Flame-retardant polyamide compounds and their use

Description

[0001] The present invention relates to flame-retardant polyamide compositions and molded parts produced therefrom.

[0002] Flammable plastics generally require flame retardants to meet the high flame retardant requirements demanded by plastics processors and, in some cases, by law. Non-halogenated flame retardant systems, which emit little or no smoke, are preferred—also for ecological reasons.

[0003] Among these flame retardants, the salts of phosphinic acids (phosphinates) have proven particularly effective for thermoplastic polymers (DE 2 252 258 A and DE 2 447 727 A).

[0004] In addition, synergistic combinations of phosphinates with certain nitrogen-containing compounds are known which act more effectively as flame retardants in a whole range of polymers than the phosphinates alone (WO-2002 / 28953 A1 as well as DE 197 34 437 A1 and DE 197 37 727 A1).

[0005] From US 7,420,007 B2 (corresponding to EP 1,544,206 A1) it is known that dialkyl phosphinates containing a small amount of selected telomers are suitable as flame retardants for polymers, whereby the polymer is subject to only a relatively slight degradation when the flame retardant is incorporated into the polymer matrix.

[0006] WO 2012 / 045414 A1 describes flame retardant-stabilizer combinations for thermoplastic polymers. These combinations contain a mixture of a salt of a dialkylphosphinic acid with a salt of phosphonic acid and, optionally, other nitrogen- or phosphorus-nitrogen-containing flame retardants.

[0007] Halogen-free flame retardant mixtures with uniform flow properties are known from DE 10 2014 001 222 A1. These contain salts of dialkylphosphinic acid, non-flammable additives and aluminum phosphite.

[0008] The older priority WO 2018 / 015253 A1 describes flame retardant mixtures containing diorganylphosphinic acid salts and iron.

[0009] Flame retardants often need to be added in high dosages to ensure the plastic meets international standards for flame resistance. Due to their chemical reactivity, which is required for flame retardancy at high temperatures, flame retardants can impair the processing stability of plastics, especially at higher dosages. This can lead to increased polymer degradation, crosslinking reactions, outgassing, or discoloration.

[0010] WO 2014 / 135256 A1 discloses polyamide molding compounds that exhibit significantly improved thermal stability, reduced migration tendency, and good electrical and mechanical properties.

[0011] However, there is currently a lack of flame-retardant phosphinate-containing polyamide compositions that simultaneously achieve all the required properties, such as good electrical values ​​and effective flame retardancy, as well as good demoldability and a smooth surface of the molded part.

[0012] It was therefore an object of the present invention to provide flame-retardant polyamide compositions based on phosphinate-containing flame retardant systems which simultaneously exhibit all of the aforementioned properties and which, in particular, exhibit good electrical values ​​(GWFI, CTI) and effective flame retardancy characterized by the shortest possible after-flame times (UL-94, fire class), as well as good demoldability and a smooth surface of the molded part (surface).

[0013] The invention relates to flame-retardant polyamide compositions containing 25 to 95 wt.% thermoplastic polyamide having a melting point of less than or equal to 290 °C, preferably less than or equal to 280 °C and very particularly preferably less than or equal to 250 °C, determined by differential scanning calorimetry (DSC) at a heating rate of 10 K / second, as component A, 1 to 45 wt.% fillers and / or reinforcing materials, preferably glass fibers, as component B, 1 to 35 wt.% phosphinic acid salt of the formula (I) as component C wherein R 1 and R 2 are ethyl, M is Al, Fe, TiO p or Zn, m is 2 to 3, preferably 2 or 3, and p = (4 - m) / 2 0.01 to 3 wt.% of a compound selected from the group of Al, Fe, TiO p or Zn salts of ethylbutylphosphinic acid, dibutylphosphinic acid, ethylhexylphosphinic acid, butylhexylphosphinic acid and / or dihexylphosphinic acid as component D 0.001 to 1 wt.% of a phosphonic acid salt of the formula (II) as component E wherein R 3 is ethyl, Met is Al, TiO q or Zn, n is 2 to 3, preferably 2 or 3, and q = (4 - n) / 2, 1 to 25 wt.% melamine polyphosphate with an average degree of condensation of 20 to 200 - as component F, 0.05 to 5 wt.% wax selected from the group of polyolefin waxes, amide waxes, natural waxes, long-chain aliphatic carboxylic acids which have chain lengths of C 14 to C 40 and / or their esters or salts as component G, the percentages being based on the total amount of the polyamide composition.

[0014] In the polyamide composition according to the invention, the proportion of component A is 25 to 95 wt.%, preferably 25 to 75 wt.%.

[0015] In the polyamide composition according to the invention, the proportion of component B is 1 to 45 wt.%, preferably 20 to 40 wt.%.

[0016] In the polyamide composition according to the invention, the proportion of component C is 1 to 35 wt.%, preferably 5 to 20 wt.%.

[0017] In the polyamide composition according to the invention, the proportion of component D is 0.01 to 3 wt.%, preferably 0.05 to 1.5 wt.%.

[0018] In the polyamide composition according to the invention, the proportion of component E is 0.001 to 1 wt.%, preferably 0.01 to 0.6 wt.%.

[0019] In the polyamide composition according to the invention, the proportion of component F is 1 to 25 wt.%, preferably 2 to 10 wt.%.

[0020] In the polyamide composition according to the invention, the proportion of component G is 0.05 to 5 wt.%, preferably 0.1 to 2 wt.%.

[0021] The percentages for the proportions of components A to G refer to the total amount of the polyamide composition.

[0022] In the flame-retardant polyamide compositions according to the invention, the proportion of component A 25 to 95 wt.%, the proportion of component B 1 to 45 wt.%, the proportion of component C 1 to 35 wt.%, the proportion of component D 0.01 to 3 wt.%, the proportion of component E 0.001 to 1 wt.%, the proportion of component F 1 to 25 wt.%, and the proportion of component G 0.05 to 5 wt.%, where the percentages refer to the total amount of the polyamide composition.

[0023] Particularly preferred are flame-retardant polyamide compositions in which the proportion of component A 25 to 75 wt.%, the proportion of component B 20 to 40 wt.%, the proportion of component C 5 to 20 wt.%, the proportion of component D 0.05 to 1.5 wt.%, the proportion of component E 0.01 to 0.6 wt.%, the proportion of component F 2 to 10 wt.%, and the proportion of component G 0.1 to 2 wt.% amounts.

[0024] Preferred salts of component C are those in which M m+< Zn 2+< , Fe 3+< or in particular Al 3+<.

[0025] Preferred salts of component D are zinc, iron or, in particular, aluminum salts.

[0026] Preferred salts of component E are those in which Met n+< Zn 2+< or in particular Al 3+<.

[0027] Very particular preference is given to flame-retardant polyamide compositions in which M and Met are Al, m and n are 3 and in which the compounds of component D are present as aluminum salts.

[0028] In a preferred embodiment, the flame-retardant polyamide compositions described above contain inorganic phosphonate as further component H.

[0029] The use of the inorganic phosphonates or phosphorous acid salts (phosphites) used according to the invention as component H as flame retardants is known. WO 2012 / 045414 A1 discloses flame retardant combinations that contain phosphorous acid salts (= phosphites) in addition to phosphinic acid salts.

[0030] The inorganic phosphonate (component H) preferably corresponds to the general formulas (IV) or (V) [(HO)PO 2 ] 2-< p / 2 Kat p+< (IV) [(HO) 2 PO] -< p Kat p+< (V) wherein Kat is a p-valent cation, in particular a cation of an alkali metal, alkaline earth metal, an ammonium cation and / or a cation of Fe, Zn or in particular of Al including the cations Al(OH) or Al(OH) 2 , and p is 1, 2, 3 or 4.

[0031] The inorganic phosphonate (component H) is preferably aluminum phosphite [Al(H2PO3)3], secondary aluminum phosphite [Al2(HPO3)3], basic aluminum phosphite [Al(OH)(H2PO3)2*2aq], aluminum phosphite tetrahydrate [Al2(HPO3)3*4aq], aluminum phosphonate, Al7(HPO3)9(OH)6(1,6-hexanediamine)1.5*12H2O, Al2(HPO3)3<*xAl2O3*nH2O with x = 2.27 - 1 and / or Al4H6P16O18.

[0032] The inorganic phosphonate (component H) is preferably also an aluminum phosphite of the formulas (VI), (VII) and / or (VIII) Al 2 (HPO 3 ) 3 × (H 2 O) q (VI) where q is 0 to 4, Al 2.00 M z (HPO 3 ) y (OH) v × (H 2 O) w (VII) where M is alkali metal cations, z is 0.01 to 1.5 and y is 2.63 to 3.5 and v is 0 to 2 and w is 0 to 4; Al 2.00 (HPO 3 ) u (H 2 PO 3 ) t × (H 2 O) s (VIII), where u is from 2 to 2.99 and from 12 to 0.01 and s is from 0 to 4, and / or aluminum phosphite [Al(H2PO3)3], secondary aluminum phosphite [Al2(HPO3)3], basic aluminum phosphite [Al(OH)(H2PO3)2*2aq], aluminum phosphite tetrahydrate [Al2(HPO3)3*4aq], aluminum phosphonate, Al7(HPO3)9(OH)6(1,6-hexanediamine)1.5*12H2O, Al2(HPO3)3<*xAl2O3*nH2O with x = 2.27-1 and / or Al4H6P16O18.

[0033] Preferred inorganic phosphonates (component H) are salts that are insoluble or sparingly soluble in water.

[0034] Particularly preferred inorganic phosphonates are aluminum, calcium and zinc salts.

[0035] Component H is particularly preferably a reaction product of phosphorous acid and an aluminum compound.

[0036] Particularly preferred components H are aluminum phosphites with the CAS numbers 15099-32-8, 119103-85-4, 220689-59-8, 56287-23-1, 156024-71-4, 71449-76-8 and 15099-32-8.

[0037] The preferred aluminum phosphites are prepared by reacting an aluminum source with a phosphorus source and, optionally, a template in a solvent at 20–200 °C for a period of up to 4 days. The aluminum source and phosphorus source are mixed for 1–4 hours, heated under hydrothermal conditions or at reflux, filtered, washed, and dried, for example, at 110 °C.

[0038] Preferred aluminum sources are aluminum isopropoxide, aluminum nitrate, aluminum chloride, aluminum hydroxide (e.g. pseudoboehmite).

[0039] Preferred phosphorus sources are phosphorous acid, (acidic) ammonium phosphite, alkali phosphites or alkaline earth phosphites.

[0040] Preferred alkali phosphites are disodium phosphite, disodium phosphite hydrate, trisodium phosphite, potassium hydrogen phosphite. Preferred disodium phosphite hydrate is Brüggolen ®< H10 from Brüggemann.

[0041] Preferred templates are 1,6-hexanediamine, guanidine carbonate or ammonia.

[0042] The preferred alkaline earth phosphite is calcium phosphite.

[0043] The preferred ratio of aluminum to phosphorus to solvent is 1:1:3.7 to 1:2.2:100 mol. The ratio of aluminum to template is 1:0 to 1:17 mol. The preferred pH of the reaction solution is 3 to 9. The preferred solvent is water.

[0044] Particularly preferred in the application is the same salt of phosphinic acid as of phosphorous acid, e.g. aluminum diethylphosphinate together with aluminum phosphite or zinc diethylphosphinate together with zinc phosphite.

[0045] In a preferred embodiment, the flame-retardant polyamide compositions described above contain as component H a compound of formula (III) wherein Me is Fe, TiO r , Zn or especially Al, o is 2 to 3, preferably 2 or 3, and r = (4 - o) / 2.

[0046] Preferred compounds of formula III are those in which Me o+< Zn 2+< , Fe 3+< or in particular Al 3+<.

[0047] Component H is preferably present in an amount of 0.005 to 10 wt.%, in particular in an amount of 0.02 to 5 wt.%, based on the total amount of the polyamide composition.

[0048] Preferred flame-retardant polyamide compositions according to the invention are those which have a Comparative Tracking Index, measured according to the International

[0049] Electrotechnical Commission Standard IEC-60112 / 3, greater than or equal to 500 volts.

[0050] Likewise preferred flame-retardant polyamide compositions according to the invention achieve a rating of V0 according to UL-94, in particular measured on molded parts of 3.2 mm to 0.4 mm thickness.

[0051] Further preferred flame-retardant polyamide compositions according to the invention have a Glow Wire Flammability Index according to IEC-60695-2-12 of at least 960 °C, in particular measured on molded parts of 0.75 - 3 mm thickness.

[0052] The polyamide compositions according to the invention contain, as component A, one or more polyamides with a melting point of less than or equal to 290 °C. The melting point is determined by differential scanning calorimetry (DSC) at a heating rate of 10 K / second.

[0053] The polyamides of component A are generally homo- or copolyamides derived from (cyclo)aliphatic dicarboxylic acids or their polyamide-forming derivatives, such as their salts, and from (cyclo)aliphatic diamines or from (cyclo)aliphatic aminocarboxylic acids or their polyamide-forming derivatives, such as their salts.

[0054] The polyamides used according to the invention as component A are thermoplastic polyamides.

[0055] Thermoplastic polyamides are defined, according to Hans Domininghaus in "Die Kunststoffe und ihre Eigenschaften", 5th edition (1998), page 14, as polyamides whose molecular chains have no or more or less long and varying number of side branches, which soften when heated and can be shaped in almost any way.

[0056] The polyamides used according to the invention as component A can be produced by various processes and synthesized from very different building blocks. In specific applications, they can be combined, alone or in combination with processing aids, stabilizers, or polymeric alloying partners, preferably elastomers, to form materials with specifically adjusted combinations of properties. Blends containing proportions of other polymers, preferably polyethylene, polypropylene, or ABS, are also suitable, with one or more compatibilizers optionally being used. The properties of the polyamides can be improved by adding elastomers, e.g., with regard to impact strength, particularly when the polyamides are glass fiber-reinforced, as is the case here. The multitude of possible combinations enables a very large number of products with a wide variety of properties.

[0057] A variety of processes have become known for the production of polyamides, whereby, depending on the desired end product, different monomer building blocks, various chain regulators to adjust a desired molecular weight or even monomers with reactive groups for later post-treatments are used.

[0058] The technically relevant processes for producing polyamides usually involve melt polycondensation. In this context, the hydrolytic polymerization of lactams is also considered a polycondensation.

[0059] Polyamides preferably used as component A are semi-crystalline aliphatic polyamides which can be prepared from aliphatic diamines and aliphatic dicarboxylic acids and / or cycloaliphatic lactams having at least 5 ring members or corresponding amino acids.

[0060] Suitable starting materials include aliphatic dicarboxylic acids, preferably adipic acid, 2,2,4- and 2,4,4-trimethyladipic acid, azelaic acid and / or sebacic acid; aliphatic diamines, preferably tetramethylenediamine, hexamethylenediamine, 1,9-nonanediamine, 2,2,4- and 2,4,4-trimethylhexamethylenediamine; the isomeric diaminodicyclohexylmethanes, diaminodicyclohexylpropanes, bisaminomethylcyclohexane; aminocarboxylic acids, preferably aminocaproic acid; or the corresponding lactams. Copolyamides composed of several of the above-mentioned monomers are included. Particular preference is given to caprolactams, and very particular preference is given to using ε-caprolactam.

[0061] The aliphatic homo- or copolyamides used according to the invention are preferably polyamide 12, polyamide 4, polyamide 4.6, polyamide 6, polyamide 6.6, polyamide 6.9, polyamide 6.10, polyamide 6.12, polyamide 6.66, polyamide 7.7, polyamide 8.8, polyamide 9.9, polyamide 10.9, polyamide 10.10, polyamide 11 or polyamide 12. These are known, for example, under the trade names Nylon ®<, DuPont, Ultramid ®<, BASF, Akulon ®< K122, DSM, Zytel ®< 7301, DuPont; Durethan ®< B 29, Bayer and Grillamid ®<, Ems Chemie.

[0062] Compounds based on PA6, PA6.6 and other aliphatic homo- or copolyamides are also particularly suitable, in which there are 3 to 11 methylene groups per polyamide group in the polymer chain.

[0063] Flame-retardant polyamide compositions in which one or more polyamides are selected from the group consisting of PA 6, PA 6.6, PA 4.6, PA 12, PA 6.10 are used as component A.

[0064] Particularly preferred are flame-retardant polyamide compositions in which polyamide 6.6 or polymer mixtures of polyamide 6.6 and polyamide 6 are used as component A.

[0065] Very particular preference is given to flame-retardant polyamide compositions in which component A consists of at least 75% by weight of polyamide 6.6 and at most 25% by weight of polyamide 6.

[0066] Fillers and / or reinforcing materials, preferably glass fibers, are used as component B. Mixtures of two or more different fillers and / or reinforcing materials can also be used. Preferred fillers are mineral particulate fillers based on talc, mica, silicate, quartz, titanium dioxide, wollastonite, kaolin, amorphous silica, nanoscale minerals, particularly preferably montmorillonite or nano-boehmite, magnesium carbonate, chalk, feldspar, glass spheres, and / or barium sulfate. Mineral particulate fillers based on talc, wollastonite, and / or kaolin are particularly preferred.

[0067] Acicular mineral fillers are also particularly preferably used. According to the invention, acicular mineral fillers are understood to mean mineral fillers with a pronounced acicular character. Acicular wollastonites are preferred. The mineral preferably has a length-to-diameter ratio of 2:1 to 35:1, particularly preferably of 3:1 to 19:1, and especially preferably of 4:1 to 12:1. The average particle size of the acicular mineral fillers used as component B according to the invention is preferably less than 20 µm, particularly preferably less than 15 µm, and especially preferably less than 10 µm, as determined using a CILAS granulometer.

[0068] The components B preferably used according to the invention are reinforcing materials. These can be, for example, reinforcing materials based on carbon fibers and / or glass fibers.

[0069] In a preferred embodiment, the filler and / or reinforcing material can be surface-modified, preferably with an adhesion promoter or adhesion promoter system, particularly preferably silane-based. Particularly when using glass fibers, polymer dispersions, film formers, branching agents, and / or glass fiber processing aids can also be used in addition to silanes.

[0070] The glass fibers preferably used as component B according to the invention can be short glass fibers and / or long glass fibers. Chopped fibers can be used as short or long glass fibers. Short glass fibers can also be used in the form of ground glass fibers. In addition, glass fibers can also be used in the form of continuous fibers, for example in the form of rovings, monofilaments, filament yarns, or twisted yarns, or glass fibers can be used in the form of textile fabrics, for example as glass fabric, glass braid, or glass mat.

[0071] Typical fiber lengths for short glass fibers before incorporation into the polyamide matrix range from 0.05 to 10 mm, preferably from 0.1 to 5 mm. After incorporation into the polyamide matrix, the length of the glass fibers has decreased. Typical fiber lengths for short glass fibers after incorporation into the polyamide matrix range from 0.01 to 2 mm, preferably from 0.02 to 1 mm.

[0072] The diameters of individual fibers can vary widely. Typical diameters of individual fibers range from 5 to 20 µm.

[0073] The glass fibers can have any cross-sectional shape, such as round, elliptical, n-sided, or irregular. Glass fibers with mono- or multilobal cross-sections can be used.

[0074] Glass fibers can be used as continuous fibers or as chopped or milled glass fibers.

[0075] The glass fibers themselves, regardless of their cross-sectional area and length, can be selected, for example, from the group of E-glass fibers, A-glass fibers, C-glass fibers, D-glass fibers, M-glass fibers, S-glass fibers, R-glass fibers, and / or ECR-glass fibers, with E-glass fibers, R-glass fibers, S-glass fibers, and ECR-glass fibers being particularly preferred. The glass fibers are preferably provided with a sizing agent, which preferably contains polyurethane as a film former and aminosilane as an adhesion promoter.

[0076] Particularly preferred E-glass fibers have the following chemical composition: SiO 2 50-56%; Al 2 O 3 12-16%; CaO 16-25%; MgO ≤ 6%; B 2 O 3 6-13%; F ≤ 0.7%; Na 2 O 0.3-2%; K 2 O 0.2-0.5%; Fe 2 O 3 0.3%.

[0077] Particularly preferred R-glass fibers have the following chemical composition: SiO 2 50-65%; Al 2 O 3 20-30%; CaO 6-16%; MgO 5-20%; Na 2 O 0.3-0.5%; K 2 O 0.05-0.2%; Fe 2 O 3 0.2-0.4%, TiO 2 0.1-0.3%.

[0078] Particularly preferred ECR glass fibers have the following chemical composition: SiO 2 57.5-58.5%; Al 2 O 3 17.5-19.0%; CaO 11.5-13.0%; MgO 9.5-11.5.

[0079] The salts of diethylphosphinic acid used according to the invention as component C are known flame retardants for polymeric molding compounds.

[0080] Salts of diethylphosphinic acid with proportions of the phosphinic and phosphonic acid salts used in the invention as components D and E are also known flame retardants. The production of these substance combinations is described, for example, in US Pat. No. 7,420,007 B2.

[0081] The salts of diethylphosphinic acid of component C used according to the invention may contain small amounts of salts of component D and salts of component E, for example up to 10% by weight of component D, preferably 0.01 to 6% by weight, and in particular 0.2 to 2.5% by weight thereof, and up to 10% by weight of component E, preferably 0.01 to 6% by weight, and in particular 0.2 to 2.5% by weight thereof, based on the amount of components C, D and E.

[0082] The salts of ethylphosphonic acid used according to the invention as component E are also known as additives to diethylphosphonates in flame retardants for polymeric molding compositions, for example from WO 2016 / 065971 A1.

[0083] The use of the polyphosphate derivatives of melamine with a degree of condensation greater than or equal to 20, used according to the invention as component F, as flame retardants is also known. DE 10 2005 016 195 A1 discloses a stabilized flame retardant containing 99 to 1 wt.% melamine polyphosphate and 1 to 99 wt.% of an additive with reserve alkalinity. This document also discloses that this flame retardant can be combined with a phosphinic acid and / or a phosphinic acid salt.

[0084] Flame-retardant polyamide compositions according to the invention contain as component F a melamine polyphosphate whose average degree of condensation is from 20 to 200, in particular from 40 to 150.

[0085] In another preferred range, the average degree of condensation is 20 to 100.

[0086] Further preferred flame-retardant polyamide compositions according to the invention contain as component F a melamine polyphosphate which has a decomposition temperature of greater than or equal to 320 °C, in particular greater than or equal to 360 °C and very particularly preferably greater than or equal to 400 °C.

[0087] Melamine polyphosphates known from WO 2006 / 027340 A1 (corresponding to EP 1 789 475 B1) and WO 2000 / 002869 A1 (corresponding to EP 1 095 030 B1) are preferably used as component F.

[0088] Melamine polyphosphates are preferably used whose average degree of condensation is between 20 and 200, in particular between 40 and 150, and whose melamine content is 1.1 to 2.0 mol, in particular 1.2 to 1.8 mol per mole of phosphorus atom.

[0089] Also preferably used are melamine polyphosphates whose average condensation rate (number average) is >20, whose decomposition temperature is greater than 320 °C, whose molar ratio of 1,3,5-triazine compound to phosphorus is less than 1.1, in particular 0.8 to 1.0, and whose pH of a 10% slurry in water at 25 °C is 5 or higher, preferably 5.1 to 6.9.

[0090] In a further preferred embodiment, components C, D, E and F are in particle form, the average particle size (d 50 ) being 1 to 100 µm.

[0091] The waxes added according to the invention as component G are known compounds; they are selected from the group of polyolefin waxes, amide waxes, natural waxes, long-chain aliphatic carboxylic acids (fatty acids) and / or their esters or salts.

[0092] The waxes used according to the invention as component G can be used either as such or in polar-modified form. Polar modification can be achieved, for example, by oxidation with air or with oxygen-containing gases or by grafting, for example, unsaturated carboxylic acids such as maleic acid. Examples of oxidative modification can be found in EP 0 890 583 A1. Examples of modification with unsaturated carboxylic acids can be found in EP 0 941 257 B1.

[0093] Mixtures of different waxes can also be used.

[0094] Examples of polyolefin waxes used according to the invention as component G are those that can be obtained by the polymerization of one or more α-olefins, in particular with metallocene catalysts. Examples of metallocenes and their use for the preparation of polyolefin waxes can be found, for example, in EP 0 571 882 A2.

[0095] Polyolefin waxes preferably used as component G are PE waxes, PTFE waxes, PP waxes, FT paraffins, macro- and microcrystalline paraffins and polar polyolefin waxes.

[0096] Examples of PE waxes are polyethylene homo- and copolymer waxes, which were produced in particular by means of metallocene catalysis and which have a number-average molecular weight of 700 to 10,000 g / mol and a dropping point between 80 and 140 °C.

[0097] Examples of PTFE waxes are polytetrafluoroethylenes with a molecular weight between 30,000 and 2,000,000 g / mol, especially between 100,000 and 1,000,000 g / mol.

[0098] Examples of PP waxes are polypropylene homo- and copolymer waxes, which were produced in particular by means of metallocene catalysis and which have a number-average molecular weight of 700 to 10,000 g / mol and a dropping point between 80 and 160 °C.

[0099] Examples of FT waxes are Fischer-Tropsch paraffins (FT paraffins) with a number-average molecular weight of 400 to 800 g / mol and a dropping point of 80 to 125 °C.

[0100] Examples of macro- and microcrystalline paraffins are paraffins and microcrystalline waxes, which are obtained during petroleum refining. The dropping points of such paraffins are preferably between 45 and 65 °C, while those of microcrystalline waxes are preferably between 73 and 100 °C.

[0101] Examples of polar polyolefin waxes are compounds that can be prepared by oxidizing ethylene or propylene homopolymer and copolymer waxes or by grafting them with maleic anhydride. Particularly preferred are polyolefin waxes with a dropping point between 90 and 165 °C, in particular between 100 and 160 °C, a melt viscosity at 140 °C (polyethylene waxes) or at 170 °C (polypropylene waxes) between 10 and 10,000 mPas, in particular between 50 and 5,000 mPas, and a density at 20 °C between 0.85 and 0.96 g / cm³.

[0102] Particularly preferred waxes for use as component G are amide waxes. These are waxes that can be produced by reacting ammonia or alkylenediamine, such as ethylenediamine or hexamethylenediamine, with saturated and / or unsaturated fatty acids. The fatty acids are long-chain carboxylic acids with preferably 14 to 40 carbon atoms, for example stearic acid, tallow fatty acid, palmitic acid, or erucic acid.

[0103] Other waxes preferred for component G are natural waxes. These include carnauba wax and candelilla wax.

[0104] Other waxes preferably used as component G are long-chain aliphatic carboxylic acids (fatty acids) and / or their esters or salts, wherein the aliphatic carboxylic acids have chain lengths of C 14 to C 40.

[0105] Examples of acid and ester waxes include montan waxes. These contain fatty acids and their esters with a carbon chain length of the carboxylic acid from C22 to C36.

[0106] Preferred ester waxes are reaction products of montan wax acids with mono- or polyhydric alcohols having 2 to 6 C atoms, such as ethanediol, butane-1,3-diol, propane-1,2,3-triol or pentaerythritol.

[0107] Other examples of preferred ester waxes are sorbitan esters. These are reaction products of sorbitol with saturated and / or unsaturated fatty acids and / or montanic acids, for example, stearic acid, tallow fatty acid, palmitic acid, or erucic acid.

[0108] Waxes particularly preferred for use as component G are esters or salts of long-chain aliphatic carboxylic acids (fatty acids) with chain lengths from C 14 to C 40. These esters are reaction products of the aforementioned carboxylic acids with common polyhydric alcohols, such as ethylene glycol, glycerin, trimethylolpropane, or pentaerythritol. Suitable salts of the aforementioned carboxylic acids are primarily alkali metal, alkaline earth metal, aluminum, or zinc salts.

[0109] Component G most preferably comprises esters or salts of stearic acid, such as glycerol monostearate or pentaerythritol tetrastearate or calcium, aluminum or zinc stearate.

[0110] Component G most preferably comprises reaction products of montan wax acids with alkylene glycol, in particular with ethylene glycol.

[0111] Of these, mixtures of ethylene glycol mono-montan wax acid esters, ethylene glycol di-montan wax acid esters, montan wax acids and ethylene glycol are particularly preferred.

[0112] Component G is also particularly preferably a reaction product of montan wax acids with a calcium, aluminum or zinc salt.

[0113] The reaction products are particularly preferably a mixture of 1,3-budanediol mono-montan wax acid ester, 1,3-budanediol di-montan wax acid ester, montan wax acids, 1,3-butanediol, calcium montanate and the calcium salt.

[0114] In a further particularly preferred embodiment, component G comprises alkali metal, alkaline earth metal, aluminum and / or zinc salts of long-chain fatty acids having 14 to 40 C atoms and / or reaction products of long-chain fatty acids having 14 to 40 C atoms with polyhydric alcohols, such as ethylene glycol, glycerol, trimethylolpropane and / or pentaerythritol.

[0115] The polyamide compositions according to the invention may contain further additives as component I. Preferred components I within the meaning of the present invention are antioxidants, UV stabilizers, gamma-ray stabilizers, hydrolysis stabilizers, co-stabilizers for antioxidants, antistatic agents, emulsifiers, nucleating agents, plasticizers, processing aids, impact modifiers, dyes, pigments, and / or other flame retardants that differ from components C, D, E, F, and H.

[0116] These include, in particular, phosphates, such as melamine poly(metal phosphates). Preferred metals for these are the elements of main group 2, main group 3, subgroup 2, subgroup 4, and subgroup VIIIa of the periodic table, as well as cerium and / or lanthanum.

[0117] Melamine poly(metal phosphates) are preferably melamine poly(zinc phosphates), melamine poly(magnesium phosphates) and / or melamine poly(calcium phosphates).

[0118] Preferred are (melamine) 2 Mg(HPO 4 ) 2 , (melamine) 2 Ca(HPO 4 ) 2 , (melamine) 2 Zn(HPO4) 2 , (melamine) 3 Al(HPO 4 ) 3 , (melamine) 2 Mg(P 2 O 7 ), (melamine) 2 Ca(P 2 O 7 ), (melamine) 2 Zn(P 2 O 7 ), (melamine) 3 Al(P 2 O 7 ) 3 / 2 .

[0119] Preferred are melamine poly(metal phosphates) known as hydrogen phosphate or pyrophosphate metalates with complex anions having a four- or six-bonded metal atom as coordination center with bidentate hydrogen phosphate or pyrophosphate ligands.

[0120] Melamine-intercalated aluminum, zinc or magnesium salts of condensed phosphates are also preferred, with bis-melamine zinc diphosphate and / or bis-melamine aluminotriphosphate being very particularly preferred.

[0121] Also preferred are salts of the elements of the 2nd main group, the 3rd main group, the 2nd subgroup, the 4th subgroup and the subgroup VIIIa of the periodic table as well as of cerium and / or lanthanum with anions of the oxoacids of the fifth main group (phosphates, pyrophosphates and polyphosphates).

[0122] Preferred are aluminum phosphates, aluminum monophosphates; aluminum orthophosphates (AlPO 4 ), aluminum hydrogen phosphate (Al 2 (HPO 4 ) 3 ) and / or aluminum dihydrogen phosphate. Also preferred are calcium phosphate, zinc phosphate, titanium phosphate and / or iron phosphate. Preferred are calcium hydrogen phosphate, calcium hydrogen phosphate dihydrate, magnesium hydrogen phosphate, titanium hydrogen phosphate (TIHC) and / or zinc hydrogen phosphate.

[0123] Preferred are aluminum dihydrogen phosphate, magnesium dihydrogen phosphate, calcium dihydrogen phosphate, zinc dihydrogen phosphate, zinc dihydrogen phosphate dihydrate and / or aluminum dihydrogen phosphate.

[0124] Particularly preferred are calcium pyrophosphate, calcium dihydrogen pyrophosphate, magnesium pyrophosphate, zinc pyrophosphate and / or aluminum pyrophosphate.

[0125] The aforementioned and other similar phosphates are offered, for example, by the JM Huber Corporation, USA, under Satire ®< Products. These include the types APP Type II, AMPP, MPP, MPyP, PiPyP, PPaz, Satire ®< 400, Satire ®< 600, EDAP, and others.

[0126] Other phosphates are mentioned, for example, in JP-A-2004204194, DE-A-102007036465 and EP-A-3133112 and are expressly included among the usable components I.

[0127] The other additives are known per se as additives to polyamide compositions and can be used alone or in mixtures or in the form of masterbatches.

[0128] The aforementioned components A, B, C, D, E, F, G, and optionally H and / or I can be processed in a wide variety of combinations to form the flame-retardant polyamide composition according to the invention. It is thus possible to mix the components into the polyamide melt at the beginning or end of the polycondensation or in a subsequent compounding process. Furthermore, there are processing processes in which individual components are added later. This is particularly common when using pigment or additive masterbatches. Furthermore, it is possible to drum-coat components, particularly powdered components, onto the polymer granules, which may be warm from the drying process.

[0129] Two or more of the components of the polyamide compositions according to the invention can also be combined by mixing prior to incorporation into the polyamide matrix. Conventional mixing units can be used, in which the components are mixed in a suitable mixer, e.g., for 0.01 to 10 hours at 0 to 300°C.

[0130] Granules can also be produced from two or more of the components of the polyamide compositions according to the invention, which can then be introduced into the polyamide matrix.

[0131] For this purpose, two or more components of the polyamide composition according to the invention can be processed into granules with granulation aid and / or binder in a suitable mixer or a granulating pan.

[0132] The initially produced raw product can be dried in a suitable dryer or tempered for further grain formation.

[0133] In one embodiment, the polyamide composition according to the invention or two or more components thereof can be produced by roll compaction.

[0134] In one embodiment, the polyamide composition according to the invention or two or more components thereof can be produced by mixing the ingredients, extruding them, chipping them (or optionally breaking and classifying them) and drying them (and optionally coating them).

[0135] In one embodiment, the polyamide composition according to the invention or two or more components thereof can be produced by spray granulation.

[0136] The flame-retardant polymer molding composition of the invention is preferably in granular form, e.g., as an extrudate or as a compound. The granules are preferably cylindrical with a circular, elliptical, or irregular base, spherical, cushion, cubic, cuboid, or prism shape.

[0137] Typical length-to-diameter ratios of the granules are 1 to 50 to 50 to 1, preferably 1 to 5 to 5 to 1.

[0138] The granules preferably have a diameter of 0.5 to 15 mm, particularly preferably 2 to 3 mm and preferably a length of 0.5 to 15 mm, particularly preferably 2 to 5 mm.

[0139] The invention also relates to molded parts produced from the flame-retardant polyamide composition described above comprising components A, B, C, D, E, F and G and optionally components H and / or I.

[0140] The molded parts according to the invention can be any desired shape. Examples include fibers, films, or molded articles obtainable from the flame-retardant polyamide molding compounds according to the invention by any molding process, in particular by injection molding or extrusion.

[0141] The flame-retardant polyamide moldings according to the invention can be produced using any molding process. Examples include injection molding, compression molding, foam injection molding, gas injection molding, blow molding, film casting, calendering, lamination, or coating at elevated temperatures with the flame-retardant polyamide molding compound.

[0142] The molded parts are preferably injection molded parts or extrusion parts.

[0143] The flame-retardant polyamide compositions according to the invention are suitable for the production of fibers, films and molded articles, in particular for applications in the electrical and electronics sectors.

[0144] The invention preferably relates to the use of the flame-retardant polyamide compositions according to the invention in or for plug connectors, current-contacting parts in power distributors (FI protection), circuit boards, potting compounds, power plugs, circuit breakers, lamp housings, LED housings, capacitor housings, coil bodies and fans, protective contacts, plugs, in / on circuit boards, housings for plugs, cables, flexible printed circuit boards, charging cables for mobile phones, engine covers or textile coatings.

[0145] The invention also preferably relates to the use of the flame-retardant polyamide compositions according to the invention for producing molded articles in the form of components for the electrical / electronics sector, in particular for parts of printed circuit boards, housings, films, cables, switches, distributors, relays, resistors, capacitors, coils, lamps, diodes, LEDs, transistors, connectors, regulators, memories and sensors, in the form of large-area components, in particular housing parts for control cabinets and in the form of elaborately designed components with sophisticated geometry.

[0146] The wall thickness of the molded articles according to the invention can typically be up to 10 mm. Molded articles with a wall thickness of less than 1.5 mm are particularly suitable, more preferably less than 1 mm, and particularly preferably less than 0.5 mm.

[0147] The following examples illustrate the invention without limiting it. 1. Components used Commercially available polyamides (component A): Polyamide 6.6 (PA 6.6-GV; melting range of 255-260 °C): Ultramid ®< A27 (BASF) Polyamide 6 (melting range of 217-222 °C): Durethan ®< B29 (Lanxess) Polyamide 6T / 6.6 (melting range of 310-320 °C): Vestamid ®< HAT plus 1000 (Evonik) Glass fibers (component B): Glass fibers PPG HP 3610 10µm diameter, 4.5 mm length (PPG, NL) Flame retardant FM 1 (components C, D and E): Aluminum salt of diethylphosphinic acid containing 0.9 mol% of aluminum ethylbutylphosphinate and 0.5 mol% of aluminum ethylphosphonate produced according to example 3 of the US 7,420,007 B2 Flame retardant FM 2 (components C, D and E): aluminum salt of diethylphosphinic acid containing 2.7 mol% of aluminum ethylbutylphosphinate and 0.8 mol% of aluminum ethylphosphonate prepared according to Example 4 of US 7,420,007 B2 Flame retardant FM 3 (components C, D and E): aluminum salt of diethylphosphinic acid containing 0.5 mol% of aluminum ethylbutylphosphinate and 0.05 mol% of aluminum ethylphosphonate prepared by the process according to US 7,420,007 B2 Flame retardant FM 4 (components C, D and E): aluminum salt of diethylphosphinic acid containing 10 mol% of aluminum ethylbutylphosphinate and 5 mol% of aluminum ethylphosphonate prepared by the process according to US 7,420,007 B2 Flame retardant FM 5 (component C): aluminum salt of diethylphosphinic acid prepared analogously to Example 1 of DE 196 07 635 A1 Flame retardant FM 6 (components C and E): aluminum salt of diethylphosphinic acid containing 8,8 mol% of aluminum ethylphosphonate Flame retardant FM 7 (component H): aluminum salt of phosphonic acid produced according to example 1 of DE 102011120218 A1 Flame retardant FM 8 (component F): melamine polyphosphate produced according to the example of WO 2000 / 002869 A1 Flame retardant FM 9 (not according to the invention): melamine polyphosphate with an average degree of condensation of 18 produced analogously to WO 2000 / 002869 A1 Wax 1 (component G) Licomont ®< CaV 102 (Ca salt of montan wax acid), Clariant Produkte (Deutschland) GmbH Wax 2 (component G): Licowax ®< E (ester of montan wax acid), Clariant Produkte (Deutschland) GmbH 2. Production, processing and testing of flame-retardant polyamide molding compounds,

[0148] The flame retardant components were mixed with the wax in the ratios specified in the tables and incorporated via the side feed of a twin-screw extruder (type Leistritz ZSE 27 / 44D) at temperatures of 260 to 310 °C into PA 6.6, at 250 to 275 °C into PA 6, and at 310 to 330 °C into PA 6T / 6.6. The glass fibers were added via a second side feed. The homogenized polymer strand was drawn off, cooled in a water bath, and then pelletized.

[0149] After sufficient drying, the molding compounds were processed into test specimens on an Arburg 320 C Allrounder injection molding machine at melt temperatures of 250 to 320 °C. They were then tested and classified for flame retardancy using the UL 94 test (Underwriter Laboratories). In addition to the classification, the afterburn time was also specified.

[0150] The Comparative Tracking Index of the molded parts was determined according to the International Electrotechnical Commission Standard IEC-60112 / 3.

[0151] The Glow Wire Flammability Index (GWIT index) was determined according to the standard IEC-60695-2-12.

[0152] The condition of the surface of the molded part was assessed visually.

[0153] Unless otherwise stated, all tests in the respective series were carried out under identical conditions (such as temperature programs, screw geometries and injection molding parameters) for comparability purposes. Examples 1-6, 1a, 1b, 5a and comparative examples V1-V12 with PA 6.6

[0154] The results of the tests with PA 6.6 molding compounds are listed in the examples in the table below. All amounts are given as wt.% and refer to the polyamide molding compound including flame retardants, additives, and reinforcing materials.

[0155] The inventive polyamide compositions of Examples 1 to 6, 1a, 1b, and 5a are molding compounds that achieve UL 94 V-0 flame classification at 0.4 mm, while simultaneously exhibiting CTIs of 600 volts or 550 volts and GWFIs of 960 °C, and possess smooth surfaces. Replacing Wax 2 with Wax 1 resulted in an increase in the CTI value. The resulting molded parts could be demolded without problems. The addition of Component H in Examples 5 and 5a leads to a further improvement in flame retardancy, expressed by a reduced afterburn time.

[0156] Omitting component G in comparative examples C1 to C6 resulted in molded parts with rough surfaces that were also difficult to demold. Flame resistance and GWFI values ​​were consistent with those for the molded parts containing component G. The CTI values ​​were lower compared to the molded parts containing component G.

[0157] The omission of components D and E in Comparative Examples V7 and V8 resulted in a longer afterburn time and a reduced CTI value compared to Examples 1-4. Furthermore, the molded part according to Comparative Example V8 had a rough surface and was difficult to demold.

[0158] The omission of component D in comparative example V9 resulted in a prolonged afterburning time and a reduced CTI value compared to examples 1-4.

[0159] Replacing component F with a component with a lower degree of condensation in comparative example V10 resulted in the polyamide strand foaming during production and no measurements could be taken.

[0160] The omission of component F in comparative example V11 resulted in a deterioration of the fire protection class compared to example 2 and a reduced GWFI value.

[0161] In Comparative Example V12, an improvement in the fire protection class was achieved by increasing the concentration of components C, D, and E compared to Example V11. However, this polyamide composition still exhibited a lower fire protection class and a reduced GWFI value compared to Example 2. Examples 7-12 and comparative examples V12-V26 with PA 6.6 / PA6

[0162] The results of the tests with PA 6 / PA6.6 molding compounds are listed in the examples in the table below. All amounts are given as wt.% and refer to the polyamide molding compound including flame retardants, additives, and reinforcing materials. Table 2: PA 6 / PA 6.6 GF 30 test results (7-12 according to the invention; V11-V20 comparisons; nb = not determined) Example No. 7 V12 8 V13 9 V14 10 V15 11 V16 12 V17 V18 V19 V20 V21 V22 V23 A: Polyamide 6.6 37,8 38 37,8 38 37,8 38 37,8 38 37,8 38 37,8 38 37,8 38 37,8 37,8 42,8 37,8 A: Polyamide 6 15 15 15 15 15 15 15 15 15 15 15 15 15 15 15 15 15 15 B: Glass fibers HP3610 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 C+D+E: FM 1 12 12 - - - - - - - - - - - - - - - - C+D+E: FM 2 - - 12 12 - - - - 10 10 12 12 - - - 12 12 17 C+D+E: FM 3 - - - - 12 12 - - - - - - - - - - - - C+D+E: FM 4 - - - - - - 12 12 - - - - - - - - - - C: FM 5 - - - - - - - - - - - - 12 12 - - - - C+E: FM 6 - - - - - - - - - - - - - - 12 - - - H: FM 7 - - - - - - - - 2 2 - - - - - - - - F: FM 8 5 5 5 5 5 5 5 5 5 5 5 5 5 5 5 - - - Comparison: FM 9 - - - - - - - - - - - - - - - 5 - - G: Wax 1 0,2 - 0,2 - 0,2 - 0,2 - 0,2 - - - 0,2 - 0,2 0,2 0,2 0,2 G: Wax 2 - - - - - - - - - - 0,2 - - - - - - - UL94 0.4mm / time[sec. V-0 / 29 V-0 / 29 V-0 / 23 V-0 / 23 V-0 / 44 V-0 / 44 V-0 / 28 V-0 / 28 V-0 / 14 V-0 / 14 V-0 / 23 V-0 / 23 V-0 / 49 V-0 / 49 V-0 / 47 nb V-2 / 103 V-1 / 89 GWFI [°C] 960 960 960 960 960 960 960 960 960 960 960 960 960 960 960 nb 850 900 CTI [volts] 600 500 600 500 600 500 600 500 600 500 550 500 500 500 500 nb 600 600 surface smooth rough*) smooth rough*) smooth rough*) smooth rough*) smooth rough*) smooth rough*) smooth rough*) smooth nb smooth smooth *)< massive problems when demolding the part from the mold

[0163] The inventive polyamide compositions of Examples 7 to 12 are molding compounds that achieve UL 94 V-0 flame classification at 0.4 mm, while simultaneously exhibiting CTIs of 600 volts or 550 volts and GWFIs of 960 °C, and possess smooth surfaces. Replacing Wax 2 with Wax 1 resulted in an increase in the CTI value. The resulting molded parts could be demolded without problems. The addition of Component H in Example 11 leads to a further improvement in flame retardancy, expressed by a reduced afterburn time.

[0164] Omitting component G in comparative examples V12 to V17 resulted in molded parts with rough surfaces that were also difficult to demold. Flame resistance and GWFI values ​​were consistent with those for the molded parts containing component G. The CTI values ​​were lower compared to the molded parts containing component G.

[0165] The omission of components D and E in Comparative Examples V18 and V19 resulted in a longer afterburn time and a reduced CTI value compared to Examples 7-10. Furthermore, the molded part according to Comparative Example V19 was difficult to demold and had a rough surface.

[0166] The omission of component D in comparative example V20 resulted in a prolonged afterburning time and a reduced CTI value compared to examples 7-10.

[0167] Replacing component F with a component with a lower degree of condensation in comparative example V21 resulted in the polyamide strand foaming during production and no measurements could be taken.

[0168] The omission of component F in comparative example V22 resulted in a deterioration of the fire protection class compared to example 8 and a reduced GWFI value.

[0169] In Comparative Example V23, an improvement in the fire protection class was achieved by increasing the concentration of components C, D, and E compared to Example V22. However, this polyamide composition still exhibited a lower fire protection class and a reduced GWFI value compared to Example 8. Comparison examples V24-V29 with PA 6T / 6.6

[0170] The results of the tests with PA 6T / 6.6 molding compounds are listed in the examples in the table below. All amounts are given as wt.% and refer to the polyamide molding compound including flame retardants, additives, and reinforcing materials. Table 3: PA 6T / 6.6 GF 30 test results (nb = not determined) Example No. V24 V25 V26 V27 V28 V29 A: Polyamide 6T / 6.6 52,8 52,8 52,8 52,8 52,8 52,8 B: Glass fibers HP3610 30 30 30 30 30 30 C+D+E: FM 1 12 - - - - - C+D+E: FM 2 - 12 - - 10 - C+D+E: FM 3 - - 12 - - - C+D+E: FM 4 - - - 12 - - C: FM 5 - - - - - 12 C+E: FM 6 - - - - - - I: FM 7 - - - - 2 - F: FM 8 5 5 5 5 5 5 Comparison: FM 9 - - - - - - G: Wax 1 0,2 0,2 0,2 0,2 0,2 0,2 UL 94 0.4 mm / time [sec.] nb nb nb nb nb nb GWFI [°C] nb nb nb nb nb nb MVR [cm3 / 10 min] nb nb nb nb nb nb Color nb nb nb nb nb nb CTI [volts] nb nb nb nb nb nb

[0171] None of the PA molding compounds from comparative examples V24-V29 could be used to produce test specimens because they proved unprocessable. The polyamide strands foamed during production, and no test specimens suitable for measurements could be produced.

Claims

1. Flame-retardant polyamide composition comprising - 25% to 95% by weight of thermoplastic polyamide having a melting point of not more than 290°C, determined by means of differential scanning calorimetry (DSC) at a heating rate of 10K / second, as component A, - 1% to 45% by weight of fillers and / or reinforcers as component B, - 1% to 35% by weight of phosphinic salt of the formula (I) as component C in which R1 and R2 are ethyl, M is Al, Fe, TiOp or Zn, m is 2 to 3, and p = (4 - m) / 2 - 0.01% to 3% by weight of compound selected from the group of the Al, Fe, TiOp and Zn salts of ethylbutylphosphinic acid, of dibutylphosphinic acid, of ethylhexylphosphinic acid, of butylhexylphosphinic acid and / or of dihexylphosphinic acid as component D - 0.001% to 1% by weight of phosphonic salt of the formula II as component E in which R3 is ethyl, Met is Al, TiOq or Zn, n is 2 to 3, and q = (4 - n) / 2 - 1% to 25% by weight of melamine polyphosphate having an average degree of condensation of 20 to 200 as component F, and - 0.05% to 5% by weight of wax selected from the group of the polyolefin waxes, amide waxes, natural waxes, long-chain aliphatic carboxylic acids having chain length of C14 to C40 and / or the esters or salts thereof as component G, where the percentages are based on the total amount of the polyamide composition.

2. Flame-retardant polyamide composition according to Claim 1, characterized in that M and Met are Al, m and n are 3, and component D is an aluminum salt.

3. Flame-retardant polyamide composition according to Claim 1, characterized in that the proportion of component A is 25% to 75% by weight.

4. Flame-retardant polyamide composition according to Claim 1, characterized in that the proportion of component B is 20% to 40% by weight.

5. Flame-retardant polyamide composition according to Claim 1, characterized in that the proportion of component C is 5% to 20% by weight.

6. Flame-retardant polyamide composition according to Claim 1, characterized in that the proportion of component D is 0.05% to 1.5% by weight.

7. Flame-retardant polyamide composition according to Claim 1, characterized in that the proportion of component E is 0.01% to 0.6% by weight.

8. Flame-retardant polyamide composition according to Claim 1, characterized in that the proportion of component F is 2% to 10% by weight.

9. Flame-retardant polyamide composition according to Claim 1, characterized in that the proportion of component G is 0.1% to 2% by weight.

10. Flame-retardant polyamide composition according to at least one of Claims 1 to 9, characterized in that the polyamide composition comprises inorganic phosphonate of the formula (III) in which Me is Fe, TiOr, Zn or especially Al, o is 2 to 3, preferably 2 or 3 and r = (4 - o) / 2, as further component H, where the compound of the formula (III) is present in an amount of 0.005% to 10% by weight, especially in an amount of 002% to 5% by weight, based on the total amount of the polyamide composition.

11. Flame-retardant polyamide composition according to at least one of Claims 1 to 10, characterized in that it has a comparative tracking index measured by International Electrotechnical Commission Standard IEC-60112 / 3 of not less than 500 volts.

12. Flame-retardant polyamide composition according to at least one of Claims 1 to 11, characterized in that it attains a V-0 assessment according to UL94 from thickness 3.2 mm to 0.4 mm.

13. Flame-retardant polyamide composition according to at least one of Claims 1 to 12, characterized in that it has a glow wire flammability index according to IEC-60695-2-12 of not less than 960°C at thickness 0.75-3 mm.

14. Flame-retardant polyamide composition according to at least one of Claims 1 to 13, characterized in that component A is one or more polyamides selected from the group consisting of PA 6, PA 6,6, PA 4,6, PA 12, PA 6,10.

15. Flame-retardant polyamide composition according to Claim 14, characterized in that component A is nylon-6,6 or comprises polymer mixtures of nylon-6,6 and nylon-6.

16. Flame-retardant polyamide composition according to Claim 15, characterized in that component A consists to an extent of at least 75% by weight of nylon-6,6 and to an extent of at most 25% by weight of nylon-6.

17. Flame-retardant polyamide composition according to at least one of Claims 1 to 16, characterized in that glass fibers are used as component B.

18. Flame-retardant polyamide composition according to at least one of Claims 1 to 17, characterized in that the average degree of condensation of the melamine polyphosphate is 40 to 150.

19. Flame-retardant polyamide composition according to at least one of Claims 1 to 18, characterized in that the melamine polyphosphate has a breakdown temperature of not less than 320°C.

20. Flame-retardant polyamide composition according to at least one of Claims 1 to 19, characterized in that component G is an ester or a salt of long-chain aliphatic carboxylic acids having a chain length of C14 to C40.

21. Flame-retardant polyamide composition according to at least one of Claims 1 to 19, characterized in that component G is a polyamide wax which has been prepared by reacting ammonia or alkylenediamine with saturated and / or unsaturated fatty acids having 14 to 40 carbon atoms.

22. Flame-retardant polyamide composition according to at least one of Claims 1 to 21, characterized in that it comprises further additives as component I, where the further additives are selected from the group consisting of antioxidants, UV stabilizers, gamma ray stabilizers, hydrolysis stabilizers, costabilizers for antioxidants, antistats, emulsifiers, nucleating agents, plasticizers, processing auxiliaries, impact modifiers, dyes, pigments and / or further flame retardants other than components C, D, E and F.

23. Use of the polyamide compositions according to any of Claims 1 to 22 for production of fibers, films and shaped bodies, especially for applications in the electricals and electronics sector.