliphatic carboxylic acid of 2-6 carbon atoms, in a ratio of 3% to 90 % of the vinyl ester and the rest of ethylene; the composition being characterized because it comprises a mixture of additives that increase the thermal coefficient at temperatures up to 150 ° C ± 5 ° C of service in cables and electric conductors exposed in high temperature zones of internal combustion engines and which also improve the properties of : resistance to hot oils, to abrasion, and to propagation to the vertical flame after being crosslinked said composition, being the ratio of mixtures: copolymer (EVA) up to 50 parts / 100 polymeric resin (phr), high polyethylene density up to 40 phr, copolymer of ethylene acrylate up to lOphr, halogenated compounds of octabromo tri methyl phenyl indane 0-40 phr .; (FR 1808® monomer depentabromo benzyl acrylate 0 -40 phr (FR-3025R), antimony trioxide 10 - 20 phr, magnesium hydroxide treated with alkoxysilane 0 -75 phr, silicone oil 0-3 phr, aliphatic resin STRUKTÓL TR 060 Iphr, metallic soaps of fatty acids and amides (STRUKTOL TR 016®) 0.5 phr; phenol with steric hindrance 2 phr, zinc salt 2 mercapto benzylmidazole 6 phr; coagent n, n'-m-phenylene dimaleic -, benzene 2 phr. The polymer composition of clause 1, characterized in that the copolymer (EVA) is preferably a mixture of ethylene vinyl acetate copolymer in a proportion of 3 to 45% and the remainder being ethylene with melt indices of 0.5 to 5 g /10 minutes. The polymer composition of clause 2, characterized in that the polyethylene copolymer can also be selected from: polypropylene, copolymers and terpolymer of ethylene propylene and acrylic copolymers The polymer composition of clause 1, characterized in that the halogenated compounds can also be selected from: hexabromobenzene, tetrabromobisphenol A, tetrachlorobisphenol A, tetrahydromophthalate anhydrous, hexabromo cyclodecane, octabromodiphenyl, perchloropentacyclohecane, octabromodiphenyl ether decabromodiphenyl ether, tribromo phenyl ayl ether, pentabromo ethylbenzene 2,4,6-tribromophenol, pentabromodiphenyl ether, ethylene bis (tetrabromophthalimide), anhydrous tetrachlorophthalate, poly (pentabromobenzyl) acylate, bis (dibromopropyl) ether of tetrabromobisphenol A, and Diels-Alder byproduct of hexachlorocyclopentadiene with maleic anhydride. which favor grafting in the polymer composition. The polymer composition of clause 1, characterized in that the magnesium hydroxide treated with an alkoxysilane can be selected from vinyl trimethoxyethoxysilane, phenyl tris (2-methoxyethoxy) silane, ethyl methyl tris (2-methoxyethoxy) silane, dimethyl diethoxysilane, ethyl trimethoxysilane and vinyl trimethoxysilane The polymer composition of clause 5, characterized in that vinyl trimethoxyethoxysilane and vinyl t-methoxyethoxysilane and vinyl trimethoxy silane are preferably used, wherein the proportions of the alkoxysilanes with respect to the magnesium hydroxide are in a ratio of 0.5 to 5 phr. The polymeric composition of clause 1 characterized in that the poimeric composition is crosslinked by dicumyl peroxide, 2,5- (tert-butylperoxy) -, -2,5-dimethyl hexin-3, di-tert-butylperoxide, 2,5 - (tert-butylperoxy) -2,5-dimethylhexane, and tert-butyl cumyl peroxide and preferably alpha, alpha'-bis (tert-butyl peroxide) diisopropyl benzene; with the combination of coagent compounds such as: triallyl cyanurate, triallyl isocyanurate. diallyl maleate, diallyl phthalate, pentaerythritol triacrylate, pentaerythritol tetracrylate, trimethylol propane triacrylate, tpmethylol propane, trimethacrylate, tetrethylene glycol dimethacrylate, low molecular weight polybutadiene and n, n'-m-phenylendimaleic acid (HVA-2®) in a ratio of 0.5 - 10 phr with respect to the crosslinking agent. The polymer composition of clause 1, characterized in that the process additives are fatty acids or derivatives thereof and preferably a mixture of metal soaps of fatty acids with an amide in admixture with a low molecular weight silicon oil and a Aliphatic resin wherein: The proportions employed in each system will be from fatty acid to silicone oil 1: 1 to approximately 1: 6, and preferably from fatty acid to silicone oil 1: 3. And with respect to the aliphatic resin to the fatty acid 1: 1 to about 1: 6 and preferably of hydrocarbon resin to fatty acid 1: 3. The total amount of the composition of the process additives is from 0.25 phr to 8 phr of the total poimeric composition. The polymer composition of clause 1, characterized in that the antioxidant agents used are pentaerythritol tetra bis (beta-lauryl thio propyanate) and preferably zinc salt 2 mercapto benz imidazole and propionate 2,2'-thiodiethyl bis (3,5-diterbutyl 4 hydroxyphenyl in proportions with respect to the polymer composition preferably 0.25-15 phr. The polymeric composition of clause 1, characterized in that it preferably comprises the following mixture ratio: • EVA copolymer 50 phr high density polyethylene 40 phr ethylene-acrylate copolymer 10 phr halogenated compound (FR 1808®) 40 phr antimony trioxide 20 phr , 3 phr silicon oil aliphatic resin (SYTUKTOL TR 060) I hr, 0.5 phr fatty acid metal soaps, with amide (STRUKTOL TR 016) zinc salt 2 mercaptobenzimidazole 6 phr (VULKANOX ZMB2) sterically hindered phenol 2 phr, coagent (HVA-2®) l hr, and alpha, alpha 'bis (terbutilperoxide) diisopropyl benzene 2 phr. The polymeric composition of clause 1, characterized in that it preferably comprises the following mixture ratio: • EVA 50 phr copolymer, • high density polyethylene 40 phr. • ethylene acrylate copolymer 10 phr, • halogenated compound (FR-1025 * 40 phr. • antimony trioxide 20 phr, • silicone oil 3 phr, • aliphatic resin (STRUKTOL TR 060) 1 phr, • mix of metal soaps acids l phr, fatty acids with amide • (STRUKTOL TRO 16) 0.5 phr .. • 2 2 mercaptobenzimidazo zinc salt? 6 phr, (VULKANOX ZMB2) • phenol with steric hindrance 2 phr, • coagent (HVA-2 *) 1 phr, and • alpha, alfa'bis (terbutil peroxide) 2 phr. diisopropyl benzene)
2. 2. The polymer composition of clause 1, characterized in that it preferably comprises the following mixture ratio; • 50 phr EVA copolymer, • 40 phr high density polyethylene • 10 phr ethylene acrylate copolymer, • halogenated compound (FR-1808F) 20 phr, • 10 phr antimony trioxide, • magnesium hydroxide treated with 75 phr alkoxysilane, • oil silicon 3 phr, • aliphatic resin (STRUKTOL TR060) 1 phr, • mixture of metallic soaps of acids 0.5 PHR, fatty acids with amide (STRUKTOL TRO 16) • sterically hindered phenol 2 phr, • zinc salt 2 mercaptobenzimidazole 6 phr. (VULKANOX ZMB 2) coagent (HVA-2 SN) 1 phr, alpha, alpha'bis (terbutylperoxide) diisopropyl benzene 2 phr. In order to prepare composites for polyolefins with a high thermal coefficient of service up to 150 ° C, for automotive cable clauses 1 to 12, which comprises mixing an EVA copolymer, based on a copolymer of ethylene and vinyl ester of an aliphatic carboxylic acid of C 2-6 in a ratio of 3 - 90% of the vinyl ester being the ethylene moiety, characterized in that a mixture of additives is incorporated that increase the thermal coefficient of service in the conductors and electric cables that are arranged in high temperature zones in internal combustion engines, and that also improve the resistance to hot oils, abrasion and propagation of the vertical flame, where said mixing is carried out at temperatures from 110 ° C -135 ° C for periods of 3-6 minutes, said addition of active components being based on: organic charge of halogenated compounds and antimony trioxide in a ratio of 2: 1 to 5: 1, preferably 2.5: 1 to 4: 1; interaction of vinyl alkoxysilane with the charge. .organic and polymer mixture used copolymer (EVA), high density polyethylene and ethylene acrylate copolymer, in the mixture in a ratio of 0.5 to 5 phr; addition of process additives preferably aliphatic ream, silicone oil in a ratio of 0.25 phr to 8 phr; addition of antioxidant agents, preferably zinc salt 2-mercaptobenzimidazole and 2,2'-thiodiethyl propylate bis- (3,5-diterbutyl-4-hydroxyphexyl) or penfaerythritol tetra-bis (beta-lauryl thiopropylate) in a ratio of 0.25-15 phr; after the first addition of silane, filler, polymers and addition of peroxide, - ux combination with coagents of preferably n, n'-m-phenylene dimaleic in a ratio of 0.5 - 10 phr, once all the components are added intensive mixing of the composition until total dispersion; once mixed the composition is laminated and granulated for extrusion. The process of clause 13, characterized in that the halogenated inorganic filler, are brominated compounds that do not generate toxic dioxins and furans when in combustion and are preferably used: octabromotrimethylphenyl mdane with melting temperature of 240 ° C - 256 ° C (FR) -1808 *) and pentabromo benzyl acrylate monomer with a melting point of 117 ° C - 120 ° C (FR-1025®). The method of clause 13, characterized in that the polymer component (EVA) is preferably a copolymer of ethylene and vinyl acetate in a proportion preferably of 3 to 45% of the acetate, the remainder being ethylene.