LU101658B1 - Fire resistant articles and structures - Google Patents

Abstract

A fire resistant polymeric foam article, a structure comprising the article, use of the article or structure and a method of making the article or structure, the polymeric foam comprising a) 30 to 55% by weight of a polymer composition comprising ai) a first polymer component selected from ethylene-C 1 -C 4 alkyl acrylate copolymers, ethylene-vinyl acetate copolymers, or mixtures thereof, a2) a second polymer component selected from copolymers comprising maleic anhydride functions, preferably ethylene-C 1-64 alkyl acrylate copolymers grafted with maleic anhydride, ethylene-vinyl acetate copolymers grafted with maleic anhydride, or mixtures thereof, a3) a third component polymer selected from plastomeric polyolefins, elastomeric polyolefins, ethylene homopolymers and mixtures thereof, b) 45 to 70% by weight of a flame retardant component comprising magnesium hydroxide, hydrogen aluminum hydroxide, a combination of calcium carbonate and silicone gum, or their mixtures, and optionally one or more nanoclays, c) 0.01 to 5% by weight of additives chosen from pigments, antioxidants, agents anti-UV, lubricants, the polymeric foam article having undergone crosslinking by chemical and / or physical means, the density of the foam being between 700 and 1000 kg / m3 and the percentages by weight relating to the weight of the polymer foam article.

Description

lu101658

FIRE RESISTANT ARTICLES AND STRUCTURES Technical field

The present invention relates to fire-resistant articles and structures, respectively flame retardants, which can be used in many fields, in particular for the purposes of protection against fire in construction or the automobile, for example a sheath or a plate foam, serving as protection of a pipe, of a surface, against the ignition.

State of the art | [0002] The fire behavior and especially the fire resistance are essential parameters to take into account when developing a material.

This is particularly true in the case of organic materials, such as | plastics, rubbers, organic fibers or textiles, etc., which | are used in many fields because of their many properties | advantageous physical and technical. However, it is well known that these materials are generally flammable and by nature often insufficiently | fire resistant. In order to be able to use them in many applications, they must be modified with the aim of preventing or at least retarding fire, that is to say to make them more resistant to fire. | [0003] Numerous attempts to improve the fire resistance and the fire behavior of such materials are known. In particular, we have | envisaged the use of additives such as flame retardants in these materials, if this is feasible, or even if possible the provision of additional external protection in low flammable or even non flammable materials of inorganic nature.

The addition of flame retardants in a material can in this case be considered in the case of polymer, thermoplastic or thermosetting compositions, and there are indeed many solutions of this type with more or less good performance . There are in this case different types of flame retardant, among others compounds of mineral type, halogenated compounds or phosphorus compounds.

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[0005] Although some of these compounds make it possible to significantly improve the fire behavior of polymers, they have other disadvantages. For example, among the halogenated compounds a large number exhibit high toxicity as such. In addition, halogenated compounds comprising aromatic rings can degrade to dioxins and dioxin-like compounds, when heated, during production, during a fire, during recycling, or even during exposure to the sun.

[0006] In addition, the incorporation of these agents into a composition changes the physical properties thereof and may even make the modified composition unsuitable for the intended use.

Consider an external protection which intrinsically has good fire resistance properties because of a low or non-flammable nature is unfortunately rarely feasible in practice, because the available materials of this type precisely do not very often have the desired properties of flexibility, ease of shaping, low weight, low cost, efc.

[0008] Despite the existing solutions, it therefore appears advantageous to develop alternative materials having good fire properties, respectively articles making it possible to improve the fire resistance properties of existing materials. Object of the invention

[0009] An object of the present invention is therefore to provide articles and structures having good fire resistance or fire resistance, which can be used in many fields, in particular construction and automotive. General description of the invention

In order to achieve the objective mentioned above, the present invention provides, in a first aspect, a fire-resistant polymeric foam article, the polymeric foam comprising a) 25 to 55% by weight of a composition in polymers comprising lu101658 al) a first polymer component chosen from ethylene-C1 to C4 alkyl acrylate copolymers, ethylene-vinyl acetate copolymers, or mixtures thereof, a2) a second polymer component chosen from among ethylene copolymers comprising maleic anhydride functions, preferably ethylene-C- to C4 -alkyl acrylate copolymers grafted with maleic anhydride, ethylene-vinyl acetate copolymers grafted with maleic anhydride, or mixtures thereof, a3 ) a third polymer component selected from polyolefins | plastomers, elastomeric polyolefins, ethylene homopolymers and mixtures thereof, b) 45 to 70% by weight of a flame retardant component comprising magnesium hydroxide, aluminum hydroxide, a combination | of calcium carbonate and silicone gum, or mixtures thereof, and optionally one or more nanoclays, c) 0.01 to 8% by weight of additives comprising pigments, antioxidants, anti-UV agents, lubricants, antistatic agents, nucleators of = cells, denucleators of = cells, reflectors / infrared absorbers, thermal stabilizers, metal deactivators, ... the polymeric foam article having undergone chemical crosslinking and / or physical, the density of the foam being between 700 and 1000 kg / m ° and the percentages by weight relating to the weight of the polymeric foam article (the sum of all the components representing 100% by weight of the article polymer foam).

In search of a solution integrating thermal and / or sound insulation properties with acceptable qualities of fire resistance, the inventors have identified that it is not only possible to obtain polymer foams of densities and of appropriate structure with high contents of inorganic flame retardants, but above all that the compositions indicated above have a fire resistance power, respectively to flame, which is much greater than that of known compositions, or even similar, even unfoamed ( i.e. dense). As the examples and discussion below show,

lu101658 | the results obtained are not only surprisingly good, but also counter | intuitive for those skilled in the art.

The first polymer component a1) is selected from ethylene-C4-C4 alkyl acrylate copolymers and ethylene-acetate copolymers | vinyl, that is, copolymers of ethylene with methyl (EMA), ethyl (EEA), propyl (EPA) or butyl (EBA) acrylate or | vinyl (EVA) as a comonomer. Preferably, this comonomer represents 5 to 40% by weight, in particular 10 to 35% by weight, in particular 14 to 30% by weight, particularly preferably 16 to 25% by weight of the weight of | these copolymers. The melt flow index (MFI) of the first component is generally between 0.1 and 20 g / 10 min, preferably between 2 and 10 g / 10 min (190 ° C, 2.16 kg).

The amount of the first polymer component a1) in the article according to the invention will in most cases be between 5 and 35% by weight, in particular | from 7.5 to 30% by weight, in particular from 10 to 25% by weight of the weight of the polymeric foam article. | The second polymer component a2) is chosen from copolymers | comprising maleic anhydride functions. I! can be copolymers of a | or of several monomers comprising maleic anhydride groups in the polymer chain or as side groups (grafted). The other or the others | Monomer units are, for example, ethylene, C- to C4 alkyl acrylates, vinyl acetate, etc. Preferably, the second polymer component | comprises or consists of ethylene-C4-C4 alkyl acrylate copolymers | grafted maleic anhydride, grafted ethylene-vinyl acetate copolymers [maleic anhydride, or mixtures thereof. The content of anhydride groups | maleic is generally between 0.1 and 10% by weight, in particular of | 0.5 to 5% by weight, in particular from 1 to 4% by weight of the total weight of these copolymers. The melt index (MFI or MFR) of the second component a2) is | generally between 0.15 and 200 g / 10 min, in particular between 0.5 and / 100 g / 10 min, preferably between 1 and 20 g / 10 min (190 ° C, 2.16 kg).

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[0015] The second polymer component a2) generally represents between 2 and 40% by weight, in particular from 3 to 30% by weight, in particular from 4 to 25% by weight of the weight of the polymeric foam article.

The third polymer component a3) is chosen from plastomeric polyolefins (POP), elastomeric polyolefins (POE), ethylene homopolymers and mixtures thereof. POE and POP are ethylene copolymers | with other olefins, which lie between linear low density polyethylene (LLDPE) and fully amorphous elastomers both in density and crystallinity. The density of POEs is generally between | 0.86 and 0.89 and that of POPs generally between 0.89 and 0.91 ka / m °. These polymers can be obtained by coordinative copolymerization of ethylene | in the presence of a higher α-olefin (but-1-ene, hex-1-ene, eic.), for example | by catalysis with a metallocene. The approximate comonomer composition | α-olefin typically ranges from 10 to 30% by weight. Compared to LLDPE, POP | and POE exhibit flexural modulus, tensile strength and point of | weaker fusion; they show a higher elongation (which can exceed 800%) and a higher tenacity (Harutun G. Karian, Handbook of polypropylene and ‘polypropylene composites, p. 201-204, Marcel Dekker, 2nd ed. 2009, 670 p.). Ethylene homopolymers are selected from very low polyethylenes | density (VLDPE, very low density polyethylene), linear low density polyethylenes (LLDPE, linear low-density polyethylene), metallocene-catalysed linear low-density polyethylenes (mLLDPE, metallocene linear low-density | polyethylene), low polyethylenes density, (LDPE, low-density polyethylene), medium-density polyethylenes (MDPE, medium-density polyethylene) and high-density polyethylene (HDPE, high-density polyethylene). The melt index: (MFI or MFR) of the third component a3) is generally between 0.15 and | 30 g / 10 min, in particular between 0.2 and 20 g / 10 min, preferably between 0.3 and g / 10 min (190 ° C, 2.16 kg). The amount of the third component a3) is | function of the quantity of components a1) and a2), so that the sum of | The amounts of a1) + a2) + a3) represent 30 to 55% by weight of the weight of the polymeric foam article, but at least the amount of a3) is 0.5% by weight.

[0017] The flame retardant component b) comprises aluminum hydroxide | (decomposition: 220 ° C), magnesium hydroxide (decomposition: 330-

lu101658 350 ° C) and / or a combination of calcium carbonate and silicone gum.

The flame retardant hydroxide components work in particular by releasing water at a higher temperature. These components are usually found in the form | of precipitated hydroxide particles with a high specific surface area, having an average particle diameter of less than 30 μm and preferably between

0.1 and 10 µm. These particles can optionally be coated with organic material to further improve their compatibility with the components | polymers. The incorporation of mineral additives, as is the case with the flame retardant component of the present invention, greatly interferes with foaming, not only by the fact that these particles act as an agent / nucleating agent (gas cell forming), but above all in view of their large quantity. When the flame retardant component of calcium carbonate combined | with silicone gum is exposed to fire, it forms an intumescent system | wherein the ethylene copolymers and carbonate decompose and | form a carbonaceous foam and the silicone gum decomposes and forms a | glass which stabilizes the carbonated foam. According to the invention, appropriate foaming is made possible in particular by the use of an appropriate amount; of the second polymer component a2) acting as a compatibilizer between the | polymer phase and mineral phase and on the other hand by the use of an amount | of the third polymer component a3) to counteract them; effects of high mineral contents on structural properties and | mechanical.

In an advantageous form of the invention, the proportion of component | flame retardant can be formed by up to 10% by weight of nanoclay (s), preferably from 0.1 to 6% by weight and in particular from 1 to 5% by weight relative to | by weight of the polymer foam item. It is desirable to use the; nanoclays in finely divided form, eg as particles | of an average diameter not exceeding 30 µm and preferably between 0.001 and 10 µm. Examples of suitable nanoclays are in particular natural or modified montmorillonites, for example modified with quaternary ammonium salts, such as CLOISITE 20A (Southern Clay Products, USA), natural or modified hectorites, for example DRAGONITE-HP ( Applied Minerals), etc.

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The polymeric foam article comprises as component c) from 0.01 to | 8% by weight, preferably 0.1 to 5% by weight, especially 0.5 to 3% by weight | weight of additives chosen in particular from volume stabilizers, | antioxidants, anti-UV, anti-static, dyes and pigments, fillers, anti-fogs, anti-blocks, cell size regulators, lubricants, and possibly other anti-fire agents (i.e. i.e. different from / those of flame retardant component b)).

Among the volume stabilizers useful in the context of / the invention, there may be mentioned fatty acid amides, comprising for example | stearamide, palmitamide, behenamide and their mixtures, acid amines | corresponding fatty acids, esters of glycerin and of fatty acids, comprising, for example, alpha and beta mono-esters with fatty acids, di-esters with; fatty acids, tri-esters with fatty acids, fatty acids comprising chain lengths Cs to Cx, saturated or not, and mixtures thereof, etc. | [0021] Other additives include pigments, antistatic agents, | cell nucleators, including eg talc, silica, calcium carbonate, cell denucleators, eg including oxidized polyolefin waxes, compatibilizing polar resins (other than those of | component a2)), including eg ionomers, glycidyl methacrylate copolymers, etc., infrared reflectors / absorbers, comprising for example aluminum flakes, steel flakes, black; carbon, carbon graphite, process and application antioxidants, process and application thermal stabilizers, UV absorbers / deactivators, metal deactivators, lubricants, including by | example derivatives of fluoropolymers, amides, boron nitride,; silicones, stearates, polyolefin waxes, and mixtures of one or of | several of the additives mentioned. | Additional anti-fire agents (other than component b)) can be provided in the context of component c). In this case, it may be: advantageous to additionally use organophosphorus molecules (eg 9,10- | dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) or its derivatives), the | sulfenamides and mixtures thereof.

The lu101658 | [0023] According to the applications, in particular according to the desired shape of the article in | polymer foam, the melt flow index (MFI or MFR) of the entire composition of | the article, that is to say incorporating components a), b) and c), will generally be set to a value between 0.5 and 50 g / 10 min, preferably between 1 and 30 g / 10 min , especially between 1.5 and 25 g / 10 min (190 ° C, 2.16 kg). This adjustment can be done relatively easily by varying the proportion in third component | polymer with respect to the first and second polymer components in the | limits of the total content of the article in polymer composition. | [0024] The choice of foaming agent for making the foam article | polymer is not critical. In principle, all foaming agents traditionally used for the foaming of thermoplastic polymers or | elastomers can also be used in the context of the present invention, | such as physical foaming agents, in particular foaming gases, | such as linear, branched or cyclic C, to Cs alkanes, in particular. isobutane, isopentane, neopentane, n-pentane, cyclopentane, etc., inert gases including nitrogen, CO; or Argon, the compounds | hydrofluorocarbons (HFOs), or others such as water or ethanol (if compatible | with the possible (co-) crosslinking agent), dimethyl ether, etc. These physical agents can be introduced into the extruder in gaseous, liquid form | or liquefied (under pressure). The foaming agent (s) can also | be chemical foaming agents, solid or liquid, decomposing from | less partially in gas under [effect of heat. lilies can be introduced to; feeding the extruder or injected / dosed at a certain distance from it. | These chemical agents are for example sodium carbonates, citric acid / or their combination, azodicarbonamide, azobisiso-butyronitrile, dinitroso- | pentamethylene-tetramine, 4,4 "-oxybis (benzenesulfonylhydrazide), diphenyl-; sulfone-3,3'-disulfohydrazide, benzen-1,3-disulfohydrazide, p-toluene- | sulfonylsemicarbazide, etc; or according to all the well-known embodiments of the prior art comprising, as appropriate, operations of extrusion | and / or maintaining under pressure then expansion and / or heating, etc. The foaming agents also include | syntactic agents, in particular expandable microbeads, for example EXPANCEL (Nouryon).

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It should be noted, in the context of the invention, that certain agents | necessary for foaming are not found (or not as such) in the polymeric foam article (in particular after complete degassing), but others possibly remain partially or in modified form in the polymeric foam article, resulting for example of the decomposition of the agents of | chemical foaming. These components are counted for their content in additive component c), unless explicitly stated otherwise.

[0026] According to the invention, the foam constituting the polymeric foam article has been. chemically and / or physically crosslinked. In the preparation of the polymeric foam article, the start of foaming can take place in an already | partially crosslinked with the (co) polymer (s). This measure allows p. ex. | to increase the viscosity of the composition or even to condition the regularity | and the fineness of the cellular structure finally obtained. In this case, the crosslinking continues during foaming and possibly afterwards. | However, the crosslinking can also be started during, or even: after the foaming (in particular in [association of an expanding agent: physical, that is to say active under the effect of a relaxation , such as isobutane, and a suitable crosslinking agent, for example silane). | As optional crosslinking component d), mention may be made of silane compounds and / or peroxides. Preferred silanes are vinylsilanes, in particular: vinylalkoxysilanes such as vinylirimethoxysilane (VTMOS) or | vinyltriethoxysilane (VTEOS), allylalkoxysilanes such as Pallyltrimethoxysilane | (ATMOS) or allyltriethoxysilane (ATEOS), 3-methacryloxypropyltrialkoxysilanes such as 3-methacryloxypropyltrimethoxysilane or 3-methacryloxypropyltriethoxysilane, etc. In the event that it is desired to graft the silane (s) onto the polymer resin (s) of the foamed composition, it is desirable | to produce a suitable peroxide, which will allow the vinylsilane molecules to graft onto the radicals formed by the peroxide on the chain (s) | polymer (s). Agents increasing the efficiency of grafting can be used, by | example zinc oxide (ZnO). The presence of water is essential to initiate the crosslinking reaction. Water reacts with silane groups, and forms | silanol groups. The latter may, under adequate conditions | temperature, condense and create bridges between adjacent chains lu101658 carrying silanol groups.

In order to considerably reduce the time required for the condensation of the silanol groups into a siloxane bond (Si-O-Si), crosslinking catalysts will advantageously be added, such as dioctylbis [(1- | oxododecyl) oxy] stannane, dibutyltin dilaurate or dioctyltin, dodecylbenzenesulfonic acid, etc., or mixtures thereof.

It is useful to provide for | additives to control the degree of humidity present in the composition, | which prevents too early crosslinking thereof.

These additives react faster with water than crosslinking silanes (“scorch retardants”). We will quote | for example zinc oxide (ZnO), n-octyltriethoxy-silane.

In the same | objective, care should be taken to sufficiently dry the components of the formulation to | limit the amount of moisture present during extrusion and avoid crosslinking | premature in the extruder. | Among the peroxides useful for crosslinking, there may be mentioned for example | peroxydicumyl (DCP), a, a'-bis (t-butylperoxy) -1,3-diisopropylbenzene, 2,5-: dimethyl-2,5-di-tert-butylperoxyhexane (HXA), etc, or their mixtures.

They | attack the polymer chain (s) in certain places (double bonds, tertiary carbon, ...), and the free electron formed will be able to recombine with that | of an adjacent chain, thus creating a cross-linking bridge (link) between these chains. | The foam can advantageously contain crosslinking co-agents; as (part of) crosslinking component, especially trimethacrylate | trimethylolpropane (TMPTMA), triallyl isocyanurate (TAIC), ... | [0031] It is important to note that in the context of the invention, the indication that the article contains the crosslinking components d) mentioned means in | reality that the (finished) article has undergone crosslinking in the presence of said compounds which, | depending on their nature and function, are broken down, released or fully incorporated | or partly in the polymer foam article. | [0032] Alternatively or in addition, (additional) crosslinking can be carried out on the semi-finished article by exposure to UV energetic radiation, | beta or gamma depending on the thickness of the article to be crosslinked.

Doses of irradiation | beta or gamma used will generally be 50 to 200 kGy, in particular. 100 to 150 kGy, irradiation preferably being carried out with an update

| P-NMC-048C / LU 11 | lu101658 | temperature of the polymeric foam article, especially at an article temperature of 100 to 230 ° C, for example 150 ° C or 200 ° C.

However, it is necessary to remain at a good distance from the melting temperature of the foamed composition | in order not to cause deformation of the article under the effect of its own weight, overhang, ... | In a second aspect, the invention provides a protective structure | fire protection comprising a fire resistant polymeric foam article according to | present invention.

The structure may be a planar structure, preferably a construction / fire protection plate / plate. ; automotive, the fire protection plate being adapted to be installed / on surfaces to be protected, such as walls of buildings or surfaces of | body.

Alternatively, the fire protection structure has a shape. tubular and is preferably a fire protection sleeve in the | the field of construction or the automobile.

Such a protective sheath | against fire is suitable for installation (separately) on cables and | pipes, in particular pipes for flammable fluids, in particular for | fuel lines.

In this variant, the sheath is a structure | separated from the element it is intended to protect and is applied after the manufacture of | the item in question.

If necessary or desired, the structure can nevertheless | be fixed to the element to be protected, for example by gluing or thermofusion, etc. | [0034] In another variant, the fire protection structure is a | tubular structure which forms an outer protective layer against fire on cables and pipes in the construction or automotive field, in; particularly on pipes of flammable fluids, in particular for | fuel lines.

In these variants, and unlike the variant | above, the structure is an integral part of the element it protects and is | generally applied during the manufacture of the element, for example by | in-line or co-extrusion extrusion. | A third aspect relates to the use of a polymeric foam article | resistant to fire or a fire protection structure according to the invention | as an element of fire protection in the construction industry or | automobile.

I! preferably a fire protection plate which | will be installed on surfaces to be protected, such as the walls of buildings or

| P-NMC-048C / LU 12 lu101658 body surfaces, electric coil walls, or even a sheath | protection against fire which will be installed on cables and conduits to be protected, in particular conduits of flammable fluids, in particular for | fuel lines.

| [0036] The invention also relates, in a fourth aspect, to a method | of manufacture of a fire-resistant polymer foam article, the process | comprising the following steps: (1) dosage of components a1), a2), a3), b), c) and optionally d), | premixed or individually dosed, feeding one | extruder; | (ii) plasticization and mixing of the constituents at high temperature to melt and homogenize the constituents; | (ii) homogenization of the constituents; | (iv) cooling the mass; | (v) extrusion in the open air through a die, controlled in temperature, having | a section of predefined shape, causing foam to form | polymer; | (vi) cooling the polymeric foam thus formed into a fire resistant polymeric foam article; : in which the foaming is carried out either by means of one or more agents of | chemical foaming premixed or metered in step (i) and / or (ii), or by | feeding or injecting a physical foaming agent in step (i), in step) (ii) or between step (ii) and (iii), or by a combination of the two; and wherein the crosslinking of the polymeric foam is carried out either chemically in the presence of component d) or physically by exposure to radiation | energy, preferably UV, alpha or beta, or by a combination of both. | [0037] The method can also comprise during step (vi), before the | cooling, stretching and guiding the formed foam.

} [0038] In said method, the chemical foaming agent (s) are | generally selected from solid chemical foaming agents or | liquids, preferably soda ash, citric acid or their | combination, Tazodicarbonamide, = azobisiso-butyronitrile, dinitroso-

| P-NMC-048C / LU 13 '1u101658; pentamethylene-tetramine, 4,4'-oxybis (benzenesulfonylhydrazide), diphenyl-sulfone-3,3'-disulfohydrazide, benzen-1,3-disulfohydrazide, p-toluene- | sulfonyl-semicarbazide, or combinations thereof; and / or among the agents of | liquid or gaseous physical foaming, preferably C, to Cs alkanes | linear, branched or cyclic, including isobutane, isopentane, neopentane, n-pentane, cyclopentane, inert gases including nitrogen, | CO, or argon, hydrofluorocarbon compounds, water, ethanol, | dimethyl ether, or combinations thereof.

| The thickness of the polymer foam in the articles and the structures ‘according to the invention is generally between 0.5 mm and 10 cm, or even more: depending on the applications. In protective applications in the form of a sheath or | tube or in the form of a tubular layer forming part of an element to be protected,! the thickness of the polymer foam measured in the direction of the radius of the | section of the tube or sheath is typically 0.5 to 50 mm, preferably; 1 to 10mm, particularly preferably 2 to 5mm. In) applications in planar form, for example plate, the thickness of the foam; polymer measured in the direction perpendicular or tangent to the plane of the layer | polymer foam is typically 0.5mm to 15cm, preferably 5mm | to 5 cm, particularly preferably 2 to 25 mm.

| [0040] In the context of the invention, the expression fire resistance ", | respectively "fire resistant" means on the one hand that the foam or the article | retards the spread of flame through foam or article | for a significantly longer time than through foam or | equivalent article of olefin polymers without component b). On the other hand, these | expressions also mean that the foam or article retards the propagation of a flame through the foam or article for a period of time | significantly longer than through an article of identical composition or | similar and of equal mass, but not foamed. Polymer foam articles | fire resistant properties of the invention therefore have a high flame retardant power and | the meaning of the expression "fire resistant" is equivalent to | "Flame retardant".

| In the context of the invention, the melt index (MFI or MFR) is; measured according to ASTM D1238. The percentages by weight of the components

. P-NMC-048C / LU 14 | lu101658 | polymers, flame retardant components, additives and, where appropriate,; Crosslinking components always refer to the total weight of the polymer foam article, ie all components a), b), c) and if / applicable d). The percentages by weight of (co) monomers in a polymer | refer to the weight of that polymer only.

; Examples | Compositions according to the invention which can be extruded and crosslinked in | Fire-resistant polymeric foam articles according to the process described above comprise the following components (the amounts may be varied for each component within the ranges indicated provided that the sum a) + b) + c) + d ) = 100% by weight of the article): | Component Detail Quantity polymers Quantity | a) Polymer component, | of which | al) | EMA, EEA, EPA, EBA and / or 5-35 | EVA; a2) | EBA-g-MAH evou EVA-g- 2-40 | MAH. a3) | POE and / or POE and / or PE 20,5, b} Magnesium hydroxide (s) 45-70 | and / or aluminum and / or | calcium and gum | silicone, and possibly | nano clay (s) | d) 0.2-8 crosslinking components; Particularly advantageous compositions according to the invention which can | be extruded and crosslinked into fire resistant polymeric foam articles according to | the process described above includes the following components (the; quantities may be varied for each component within the Cc ranges -

| P-NMC-048C / LU 15 lu101658 | indicated under the condition that the sum a) + b) + c) + d) = 100% by weight of | the article): | Component Detail Quantity polymers Quantity, a) Polymer component, of which | at) | EMA, EEA, EPA, EBA and / or 14-25 | EVA; a2) | EBA-g-MAH and / or EVA-g- 3,5-10 / MAH | a3) | POE and / or POE and / or PE 0.9-15; a1) + a2) + a3) 25-40 | | Magnesium hydroxide (s) 55-65 | and / or aluminum and / or | combination of carbonate | calcium and gum; silicone, and possibly | nanoclay (s) d) Crosslinking components 1,5-3; : [0044] Concrete examples of polymeric foam articles according to the invention | have the following composition: | Component | Detail Function Quantity (% in | LDPE and nucleator masterbatch 2.8 | LDPE and pigment masterbatch 0.1 | Concentrate 70% GMS Antistatic 0.7 | (ATMER 122 from CRODA) in ZELL ”

| lu101658. d) (and c)) Porous HDPE masterbatch 2.3 Î + 65% silane + peroxide mixture | graft + crosslinking catalyst + antioxidants | Cee | On the basis of these compositions, samples of tubular sheaths have | been extruded and crosslinked according to the process described above: / [0046] The fire resistance test was generally carried out according to | DIN 73379 standard, with exposure of at least 4 minutes to a flame a | 800 ° C with a circulating water pipe at a pressure of 1.5 bar. The test is | successful if no water leak is observed within 4 minutes.

| Reticulated foam sheaths, internal diameter = 8.5 mm.

; Ex. Composition Density Thickness | Result (time | (partial) kg / m? Wall (mm) | measured) | 1 EBA + 60% | 800 to 850 12 [> min, test stopped, | Mg (OH) 2 passed | 2 EBA + 60% 730 4> 8 min, test stopped, | Mg (OH) 2 passed | 3 EBA + 30% 830 4 0.54 s, test no | (comparative) | Mg (OH) succeeded | 4 EBA + 60% 780 4> 8 min, test stopped, | Successful Mg (OH) 2; 5 EBA + 33% 500 4 1.11 s, test no | (comparative) | Mg (OH) 2 passed | EBA + 60% 730 4> 8 min, test stopped, | Mg (OH) 2 + passed | silane | 7 EBA + 0% 830 4 1.11 s, test no; (comparative) | Mg (OH) passed Ee |

. P-NMC-048C / LU 17 ı lu101658

A second series of fire resistance tests was carried out according to | DIN 73379, with exposure of at least 4 minutes to a flame at | 800 ° C +/- 50 ° C with a circulating water pipe at a pressure of 5 bar. The test is successful if no water leak is observed within 4 minutes. {[0049] Crosslinked foam sheaths, internal diameter = 8.5 mm. Ex. Composition Density Thickness | Result (time (partial) kg / m? Wall (mm) | measured) 2> 6 min, test stopped, | successful 1> 8 min, test stopped, | succeeded

Claims (16)

/ P-NMC-048C / LU 18 | 10101658 | Claims | 1. A fire-resistant polymeric foam article, the polymeric foam comprising] (a) 25 to 55% by weight of a polymer composition comprising | al) a first polymer component selected from copolymers: ethylene-C4-C4 alkyl acrylate, ethylene- copolymers | vinyl acetate, or mixtures thereof, | a2) a second polymer component selected from copolymers | of ethylene comprising maleic anhydride functions, preferably ethylene-C 1 to C-alkyl acrylate copolymers, maleic anhydride grafted ethylene-vinyl acetate copolymers grafted maleic anhydride, or mixtures thereof, | a3) a third polymer component selected from polyolefins / plastomers, polyolefin elasiomers, ethylene homopolymers and mixtures thereof, | b) 45 to 70% by weight of a flame retardant component comprising magnesium hydroxide, aluminum hydroxide, a combination | of calcium carbonate and silicone gum, or mixtures thereof, and | optionally one or more nanoclays, c) 0.01 to 8% by weight of additives comprising pigments, antioxidants, anti-UV agents, lubricants, antistatic agents, cell nucleators, cell denucleators , infrared reflectors / absorbers, thermal stabilizers and / or metallic deactivators. the polymeric foam article having undergone a chemical and / or physical crosslinking, the density of the foam being between 700 and 1000 kg / m ° and the percentages by weight relating to the weight of the polymeric foam article . 2. A fire-resistant polymeric foam article according to claim 1, which has undergone crosslinking in the presence of d) 0.2 to 8% by weight of a crosslinking component comprising a chemical crosslinking agent, preferably selected from among the following. organic peroxides, vinylsilanes, allylsilanes, methacryloxypropylsilanes -— | P-NMC-048C / LU 19 | lu101658 | or their mixtures; and / or a crosslinking co-agent, preferably chosen | from trimethylolpropane trimethacrylate, triallyl isocyanurate, | zinc oxide, or mixtures thereof. 3. A fire-resistant polymeric foam article according to claim 1 or 2, | wherein the first polymer component a1) represents between 5 and 35% by weight, especially 7.5 to 30% by weight, in particular 10 to 25% by weight | weight by weight of the polymer foam article; in which the first | polymer component a1) comprises 5 to 40% by weight, in particular 10 to 35% by weight, in particular 14 to 30% by weight, particularly preferably 16 to 25% by weight of alkyl acrylate groups in C4 to C4, respectively vinyl acetate based on the weight of the first component; and / or in which the melt index of the first component a1) is between 0.1 and 20 g / 10 min, preferably between 2 and 10 g / 10 min, measured at 190 ° C, 2.16 kg, depending on the ASTM D1238 standard. 4. A fire-resistant polymeric foam article according to any of | preceding claims, wherein the second polymer component a2) represents between 2 and 40% by weight, especially 3 to 30% by weight, in particular 4 to 25% by weight of the weight of the polymeric foam article; wherein the second polymer component a2) comprises 0.1 to 10% by weight, especially 0.5 to 5% by weight, in particular 1 to 4% by weight of maleic anhydride groups based on the weight of the second polymer component; and / or in which the melt index of the second component a2) is between 0.15 and 200 g / 10 min, in particular between 0.5 and 100 g / 10 min, preferably between 1 and 20 g / 10 min , measured at 190 ° C, 2.16 kg, according to ASTM D1238. 5. A fire-resistant polymeric foam article according to any one of the preceding claims, wherein in the third component a3) the density of the elastomeric polyolefins is between 0.86 and 0.89 kg / m ° and that of the plastomeric polyolefins. between 0.89 and 0.91 kg / m®; and / or in which the melt index of the third component a3) is between 0.15 and 30 g / 10 min, in particular between 0.2 and 20 g / 10 min, preferably between 0.3 and g / 10 min measured at 190 ° C, 2.16 kg, according to ASTM D1238. 6. A fire-resistant polymeric foam article according to any preceding claim, wherein the flame retardant component b) ess | P-NMC-048C / LU 20 | lu101658 | comprises up to 10% by weight of nanoclay (s), preferably from 0.1 to 6% by weight and in particular from 0.5 to 5% by weight, based on the weight of the article | polymer foam, the nanoclays preferably being montmorillonites | or hectorites, modified or not. | 7. A fire-resistant polymeric foam article according to any preceding claim, further comprising at least one additive | selected from volume stabilizers, antioxidants, | anti-UV, anti-static, dyes and pigments, fillers, anti- | fogs, anti-blocks, permeability modifiers, size regulators | cell phone, lubricants, and possibly other different fire-fighting agents | those of flame retardant component b). | 8. A fire-resistant polymeric foam article according to any one of | preceding claims, which is a fire resistant foam sheet | or a fire resistant foam sheath. 9. Fire protection structure comprising a foam article | A fire resistant polymer according to any one of the preceding claims. 10. A fire protection structure according to claim 9 which is a planar structure, preferably a fire protection plate in the construction or automotive field, the protection plate against | the light being adapted to be installed on surfaces to be protected, such as building walls or bodywork surfaces. 11. Fire protection structure according to claim 9 which is a tubular structure, preferably a fire protection sheath in the construction or automotive field, the fire protection sheath being adapted to be. installed on cables and pipes, in particular pipes of flammable fluids, in particular for fuel pipes. 12. Fire protection structure according to claim 9 which is a tubular structure forming an outer protective layer against fire on cables and pipes in the field of construction or Ee ee ee ee | P-NMC-048C / LU 21 | lu101658 the automotive industry, in particular on flammable fluid lines, in particular for fuel lines. | 13. Use of a fire-resistant polymer foam article according to a | any of claims 1 to 8 or a fire protection structure according to claim 10 as a fire protection element in | the construction or automotive industry, preferably as | fire protection plate for installation on surfaces to be protected, such | than building walls or bodywork surfaces, ‘| electric heater, or as a protective sheath against fire to be installed on | cables and pipes to be protected, in particular fluid pipes | flammable, especially for fuel lines. | 14. A method of making a fire resistant polymeric foam article according to | any one of claims 1 to 8, the method comprising the steps | following: | (i) dosage of components a1), a2), a3), b), c) and possibly d), | premixes or doses individually, fed to an extruder; / (i) plasticization and mixing of components at high temperature for | melt and homogenize the constituents; | (iii) homogenization of the constituents; | (iv) cooling the mass; (v) extrusion in the open air through a die, controlled in temperature, having a section of predefined shape, causing the formation of a polymer foam; (vi) cooling the polymeric foam thus formed into a fire resistant polymeric foam article; in which the foaming is carried out either by means of one or more agents | premixed or dosed chemical foaming agent in step (i) and / or (ii), either by feeding or injecting a physical foaming agent in step (i), in step (ii) or between step (ii) and (iii), or by a combination of the two; and wherein the crosslinking of the polymeric foam is carried out either chemically in the presence of component d) or physically by exposure. lu101658 has energetic radiation, preferably UV, alpha or beta, or by a combination of the two. 15. The method of claim 14, wherein step (vi) further comprises stretching and guiding the foam formed. 16. The method of claim 14 or 15, wherein the chemical foaming agent (s) are chosen from solid or liquid chemical foaming agents, preferably sodium carbonates, citric acid or their combination, azodicarbonamide, azobisiso-butyronitrile, dinitrosopentamethylene-tetramine, 4,4-oxybis (benzenesulfonylhydrazide), diphenyl-sulfone-3,3'-disulfohydrazide, benzene-1,3-disulfohydrazide, p-toluenesulfonyl-semicarbazide , or their combinations; and / or liquid or gaseous physical foaming agents, preferably linear, branched or cyclic C ”to Cs alkanes, in particular isobutane, isopentane, neopentane, n-pentane, cyclopentane, inert gases , in particular nitrogen, CO, or argon, hydrofluorocarbon compounds, water, ethanol, dimethyl ether, or their combinations. rare ESS