LU101657B1 - 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 -C 4 -alkyl acrylate copolymers grafted with maleic anhydride, ethylene-vinyl acetate copolymers grafted maleic anhydride, or mixtures thereof, a3) a third polymer component 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 mixtures thereof, 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 a chemical and / or physical crosslinking, 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

lu101657

FIRE RESISTANT ARTICLES AND STRUCTURES Technical area

The present invention relates to fire-resistant articles and structures, respectively flame retardants, which can be used in many fields, in particular for purposes of protection against fire in construction or the automobile, for example a sheet of foam, serving as protection of a surface against 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 advantageous physical and technical properties. However, it is well known that these materials are generally flammable and by nature often insufficiently resistant to fire. In order to be able to use them in many applications, they must be modified in order to prevent or at least delay the 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, consideration has been given to the use of additives such as flame retardants in these materials, if this is feasible, or even to the extent possible the provision of additional external protection in low flammable or even non-flammable materials. inorganic in nature.

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

lu101657

[0005] Although some of these compounds can 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, reduced weight, favorable costs, etc.

[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 lu101657 al) a first polymer component chosen from ethylene-C4-alkyl acrylate copolymers, ethylene-vinyl acetate copolymers, or mixtures thereof, a2) a second polymer component chosen from among copolymers of ethylene comprising maleic anhydride functions, preferably copolymers of ethylene-C 1 to C 4 alkyl acrylate grafted with maleic anhydride, copolymers of ethylene-vinyl acetate grafted in maleic anhydride, or mixtures thereof, a3) a third polymer component 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, hydroxide of aluminum, 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 including pigments, antioxidants, anti-UV agents, lubricants, antistatic agents, cell nucleators, cell-denucleators , infrared reflectors / absorbers, thermal stabilizers, metal deactivators, etc. the polymeric foam article having undergone crosslinking chemically and / or physically, the density of the foam being between 700 and 1000 kg / m2 and the weight percentages relating to the weight of the polymeric foam article (the sum of all components representing 100% by weight of the polymeric foam article).

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 structure suitable 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 higher than that of known compositions, or even similar, even unfoamed (i.e. i.e. dense). As the examples and discussion below show,

lu101657 the results obtained are not only surprisingly good, but also counter / intuitive for the skilled person.

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

[0013] 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 7.5 to 30% by weight, in particular 10 to 25% by weight of the weight of the article | in polymer foam. | The second polymer component a2) is chosen from copolymers comprising maleic anhydride functions. || can be copolymers of one; or more monomers comprising maleic anhydride groups in the; polymer chain or as side groups (grafted). The other (s): monomer units are, for example, ethylene, C4 to Ca alkyl acrylates, vinyl acetate, etc. Preferably, the second polymer component | comprises or consists of ethylene-C- to C4 -alkyl acrylate copolymers grafted with maleic anhydride, ethylene-vinyl acetate copolymers grafted with maleic anhydride, or mixtures thereof. The content of maleic anhydride groups 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).

-—

lu101657

[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 polyolefins | plastomers (POP), polyolefin elastomers (POE), ethylene homopolymers and mixtures thereof. POE and POP are ethylene copolymers | with other olefins, which fall between linear low density polyethylene | (LLDPE) and totally amorphous elastomers both in terms of their density | only in terms of their crystallinity. The density of POEs is generally between | 0.86 and 0.89 and that of POPs generally between 0.89 and 0.91 kg / 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, etc.), 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 lower flexural modulus, tensile strength and melting point; they show an 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.). The 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 a function of the amount of components a1) and a2), so that the sum of the amounts of a1) + a2) + a3) represents 30 to 55% by weight of the weight of the article in | polymer foam, 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-

; lu101657 350 ° C) and / or a combination of calcium carbonate and silicone gum. | The flame retardant hydroxide components work in particular by releasing water | at higher temperature. These components are generally found in the form of particles of precipitated hydroxides with a high specific surface area, having a | average particle diameter less than 30 µm and preferably between

0.1 and 10 µm. These particles can optionally be coated with materials; organic compounds to further improve their compatibility with the polymer components. The incorporation of mineral additives, as is the case with | flame retardant component of the present invention, strongly interferes with the | foaming, not only by the fact that these particles act as an agent; nucleating agent (gas cell formator), 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 / in which the ethylene copolymers and carbonate decompose and | form a carbonated foam and the silicone gum decomposes and forms a glass which stabilizes the carbonized foam. According to the invention, a foaming; suitable 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 the effects of high mineral contents on the structural and mechanical properties.

| 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, based on the weight of the polymeric foam article. It is desirable to use the | nanoclays in finely divided form, for example in the form of particles with 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 salts | ammonium compounds, such as CLOISITE 20A (Southern Clay Products,; USA), natural or modified hectorites, for example DRAGONITE-HP | (Applied Minerals), etc.

lu101657

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

Among the volume stabilizers useful in the context of the invention, mention may be made of fatty acid amides, comprising for example stearamide, palmitamide, behenamide and their mixtures, the corresponding fatty acid amines , esters of glycerin and of fatty acid, comprising by | example alpha and beta mono-esters with fatty acids, di-esters with fatty acids, tri-esters with fatty acids, fatty acids including | lengths of Cg to Cao chains, saturated or not, and their mixtures, etc. | [0021] Other additives include pigments, antistatic agents, | cell nucleators, including, for example, talc, silica, calcium carbonate, cell denucleators, including, for example, waxes of | oxidized polyolefins, compatibilizing polar resins (other than those of component a2)), including for example ionomers, copolymers of | glycidyl methacrylate, etc., infrared reflectors / absorbers, [including, for example, aluminum flakes, steel flakes, black | carbon, carbon graphite, process and application antioxydanis, process and application heat stabilizers / stabilizers, absorbers / deactivators | UV, metal deactivators, lubricating agents, including by | example derivatives of fluoropolymers, amides, boron nitride, | silicones, stearates, polyolefin waxes, and mixtures of one or more of the additives mentioned.

[0022] Additional fire-fighting agents (other than component b)) | can be provided under component c). In this case, it may be advantageous to use in addition to organophosphorus molecules (eg 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) or its derivatives), sulfenamides and their mixtures.

lu101657

| [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, i.e. integrating 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,

in particular between 1.5 and 25 g / 10 min (190 ° C, 2.16 kg). This setting can be made from | relatively easily by varying the proportion of the third polymer component relative 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 polymeric foam article 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 1 to C 6 alkanes, in particular | isobutane, isopentane, neopentane, n-pentane, cyclopentane, etc.,; inert gases, especially nitrogen, CO; or argon, the compounds. hydrofluorocarbons (HFOs), or others like 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 or liquefied (under pressure) form. The foaming agent (s) can also be chemical foaming agents, solid or liquid, at least partially decomposing into gas under the effect of heat.

They can be fed to 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, benzene-1,3-disulfohydrazide, p-toluene- | sulfonyisemicarbazide, etc. ; or according to all modes of implementation well | known from the prior art comprising, depending on the case, extrusion operations: and / or maintaining under pressure then expansion and / or heating, etc.

Foaming agents also include syntactic agents, in particular expandable microbeads, for example EXPANCEL (Nouryon).

lu101657

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

According to the invention, the foam constituting the polymeric foam article has been chemically and / or physically crosslinked. In the preparation of the article in | polymer foam, the start of foaming can take place in an already partially crosslinked state of the (co) polymer (s). This measure allows p. ex. to increase the viscosity of the composition or even to condition the regularity and fineness of the cellular structure finally obtained. In this case ; Crosslinking continues during foaming and possibly afterwards.

[0027] However, the crosslinking can also be started during, or even after the foaming (in particular in the 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) there may be mentioned the compounds | silanes and / or peroxides. Preferred silanes are vinylsilanes, in | in particular vinylalkoxysilanes such as vinyltrimethoxysilane (VTMOS) or | vinyltriethoxysilane (VTEOS), allylalkoxysilanes such as allyltrimethoxysilane | (ATMOS) or allyltriethoxysilane (ATEOS), 3-methacryloxypropyltrialkoxy-: silanes such as 3-methacryloxypropylirimethoxysilane or 3-methacryloxypropyltriethoxysilane, etc. In the event that it is desired to graft the silane (s) | on the polymeric resin (s) of the foamed composition, it is desirable | to introduce a suitable peroxide, which will allow the vinylsilane molecules to | 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. The water reacts with the silane groups and forms silanol groups. The latter may, under adequate conditions | temperature, condense and create bridges between adjacent chains

PEER AA

/ lu101657: carriers of silanol groups. In order to considerably reduce the time required for the condensation of the silanol groups into a siloxane bond (Si-O-Si), we | will advantageously add crosslinking catalysts, such as dioctylbis [(1- | oxododecyl) oxy] stannane, dibutyltin or dioctyltin dilaurate, | dodecylbenzenesulfonic acid, etc., or mixtures thereof. It is useful to provide for | additives making it possible 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”). Mention will be made, for example, of zinc oxide (ZnO), n-octyltriethoxy-silane. For the same purpose, care should be taken to dry the components of the formulation sufficiently to: limit the amount of moisture present during extrusion and avoid premature crosslinking in the extruder.

Among the peroxides useful for crosslinking, there may be mentioned, for example, peroxydicumyl (DCP), α, o’-bis (t-butylperoxy) -1,3-diisopropylbenzene, 2,5- | dimethyl-2,5-di-tert-butylperoxyhexane (HXA), etc., or mixtures thereof. Lily ; attack the polymer chain (s) at 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 bridge (link) cross-linking between these. chains.

‘[0030] The foam may advantageously contain crosslinking co-agents: as (part of the) crosslinking component, in particular trimethacrylate | trimethylolpropane (TMPTMA), triallyl isocyanurate (TAIC),…: [0031] It is important to note that in the context of the invention, 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 decomposed, released or incorporated in whole or in part in the polymeric foam article.

Alternatively or additionally, (additional) crosslinking can be; carried out on the semi-finished article by exposure to UV, beta or gamma energy radiation 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, the irradiation preferably being carried out with a temperature setting of the polymeric foam article, in particular at a temperature of the article of 100 to 230 ° C, for example at 150 ° C or at 200 ° C. However, it is necessary to stay at a safe distance from the melting temperature of the foamed composition so as not to cause deformation of the article under the effect of its own weight, overhang, etc.

In a second aspect, the invention provides a fire protection structure comprising a fire resistant polymer foam article according to.

present invention. The structure may be a planar structure, preferably a fire protection plate in the construction or automotive field, the fire protection plate being adapted to be installed on surfaces to be protected, such as buildings. building walls or bodywork surfaces. Alternatively, the fire protection structure has a tubular shape and is preferably a fire protection sleeve in the | construction or automotive industry. Such a protective sheath: against fire is suitable for being installed (separately) on cables. In: this variant, the sheath is a structure separate from the element that it is to protect and is applied after the manufacture of the element 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 that forms an outer layer of fire protection on | cables in the construction or automotive industry. In these | variants, and unlike the previous variant, 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 extrusion or by coextrusion. | [0035] A third aspect relates to the use of a fire-resistant polymeric foam article or fire protection structure according to the invention as a fire protection element in the construction industry or | of the automobile. This is preferably a fire protection plate which | will be installed on surfaces to be protected, such as walls of buildings or | body surfaces, electric battery walls, or even a fire protection sheath that will be installed on cables to be protected.

PTE EEE re lu101657

[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: (i) dosage of the components at), a2), a3), b), c) and optionally d), premixed or individually dosed, to the feed of an extruder; | (ii) plasticization and mixing of the constituents at high temperature for | melt and homogenize the constituents; | (iii) homogenization of the constituents; (iv) cooling the mass; : (v) free air extrusion through a die, controlled in temperature, having: a section of predefined shape, causing the formation of a foam | 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 | premixed or dosed chemical foaming in step (i) and / or (ii), or by | feeding or injecting a physical foaming agent in step (i), in step | (if) 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 energetic radiation, preferably UV, alpha or beta, or by a combination of the two.

| [0037] The method can also include during step (vi), before cooling, stretching and guiding the foam formed.

In said method, the chemical foaming agent (s) are generally chosen from solid chemical foaming agents or | liquids, preferably sodium carbonates, citrus acid or a combination thereof, azodicarbonamide, [azobisiso-butyronitrile, dinitroso- | pentamethylene-tetramine, 4,4'-oxybis (benzenesulfonylhydrazide), diphenyl-: sulfone-3,3 "-disulfohydrazide, benzen-1,3-disulfohydrazide, p-toluene-sulfonyl-semicarbazide, or combinations thereof; and / or from liquid or gaseous physical foaming agents, preferably linear, branched or cyclic C; to C alkanes, in particular isobutane, isopentane,

NOT

| P-NMC-048S / LU 13 | lut01657 neopentane, n-pentane, cyclopentane, inert gases including nitrogen, CO, or argon, hydrofluorocarbon compounds, water, ethanol, | dimethyl ether, or combinations thereof.

. [0039] The thickness of the polymeric foam in articles and 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 flat form applications, eg 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. | In the context of the invention, the expression fire resistance ", | respectively "fire resistant" means on the one hand that the foam or article / retards the propagation of a flame through the foam or the joint, for a time significantly longer than through of a foam or a | equivalent article of olefin polymers without component b). On the other hand, these | expressions also mean that the foam or article retards the spread | flame through 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. The fire-resistant polymeric foam articles of the invention therefore have a high flame retardant power and | the meaning of the expression "fire resistant" is equivalent to; . "Flame retardant". ; [0041] In the context of the invention, the melt flow index (MFI or MFR) is | measured according to ASTM D1238. The percentages by weight of the components | polymers, flame retardants, additives and, where appropriate, | crosslinking components always refer to the total weight of the article in | polymer foam, ie all of the 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.

- To.

| P-NMC-048S / LU 14

| 10101657 | Examples

| Compositions according to the invention which can be extruded and crosslinked into fire-resistant polymeric foam articles according to the method described above comprise the following components (the amounts which can be varied for each component within the ranges indicated under | provided that the sum a) + b) + c) + d) = 100% by weight of the article):

Component Detail Quantity polymers Quantity

; a) Polymer component,

A of which

| al) | EMA, EEA, EPA, EBA and / or 5-35

: EVA

| a2) | EBA-g-MAH and / or EVA-g- 2-40

! MAH

| a3) | POE and / or POE and / or PE 20.5

| EEC | b) Magnesium hydroxide (s) 45-70

| and / or aluminum and / or

; combination of carbonate

| calcium and gum

, silicone, and possibly

; € | ; d) Crosslinking components 0.2-8

; 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 ranges | indicated provided that the sum of a) + b) + c) + d) = 100% by weight of | the article):

| lu101657 | Component Detail Quantity polymers Quantity TT came | es a) Polymer component, | of which al) | 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 at) + a2) + a3) 25-40: b) Magnesium 55-65 and / or aluminum hydroxide (s) and / or combination of carbonate calcium and silicone gum, and optionally | nancargile (s); ome ees d) Crosslinking components 1,5-3 CT fem I ES | I qq Total | 108

Concrete examples of polymeric foam articles according to the invention have the following composition: | Component | Detail Function Quantity (% in mT eT | CE | ws | 9 fer | | wes y [ro | oem | [5 (wk | | | oes | | | | Masterbatch of LDPE and 2.8 I rial nucleator AN LDPE and pigment 0.1 lose masterbatch TT: Concentrate of 70% GMS Antistatic 0.1 (ATMER 122 from CRODA) in | d) (and c)) Porous HDPE masterbatch 2.3 lu101657 grafting + crosslinking catalyst + antioxidants TT eee mw

On the basis of these compositions, samples of foam plagues were extruded and crosslinked according to the method described above.

Claims (16)

lu101657 Claims 1. A fire-resistant polymeric foam article, the polymeric foam comprising a) 25 to 55% by weight of a polymer composition comprising a) a first polymer component selected from ethylene-C4-alkyl acrylate copolymers. Cs, ethylene-vinyl acetate copolymers, or mixtures thereof, a2) a second polymer component chosen from ethylene copolymers comprising maleic anhydride functions, preferably ethylene-C4-alkyl acrylate copolymers. Cagrafted maleic anhydride, ethylene-vinyl acetate copolymers grafted with maleic anhydride, or mixtures thereof, a3) a third polymer component 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, aluminum hydroxide, a combination of calcium carbonate and silicone gum, or mixtures thereof, and optionally one or more several nanoclays, c) 0.01 to 8% by weight of additives including pigments, antioxidants, anti-UV agents, lubricants, antistatic agents, nucleators of = - cells, denucleators of = cells, infrared reflectors / absorbers, thermal stabilizers and / or metallic deactivators. the polymeric foam article having undergone chemical and / or physical crosslinking, the density of the foam being between 700 and 1000 kg / m? and weight percentages based on 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 lu101657 | 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 polymeric component a1) is between 5 and 35% en | 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, especially 10 to | 35% by weight, in particular 14 to 30% by weight, particularly preferably 16 to 25% by weight of alkyl acrylate groups; C- to C ,, respectively vinyl acetate relative to the weight of the first; making up ; 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, per ASTM D1238. ; 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, in particular from 3 to 30% by weight, in | in particular from 4 to 25% by weight of the weight of the polymeric foam article; ; wherein the second polymer component a2) comprises from 0.1 to 10% in | weight, especially 0.5 to 5% by weight, in particular 1 to 4% by weight in | maleic anhydride groups based on the weight of the second component | polymer; and / or wherein 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, of; preferably between 1 and 20 g / 10 min, measured at 190 ° C, 2.16 kg, according to standard | ASTM D1238. | 5. A fire-resistant polymer foam article according to any of; preceding claims, wherein in the third component a3) the | density elastomeric polyolefins is between 0.86 and 0.89 kg / m ° and that | 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; 10 g / 10 min measured at 190 ° C, 2.16 kg, according to ASTM D1238. ; 6. A fire-resistant polymeric foam article according to any of; preceding claims, wherein the flame retardant component b) ee lu101657 comprises up to 10% by weight nanoclay (s), preferably 0.1 to 6% | by weight and in particular from 0.5 to 5% by weight based on the weight of the polymeric foam article, the nanoclays preferably being montmorillonites | or hectorites, modified or not. 7. A fire-resistant polymeric foam article according to any one of | preceding claims, 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, cell size regulators, lubricants, and possibly other different anti-fire 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. the 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 fire protection plate being adapted to be installed on surfaces to be protected, such as the walls of buildings or body 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 protective sheath against; fire being adapted to be installed on cables. : 12. Fire protection structure according to claim 9 which is a: tubular structure forming an outer protective layer against fire on cables in the construction or automotive field. 13. Use of a fire resistant polymeric foam article according to one of | any of claims 1 to 8 or a fire protection structure according to claim 10 as a fire protection element in - lu101657 | the construction or automotive field, preferably as | fire protection plate to be installed 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 to protect. | 14. A method of making a fire resistant polymeric foam article according to any one of claims 1 to 8, the method comprising the following steps: | (i) dosage of components a1), a2), a3), b), c) and optionally d), | premixed or individually dosed, fed to an / extruder; Ë (ii) plasticization and mixing of the components at high temperature for | 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 the formation of a foam; polymer; | (vi) cooling the polymeric foam thus formed into an article; fire resistant polymer foam; | in which the foaming is carried out either by means of one or more agents | chemical foaming agents premixed or doses 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 by route; in the presence of component (d) or physically by exposure | to 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 agent (s) of | chemical foaming agents are selected from chemical foaming agents | solid or liquid, preferably sodium carbonates, citric acid or - TTS eae eae lu101657 their combination, azodicarbonamide, azobisiso-butyronitrile, dinitrosopentamethylene-tetramine, 4,4-oxybis (benzenesulfonylhydrazide) , diphenyl-3,3 "-disulfohydrazide, benzene-1,3-disuifohydrazide, p-toluenesulfonyl-semicarbazide, or combinations thereof; and / or liquid or gaseous physical foaming agents, preferably alkanes. C ”to Cg linear, branched or cyclic, in particular lisobutane, isopentane, neopentane, n-pentane, cyclopentane, inert gases, in particular nitrogen, CO, or argon, hydrofluorocarbon compounds, l water, ethanol, dimethyl ether, or combinations thereof.