NO821247L - PREPARATION BASED ON WATERABLE SILANE MODIFIED COPOLYMERS OF ALKYLEN-ALKYLACRYLATES - Google Patents

Description

The present invention relates to compositions based on a water-curable, silane-modified alkylene alkyl acrylate copolymer, mineral fillers and a halogenated flame retardant additive. The compositions according to the invention are particularly suitable for extrusion, intended for extrusion around electrical wires and cables and telephone wires and cables and are water-cured into cross-linked products that provide protective coatings, such as insulations etc., with great resistance to deformation and with improved flame retardant properties.

Today, protective coatings such as insulation etc. applied around wires and cables by extruding compositions containing an organic peroxide and subjecting the resulting article to elevated temperatures to cure the compositions into cross-linked products. The overall implementation commonly called peroxide curing requires careful control of the process parameters to avoid

unfavorable heat and pressure build-up in the extruder. Such excessive heat and pressure build-up results in premature decomposition of the peroxide, which in turn results in cross-linking of the composition in the extruder. Cross-linking of the composition in the extruder, commonly called "scorch", necessitates in extreme cases a stoppage of operation and cleaning of the extruder. In situations where this occurs, but is not so serious, it has been found that the lifetime of the finished coating is relatively short. In addition to the processing difficulties for peroxide curing, the peroxide coating compositions do not have the degree of deformation resistance at normal peroxide contents that many users require for insulated and sheathed wire and cable items. The present invention provides compositions, based on water-curable silane-modified copolymers, which are characterized by improved flame retardancy and increased resistance to deformation. The compositions according to the invention are particularly useful as insulation around electrical wires and cables and as casings for telephone wires and cables.

Furthermore, the compositions according to the invention allow wide limits with regard to the treatment in that the compositions can be extruded at a temperature far beyond the maximum treatment temperature used when extruding peroxide-containing compositions. Being able to be extruded at higher temperatures means that the compositions according to the invention can be extruded at higher speeds and under lower pressure and provide protective coatings with improved surface characteristics, with improved dispersion of the additives. This advantage is particularly important in highly filled compositions such as those used in flame retardant applications.

In its broadest aspect, the present invention provides compositions comprising a water-curable, silane-modified alkylene alkyl acrylate copolymer, a mineral filler and a halogenated flame retardant additive where the mineral filler is present in an amount of approx. 1 - 100% by weight, preferably approx. 20 - approx. 60% by weight; and where the halogenated flame retardant additive is present in an amount of approx. 1 - approx. 100% by weight,

and preferably approx. 10 - approx. 60% by weight.

Unless otherwise stated, the weight percentages are based on the weight of the water-curable, silane-modified alkylene-alkyl acrylate copolymer.

A preferred composition for the purposes of the invention comprises a water-curable, silane-modified alkylene alkyl acrylate copolymer, talc as a mineral filler and a halogenated flame retardant additive in which the amounts are as indicated above.

Another preferred composition comprises a water-curable, silane-modified alkylene alkyl acrylate copolymer,

a halogenated flame retardant additive and as mineral filler an oxide, hydroxide, carbonate or sulphate of calcium or magnesium in which the amounts are as indicated above.

Suitable water-curable, silane-modified alkylene alkyl acrylate copolymers can be prepared as described in the parallel application U.S. Pat. Serial no. 070,785 of August 25, 1979 by reacting an alkylene-alkyl acrylate copolymer with an organosilane in the presence of an organotitanium compound.

The water-curable, silane-modified copolymers that are produced contain units with the formulas I - III which

written below.

Formula I - alpha olefin units of formula:

wherein A is hydrogen or an alkyl residue with from 1-16 carbon atoms, these alpha-olefin units being present in the copolymers in an amount of at least 50% by weight;

at least 0.1% by weight of polymerized units containing the remainder of the formula:

Formula II

in which: B is an oxygen atom, a sulfur atom or C, is a carbon atom in the main polymer chain, R is hydrogen or a monovalent hydrocarbon residue with 1-18 carbon atoms; Q is a divalent residue such as a divalent hydrocarbon residue of 1-18 carbon atoms and is bonded to -B- and -D- via carbon atoms; D is a silicon-containing residue of the formula: wherein V is hydrogen- a monovalent hydrocarbon residue of 1-18 carbon atoms or a hydrolyzable group; and Z is a hydrolyzable group; and polymerized units of the formula: wherein, as indicated, C is a carbon atom in the main polymer chain and W is an carboxylic acid residue of 1-18 carbon atoms. A preferred copolymer is one in which B is -O-, Q is -CH2-CH2- or -CH2-CH2-CH2- and Z and V are methoxy, ethoxy or butoxy and A is alkyl, exemplified by alkyl residues for R below, or hydrogen.

Illustrative of suitable hydrocarbon residues for R are alkyl residues with 1-18 carbon atoms, preferably 1-4 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl etc.; aryl residues with 6-8 carbon atoms such as phenyl, benzyl, xylyl etc.

Examples of suitable hydrocarbon residues for Q are alkyl residues with 1-18 carbon atoms, preferably 1-6 carbon atoms such as methylene, ethylene, propylene, butylene, hexylene etc.; carboxylic acid residues with 1-18 carbon atoms and preferably 1-6 carbon atoms such as methoxymethyl, methyloxypropyl, ethyloxyethyl, ethyloxypropyl, propyloxypropyl, propyloxybutyl, propyloxyhexyl and the like; arylene residues such as phenylene etc. as well as residues with the formula:

where a and 3 are whole numbers from 1-3.

As indicated, each V may be hydrogen, a hydrocarbon residue, or a hydrolyzable group. Illustrative of suitable hydrocarbon residues are alkyl residues with 1-18 carbon atoms, preferably 1-6 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, n-hexyl, dodecyl etc.; alkoxy residues with 1-18 carbon atoms, preferably 1-6 carbon atoms, such as methoxy, ethoxy, propoxy, hexoxy, dodecyloxy, methoxyethoxy and the like; aryl residues with 6-8 carbon atoms such as phenyl, methylphenyl, ethylphenyl and the like; cycloaliphatic residues with 5-8 carbon atoms such as cyclopentyl, cyclohexyl, cyclohexyloxy etc.

As stated earlier, Z is a hydrolyzable group. among which mention should be made of carboxylic acid residues as indicated previously for V; oxyaryl residues such as oxyphenyl and the like; oxy-aliphatic residues such as oxyhexyl and the like; halogens such as chlorine and the like and other hydrolyzable groups as further described in US-PS 3,508,420.

Furthermore, W, as indicated, is an carboxylic acid residue with 1-18 carbon atoms as defined for V.

The alkylene-alkyl acrylate copolymers with which the organo-silanes are reacted to form the silane-modified copolymers are known copolymers which are produced by reacting an alkene with an alkyl acrylate. j

Suitable alkenes are ethylene, propylene, butene-1, iso-butene, pentene-1, 2-methylbutene-1, 3-methylbutene-1, hexene, heptene-1, octene-1, vinyl chloride, styrene and the like. as well as mixtures thereof.

The alkylene part in the alkylene-alkyl acrylate copolymers usually contains from and including 2 to and including 18 carbon atoms and preferably from and including 2 to and 3 carbon atoms.

Suitable alkyl acrylate monomers which copolymerize with the alkenes fall within the scope of the following formula:

in which R^ is hydrogen or methyl and R2 is alkyl with 1-8 carbon atoms. Illustrative compounds covered by this formula are: methyl acrylate, ethyl acrylate, t-butyl acrylate,

methyl methacrylate, n-butyl acrylate, n-butyl methacrylate, 2-ethylhexyl acrylate, etc. as well as mixtures thereof.

The alkylene-acrylic acrylate copolymers generally have a density (ASTMD-1505 with a conditioning as in ASTMD-14 7-72) of approx. 0.92 - 0.94 and a melt index (ASTMD-1238 of 12.08 kg/cm 2 tested pressure) of approx. 0.5 - 500 decigrams per minute.

For the purposes of the invention, the preferred copolymer generally has approx. 1-50% by weight bound alkyl acrylate, preferably approx. 2 - approx. 20% by weight bound alkyl acrylate.

Suitable monomeric organosilanes which are reacted with the alkylene-alkyl acrylate copolymers to form the water-curable silane-modified polymers fall within the scope of Formula V below:

wherein X is or and R-, is

or a mono-

valent hydrocarbon residue as indicated for R, R^ is a monovalent hydrocarbon residue as indicated for R and V, Q and Z are as defined above.

Preferred silanes fall within the scope of formula VI below:

where Ry V and Z are as previously indicated and n is an integer

from 1-18.

Examples of suitable silanes falling within the framework of formula VI are the following:

acetoxyethyltrimethoxysilane acetoxyethyltriethoxysilane acetoxyethyl-tris-(2-methoxyethoxy)silane B-methacryloxyethyltrimethoxysilane y-methacryloxypropyltriethoxysilane acetoxyethylImethyldimethoxysilane y-methacryloxypropyltrimethoxysilane acetoxypropyltrimethoxysilane acetoxypropyltriethoxysilane

γ-methacryloxypropyl-tris-(2-methoxyethoxy)silane Other suitable silanes have the formulas:

HN 2 (CH 2 ) 3 Si(OCH 3 ) 3

γ-aminopropyltrimethoxysilane

NH 2 (CH 2 ) 3 Si(OCH 3 ) 3

Y-Aminopropyltriethoxysilane

HN2(CH2)2Si(OCH3)

(3-aminoethyltrimethoxysilane

HN 2 (CH 2 ) 2 Si(OC 2 H 5 ) 3

8-Aminoethyltriethoxysilane

Suitable organotitanate compounds for catalyzing the reaction between an organosilane and an alkylene-alkylacrylate copolymer can be characterized by the following formula:

wherein each R 2 , which may be the same or different, is hydrogen or a monovalent hydrocarbon residue of 1-18 carbon atoms, preferably 1-14 carbon atoms.

Examples of suitable hydrocarbon residues are alkyl residues such as methyl, ethyl, n-propyl, isopropyl, butyl, octyl, lauryl, myristyl, stearyl etc.; cycloaliphatic residues such as cyclopentyl, cyclohexyl and the like; aryl radicals such as phenyl, methylphenyl, chlorophenyl and the like; alkaryl residues such as benzyl etc.

Titanates that fall within are particularly desirable

2

the scope of formula VII are those in which each R is alkyl of 1-18 carbon atoms, preferably 1-14 carbon atoms, exemplified by tetrabutyl titanate, tetraisopropyl titanate and the like.

Organotitanates that fall within the scope of formula VII are known compounds and can be suitably prepared as described in US-PS 2,984,641.

Other suitable titanates are organotitanium chelates such as tetraoctylene glycol titanium, triethanolamine titanate, titanium acetylacetonate, titanium lactate and the like.

The amount of silane used can vary from approx.

0.1 - approx. 10 and preferably from approx. 0.3 - approx. 5% by weight, calculated on the weight of the copolymer.

The amount of organotitanate catalyst added

to the reaction mixture is a catalytic amount sufficient to catalyze the reaction between the silane and the copolymer. A preferred amount is from approx. 0.10 - approx. 2.0% by weight, calculated on the weight of the copolymer.

The temperature at which the reaction is carried out

is not significant and can vary, appropriately from approx.

80 - approx. 300°C and preferably from approx. 150 - approx. 230°C.

The reaction can be carried out at atmospheric, superatmospheric or subatmospheric pressure, although atmospheric pressure is preferred.

Other suitable curable silane-modified alkylene-alkyl acrylate copolymers are prepared as described in co-pending application U.S. Pat. Serial no. 192,319 by reacting a mixture containing an organotitanate as described previously, an alkylene-alkyl acrylate copolymer and a polysiloxane containing repeating units of the formula:

wherein R 1 is a divalent hydrocarbon residue; each V and Z are as indicated above; c is an integer with a value from 1-18 and x is an integer with a value of at least 2, generally 2-1000 and preferably 5-25. Illustrative of suitable hydrocarbon residues for R<3> are alkylene residues with 1-18 carbon atoms, preferably 1-6 carbon atoms such as methylene, ethylene, propylene, butylene, hexylene etc.; carboxylic acid esters with 1-18 carbon atoms, preferably 1-6 carbon atoms, such as methyloxymethyl, methyloxypropyl, ethyloxyethyl, ethyloxypropyl, propyloxypropyl, propyloxybutyl, propyloxyhexyl and the like.

Polysiloxanes with repeating units falling within the framework of formula VIII can be prepared by condensation and polymerization of a silane falling within the framework of formula V in the presence of a metal carboxylate. Among suitable metal carboxylates that can be used should be mentioned dibutyl tin dilaurate, tin II acetate, tin II octoate, tin naphthenate, zinc octoate, iron 2-ethylhexoate etc. The conditions used for the production of polysiloxanes, reaction temperatures, amount of substances etc. when using metal carboxylates as catalysts are the same as described below for the use of organotitanates.

Preferred polysiloxanes for the purposes of the invention contain repeating units which fall within the scope of formula VIII and have an organotitanate bound therein. Organotitanate-modified siloxanes can be used as such for reaction with copolymers of alkylene-alkyl acrylate as will be explained below.

The preferred polysiloxanes have a viscosity of approx. 0.5 poise to approx. 150 poise, preferably approx. 1 - approx. 20 poise, as determined by a Gardner-Holt bubble viscometer at a temperature of 25°C.

At least a catalytic amount of organotitanate is used to produce organotitanate-modified polysiloxanes,

it is an amount sufficient to catalyze the condensation and polymerization reaction to give a polysiloxane. As a rule, the amount of organotitanate used is in size-

order approx. 0.001 - approx. 25% by weight, calculated on the weight of raonomer silane. It is preferred to use approx. 0.5 - approx. 5% by weight organotitanate, calculated on the weight of monomeric silane.

The temperature at which the reaction is carried out can be varied within a wide range, e.g. from approx. 0 - approx. 250°C. A temperature within the range approx. 70 - approx. 130°C is preferred. Furthermore, the reaction can be carried out using a suitable solvent, illustrated by hydrocarbon solvents such as toluene, xylene, cumene, decalin, dodecane, chlorobenzene and the like.

The reaction between the organotitanate and the monomeric silane can be carried out under atmospheric, subatmospheric or superatmospheric pressure. It is preferred to carry out the latter step of the reaction under subatmospheric pressure to allow easier removal of volatile by-products. Furthermore, the reaction is preferably carried out under the atmosphere of an inert gas such as nitrogen or argon, in order to avoid the formation of a gel due to the water sensitivity of the product.

Completion of the reaction is demonstrated by the cessation of evolution of volatiles and by the weight and volume of volatiles collected compared to the theoretical weight/volume. Alternatively, the reaction can be run to a desired viscosity level and the reactants cooled to stop the reaction.

The preparation of a silane-modified copolymer of an alkylene-alkyl acrylate is carried out by reacting a polysiloxane as described with a copolymer of an alkylene-alkyl acrylate in the presence of an organotitanate catalyst.

In those cases where the polysiloxane contains bound organotitanate, no additional organotitanate catalyst is necessary, especially when at least approx. 0.5% by weight organotitanate, calculated on the weight of the monomeric silane, was used in the production of the polysiloxane.

The amount of organotitanate catalyst added to the reaction mixture is a catalytic amount, sufficient to catalyze the reaction between the polysiloxane and the copolymer. A preferred amount is from approx. 0.001 - approx. 50% by weight, preferably from approx. 0.1 - approx. 25% by weight, calculated on the weight of the polysiloxane.

The amount of polysiloxane used can vary from 0.05 - approx. 10 and preferably from 0.03 - approx. 5% by weight, calculated on the weight of the copolymer.

The temperature at which the reaction is carried out

is not significant and can usually vary from approx. 80 - approx. 300°C and preferably from approx. 150 - approx. 230°C. The reaction can be carried out at atmospheric, sub-atmospheric or super-atmospheric pressure, although atmospheric pressure is preferred, and in the presence of solvents as described earlier.

Complete reaction is detected when viscosity changes can no longer be measured.

Recovery of the silane-modified copolymer is carried out by allowing the contents of the reaction flask to cool and discharging it into a suitable receiver for storage, preferably under the cover of an inert gas.

The reaction can be carried out in any suitable apparatus, preferably an apparatus in which the copolymer is subjected to mechanical agitation, such as a Brabender mixer, a Banbury mixer or an extruder. The polysiloxane can be added to the liquid copolymer, and the organotitanate can then be added if necessary. Alternatively, if necessary, the organotitanate can be added to the copolymer before adding the polysiloxane. Furthermore, the organotitanate and the polysiloxane can be pre-mixed and added to the polymer.

Other suitable water-curable silane-modified alkylene-alkylacrylate copolymers can be prepared by grafting a saturated silane such as vinyltrimethoxysilane, vinyltriethoxysilane, 3-methacryloxyethyltrimethoxysilane, Y-methacryloxypropyltrimethoxysilane onto an alkylene-alkylacrylate copolymer as described in US-PS 3,646,155.

As indicated earlier, the compositions according to the invention comprise a water-curable, silane-modified alkylene-alkyl acrylate copolymer, a mineral filler and a halogenated

flame retardant additive.

Illustrative of suitable mineral fillers are the following: talc, aluminum trihydrate, antimony oxide, barium sulphate, calcium silicate, molybdenum oxide, silicon dioxide, red phosphorus, zinc borate, clay, calcium or magnesium salts or bases as indicated previously and others. As indicated, the preferred mineral filler is talc, potassium or magnesium compounds per se or covered with a metal salt of a fatty acid with 8-20 carbon atoms in which the metal is from group Ia,

Ila or Ilb in Mendeleev's periodic table. Acids used to form the metal salts are saturated or unsaturated monobasic or dibasic, branched or straight-chain fatty acids with 8 - 20 carbon atoms. Examples of such acids are palmitic acid, stearic acid, lauric acid, oleic acid, sebacic acid, ricinoleic acid, palmitoleic acid etc. where stearic acid is preferred. The preferred metal salts are calcium stearate and zinc stearate.

The preferred mineral fillers can also be coated with a compatible hydrophobic material such as an organosilane, an organotitanate or a metal salt of a fatty acid as described above.

Mineral fillers can be appropriately coated using approx. 0.05 - approx. 5 parts by weight of hydrophobic material per 100 parts by weight of mineral filler, in a manner as described in US-PS 4,255,303.

Halogenated flame retardant additives used in the formulation of the composition according to the invention are well known to those skilled in the art. These flame retardant additives are halogenated (brominated, chlorinated or fluorinated) organic compounds. The preferred halogenated organic compounds are chlorinated polyethylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl chloride copolymers, halogenated paraffin and paraffin wax, chlorinated alicyclic hydrocarbons and brominated aromatic compounds. The most preferred include decabromodiphenyl oxide and compounds of the following formulas: wherein R is independently chlorine or bromine and m is an integer from 1-6, such as ethylene bis(tetrabromophthalimide).

In addition to the water-curable, silane-modified alkylene-alkylacrylate copolymer, mineral filler and flame retardant additive, the compositions according to the invention may contain additives such as carbon black, lubricants, stabilizers against ultraviolet radiation, dyes, antioxidants, smoke inhibitors, etc.

It should be understood that mixtures of mineral fillers, flame retardant additives, silane-modified alkylene-alkyl acrylate copolymer and additives can be used if desired.

Compositions according to the invention are suitably formulated by mixing in a suitable apparatus, such as a Brabender mixer or the like. as described in the examples that follow.

Curing of the compositions of cross-linked products is carried out by exposing the composition to moisture. The moisture content of the atmosphere is usually sufficient to allow curing to occur within 48 hours.

The rate of cure to the extent of 30 minutes can be accelerated by exposure to an artificially humidified atmosphere or immersion in water and heating to elevated temperatures or by exposure to steam. Generally, curing is carried out at temperatures of the order of approx. 23 — approx. 100°C and preferably approx. 70 - approx. 100°C.

Furthermore, curing can be accelerated by the use of

a silanol condensation catalyst such as dibutyltin dilaurate or an organotitanate.

The compositions according to the inventions, examples 1-7, whose formulations are described in table 1, were prepared as follows:

All components except the organotitanate,

the monomeric silane, the polysiloxane and the dibutyltin dilaurate, were mixed to homogeneity in a Brabender mixer preheated to a temperature of 160°C. After homogenization was achieved, the organotitanate, dibutyltin dilaurate and the monomeric silane or polysiloxane were added to the Brabender mixer. The mixture was heated for 30 minutes to a temperature of 160-170°C and the resulting composition containing the water-curable, silane-modified alkylene-alkylacrylate copolymer was dropped hot into a polyethylene bag and kept under an argon blanket.

samples of each composition were used to produce sample plates with dimensions approx. 7.5 cm x approx. 20

cm x approx. 3 mm in a press under the following conditions:

Pressure: 350 kg/cm<2>

Temperature: 130°C

Time cycle: 5 minutes.

Controls 1-4, peroxide-based compositions, whose formulations are described in Table 1, were prepared by mixing the components in a 40 g Brabender mixer preheated to a temperature of 120°C, for approx. 5 minutes. After the 5-minute period, the contents of the Brabender blender were poured out hot, flattened in a press and cooled.

Samples of each composition were used to produce sample plates with dimensions of approx. 7.5 cm x approx. 20 cm x approx. 3 mm, in a press under the following conditions:

Pressure 250 kg/cm<2>

Temperature 180°C

Time cycle 15 minutes

Plates of compositions 1 - 7 and controls 1 - 4 were then subjected to the following tests: Limiting oxygen index ASTMD-2863-70 Monsanto rheometer curing described in detail in

US-PS 4-018-852 Decalin extractable substances ASTMD-2765 Deformation ASTMD-6 21

For these samples, a higher rheometer value indicates that the product was cured to a higher cross-linked density; a higher value for the limiting oxygen index suggests better flame retardant properties; a lower value for decalin extractables indicates a higher degree of cross-linking; a lower value for the deformation suggests improved resistance to deformation. The values given are averages obtained by sampling two plates in each case.

Aromatic bromine as indicated in the examples has the formula:

The decabromodiphenyl oxide given in the examples contained 84% by weight bound bromine.

The polysiloxane set forth in the examples had a viscosity of 3.4 poise and a repeating unit

Example 8

A composition was extracted on a 14 AWG solid copper wire by feeding a composition as described in Example 6, except for the polysiloxane, the tetraisopropyl titanate, and the dibutyltin dilaurate to a 2\.24 to 1 (length to diameter) Royle Extruder in which the extruder was combined the original admixture a second admixture of the polysiloxane, the tetraisopropyl titanate and the dibutyltin dilaurate. The amount of the second addition was 1.4% by weight, calculated on the weight of the first. The weight ratio of polysiloxane to tetraisopropyl titanate to dibutyltin dilaurate was 24:4:1. The resulting reacted composition was extruded onto the wire under the following conditions:

Cycle 1-2 minutes

The connection temperature 190 - 200°C.

The coated wire was passed through a water bath which was at ambient temperature with the result that the composition on the wire was hardened into a cross-linked product with a thickness of approx. 0.762 mm.

Tests were carried out on the coated wire as well as on sheets formed from the material pulled from the wire. The pulled material was deformed into plates with dimensions approx. 7.5 cm x approx. 20 cm x approx. 3 mm in a press under the following conditions:

With a view to extruding the compositions according to the invention onto wires and cables, the temperatures used are generally within the range of approx. 100 - approx. 300°C and preferably 150 - 230°C.

The compositions according to the invention are described in principle for use in extrusion operations for use as cable and wire coating. It should be clear that these compositions can also be used for extruded pipes, foamed objects, injection molded objects, injection molded objects, heat shrinkable objects as well as for use in fibreglass, graphite fibres, nylon fibers and the like for "extruded foils".

Claims (27)

1. Water-curable composition, characterized in that it comprises a water-curable silane-modified alkylene-alkyl acrylate copolymer, a mineral filler and a halogenated flame retardant additive in which the mineral filler is present in an amount of approx. 1 - 100% by weight, calculated on the weight of the copolymer and the halogenated flame retardant additive is present in an amount of approx. 1 - approx. 100% by weight, calculated on the weight of the copolymer. 2. Composition according to claim 1, characterized in that the mineral filler is present in an amount of approx. 20 - approx. 60% by weight and the flame retardant additive is present in an amount of approx. 10 - approx. 60% by weight. 3. Composition according to claim 1, characterized in that the mineral filler is talc. 4. Composition according to claim 3, characterized in that the talc is coated with compatible hydrophobic material. 5. Composition according to claim 4, characterized in that the hydrophobic material is a metal salt of a fatty acid. 6. Composition according to claim 5, characterized in that the metal salt of a fatty acid is calcium stearate or zinc stearate. 7. Composition according to claim 1, characterized in that the mineral filler is an oxide, hydroxide, carbonate or sulphate of magnesium or calcium. 8. Composition according to claim 7, characterized in that the mineral filler is coated with a compatible hydrophobic material. 9. Composition according to claim 8, characterized in that the hydrophobic material is a metal salt of a fatty acid. 10. Composition according to claim 9, characterized in that the hydrophobic material is calcium stearate or zinc stearate. 11. Composition according to claim 1, characterized in that the alkylene-alkyl acrylate copolymer is an ethylene-ethyl acrylate copolymer. 12. Composition according to claim 1, characterized in that the alkylene-alkyl acrylate copolymer is an ethylene-ethyl acrylate-t-butyl acrylate copolymer. 13. Composition according to claim 1, characterized in that the silane is derived from acetoxyethyltrime toxysilane. 14. Composition according to claim 1, characterized in that the halogenated flame retardant additive is decabromodiphenyl oxide. 15. Composition according to claim 1, characterized in that the halogenated flame retardant additive is ethylene-bis-(tetrabromophthalimide). 16. Composition according to claim 1, characterized in that the flame retardant additive is an aromatic boron compound. 17. Water-curable composition comprising a water-curable silane-modified ethylene-ethyl acrylate copolymer, talc which mineral filler and a halogenated flame retardant additive in which the amounts are as specified in claim 1. 18. Water-curable composition comprising a water-curable, silane-modified ethylene-ethyl acrylate copolymer, an oxide, hydroxide, carbonate or sulfate of magnesium or calcium as mineral filler and a halogenated flame retardant additive in which the amounts are as stated in claim 1. 19. Composition according to claim 1, containing calcium carbonate as mineral filler. 20. Cross-linked product with composition as stated in claim 1. 21. Wire or cable with a coating where the composition of the cross-linked product has the composition as stated in claim 1. 22. Composition according to claim 1, characterized in that the mineral filler is a mixture of talc and an oxide, hydroxide, carbonate, sulphate of magnesium or calcium. 23. Composition according to claim 22, characterized in that the alkylene-alkyl acrylate copolymer is an ethylene-ethyl acrylate copolymer. 24. Shaped object produced from the composition according to claim 1. 25. Composition according to claim 1, characterized in that the mineral filler is a mixture of talc and antimony oxide. 26. Composition according to claim 1, characterized in that the mineral filler is a mixture of antimony oxide and an oxide, hydroxide, carbonate or sulphate of magnesium or calcium. 27. Composition according to claim 1, characterized in that the mineral filler is a mixture of talc, antimony trioxide and an oxide, hydroxide, carbonate or sulphate of magnesium or calcium.