Flexible high thermomechanical stress-resistant and fireproof halogen-free thermoplastic compositions

The present invention relates to fireproof flexible thermoplastic compositions with high thermomechanical strength, based on polyolefins with incorporated functional groups grafted by polyamide moieties, containing at least one flame retardant, especially based on ammonium and zeolite polyphosphates, and not containing halogen compounds, and plasticizers for phosphorus or red phosphorus.

[0002] These compositions are useful in the production of cables for insulating and protecting electric cables, optical fibers and for producing electrical details such as electrical connectors, as well as in electrical engineering for forming objects such as enclosures.

[0003] Thermoplastic polymers such as polyethylenes, polyamides or mixtures thereof are good electrical insulators and are easy to use. They are used for the production of shields and electrical connectors and also for cable coating. Electrical installations can be a source of short circuits and ignite, they can also come into contact with a flame, and thus ignite and extend a fire along the cable route. There are various additives to make these materials non-flammable, some based on halogen products, others without halogen. The use of halogenated additives is decreasing due to ecotoxicology and toxicology (toxicity and corrosivity of vapors emitted during fires).

[0004] According to UL 94 flame propagation tests according to ISO 1210, class V0 is the best class that corresponds to a flame-retardant material that does not produce ignited droplets during the test.

[0005] For class V1, the material is more easily ignited, but does not produce ignited drops during the test. As for class V2, apart from easier flammability than for V0, lit drops can form during the test.

[0006] For even more flammable materials, the NC value (not classified) is given.

[0007] EP 629 678 describes thermoplastic alloys, including mixtures of polyamide and polypropylene, to which zeolite and ammonium polyphosphate (dehydrating agent) are added to render them non-flammable. Mixtures of polyamide and polyolefin are formed (by weight) of 57% polyamide 6 (PA 6), 33% propylene homopolymer and 10% polypropylene grafted by maleic anhydride, then condensed with polyamide monoamine oligomer. 30 parts (by weight) of ammonium polyphosphate (APP) and 1 part of zeolite were added to 69 parts of previous mixtures, followed by injection of 3.2 mm thick samples. UL 94 flame propagation tests were carried out on these samples according to ISO 1210, class V0 was obtained. V0 is the best class according to this test. These mixtures, which are formed from a PA matrix, do not contain a phosphor plasticizer and no mechanical properties are given, in particular elongation at break.

[0008] EP 704 489 describes compositions formed from a polyamide matrix in which spheres of cross-linked polyolefin are dispersed and fire retardants selected from magnesium hydroxide, decabromodiphenyl ether, melamine cyanurate and pentaerythritol. These compositions are useful for coating electric cables. They do not contain polyphosphates, phosphate plasticizers or zeolite.

[0009] However, the achieved fire resistance results of these prior art compositions are usually obtained to the detriment of the ductility of the materials (significant loss of elongation at break, breakable nature at impact at ambient temperature). In addition, it is stated that stability

The thermal performance of these materials was insufficient. By thermal stability is meant the preservation of mechanical properties (and more particularly elongation at break) after various thermal aging treatments (e.g. 1 week at 120 ° C in hot air).

[0010] EP 1 375 594 of the applicant describes flame retardant compositions without halogen compounds, comprising by weight, with 100 parts in total:

- 50 to 75 parts of a mixture of polyamide (A) and polyolefin (B), including (i) high density polyethylene (HDPE) and (ii) a mixture of polyethylene (C1) and polymer (C2) selected from elastomers, very low density polyethylenes and ethylene copolymers, wherein the mixture (C1) + (C2) is co-grafted with unsaturated carboxylic acid,

- 25 to 50 parts of a mixture consisting of:

- 0.1 to 48.8 parts of a flame retardant, of the type ammonium polyphosphate,

- 0.1 to 30 parts of phosphor plasticizer,

- 0.1 to 10 parts of zeolite.

[0011] These compositions represent class V0 or V1 according to UL 94 when the fire test is performed on 1.6 mm thick samples and their elongation at break measured according to ISO R 527-1B exceeds 100%.

[0012] In the mixture (A) + (B), 60 to 70% by weight of the polyamide (A) which forms the matrix is ​​found.

[0013] These formulations contain a phosphor plasticizer, wherein the atomic phosphorus component is known to impart flame retardancy to materials. However, it can be stated that these plasticizers, as small particles, tend to leave the resulting material (for exudation), which is not acceptable for the intended applications. So new formulations have now been found (non-exaggerated) that nevertheless have the same level of fire resistance.

[0014] Anyway, halogen-free flame retardant polyolefin with functional groups is well known in particular for use in cable production. It involves the introduction of very large amounts (60 to 65% by weight) of hydrated fillers, such as aluminum trihydrate (ATH) or magnesium dihydroxide (MDH), to ensure the expected levels of fire resistance.

Transfer of such fire resistance regulations to materials of the ethylene - alkyl (meth) acrylate copolymer type PA maleic anhydride, of the type material described in WO 02/28959 of the applicant, which relates to a mixture of a polyamide block graft copolymer formed from a polyolefin backbone and an average of at least one implanted polyamide, and from flexible polyolefin, leads to catastrophic loss of mechanical properties of the composition, in particular in terms of elongation at break (value <100%).

[0015] Furthermore, such a PA grafted copolymer does not exhibit any flame propagation resistance (UL94 test: NC = not classified for Lotader® 3410-g-PA6).

[0016] Well, certain applications envisaged for these materials (cable production, electrical and electrotechnical details, cars) require a combination of such properties.

[0017] The aim of the invention is to find compositions based on polyolefins with functional groups, grafted by polyamides, flame-retardant without halogen, which make it possible to make a material with good behavior in terms of flame propagation resistance (according to UL94 test), but also having mechanical and thermomechanical properties at a good level as well

Good thermal stability and satisfactory rheology (without obtaining excessive viscosity, MFI (Melt flow Index) high), without producing exudation in the materials obtained.

[0018] Good mechanical and thermomechanical properties are understood to mean material having a bending modulus equal to or lower than 400 MPa at ambient temperature and a modulus of elasticity, measured by dynamic mechanical analysis (DMA), at least 0.5 MPa at 150 ° C . DMA analysis involves dynamic stretching (1 Hz) of the analyzed material in the temperature range from -100 ° C to 250 ° C at a speed of 3 ° C / min and recording the values ​​of elasticity and loss modules, as well as their ratio corresponding to the loss angle tangent.

[0019] It is likewise noted that the material exhibits good thermal stability, since it maintains within 70% its initial mechanical elongation at break and breaking stress after aging under heat-oxidative conditions.

[0020] The rheology of the material in question is furthermore rated as satisfactory because it is compatible with the usual methods of processing materials of the composition of the invention (extrusion, injection ...).

[0021] According to the invention, flame retardant flexible thermoplastic compositions not containing a halogen compound are obtained, comprising a polyamide block grafted copolymer formed from a main polyolefin chain and on average at least one implanted polyamide in which the implanted components are bound to the main chain by unsaturated monomer residues ( X) having a functional group capable of reacting with an amino-terminated polyamide, unsaturated (X) monomer residues are attached to the main chain by grafting or copolymerization from their double bond, characterized in that they contain in a mixture:

- 50 to 70% by weight of a copolymer grafted with polyamide blocks,

- 25 to 35% by weight of a flame retardant selected from among phosphates, phosphinates, pyrophosphates and ammonium polyphosphates,

- about 2% by weight of a molecular sieve, such as zeolite.

[0022] Preferably according to the invention, the X-containing main polyolefin chain is selected from ethylene-maleic anhydride and ethylene- (meth) acrylate-maleic anhydride copolymers.

[0023] Preferably, there are on average at least 1.3 moles X bound to the main polyolefin chain.

[0024] In particular, the implanted polyamide has an Mn molecular mass between 1000 and

5000 g / mol and preferably between 2000 and 3000.

[0025] More specifically, the fire retardant is ammonium polyphosphate.

[0026] According to a preferred embodiment, the composition further comprises at least one copolymer of ethylene and ethylene comonomer and an ester comonomer with an unsaturated ethylene bond or carboxylic acid.

[0027] Preferably the composition according to the invention does not comprise either a phosphor plasticizer or red phosphorus.

[0028] The flame retardant thermoplastic compositions of the invention may further comprise a mixture of melamine cyanurate and / or pentaerythritol.

[0029] Furthermore, the scope of the present invention will not be exceeded if all or part of the main polyolefin chain and / or implanted polyamide elements are replaced by their respective mixture with nanofillers (such as in particular nanoclays or nanotubes with

EP 2 029 672 B1), said mixtures being known to those skilled in the art as nanocomposites.

[0030] The fireproof compositions of the invention find advantageous applications in the production of cables as well as electrical products such as electrical connectors or in electrical engineering for forming products such as enclosures.

[0031] However, these compositions can also be used to make coating layers or coats for thermal protection of lines (or conduits) for transferring fluids in the automotive industry (in particular fuel or coolant).

[0032] As for the polyamide block grafted copolymer, it can be obtained by reacting the amino terminated polyamide with the residues of the unsaturated monomer X, which are bonded by grafting or copolymerization to the main polyolefin chain.

[0033] This monomer X may for example be an unsaturated epoxy or anhydride of an unsaturated carboxylic acid. The unsaturated carboxylic acid anhydride can be selected, for example, from maleic, itaconic, citraconic, allylsuccinic anhydride, cyclohex-4-ene1,2-dicarboxylic, 4-methylenecyclohex-4-ene-1,2-dicarboxylic, bicyclo (2,1.1) hept-5-ene-2,3-dicarboxylic, and x-methylbicyclo (2,2,1) hept-5-ene-2,2-dicarboxylic acid. Preferably, maleic anhydride is used. The scope of the invention is not exceeded by replacing all or part of the anhydride with an unsaturated carboxylic acid, such as, for example, (meth) acrylic acid.

As regards the main polyolefin chain, polyolefin is referred to as an alpha-olefin or diolefin homopolymer or copolymer, such as, for example, ethylene, propylene, butene-1, octene-1, butadiene.

Examples include:

- polyethylene homopolymers and copolymers, in particular LDPE, HDPE, LLDPE (linear low density polyethylene or low density polyethylene), VLDPE (very low density polyethylene or metallocene polyethylene);

- propylene homopolymers or copolymers;

- ethylene / alpha-olefin copolymers such as ethylene / propylene, EPR (abbreviation ethylene-propylene-rubber) and ethylene / propylene / diene (EPDM);

- styrene / ethylene-butene / styrene (SEBS) block copolymers, styrene / butadiene / styrene (SBS), styrene / isoprene / styrene (SIS), styrene / ethylene-propylene / styrene (SEPS);

- copolymers of ethylene with at least one product selected from salts or esters of unsaturated carboxylic acids, such as alkyl (meth) acrylate (e.g. methyl acrylate), or vinyl esters of saturated carboxylic acids such as vinyl acetate, where the comonomer content can reach % by weight.

Preferably, the main polyolefin chains to which the X residues are attached are polyethylenes grafted by X or ethylene and X copolymers, which are obtained, for example, by radical polymerization.

[0036] As for polyethylenes on which X has been grafted, polyethylene means homo- or copolymers. [0037] As comonomers, there may be mentioned:

alpha-olefins, preferably having from 3 to 30 carbon atoms. Examples are listed above. These alpha-olefins can be used alone or in a mixture of two or more than two,

EP 2 029 672 B1

- unsaturated carboxylic acid esters, such as, for example, alkyl (meth) acrylates, where the alkyl may contain up to 24 carbon atoms, examples of alkyl acrylate or methacrylate are especially methyl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2- acrylate ethylhexyl

- vinyl esters of saturated carboxylic acids, such as, for example, vinyl acetate or propionate.

- dienes, such as, for example, 1,4-hexadiene.

- polyethylene may include several previous comonomers.

Preferably, the polyethylene, which may be a mixture of several polymers, comprises at least 50% and preferably 75% (molar) of ethylene, its density may be between 0.86 and 0.98 g / cm³. The MFI (viscosity index at 190 ° C, 2.16 kg) is preferably between 20 and 1000 g / 10 min.

[0039] Examples of polyethylenes include:

- low density polyethylene (LDPE)

- high density polyethylene (HDPE)

- low density linear polyethylene (LLDPE)

- very low density polyethylene (VLDPE)

- polyethylene obtained by metallocene catalysis,

- EPR elastomers (ethylene-propylene-rubber)

- EPDM elastomers (ethylene-propylene-diene)

- a mixture of polyethylene with EPR or EPDM

- ethylene- (meth) acrylate copolymers which may contain up to 60% by weight of (meth) acrylate and preferably 2 to 40%.

[0040] Vaccination is an operation known as such.

[0041] As for the ethylene and X copolymers, i.e. those in which X is not grafted, these are copolymers of ethylene, X and optionally another monomer that can be selected from the comonomers mentioned above for the ethylene copolymers to be grafted.

[0042] Preferably, ethylene-maleic anhydride copolymers and ethylene- (meth) acrylate-alkyl maleic anhydride are used. These copolymers comprise from 0.2 to 10% by weight of maleic anhydride, from 0 to 40%, and preferably from 5 to 40% by weight of alkyl (meth) acrylate. Their MFI is between 5 and 100 (190 ° C-2.16 kg). Alkyl (meth) acrylates have already been described above. The melting point is between 80 and 120 ° C.

[0043] Preferably there are on average at least two X moles per chain, associated with the main polyolefin chain and preferably from 2 to 5. The skilled person can easily determine by IRTF the number of these X moles. For example, if X is maleic anhydride and Mw = 95,000 g / mole of polyolefin has been found to correspond to an anhydride content of at least 1.5% by weight of the total X-containing main chain polyolefin, preferably from 2.5 to 4%. These values ​​related to the mass of amino-terminal polyamides determine the ratio of polyamide and main chain in the polyamide-grafted copolymer.

As regards the polyamide with an amino terminus, polyamide means the condensation products of: one or several amino acids, such as aminocaproic, amino-7-heptanoic, amino-11undecanoic and amino-12-dodecanoic acids, one or several lactams, such as caprolactam, enantolactam and lauryl lactam;

- one or more salts or mixtures of diamines, such as hexamethylenediamine, dodecamethylenediamine, metaxylylenediamine, bis-p-aminocyclohexylmethane and trimethylhexamethylenediamine with diacids,

EP 2 029 672 B1 such as isophthalic, terephthalic, adipic, azelaic, suberic, sebacic and dodecanedicarboxylic acid;

- or mixtures of several monomers, which leads to copolyamides.

[0045] Mixtures of polyamides may be used. Preferably PA 6, PA 11, PA 12, copolyamide with moieties 6 and moieties 11 (PA 6/11), copolyamide with moieties 6 and moieties 12 (PA 6/12) and copolyamide based on caprolactam, hexamethylenediamine and adipic acid ( PA 6 / 6-6).

[0046] The degree of polymerization can be varied within a wide range according to its value, it is a polyamide or a polyamide oligomer. The words for implanted elements are still used without distinction.

[0047] For the polyamide to have a monoamine tip, it is sufficient to use a chain stopper with the formula

Rl ~ ΝΗ₂ wherein:

R1 is hydrogen or a linear or branched alkyl group containing up to 20 carbon atoms,

R2 is a group containing up to 20 carbon atoms, a linear or branched alkyl or alkenyl group, a saturated or unsaturated cycloaliphatic group, an aromatic group or a combination of the previous ones.

The limiter may be, for example, laurylamine or oleylamine.

[0048] Preferably, the amino-terminated polyamide has a molecular weight comprised between 1000 and

5000 g / mol and preferably between 2000 and 3000.

[0049] Preferred amino acid or lactam monomers for the synthesis of the monoamine oligomer of the invention are selected from caprolactam, amino-11-undecanoic acid or dodecalactam. Preferred monofunctional polymerization limiters are laurylamine and oleylamine.

[0050] The polycondensation as defined above takes place according to methods generally known, for example at a temperature generally between 200 and 300 ° C, under reduced pressure or in an inert atmosphere, while stirring the reaction mixture. The average oligomer chain length is determined by the initial molar ratio between the polycondensable monomer or lactam and the monofunctional polymerization delimiter. To calculate the average chain length, one chain delimiter molecule is usually counted per oligomer chain.

[0051] The addition of the polyamide monoamine oligomer to the X-containing main polyolefin chain occurs by reaction of the oligomer's amino function with X. Preferably, X carries an anhydride or acid functional group, thereby forming amide or imide bonds.

[0052] The addition of the amino terminus oligomer to the X-containing main polyolefin chain is preferably carried out in a molten state. In this way, the oligomer and main chain can be mixed in the extruder at a temperature usually comprised between 230 and 300 ° C. The average residence time of the melt in the extruder can be between 5 seconds and 5 minutes, and preferably between 20 seconds and 1 minute. The efficiency of this addition is assessed by the selective extraction of free polyamide oligomers, i.e. those that have not reacted to form the final polyamide block grafted copolymer.

[0053] The production of such amino-terminated polyamides, as well as their addition to the X-containing polyolefin backbone, is described in US Patent Nos. 3,976720, US

3963799, US 5342886 and FR 2291225.

[0054] The graft copolymers of the polyamide blocks of the present invention are characterized by a nanostructured organization with polyamide plates having a thickness between and 50 nanometers.

[0055] Preferably the proportion of polyamide block grafted copolymer is from 15 to 50% to 85 to 50%, respectively, of the flexible polyolefin.

[0056] The mixtures according to the invention have very good creep resistance at temperatures at least equal to 80 ° C and can reach up to 130 ° C, that is, they do not show a break at 25 kPa.

[0057] The mixtures according to the invention can be prepared by melt mixing in extruders (single or twin screw), BUSS kneaders, BRABENDER mixers and generally conventional thermoplastic polymer mixing equipment, preferably co-rotating twin screw extruders. The mixtures according to the invention may also include liquefying agents such as silica, ethylene bis-amide, calcium stearate or magnesium stearate. They may also include antioxidants, anti-UV agents, inorganic fillers and color pigments.

[0058] The mixtures according to the invention can be prepared in one step in an extruder. The first zones are introduced with the main chain containing X (for example, an ethylene- (meth) acrylate alkyl maleic anhydride copolymer), an amide-terminated polyamide, then into some zones further a flame retardant by side introduction. You can also enter all ingredients into the first zone of the extruder.

[0059] As for the flame retardant, they are compounds capable of forming acids such as H3PO4 (orthophosphoric acid), (HPO3) n (metaphosphoric acid) and H4P2O7 (pyrophosphoric acid) when ignited. To illustrate such agents, mention may be made of ammonium phosphates, phosphinates, pyrophosphates and polyphosphates, melamine phosphates, melamine phosphite, piperazine phosphite and diphosphite, guanazole phosphate, melamine pyrophosphate and piperazine pyrophosphate.

Preferably, ammonium polyphosphates are used, which are straight chain polymers with the general formula (NH4) n + 2 PnO3n + 1, wherein n is an integer equal to or greater than 2.

[0061] Ammonium polyphosphate may be encapsulated in a melamine-based resin. The scope of the invention will not be exceeded by the use of a mixture of the previously mentioned fire retardants. The fire retardant may have functional groups introduced, for example, it may carry silane functional groups.

[0062] As for zeolites, they are described in ULLMANN'S Encyclopedia of Industrial Chemistry, 1996, 5th edition, volume 28, pages 475-504. Zeolites type A, X, Y, L, ZSM, ZM or natural zeolites such as chabazite, mordenite and fojazite can be used. Preferably, zeolites of type 3A, 4A, 5A, 10X and 13X are used. The scope of the invention will not be exceeded if a mixture of these different zeolites is used.

[0063] Zeolites are usually used in powder form above 1 μm and preferably between 2 and 50 μm. [0064] The scope of the invention will not be exceeded by replacing these zeolites with inorganic additives known as "acid catchers" or hydrotalcites. For example, DHT 4A from KYOWA can be mentioned

Chemical.

[0065] Particularly preferably, the composition of the invention may also comprise at least one copolymer of ethylene and an ethylenically unsaturated ester or carboxylic acid comonomer copolymer.

Preferably, this comonomer of the ethylenically unsaturated ester or carboxylic acid comonomer is present in a ratio of 5 to 40 mole%, preferably 15 to 35 mole% to the total amount of mole of the copolymer.

[0067] This comonomer may include at least one component selected from vinyl acetate (VA), ethyl acrylate (EA), methyl acrylate (MA), n-butyl acrylate (BA), isobutyl acrylate, methyl methacrylate, 2-ethylhexyl acrylate ( AE2H or EH), acrylic acid and methacrylic acid.

[0068] Preferably, this copolymer of ethylene and ethylenic acid or carboxylic acid unsaturated ester comonomer is introduced in a ratio that can reach 20 parts per 100 parts of the composition of the invention.

[0069] In addition to the products mentioned above, any halogen-free additive well known to the person skilled in the polyamide field can be added, such as melamine cyanurates, pentaerythritol, and silicone or fluorinated anti-drop formers. Such additives are added in a ratio that can reach up to 20% by weight of the total composition.

[0070] The compositions of the invention may further comprise at least one additive selected from dyes, pigments, optical brighteners, antioxidants, UV stabilizers and heat stabilizers.

[0071] The compositions of the invention are made either by mixing all ingredients (copolymer, fire retardant, zeolite) in a method called "direct", or by adding the fire retardant and zeolite to an already prepared mixture of copolymer and PA (the so-called "recovery").

Preparation of the formulation mix:

[0072] The formulations described below are prepared by mixing the ingredients by means of a ZSK 40 co-rotating twin screw extruder from COPERION Werner and Pfleiderer® (a method called "twin screw" marked in the table hereinafter "D.vis") in which the sheath elements are heated according to a flat profile convex at 240 ° C; the rotation speed is 300 rpm with a flow rate of 70 kg / hour; additives are added by lateral introduction to the polymer melt on the shell 4.

[0073] Another method of mixing the ingredients uses a kneader (French: co-malaxeur) BUSS type PR46 (a method called "kneading" indicated in the table "co-painting"). For this method called "kneading", the metal temperature profile is 220/250/250/250/240; the kneading rotation speed is 280 rpm and the flow rate set at 15 kg / hour, with half the fire retardant filler being introduced with the polymers into the first well, then the other half into the second well, degassing being used in the third well.

Materials used:

[0074]

Lotader® 3410: Terpolymer of ethylene, butyl acrylate (18% by weight) and maleic anhydride (3% by weight) produced by ARKEMA showing a melt flow index WSP (English: MFI) (190 ° C, 2.16 kg, measured according to ISO 1133) 5 g / 10 min.

Lotader® 6200: Terpolymer of ethylene, ethyl acrylate (6.5% by weight) and maleic anhydride (2.8% by weight) produced by ARKEMA showing WSP (190 ° C, 2.16 kg, measured according to ISO 1133) 40 g / 10 min.

EP 2 029 672 B1

Lotader® 8200: Terpolymer of ethylene, ethyl acrylate (6.5% by weight) and maleic anhydride (2.8% by weight) produced by ARKEMA showing WSP (190 ° C, 2.16 kg, measured according to ISO 1133) 200 g / 10 min.

Lotader® 7500: Terpolymer of ethylene, ethyl acrylate (17.5% by weight) and maleic anhydride (2.8% by weight) produced by ARKEMA showing WSP (190 ° C, 2.16 kg, measured according to ISO 1133) 70 g / 10 min.

Lotader® 3210: Terpolymer of ethylene, butyl acrylate (6% by weight) and maleic anhydride (3% by weight) manufactured by ARKEMA showing WSP (190 ° C, 2.16 kg, measured according to ISO 1133) 5 g / 10 min.

Evatane® 2403: A copolymer of ethylene and vinyl acetate (24% by weight) produced by ARKEMA showing WSP (190 ° C, 2.16 kg, measured according to ISO 1133) 3 g / 10 min.

Lotryl® 35BA40: A copolymer of ethylene and butyl acrylate (35% by weight) showing WSP (190 ° C, 2.16 kg, measured according to ISO 1133) 40 g / 10 min.

Lotryl® 30BA02: A copolymer of ethylene and butyl acrylate (30% by weight) showing WSP (190 ° C, 2.16 kg, measured according to ISO 1133) 2 g / 10 min.

PA6: Polyamide 6 terminated by an amine functional group with an Mn equal to 2500 g / mol, measured by

GPC.

Irganox 1098: Thermal stabilizer type "phenol full", manufactured by CIBA.

Irganox 1010: Thermal phenol filler, manufactured by CIBA.

Irgafos 168: Phosphite type thermal stabilizer, manufactured by CIBA.

Siliporite® NK10AP: 4A zeolite molecular sieve, manufactured by CECA.

Exolit® AP750: Ammonium polyphosphate produced by CLARIANT and showing a phosphorus content of 21% and a nitrogen content of 12%.

Budit® 3167: Ammonium polyphosphate produced by BUDENHEIM and showing 50% P2O5 and 21% nitrogen.

Phosphlex® 31L: Isopropylphenyl and diphenyl phosphate manufactured by AKZO.

PER: Monopentaerythritol produced by CELANESE.

Magnifin H5: Magnesium dihydroxide manufactured by MARTINSWERK.

Magnifin H5KV: Magnesium dihydroxide produced by MARTINSWERK.

Stavinor CA PSE: Calcium stearate manufactured by CECA.

Characterization of the materials [0075]

Extrusion of belts: Granules derived from "twin screw" synthesis and "kneading" methods are formed by a ThermoHaake Rheocord System 40 laboratory twin screw extruder equipped with a flat film; wherein the extruder is heated at 210 ° C to make strips from which the samples needed to characterize the materials will be cut.

MFI measurement: It is made according to ISO 1133 standard under the following conditions (230 ° C, 2.16 kg), except where otherwise mentioned.

Measurement of creep resistance: Samples cut from the above tapes are subjected to a mass corresponding to a pressure of 2 bar in a temperature-controlled dryer. The test is considered positive if the sample withstands 15 minutes under this load and the maximum temperature withstand is recorded. If the sample does not withstand these conditions, the time at which the sample will break off is measured.

EP 2 029 672 B1

Elongation and breaking stress: Measured according to ISO 527: 93-1BA on samples cut from the above straps.

Hardness: Measured on the Shore D scale according to ISO 868.

Oxygen limit factor (ILO): Measured according to ISO 4589.

Resistance to flame propagation: Measured with a test called "UL94" according to ISO 1210.

Sweating: Observation with yes or no (O / N) note.

[0076] The results of the compositions of the invention (examples 1 to 5) and compositions of the prior art (comparative examples CE1-CE9) are summarized in table 1 below:

EP 2 029 672 B1

Table 1

<td>Examples</td><td> 1</td><td> 2</td><td> 3</td><td> 4</td><td> 5</td><td>EC1</td><td>EC2</td><td>EC3</td><td>EC4</td><td>EC5</td><td>EC6.</td><td>EC7</td><td>EC8</td><td>EC9</td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Way</td><td>D. vis</td><td>D. vis</td><td>D. vis</td><td>D. vis</td><td>D. vis</td><td>co-mal</td><td>co-mal</td><td>co-mal</td><td>co-mal</td><td>co-mal</td><td>.ko-mal</td><td>co-mal</td><td>co-mal</td><td>D. vis</td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>EVATANE 2403</td><td></td><td></td><td></td><td> 13,4</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Lotryl 35BA40</td><td></td><td></td><td></td><td></td><td></td><td> 17,5</td><td></td><td></td><td></td><td> 18</td><td> 18</td><td></td><td></td><td></td>

<td>Lotryl 30BA02</td><td></td><td></td><td></td><td></td><td></td><td></td><td> 18</td><td> 18</td><td> 18</td><td></td><td></td><td> 16</td><td> 14</td><td></td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Lotader 8200</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td> 21,6</td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Lotader 7500</td><td></td><td></td><td></td><td></td><td></td><td></td><td> 21,6</td><td></td><td></td><td> 21,6</td><td></td><td> 19,2</td><td> 16,8</td><td></td>

<td>Lotader 6200</td><td></td><td></td><td></td><td></td><td></td><td> 20,8</td><td></td><td></td><td> 21,6</td><td></td><td> 21,6</td><td></td><td></td><td></td>

<td>Lotader 3410</td><td> 53,6</td><td> 49,6</td><td> 56</td><td> 42,9</td><td> 53,6</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td> 48,2</td>

<td>PA6</td><td> 13,4</td><td> 12,4</td><td> 14</td><td> 10,7</td><td> 13,4</td><td> 5,2</td><td> 5,.4</td><td> 5,4</td><td> 5,4</td><td> 5,4</td><td> 5,4</td><td> 4,8</td><td> 4,2</td><td> 12</td>

<td>Exolit AP750</td><td> 30</td><td> 35</td><td> 25</td><td> 30</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Budit 3167</td><td></td><td></td><td></td><td></td><td> 30</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td> 27</td>

<td>Magnifin H5KV</td><td></td><td></td><td></td><td></td><td></td><td> 55</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Magnifin H5</td><td></td><td></td><td></td><td></td><td></td><td></td><td> 55</td><td> 55</td><td> 55</td><td> 55</td><td> 55</td><td> 60</td><td> 65</td><td></td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Phosphlex 31L</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td> 10</td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Siliporite NK10AP</td><td> 2</td><td> 2</td><td> 2</td><td> 2</td><td> 2</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td> 1,8</td>

<td>PER</td><td></td><td></td><td> 2</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Irganox 1098</td><td> 0,5</td><td> 0,5</td><td> 0,5</td><td> 0,5</td><td> 0,5</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td> 0,5</td>

<td>Irgafos 168</td><td> 0,5</td><td> 0,5</td><td> 0,5</td><td> 0,5</td><td> 0,5</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td> 0,5</td>

<td>Irganox 1010</td><td></td><td></td><td></td><td></td><td></td><td> 0,75</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>Stavinor CA PSE</td><td></td><td></td><td></td><td></td><td></td><td> 0,75</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

EP 2 029 672 B1

<td>MFI (220 ° C, 21.6 kg)</td><td></td><td></td><td></td><td></td><td></td><td> 0,9</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>MFI (230 ° C; 2.16kg)</td><td> 7,3</td><td> 7,3</td><td> 6,1</td><td> 6,8</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td>

<td>ILO (%)</td><td> 37,2</td><td> 41,8</td><td></td><td> 39,1</td><td> 38,4</td><td></td><td> 28,6</td><td> 28,1</td><td> 28,1</td><td> 28,7</td><td> 28,1</td><td> 31,3</td><td> 34,0</td><td> 38,7</td>

<td>UL94 class</td><td>V1</td><td>V0</td><td>V0</td><td>V0</td><td>V0</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td>V0</td>

<td>Creep (temperature)</td><td></td><td>110 ° C</td><td></td><td>110 ° C</td><td>140 ° C</td><td></td><td>&lt;100 ° C</td><td>&lt;100 ° C</td><td>&lt;100 ° C</td><td>&lt;100 ° C</td><td>&lt;100 ° C</td><td>&lt;100 ° C</td><td>&lt;100 ° C</td><td>120 ° C</td>

<td>Elongation at breaking (%)</td><td> 261</td><td> 146</td><td></td><td> 448</td><td> 321</td><td></td><td> 64</td><td> 50</td><td> 45</td><td> 19</td><td> 16</td><td> 45</td><td> 18</td><td> 412</td>

<td>Breaking stress (MPa)</td><td> 8,5</td><td> 7,2</td><td></td><td> 10,7</td><td> 9,8</td><td></td><td> 7,9</td><td> 9,3</td><td> 9,3</td><td> 7,4</td><td> 8,3</td><td> 8,9</td><td> 10</td><td> 7,4</td>

<td>Hardness (Shore D)</td><td></td><td> 42</td><td></td><td> 40</td><td> 42</td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td></td><td> 32</td>

<td>Sweating (O / N)</td><td>N</td><td>N</td><td>N</td><td>N</td><td>N</td><td>N</td><td>N</td><td>N</td><td>N</td><td>N</td><td>N</td><td>N</td><td>N</td><td>ABOUT</td>

EP 2 029 672 B1