Flame retardant polyamide composition

Description

[0001] The present invention relates to a flame-retardant polyamide composition and to molded articles containing this flame-retardant polyamide composition.

[0002] Due to their chemical composition, many plastics are highly flammable. To meet the high flame retardancy requirements demanded by plastics processors and, in some cases, by law, plastics must generally be treated with flame retardants. A wide variety of flame retardants and flame retardant synergists are known and commercially available for this purpose. Due to their more favorable fire side effects regarding smoke density and composition, as well as for ecological reasons, non-halogenated flame retardant systems have been preferred for some time.

[0003] Among the non-halogenated flame retardants, the salts of phosphinic acids (phosphinates) have proven to be very effective, particularly for thermoplastic polymers (DE-A-2252258 and DE-A-2447727). Some derivatives of this class of flame retardants are valued and used accordingly due to their low negative influence on the mechanical properties of thermoplastic molding compounds.

[0004] In addition, synergistic combinations of phosphinates with certain nitrogen-containing compounds, in particular with melamine derivatives, have been found to act more effectively as flame retardants in a whole range of polymers than the phosphinates alone (WO-A-2002 / 28953, WO-A-97 / 01664 as well as DE-A-19734437 and DE-A-19737727).

[0005] Furthermore, it has been found that the flame retardancy of various phosphinates in thermoplastic polymers can be significantly improved by adding small amounts of inorganic or mineral compounds that do not contain nitrogen, and that these additives can also improve the flame retardancy of phosphinates in combination with nitrogen-containing synergists (EP-A-0024167, WO-A-2004 / 016684). In particular, the combination of phosphinates with melamine polyphosphate leads to V-0 ratings in polyamides according to the UL 94 test.

[0006] The use of phosphinate-containing flame retardant systems initially resulted in partial polymer degradation, discoloration of the polymer, and smoke development during processing, particularly at processing temperatures above 300 °C. However, these difficulties could be mitigated by the addition of basic or amphoteric oxides, hydroxides, carbonates, silicates, borates, or stannates (WO-A-2004 / 022640).

[0007] To further improve thermal stability, WO 2012 / 045414 discloses the combination of a phosphinic acid salt with a phosphorous acid salt. The flame-retardant effect of the phosphinic acid salts can be significantly improved, particularly in aliphatic polyamides. Compared to the use of melamine polyphosphate as a synergist, no efflorescence is observed after storage in warm, humid conditions. WO-A-2014 / 135256 describes flame-retardant polyamides containing a phosphinic acid salt and a phosphorous acid salt as synergists, along with reinforcing materials and other additives. The resulting polyamide molding compounds exhibit good thermal stability and no tendency to migrate. The flammability rating UL 94 V-0 is achieved, as well as a creep resistance (Comparative Tracking Index, CTI) of 600 volts.

[0008] Halogen-free polyamide compounds often exhibit insufficient glow wire ignition temperature (GWIT) results according to IEC 60335, meaning that the polyamide ignites at the 750 °C glow wire tip. A GWIT of 750 °C or higher is required for the use of flame-retardant polyamide molding compounds in unattended household appliances.

[0009] US-A-2007 / 299171 describes thermoplastics, in particular polyamides, containing a phosphinic acid salt (F1), a reaction product of melamine and phosphoric acid (F2), and a condensation product of melamine (F3), where F1+F2 constitute at least 13%, preferably at least 15%, of the total composition. The simultaneous use of F1, F2, and F3 achieves a GWIT of 775°C. A disadvantage of such formulations is that the use of reaction products of melamine and phosphoric acid can lead to migration effects. Furthermore, thermal stability is limited to approximately 300°C; polymer degradation and decomposition can occur at even higher processing temperatures.

[0010] US 2014 / 0371357 describes thermoplastic polyamides with 10-40 wt.% glass fibers, 10-40 wt.% melam, and 0-15% of a halogen-free flame retardant, where the polyamide contains up to 10 mol.% aromatic monomer units. A GWIT of at least 800 °C is achieved; the halogen-free flame retardant can be a metal phosphinate. A disadvantage of using melam is the high filler content of 30-35% to achieve UL 94 V-0 and GWIT > 750 °C, which reduces the flowability and mechanical properties of the polyamide compounds.

[0011] It was therefore an object of the present invention to provide halogen-free, flame-retardant, thermoplastic polyamide compositions (molding compounds) based on phosphinate-containing flame retardant systems, which have high thermal stability and good mechanical properties, reliably meet both UL 94 V-0 up to 0.4 mm wall thickness of the test specimen and the glow wire requirements Glow Wire Flammability Index (GWFI) 960 °C and GWIT 775 °C for all tested wall thicknesses, show no migration effects and show good flowability and high electrical values ​​(Comparative Tracking Index (CTI) > 550 V).

[0012] It has now been surprisingly found that the glow-wire resistance of phosphinate-containing flame-retardant thermoplastic polyamides can be significantly improved if the molding compound contains, in addition to the phosphinates (component B), a salt of phosphorous acid (also known as phosphonic acid) HP(=O)(OH) 2 (component C)) and a condensation product of melamine (component D). With this special combination, the balanced property profile of the polyamides with regard to electrical and mechanical properties is largely retained. The molding compounds thus obtained surprisingly show no migration of the flame retardants used. In addition, the polyamide composition (molding compound) contains fillers and / or reinforcing materials as component E).

[0013] Thermoplastics are primarily processed in the melt. Hardly any plastic can survive the associated structural and physical changes without undergoing a change in its chemical structure. Crosslinking, oxidation, changes in molecular weight, and thus also changes in physical and technical properties can result. To reduce the stress on the polymers during processing, different additives are used depending on the plastic.

[0014] Often, different additives are used simultaneously, each performing a specific function. Antioxidants and stabilizers are used to ensure that the plastic survives processing without chemical damage and subsequently remains stable against external influences such as heat, UV light, weather, and oxygen (air) for a long time. In addition to improving flow behavior, lubricants prevent the plastic melt from sticking excessively to hot machine parts and act as dispersants for pigments, fillers, and reinforcing materials.

[0015] The use of flame retardants can affect the stability of plastics during melt processing. Flame retardants often need to be added in high dosages to ensure sufficient flame retardancy of the plastic according to international standards. Due to their chemical reactivity, which is necessary for flame retardancy at high temperatures, flame retardants can impair the processing stability of plastics. For example, this can lead to increased polymer degradation, crosslinking reactions, outgassing, or discoloration.

[0016] Polyamides, for example, are stabilized by small amounts of copper halides, aromatic amines, and sterically hindered phenols, with the primary objective of achieving long-term stability at high continuous service temperatures (H. Zweifel (Ed.): "Plastics Additives Handbook", 5th Edition, Carl Hanser Verlag, Munich, 2000, pages 80 to 84).

[0017] The polyamide composition according to the invention can contain as component F) a phosphonite or a phosphite or a phosphonite / phosphite mixture and as component G) an ester or a salt of long-chain aliphatic carboxylic acids (fatty acids) having chain lengths of C 14 to C 40.

[0018] The invention therefore relates to a halogen-free, flame-retardant polyamide composition containing as component A) 15 to 89.9 wt.% of one or more thermoplastic polyamides, as component B) 5 to 20 wt.% of a dialkylphosphinic acid salt of the formula (I) wherein R 1< and R 2< are the same or different and are C 1 -C 18 alkyl, linear, branched or cyclic, MMg, Ca, Al, Sb, Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K and / or a protonated nitrogen base; m1 to 4; n1 to 4; mean, as component C) 2 to 10 wt.% of a salt of phosphorous acid as component D) 2 to 10 wt.% of one or more condensation products of melamine, as component E) 1 to 50 wt.% filler and / or reinforcing material, as component F) 0 to 2 wt.% phosphite of the formula P(OR a< ) 3 , where R a< is the same or different and is C 1 -C 18 alkyl, linear, branched or cyclic, C 6 -C 18 aryl, C 7 -C 18 arylalkyl and / or C 7 -C 18 alkylaryl, or phosphonite or mixtures thereof and as component G) 0.1 to 1 wt.% of an ester or salt of long-chain aliphatic carboxylic acids (fatty acids) which have chain lengths of C 14 to C 40, where the sum of the components is always 100 wt.% and where the thermoplastic polyamides of component A) are the polyamides PA 6T / 66, PA 6T / 6, PA 4T, PA 9T and / or PA 10T.

[0019] The flame-retardant polyamide composition contains 15 to 89.9 wt.% component A), 5 to 20 wt.% component B), 2 to 10 wt.% component C), 2 to 20 wt.% component D), 1 to 50 wt.% component E), 0 to 2 wt.% component F) and 0.1 to 1 wt.% component G).

[0020] Preferably, the flame-retardant polyamide composition contains 15 to 75.8 wt.% component A), 5 to 20 wt.% component B), 2 to 10 wt.% component C), 2 to 10 wt.% component D), 15 to 35 wt.% component E), 0.1 to 1 wt.% component F) and 0.1 to 1 wt.% component G).

[0021] Particularly preferably, the flame-retardant polyamide composition contains 35 to 65.8 wt.% component A), 5 to 20 wt.% component B), 2 to 7 wt.% component C), 2 to 7 wt.% component D), 25 to 35 wt.% component E), 0.1 to 5 wt.% component F) and 0.1 to 5 wt.% component G).

[0022] Preferably, the flame-retardant polyamide composition has a Comparative Tracking Index (CTI) measured according to the International Electrotechnical Commission Standard IEC-60112 / 3 of greater than 550 volts.

[0023] Preferably, the flame-retardant polyamide composition achieves a rating of V-0 according to UL-94 at a sample thickness of 3.2 mm to 0.4 mm.

[0024] Preferably, the flame-retardant polyamide composition has a Glow Wire Flammability Index (GWFI) according to IEC-60695-2-12 of 960 °C with a sample thickness of 0.4 to 3 mm.

[0025] Preferably, the flame-retardant polyamide composition has a Glow Wire Ignition Temperature Index (GWIT) according to IEC-60695-2-13 of 750 °C or more with a sample thickness of 0.4 to 3 mm.

[0026] The polyamide (PA) is selected from the group PA 6T / 66, PA 6T / 6, PA 4T, PA 9T, PA 10T, and combinations thereof.

[0027] Component A) is therefore the polyamides PA 6T / 66, PA 6T / 6, PA 4T, PA 9T and / or PA 10T.

[0028] Component D) is preferably melam, melem and / or melon.

[0029] Component D) is particularly preferably melem.

[0030] Preferably, in component B), R 1< , R 2< are the same or different and are methyl, ethyl, n-propyl, iso-propyl, n-butyl, tert-butyl and / or n-pentyl

[0031] Preferably, the salt of phosphorous acid (component C)) corresponds to the general formula (II) [HP(=O)O 2 ] 2-< M m+< (II) where MMg, Ca, Al, Sb, Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na and / or K.

[0032] The salt of phosphorous acid (component C)) is preferably aluminum phosphite Al(H2PO3)3, secondary aluminum phosphite Al2(HPO3)3, aluminum phosphite tetrahydrate Al2(HPO3)3*4aq, aluminum phosphonate, basic aluminum phosphite Al(OH)(H2PO3)2*2aq, Al7(HPO3)9(OH)6(1,6-hexanediamine)1.5*12H2O, Al2(HPO3)3*xAl2O3*nH2O with x=1-2.27 and n=1-50 and / or Al4H6P16O18.

[0033] Preferably, the salt of phosphorous acid is also an aluminum phosphite of formulas (III), (IV) and / or (V), where formula (III): comprises Al 2 (HPO 3 ) 3 x (H 2 O)q and q0 to 4 means Formula (IV): Al 2.00 M z (HPO 3 ) y (OH) v x (H 2 O) w includes and M represents alkali metal ions, z is 0.01 to 1.5, y is 2.63 to 3.5, v is 0 to 2 and w is 0 to 4; Formula (V): Al 2.00 (HPO 3 ) u (H 2 PO 3 ) t × (H 2 O) s includes and u2 to 2.99 and t2 to 0.01 and s0 to 4 means and / or they are mixtures of aluminum phosphite of the formula (III) with sparingly soluble aluminum salts and nitrogen-free foreign ions, mixtures of aluminum phosphite of the formula (V) with aluminum salts, mixtures of aluminum phosphites of the formulas (III), (IV) and / or (V) with aluminum phosphite [Al(H 2 PO 3 ) 3 ], with secondary aluminum phosphite [Al 2 (HPO 3 ) 3 ], with basic aluminum phosphite [Al(OH)(H 2 PO 3 ) 2 *2aq], with aluminum phosphite tetrahydrate [Al 2 (HPO 3 ) 3 *4aq], with aluminum phosphonate, with Al 7 (HPO 3 ) 9 (OH) 6 (1,6-Hexanediamine) 1.5 *12H 2 O, with Al 2 (HPO 3 ) 3 *xAl 2 O 3 *nH 2 O with x = 1 - 2.27 and n = 1 - 50 and / or with Al 4 HrP 16 O 18 .

[0034] Component C) preferably has an average particle size of 0.2 to 100 µm.

[0035] The reinforcing filler or reinforcing material (component E)) is preferably glass fibers.

[0036] Phosphites of the formula (IX) are preferably used as component F, P(OR a< ) 3 (IX), where R a< has the meaning defined above.

[0037] The phosphonites are preferably those of the general structure R-[P(OR 5< ) 2 ] m (VI) where Purely mono- or polyvalent aliphatic, aromatic or heteroaromatic organic radical and R 5< is a compound of structure (VII) or the two radicals R 5 form a bridging group of structure (VIII) with Adirect bond, O, S, C 1-18 alkylene (linear or branched), C 1-18 alkylidene (linear or branched), in which R 6< independently of one another are C 1-12 alkyl (linear or branched), C 1-12 alkoxy and / or C 5-12 cycloalkyl and n is 0 to 5 and m is 1 to 4.

[0038] Component G) preferably 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.

[0039] The flame-retardant polyamide composition according to the invention according to one or more of claims 1 to 16 may further contain telomers.

[0040] Telomeres in the narrower sense can be formed by the multiple addition of olefins (ethylene, propylene) to the phosphoric acid source (H 3 PO 2 , sodium hypophosphite).

[0041] The telomers are then preferably those of the formula (X) H- (C w H 2w ) k P(O)(OM) (C x H 2x ) l -H (X) where in formula (X), independently of one another, k1 to 9, l1 to 9, w2 to 9, x2 to 9, MMg, Ca, Al, Sb, Sn, Ge, Ti, Fe, Zr, Zn, Ce, Bi, Sr, Mn, Li, Na, K and / or a protonated nitrogen base and the groups (C w H 2w ) k and (C x H 2x ) l can be straight or branched;

[0042] The telomers are preferably metal salts of ethylbutylphosphinic acid, dibutylphosphinic acid, ethylhexylphosphinic acid, butylhexylphosphinic acid, ethyloctylphosphinic acid, sec-butylethylphosphinic acid, 1-ethylbutylbutylphosphinic acid, ethyl-1-methylpentylphosphinic acid, di-sec-butylphosphinic acid (di-1-methylpropylphosphinic acid), propylhexylphosphinic acid, dihexylphosphinic acid, hexylnonylphosphinic acid, propylnonylphosphinic acid, dionylphosphinic acid, dipropylphosphinic acid, butyloctylphosphinic acid, hexyloctylphosphinic acid, dioctylphosphinic acid,

[0043] Telomeres in the broader sense can also be formed by the addition of the phosphoric acid source to organic radicals, which can be formed, for example, from radical initiator and solvent

[0044] Then the telomeres are those of the formula (XI) wherein R 1< , R 2< are the same or different and are C 6 -C 10 -arylene, C 7 -C 20 -alkylarylene, C 7 -C 20 -arylalkylene and / or C 3 -C 16 -cycloalkyl or -bicycloalkyl, MMg, Ca, Al, Sb, Sn, Ge, Ti, Fe, Zr, Zn, Ce, Bi, Sr, Mn, Li, Na, K and / or a protonated nitrogen base.

[0045] Preferably in formula (X) w and x are each 2 to 4 and k and l are each 1 to 4.

[0046] Particularly preferred in formula (X) w and x each represent 2 or 3 and k and l each represent 1 to 3.

[0047] Preferably, in formula (X) and / or (XI), M independently of one another is Al, Ti, Fe or Zn.

[0048] The telomers are preferably metal salts of ethyl(cyclopentylethyl)phosphinic acid, butyl(cyclopentylethyl)phosphinic acid, ethyl(cyclohexylethyl)phosphinic acid, butyl(cyclohexylethyl)phosphinic acid, ethyl(phenylethyl)phosphinic acid, butyl(phenylethyl)phosphinic acid, ethyl(4-methylphenylethyl)phosphinic acid, ethylphenylphosphinic acid, butyl(4-methylphenylethyl)phosphinic acid, butylcyclopentylphosphinic acid, butylcyclohexylethylphosphinic acid, butylphenylphosphinic acid, ethyl(4-methylphenyl)phosphinic acid and / or butyl(4-methylphenyl)phosphinic acid, wherein the metal of the metal salt originates from the group Mg, Ca, Al, Sb, Sn, Ge, Ti, Fe, Zr, Zn, Ce, Bi, Sr, Mn, Li, Na and / or K.

[0049] Telomeres in the broader sense can also be formed by the addition of the phosphoric acid source to organic radicals that arise, for example, during the decomposition of photoinitiators.

[0050] Hydroxymethylethyl-Ethylphosphinsäure, 1-Hydroxy-1-Methylpropyl-Ethylphosphinsäure, Butyl-ethylphosphonsäureester, Acyl-Ethylphosphonsäureanhydrid, Butyl-Ethylphosphonsäure, Butylethylphosphinsäure, Ethylphosphinylisobutyronitril (1-Cyano-1-methylethyl-Ethylphosphinsäure), Propylethylphosphinäsure, t-Butyl-Ethylphosphonsäureester, t-Butyl-Ethylphosphinsäure, Ethylphosphinylessigsäure, Hydroxymethylbutyl-Ethylphosphinsäure, 3-Hydroxy-3-methylpentyl-Ethylphosphinäsure, Propoxyethyl-Ethylphosphinsäure, Phenylethyl-Ethylphosphinsäure, 2-Ethylphosphinylethyl-Laurylsäureester, Ethylpentylphosphinsäure, t-Butoxyethyl-Ethylphosphinsäure, Ethylphosphinylisohexansäurenitril, Hexylethylphosphinsäure, Ethylphosphinylethylsulfat, Ethylphosphinylbuttersäure.

[0051] The invention also relates to a three-dimensional article comprising the flame-retardant polyamide composition according to one or more of claims 1 to 16, characterized in that these are molded bodies, injection-molded parts, extrusion masses and / or extrusion parts.

[0052] The invention further relates to the use of a flame-retardant polyamide composition according to one or more of claims 1 to 16 in or for plug connectors, live 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, textile coatings and other products.

[0053] Surprisingly, it was found that the flame-retardant polyamide compositions of the invention exhibit good flame retardancy (V-0 and GWFI / GWIT) combined with improved flowability, high thermal stability, and high impact strength. Polymer degradation is prevented or significantly reduced, and no mold deposits or efflorescence are observed. Furthermore, the flame-retardant polyamide compositions of the invention exhibit only minimal discoloration during melt processing.

[0054] According to the invention, the compositions contain as component A) at least one thermoplastic polyamide according to claim 1.

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

[0056] The polyamides preferred according to the invention 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 create materials with specifically adjusted combinations of properties. Blends with 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, especially when reinforced polyamides are used. The multitude of possible combinations enables a very large number of products with a wide variety of properties.

[0057] A variety of processes are 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 intended 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] Also particularly suitable are aromatic polyamides derived from m-xylene, diamine, and adipic acid; polyamides prepared from hexamethylenediamine and iso- and / or terephthalic acid and optionally an elastomer as a modifier, e.g., poly-2,4,4-trimethylhexamethyleneterephthalamide or poly-m-phenyleneisophthalamide; block copolymers of the aforementioned polyamides with polyolefins, olefin copolymers, ionomers, or chemically bonded or grafted elastomers, or with polyethers, such as, for example, polyethylene glycol, polypropylene glycol, or polytetramethylene glycol. Furthermore, polyamides or copolyamides modified with EPDM or ABS; and polyamides condensed during processing ("RIM polyamide systems").

[0060] In a preferred embodiment, the compositions according to the invention contain, in addition to the thermoplastic polyamide to be used according to the invention, at least one further thermoplastic polymer, particularly preferably at least one other polyamide.

[0061] PA 6T / 66 and PA 6T / 6 are preferred.

[0062] In a preferred embodiment, conventional additives, in particular mold release agents, stabilizers and / or flow aids, can be mixed into the melt or applied to the surface of the polymers to be used in addition to the thermoplastic polyamide.

[0063] Starting materials for the thermoplastic polyamides of component A) can be synthetically produced, for example, from petrochemical raw materials and / or from renewable raw materials via chemical or biochemical processes.

[0064] Other flame retardants or flame retardant synergists not specifically mentioned here may also be used. In particular, nitrogen-containing flame retardants such as melamine cyanurate, melamine phosphates, and melamine polyphosphates can be added. Other phosphorus flame retardants such as aryl phosphates or red phosphorus can also be used. Furthermore, salts of aliphatic and aromatic sulfonic acids and mineral flame retardant additives such as aluminum and / or magnesium hydroxide, Ca-Mg carbonate hydrates (e.g., DE-A-4236122) can also be used.Also suitable are flame retardant synergists from the group of oxygen-, nitrogen- or sulfur-containing metal compounds, preferably zinc oxide, zinc borate, zinc stannate, zinc hydroxystannate, zinc sulfide, molybdenum oxide, titanium dioxide, magnesium oxide, magnesium carbonate, calcium carbonate, calcium oxide, titanium nitride, boron nitride, magnesium nitride, zinc nitride, zinc phosphate, calcium phosphate, calcium borate, magnesium borate or mixtures thereof.

[0065] Other preferably suitable flame retardant additives are carbon formers, particularly preferably phenol-formaldehyde resins, polycarbonates, polyimides, polysulfones, polyethersulfones or polyether ketones as well as anti-drip agents, in particular tetrafluoroethylene polymers.

[0066] The flame retardants can be added in pure form, as well as via masterbatches or compacts.

[0067] Component B is preferably the aluminum or zinc salt of diethylphosphinic acid.

[0068] Preferably, the aluminum phosphite of formula (III) q0.01 to 0.1.

[0069] Preferably, the aluminum phosphite of formula (IV) z0.15 to 0.4; y2.80 to 3; v0.1 to 0.4 and w0.01 to 0.1.

[0070] Preferably, the aluminum phosphite of formula (V) u2.834 to 2.99; t0.332 to 0.03 and s0.01 to 0.1.

[0071] The condensed melamine compounds are preferably melam or melem.

[0072] As component E), the flame-retardant polyamide compositions according to the invention contain at least one filler or reinforcing material.

[0073] Mixtures of two or more different fillers and / or reinforcing materials, preferably based on talc, mica, silicate, quartz, titanium dioxide, wollastonite, kaolin, amorphous silicas, nanoscale minerals, particularly preferably montmorillonite or nano-boehmite, magnesium carbonate, chalk, feldspar, barium sulfate, glass spheres, and / or fibrous fillers and / or reinforcing materials based on carbon fibers and / or glass fibers, can also be used. Preference is given to using mineral particulate fillers based on talc, mica, silicate, quartz, titanium dioxide, wollastonite, kaolin, amorphous silicas, magnesium carbonate, chalk, feldspar, barium sulfate, and / or glass fibers. Particular preference is given to using mineral particulate fillers based on talc, wollastonite, kaolin, and / or glass fibers, with glass fibers being very particularly preferred.

[0074] Acicular mineral fillers are also particularly preferably used. According to the invention, acicular mineral fillers are understood to be 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 minerals usable 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.

[0075] 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. However, pretreatment is not absolutely necessary. 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.

[0076] The glass fibers most preferably used as component E) according to the invention, which generally have a fiber diameter between 7 and 18 µm, preferably between 9 and 15 µm, are added as continuous fibers or as chopped or milled glass fibers. These fibers can be treated with a suitable sizing system and an adhesion promoter or adhesion promoter system, preferably based on silane.

[0077] The polyamide compositions according to the invention may also contain further additives. Preferred additives for the purposes of the present invention are antioxidants, UV stabilizers, gamma-ray stabilizers, hydrolysis stabilizers, antistatic agents, emulsifiers, nucleating agents, plasticizers, processing aids, impact modifiers, dyes, and pigments. The additives can be used alone or in mixtures or in the form of masterbatches.

[0078] Suitable antioxidants include, for example, alkylated monophenols, e.g. 2,6-di-tert-butyl-4-methylphenol; alkylthiomethylphenols, e.g. 2,4-di-octylthiomethyl-6-tert-butylphenol; hydroquinones and alkylated hydroquinones, e.g. 2,6-di-tert-butyl-4-methoxyphenol; tocopherols, e.g. α-tocopherol, β-tocopherol, γ-tocopherol, δ-tocopherol and mixtures thereof (vitamin E); hydroxylated thiodiphenyl ethers, e.g. B. 2,2'-thio-bis(6-tert-butyl-4-methylphenol), 2,2'-thio-bis(4-octylphenol), 4,4'-thio-bis-(6-tert-butyl-3-methylphenol), 4,4'-thio-bis-(6-tert-butyl-2-methylphenol), 4,4'-thio-bis-(3,6-di-sec-amylphenol), 4,4'-bis-(2,6-di-methyl-4-hydroxyphenyl)-disulfic; Alkylidene bisphenols, e.g. B. 2,2'-methylene-bis-(6-tert-butyl-4-methylphenol; O-, N- and S-benzyl compounds, e.g. 3,5,3',5'-tetra-tert-butyl-4,4'-dihydroxydibenzyl ether; hydroxybenzylated malonates, e.g. dioctadecyl 2,2-bis-(3,5-di-tert-butyl-2-hydrobenzyl)-malonate; hydroxybenzyl aromatics, e.g.1,3,5-Tris-(3,5-di-tert-butyl)-4-hydroxybenzyl)-2,4,6-trimethylbenzo1, 1,4-bis-(3,5-di-tert-butyl-4-hydroxybenzyl)-2,3,5,6-tetramethylbenzot 2,4,6-Tris-(3,5-di-tert-buryl-4-hydroxybenzyl)phenol; Triazine compounds, e.g. B. 2,4-Bis-octylmercapto-6(3,5-di-tert-butyl-4-hydroxyanilino)-1,3,5-triazine; Benzylphosphonates, e.g. B. Dimethyl 2,5-di-tert-butyl-4-hydroxybenzylphosphonate; Acylaminophenols, 4-hydroxylauric acid amide, 4-hydroxystearic acid anilide, N-(3,5-di-tert-butyl-4-hydroxyphenyl)-carbamic acid octyl ester; esters of β-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid with mono- or polyhydric alcohols; esters of β-(5-tert-butyl-4-hydroxy-3-methylphenyl)-propionic acid with mono- or polyhydric alcohols; esters of β-(3,5-dicyclohexyl-4-hydroxyphenyl)-propionic acid with mono- or polyhydric alcohols; esters of 3,5-di-tert-butyl-4-hydroxyphenylacetic acid with mono- or polyhydric alcohols; amides of β-(3,5-di-tert-butyl-4-hydroxyphenyl)-propionic acid, such asN,N'-bis-(3,5-di-tert-butyl4-hydroxyphenylpropionyl)hexamethylenediamine, N,N'-bis-(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)trimethylenediamine, N,N'-bis-(3,5-di-tert-butyl-4-hydroxyphenylpropionyl)hydrazine.

[0079] Particular preference is given to using sterically hindered phenols alone or in combination with phosphites, with the use of N,N'-bis[3-(3',5'-di-tert-butyl-4'-hydroxyphenyl)propionyl]hexamethylenediamine (e.g. Irganox ®< 1098 from BASF SE, Ludwigshafen, Germany) being particularly preferred.

[0080] Suitable UV absorbers and light stabilizers are, for example, 2-(2'-hydroxyphenyl)-benzotriazoles, such as 2-(2'-hydroxy-5'-methylphenyl)-benzotriazole; 2-Hydroxybenzophenones, such as the 4-hydroxy, 4-methoxy, 4-octoxy, 4-decyloxy, 4-dodecyloxy, 4-benzyloxy, 4,2',4-trihydroxy, 2'-hydroxy-4,4'-dimethoxy derivative; esters of optionally substituted benzoic acids, such as B. 4-tert-butylphenyl salicylate, phenyl salicylate, octylphenyl salicylate, dibenzoylresorcinol, bis-(4-tert-butylbenzoyl)-resorcinol, benzoylresorcinol, 2,4-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate, hexadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, octadecyl 3,5-di-tert-butyl-4-hydroxybenzoate, 2-methyl-4,6-di-tert-butylphenyl 3,5-di-tert-butyl-4-hydroxybenzoate; acrylates, such as. B. α-cyano-β,β-diphenylacrylic acid ethyl ester or isooctyl ester, α-carbomethoxycinnamic acid methyl ester, α-cyano-β-methyl-p-methoxycinnamic acid methyl ester or butyl ester, α-carbomethoxy-p-methoxycinnamic acid methyl ester, N-(β-carbomethoxy-β-cyanovinyl)-2-methyl-indoline.

[0081] Preferred colorants are inorganic pigments, in particular titanium dioxide, ultramarine blue, iron oxide, zinc sulfide or carbon black, as well as organic pigments, preferably phthalocyanines, quinacridones, perylenes and dyes, preferably nigrosine and anthraquinones.

[0082] Suitable polyamide stabilizers include copper salts in combination with iodides and / or phosphorus compounds and salts of divalent manganese.

[0083] Suitable basic co-stabilizers are melamine, polyvinylpyrrolidone, dicyandiamide, triallyl cyanurate, urea derivatives, hydrazine derivatives, amines, polyamides, polyurethanes, alkali and alkaline earth salts of higher fatty acids, for example Ca stearate, Zn stearate, Mg behenate, Mg stearate, Na ricinoleate, K palmitate, antimony catecholate or tin catecholate.

[0084] Suitable nucleating agents include, for example, 4-tert-butylbenzoic acid, adipic acid and diphenylacetic acid, aluminum oxide or silicon dioxide and, most preferably, talc, although this list is not exhaustive.

[0085] Preferred flow aids are copolymers of at least one α-olefin with at least one methacrylic acid ester or acrylic acid ester of an aliphatic alcohol. Particular preference is given to copolymers in which the α-olefin is composed of ethene and / or propene, and the methacrylic acid ester or acrylic acid ester contains linear or branched alkyl groups having 6 to 20 carbon atoms as the alcohol component. 2-ethylhexyl acrylate is very particularly preferred.

[0086] Copolymers suitable as flow aids according to the invention are characterized not only by their composition but also by their low molecular weight. Accordingly, copolymers that have a melt flow index (MFI) value, measured at 190°C and a load of 2.16 kg, of at least 100 g / 10 min, preferably of at least 150 g / 10 min, particularly preferably of at least 300 g / 10 min, are particularly suitable for the compositions to be protected from thermal degradation according to the invention. The MFI is used to characterize the flow of a thermoplastic melt and is subject to the standards ISO 1133 or ASTM D 1238. The MFI and all data on the MFI in the context of the present invention refer to or were uniformly measured or determined according to ISO 1133 at 190°C and a test weight of 2.16 kg.

[0087] Preferred plasticizers are dioctyl phthalate, dibenzyl phthalate, butylbenzyl phthalate, hydrocarbon oils or N-(n-butyl)benzenesulfonamide.

[0088] However, the present invention also relates to products, preferably fibers, films or molded articles, obtainable from the compositions described according to the invention by injection molding or extrusion.

[0089] Suitable phosphinates (component B) are described in PCT / WO97 / 39053. Particularly preferred phosphinates are aluminum, calcium, and zinc phosphinates.

[0090] Preferred salts of phosphorous acid (component C)) are salts that are insoluble or sparingly soluble in water.

[0091] Particularly preferred salts of phosphorous acid are the aluminum, calcium and zinc salts.

[0092] Component C) is particularly preferably a reaction product of phosphorous acid and an aluminum compound.

[0093] Preferred are aluminum phosphites with CAS numbers 15099-32-8, 119103-85-4, 220689-59-8, 56287-23-1, 156024-71-4, 71449-76-8 and 15099-32-8.

[0094] The aluminum phosphites preferably have particle sizes of 0.2 - 100 µm.

[0095] 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.

[0096] Preferred aluminum sources are aluminum isopropoxide, aluminum nitrate, aluminum chloride and aluminum hydroxide (e.g. pseudoboehmite).

[0097] Preferred phosphorus sources are phosphorous acid, (acidic) ammonium phosphite, alkali phosphites or alkaline earth phosphites.

[0098] Preferred alkali phosphites are disodium phosphite, disodium phosphite hydrate, trisodium phosphite and potassium hydrogen phosphite.

[0099] The preferred disodium phosphite hydrate is Brüggolen ®< H10 from Brüggemann.

[0100] Preferred templates are 1,6-hexanediamine, guanidine carbonate or ammonia.

[0101] The preferred alkaline earth phosphite is calcium phosphite.

[0102] 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.

[0103] Particularly preferred in the application is the same salt of phosphinic acid as of phosphorous acid, e.g. aluminum dialkylphosphinate together with aluminum phosphite or zinc dialkylphosphinate together with zinc phosphite.

[0104] Component G) preferably comprises alkali metal, alkaline earth metal, aluminum, and / or zinc salts of long-chain fatty acids having 14 to 40 carbon atoms and / or reaction products of long-chain fatty acids having 14 to 40 carbon atoms with polyhydric alcohols, such as ethylene glycol, glycerol, trimethylolpropane, and / or pentaerythritol. It is particularly preferably aluminum, calcium, or zinc stearate or calcium montanate.

[0105] Other flame retardants that are preferred are aryl phosphates, phosphonates, salts of hypophosphorous acid and red phosphorus.

[0106] Phosphites of the formula (IX) are preferably used as component F, P(OR a< ) 3 (IX) where R a< has the meanings given above.

[0107] Preferred phosphonites are the residues R 4 -C 18 alkyl (linear or branched), C 4 -C 18 alkylene (linear or branched), C 5 -C 12 cycloalkyl, C 5 -C 12 cycloalkylene, C 6 -C 24 aryl or heteroaryl, C 6 -C 24 arylene or heteroarylene, which may also be further substituted; R 6< independently of one another denotes C 1 -C 8 alkyl (linear or branched), C 1 -C 8 alkoxy, cyclohexyl; A direct bond, O, C 1 -C 8 alkylene (linear or branched), C 1 -C 8 alkylidene (linear or branched) and n 0 to 3, m 1 to 3.

[0108] Particularly preferred among the phosphonites are the residues RCyclohexyl, phenyl, phenylene, biphenyl and biphenylene R 6< independently of one another are C 1 - C 8 alkyl (linear or branched), C 1 -C 8 alkoxy, cyclohexyl Adirect bond, O, C 1 - C 6 alkylidene (linear or branched) and n1 to 3 m1 or 2.

[0109] Furthermore, mixtures of compounds according to the above claims in combination with phosphites are claimed. Particular preference is given to compounds which, based on the above definitions, are prepared by a Friedel-Crafts reaction of an aromatic or heteroaromatic compound, such as benzene, biphenyl or diphenyl ether, with phosphorus trihalides, preferably phosphorus trichloride, in the presence of a Friedel-Crafts catalyst such as aluminum chloride, zinc chloride, or iron chloride, followed by reaction with the phenols underlying structures (IX) and (VI). This expressly includes mixtures with phosphites which are formed from excess phosphorus trihalide and the phenols described above according to the reaction sequence mentioned.

[0110] From this group of compounds, the following structures (XII) and (XIII) are preferred: where n can be 0 or 1 and these mixtures can optionally also contain portions of the compound (XIV) or (XV):

[0111] Suitable as component G) are esters or salts of long-chain aliphatic carboxylic acids (fatty acids) with chain lengths from C 14 to C 40. The 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 or alkaline earth metal salts, or aluminum and zinc salts.

[0112] Component G) is preferably an ester or salt of stearic acid such as glycerol monostearate or calcium stearate.

[0113] Component G) is preferably also a reaction product of montan wax acids with ethylene glycol.

[0114] The reaction products are preferably a mixture of ethylene glycol mono-montan wax acid ester, ethylene glycol dimontan wax acid ester, montan wax acids and ethylene glycol.

[0115] Component G) is preferably also a reaction product of montan wax acids with a calcium salt.

[0116] 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.

[0117] The compositions according to the invention according to one or more of claims 1 to 16 preferably have a Glow Wire Ignition Temperature (GWIT) according to IEC-60695-2-13 of 775 °C or more with a thickness of the sample bodies of 0.4 - 3 mm.

[0118] The aforementioned additives can be incorporated into the plastic in a wide variety of process steps. For example, with polyamides, it is possible to mix the additives into the polymer melt at the beginning or end of the polymerization / polycondensation process, or in a subsequent compounding process. There are also processing processes in which the additives are added later. This is particularly common when using pigment or additive masterbatches. It is also possible to drum-coat additives, especially powdered additives, onto the polymer granules, which may be warm from the drying process.

[0119] Finally, the invention also relates to a process for producing flame-retardant polymer moldings, characterized in that flame-retardant polymer molding compositions according to the invention are processed into the flame-retardant polymer molding by injection molding (e.g. injection molding machine type Aarburg Allrounder) and pressing, foam injection molding, gas injection molding, blow molding, film casting, calendering, lamination or coating at elevated temperatures. Examples

[0120] 1. Components used Commercially available polyamides (component A)): Polyamide 6.6 (PA 6.6-GV): Ultramid ®< A27 (BASF SE, Germany) Polyamide 6: Ultramid ®< B27 (BASF SE, Germany) Polyamide 6T / 66: Vestamid HTplus M1000 (Evonik, Germany) Polyamide 10T: Vestamid HTplus M3000 (Evonik, Germany) Component E): PPG HP 3610 glass fibers with a diameter of 10 µm and a length of 4.5 mm (PPG, Netherlands) Flame retardant (component B)): Aluminum salt of diethylphosphinic acid, hereinafter referred to as DEPAL Flame retardant (component C)): Aluminum salt of phosphorous acid, hereinafter referred to as PHOPAL Flame retardant (component D)): Delacal 360 (Melam) Delacal 420 (Melem) Delacal 500 (Melon), all from Delamin Ltd, UK Comparison: MPP, melamine polyphosphate, Melapur ®< 200 / 70, BASF AG, D Phosphonites (component F)): Sandostab ®< P-EPQ, Clariant GmbH, D Wax components (component G)): Licowax ®< E, Clariant Produkte (Deutschland) GmbH, D (esters of montan wax acid) 2.Production, processing and testing of flame-retardant polyamide molding compounds.

[0121] The flame retardant components were mixed with the phosphonite, lubricants, and stabilizers in the ratios specified in the table and incorporated into PA 6.6 via the side feed of a twin-screw extruder (Leistritz ZSE 27 / 44D) at temperatures of 260 to 310 °C, or into PA 6 at 250 to 275 °C. 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.

[0122] After sufficient drying, the molding compounds were processed into test specimens on an injection molding machine (type Arburg 320 C Allrounder) at melt temperatures of 250 to 300 °C and tested and classified for flame retardancy using the UL 94 test (Underwriter Laboratories).

[0123] According to UL 94, the following fire classes apply: V-0: no afterburning lasting longer than 10 seconds, the sum of the afterburning times for 10 flame applications does not exceed 50 seconds, no burning droplets, no complete burning of the sample, no afterglow of the sample lasting longer than 30 seconds after the end of the flame application. V-1: no afterburning lasting longer than 30 seconds after the end of the flame application, the sum of the afterburning times for 10 flame applications does not exceed 250 seconds, no afterglow of the sample lasting longer than 60 seconds after the end of the flame application, other criteria as for V-0. V-2: Ignition of the cotton wool due to burning droplets, other criteria as for V-1.

[0124] Not classifiable (nkl): does not meet fire class V-2.

[0125] Glow-wire resistance was determined using the glow-wire flammability index (GWFI) test according to IEC 60695-2-12 and the glow-wire ignition temperature (GWIT) test according to IEC 60695-2-13. In the GWFI test, three test specimens (e.g., plates measuring 60 x 60 x 1.5 mm) are tested using a glowing wire at temperatures between 550 and 960 °C to determine the maximum temperature at which an afterburning time of 30 seconds is not exceeded and the specimen does not drip off while burning. In the GWIT test, a comparable measurement procedure specifies the glow-wire ignition temperature, which is 25°C (30°C between 900°C and 960°C) higher than the maximum glow-wire temperature that does not lead to ignition in three consecutive tests, even during the glow-wire exposure time. Ignition is defined as a flame with a burning time of 5 seconds or more.

[0126] The flowability of the molding compounds was determined by determining the melt volume index (MVR) at 275 °C / 2.16 kg. Higher MVR values ​​indicate better flowability during the injection molding process. However, a sharp increase in the MVR value can also indicate polymer degradation.

[0127] Unless otherwise stated, all tests in the respective series were carried out under identical conditions (temperature programs, screw geometries, injection molding parameters, etc.) for comparability purposes.

[0128] The results in which the flame retardant-stabilizer mixture was used in non-inventive compositions are listed in Examples B1-B3. All amounts are given as wt. % and refer to the plastic molding compound including the flame retardants, additives, and reinforcing materials. Table 1: PA 66 GF 30 test results. V1-V4 are comparative examples, B1 to B3 are non-inventive polyamide molding compounds. V1 V2 V3 V4 B1 B2 B3 A: Polyamide 66 [Wt.%] 49,55 49,55 49,55 39,55 39,55 49,30 49,30 A: Polyamide 6 [Wt.%] 10 10 E: Glass fibers HP3610 [Wt.%] 30 30 30 30 30 30 30 B: DEPAL [Wt.%] 20 17 15 10 14 12 12 C: PHOPAL [Wt.%] 3 3 3 3 MPP [Wt.%] 10 D1: Delacal 360 [Wt.%] 5 3 5 D2: Delacal 420 [Wt.%] 5 G: Licowax E [Wt.%] 0,25 0,25 0,25 0,25 0,25 0,25 0,25 F: P-EPQ [Wt.%] 0,20 0,20 0,20 0,20 0,20 0,20 0,20 Measurement results UL 94 at 0.4 mm thickness V-1 V-0 V-1 V-0 V-0 V-0 V-0 GWFI at 0.4 mm thickness [°C] 850 960 850 960 960 960 960 MVR 275 °C / 2.16 kg 4 5 6 17 9 8 10 GWIT at 0.75 mm thickness [°C] 700 725 725 775 800 800 775 Color of the test specimens** Yellow Yellow White White White White White Efflorescence* no no no clearly no no no CTI [Volt] 600 600 550 550 600 600 600 Impact strength [kJ / m 2 ] 60 63 58 61 68 71 69 Notched impact strength [kJ / m 2 ] 12 11 11 10 14 14 12 * 14 days 100% humidity 70 °C ** yellow: yellowness index > 20

[0129] Only by combining polyamide, glass fibers, DEPAL, PHOPAL, and melam or melem can polyamide molding compounds be obtained that meet UL 94 V-0 fire classification at 0.4 mm and simultaneously exhibit a GWIT greater than 775°C and a CTI of 600 volts, impact strength greater than 65 kJ / m², notched impact strength greater than 10 kJ / m², and exhibit no discoloration (yellowness index < 20) or efflorescence. Furthermore, only these compositions exhibit the desired degree of whiteness. Using DEPAL without PHOPAL (V1) does not achieve V-0, while combining DEPAL with MPP (V4) achieves V-0 and a GWIT of 775°C, but the polyamide molding compound exhibits discoloration and efflorescence. A CTI of 600V is also not achieved. The combination of DEPAL with PHOPAL does not reach the GWIT > =775 °C, the combination of DEPAL with Melam (V3) does not meet UL 94 V-0 and GWIT 775 °C. Table 2: PA 6 GF 30 test results. V5-V7 are comparative examples, B4 and B5 are non-inventive polyamide molding compounds. V5 V6 V7 B4 B5 A: Polyamide 6 [Wt.%] 49,55 49,55 49,55 49,55 49,55 E: Glass fibers HP3610 [Wt.%] 30 30 30 30 30 B: DEPAL [Wt.%] 20 12 17 12 14 C: PHOPAL [Wt.%] 3 3 3 MPP [Wt.%] 8 D2: Delacal 420 [Wt.%] 5 3 G: Licowax E [Wt.%] 0,25 0,25 0,25 0,25 0,25 F: P-EPQ [Wt.%] 0,20 0,20 0,20 0,20 0,20 Measurement results UL 94 at 0.4 mm thickness V-1 V-0 V-0 V-0 V-0 GWIT at 0.75 mm thickness [°C] 700 775 725 800 775 MVR 250°C / 2.16 kg 5 12 5 10 9 Efflorescence* no clearly no no no CTI [Volt] 600 550 600 600 600 Impact strength [kJ / m 2 ] 61 59 62 67 65 Notched impact strength [kJ / m 2 ] 11 9,8 10 12 12 * 14 days 100% humidity 70 °C

[0130] The tests in polyamide 6 show a similar picture: only the combination of polyamide 6 with glass fibers, DEPAL, PHOPAL and Melem produces molding compounds that simultaneously exhibit UL 94 V-0 at 0.4 mm, GWIT >= 775 °C, CTI 600V, no efflorescence, good flowability and good mechanical properties. Table 3: PA 10T GF 30 test results. V8-V10 are comparative examples, B6 and B7 are polyamide molding compounds according to the invention. V8 V9 V10 B6 B7 A: Polyamide 10T [Wt.%] 49,55 49,55 49,55 49,55 49,55 E: Glass fibers HP3610 [Wt.%] 30 30 30 30 30 B: DEPAL [Wt.%] 20 12 17 12 14 C: PHOPAL [Wt.%] 3 3 3 D2: Delacal 420 [Wt.%] 8 5 3 G: Licowax E [Wt.%] 0,25 0,25 0,25 0,25 0,25 F: P-EPQ [Wt.%] 0,20 0,20 0,20 0,20 0,20 Measurement results UL 94 at 0.4 mm thickness V-1 V-1 V-0 V-0 V-0 GWIT at 0.75 mm thickness [°C] 750 750 750 800 825 Efflorescence* no clearly no no no CTI [Volt] 600 550 600 600 600 Impact strength [kJ / m 2 ] 70 61 61 71 68 Notched impact strength [kJ / m 2 ] 9 8 9 8 9 * 14 days 100% humidity 70 °C

[0131] Even in polyamide 10T, only the inventive combination of polyamide with glass fibers, DEPAL, PHOPAL, and Melem produces molding compounds that simultaneously meet UL 94 V-0 at 0.4 mm, GWIT >= 775 °C, CTI 600V, no efflorescence, and good mechanical properties. The combination of DEPAL and MPP cannot be processed in PA 10T. Table 4: PA 6T / 66 GF 30 test results. V11-V13 are comparative examples, B8 and B9 are polyamide molding compounds according to the invention. V11 V12 V13 B8 B9 A: Polyamide 6T / 66 [Wt.%] 54,55 54,55 54,55 54,55 54,55 E: Glass fibers HP3610 [Wt.%] 30 30 30 30 30 B: DEPAL [Wt.%] 15 10 12 10 8 C: PHOPAL [Wt.%] 3 2 2 D2: Delacal 500 [Wt.%] 5 3 5 G: Licowax E [Wt.%] 0,25 0,25 0,25 0,25 0,25 F: P-EPQ [Wt.%] 0,20 0,20 0,20 0,20 0,20 Measurement results UL 94 at 0.4 mm thickness V-0 V-1 V-0 V-0 V-0 GWIT at 0.75 mm thickness [°C] 750 750 750 825 800 Efflorescence* no no no no no CTI [Volt] 600 600 600 600 600 Impact strength [kJ / m 2 ] 62 58 61 63 62 Notched impact strength [kJ / m 2 ] 7 7 8 8 7 * 14 days 100% humidity 70 °C

[0132] In polyamide 6T / 66, the inventive combination of polyamide with glass fibers, DEPAL, PHOPAL, and Melon produces molding compounds that simultaneously meet UL 94 V-0 at 0.4 mm, GWIT >= 775 °C, CTI 600V, no efflorescence, and good mechanical properties. The combination of DEPAL and MPP cannot be processed in PA 6T / 66 either.

[0133] Overall, only the combinations according to the invention achieve all the required parameters.

Claims

1. Halogen-free, flame-retardant polyamide composition comprising as component A) 15% to 89.9% by weight of one or more thermoplastic polyamides, as component B) 5% to 20% by weight of a dialkylphosphinic salt of the formula (I) in which R1 and R2 are the same or different and are C1-C18-alkyl in linear, branched or cyclic form, M is Mg, Ca, Al, Sb, Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, K and / or a protonated nitrogen base; m is 1 to 4; n is 1 to 4; as component C) 2% to 10% by weight of a salt of phosphorous acid, as component D) 2% to 10% by weight of one or more condensation products of melamine, as component E) 1% to 50% by weight of filler and / or reinforcer, as component F) 0% to 2% by weight of phosphite of the formula P(ORa)3 where Ra is the same or different and is C1-C18-alkyl in linear, branched or cyclic form, C6-C18-aryl, C7-C18-arylalkyl and / or C7-C18-alkylaryl, or phosphonite or mixtures thereof, and as component G) 0.1% to 1% by weight of an ester or salt of long-chain aliphatic carboxylic acids (fatty acids) which have chain lengths of C14 to C40, where the sum total of the components is always 100% by weight and where the thermoplastic polyamides of component A) are polyamides PA 6T / 66, PA 6T / 6, PA 4T, PA 9T and / or PA 10T.

2. Flame-retardant polyamide composition according to Claim 1, comprising 15% to 75.8%by weight of component A),5% to 20%by weight of component B),2% to 10%by weight of component C),2% to 10%by weight of component D),15% to 35%by weight of component E),0.1% to 1%by weight of component F) and0.1% to 1%by weight of component G).

3. Flame-retardant polyamide composition according to one or more of Claims 1 to 2, comprising 35% to 65.8%by weight of component A),5% to 20%by weight of component B),2% to 7%by weight of component C),2% to 7%by weight of component D),25% to 35%by weight of component E),0.1% to 0.5%by weight of component F) and0.1% to 0.5%by weight of component G).

4. Flame-retardant polyamide composition according to one or more of Claims 1 to 3, characterized in that it has a comparative tracking index (CTI) of greater than 500 volts, measured according to International Electrotechnical Commission Standard IEC 60112 / 3.

5. Flame-retardant polyamide composition according to one or more of Claims 1 to 5, characterized in that it attains a V-0 assessment according to UL-94 at a specimen thickness of 3.2 mm to 0.4 mm.

6. Flame-retardant polyamide composition according to one or more of Claims 1 to 5, characterized in that it has a glow wire flammability index (GWFI) according to IEC 60695-2-12 of 850°C or more at a specimen thickness of 0.4 to 3 mm.

7. Flame-retardant polyamide composition according to one or more of Claims 1 to 5, characterized in that it has a glow wire ignition temperature index (GWIT) according to IEC 60695-2-13 of 750°C or more at a specimen thickness of 0.4 to 3 mm.

8. Flame-retardant polyamide composition according to one or more of Claims 1 to 7, characterized in that component D) is melam, melem and / or melon.

9. Flame-retardant polyamide composition according to one or more of Claims 1 to 8, characterized in that component D) is melem.

10. Flame-retardant polyamide composition according to one or more of Claims 1 to 9, characterized in that, in component B), R1 and R2 are the same or different and are methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl and / or n-pentyl.

11. Flame-retardant polyamide composition according to one or more of Claims 1 to 10, characterized in that the salt of phosphorous acid (component C)) conforms to the formula (II)         [HP(=O)O2]2- M m+     (II) in which M is Mg, Ca, Al, Sb, Sn, Ge, Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na and / or K.

12. Flame-retardant polyamide composition according to one or more of Claims 1 to 10, characterized in that the salt of phosphorous acid (component C)) is aluminum phosphite Al(H2PO3)3, secondary aluminum phosphite Al2(HPO3)3, aluminum phosphite tetrahydrate Al2(HPO3)3*4aq, aluminum phosphonate, basic aluminum phosphite Al(OH)(H2PO3)2*2aq, Al7(HPO3)9(OH)6(1,6-hexanediamine)1.5*12H2O, Al2(HPO3)3*xAl2O3*nH2O with x = 1-2.27 and n = 1-50 and / or Al4H6P16O18.

13. Flame-retardant polyamide composition according to one or more of Claims 1 to 10, characterized in that the salt of phosphorous acid comprises aluminum phosphites of the formulae (III), (IV) and / or (V), where         Formula (III):     Al2(HPO3)3 x (H2O)q and q is 0 to 4;         Formula (IV)     Al2.00Mz(HPO3)y(OH)v x (H20)w and M represents alkali metal ions, z is 0.01 to 1.5, y is 2.63 to 3.5, v is 0 to 2 and w is 0 to 4;         Formula (V)     Al2.00(HPO3)u(H2PO3)t x (H2O)s and u is 2 to 2.99 and t is 2 to 0.01 and s is 0 to 4, and / or comprises mixtures of aluminum phosphite of the formula (VII) with sparingly soluble aluminum salts and nitrogen-free extraneous ions, mixtures of aluminum phosphite of the formula (IX) with aluminum salts, mixtures of aluminum phosphite of the formulae (VII) to (IX) with aluminum phosphite [Al(H2PO3)3], with secondary aluminum phosphite [Al2(HPO3)3], with basic aluminum phosphite [Al(OH)(H2PO3)2*2aq], with aluminum phosphite tetrahydrate [Al2(HPO3)3*4aq], with aluminum phosphonate, with Al7(HPO3)9(OH)6(1,6-hexanediamine)1.5*12H2O, with Al2(HPO3)3*xAl2O3*nH2O with x = 1-2.27 and n = 1-50 and / or with Al4H6P16O18.

14. Flame-retardant polyamide composition according to one or more of Claims 1 to 13, characterized in that the reinforcing filler or reinforcer (component E)) comprises glass fibers.

15. Flame-retardant polyamide composition according to one or more of Claims 1 to 14, characterized in that the phosphonites (component F)) are those of the general structure         R-[P(OR5)2]m     (VI) where R is a mono- or polyvalent aliphatic, aromatic or heteroaromatic organic radical and R5 is a compound of the structure (VII) or the two R5 radicals form a bridging group of the structure (VIII) with A is a direct bond, O, S, C1-18-alkylene (linear or branched), C1-18-alkylidene (linear or branched), in which R6 is independently C1-12-alkyl (linear or branched), C1-12-alkoxy and / or C5-12-cycloalkyl and n is 0 to 5 and m is 1 to 4.

16. Flame-retardant polyamide composition according to one or more of Claims 1 to 15, characterized in that component G) comprises alkali metal, alkaline earth metal, aluminum and / or zinc salts of long-chain fatty acids having 14 to 40 carbon atoms and / or reaction products of long-chain fatty acids having 14 to 40 carbon atoms with polyhydric alcohols such as ethylene glycol, glycerol, trimethylolpropane and / or pentaerythritol.

17. Three-dimensional article comprising the composition according to one or more of Claims 1 to 16, characterized in that said article comprises shaped bodies, injection moldings, extrusion compounds and extrudates.

18. Use of a flame-retardant polyamide composition according to one or more of Claims 1 to 16 in or for plug connectors, current-bearing components in power distributors (residual current protection), circuit boards, potting compounds, plug connectors, circuit breakers, lamp housings (LED housings), capacitor housings, coil elements and ventilators for grounding contacts, plugs, in / on printed circuit boards, housings for plugs, cables, flexible circuit boards, charging cables for mobile phones, motor covers, textile coatings and other products.