Flame-retardant polyester compounds and their uses

Description

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

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

[0009] DE 10 2007 041 594 A1 discloses flame-retardant polyester compounds containing thermoplastic polyester, polycarbonate, phosphinic acid salt, and optionally reaction products of melamine with phosphoric acid and / or condensed phosphoric acids or other nitrogen-containing flame retardants, as well as optionally reinforcing materials and / or other additives. These compounds are characterized by a reliable UL 94 V-0 rating, increased glow-wire strength, improved mechanical properties, and reduced polymer degradation.

[0010] Further flame-retardant polyester compounds with this property profile are disclosed in DE 10 2010 049 968 A1. These compounds contain thermoplastic polyester, phosphinic acid salt, phosphazene, and optionally reaction products of melamine with phosphoric acid and / or condensed phosphoric acids or other nitrogen-containing flame retardants, and optionally reinforcing materials and / or other additives.

[0011] However, there is currently a lack of flame-retardant phosphinate-containing polyester 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 polyester compositions based on phosphinate-containing flame retardant systems which have all of the aforementioned properties simultaneously and which, in particular, have good electrical values ​​(GWFI, GWIT, CTI) and effective flame retardancy (UL-94), as well as good demoldability and a smooth surface of the molded part (surface).

[0013] Since waxes can usually form efflorescence, which causes rough surfaces, the results found regarding the smooth surface of the molded parts are particularly inventive.

[0014] The invention relates to a flame-retardant polyester composition containing 25 to 95 wt.% thermoplastic polyester 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 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, Fe, TiO q or Zn, n is 2 to 3, preferably 2 or 3, and q = (4 - n) / 2, 0.005 to 6 wt.% inorganic phosphonate as component F, and 0.05 to 5 wt.% wax selected from the group of polyolefin waxes, amide waxes, natural waxes, long-chain aliphatic carboxylic acids with a chain length of C 14 to C 40 (fatty acids) and / or their esters or salts as component G, the percentages being based on the total amount of the polyester composition.

[0015] In the polyester composition according to the invention, the proportion of component A is 25 to 95 wt.%, preferably 25 to 75 wt.%.

[0016] In the polyester composition according to the invention, the proportion of component B is 1 to 45 wt.%, preferably 20 to 40 wt.%.

[0017] In the polyester composition according to the invention, the proportion of component C is 1 to 35 wt.%, preferably 5 to 20 wt.%.

[0018] In the polyester composition according to the invention, the proportion of component D is 0.01 to 3 wt.%, preferably 0.05 to 1.5 wt.%.

[0019] In the polyester composition according to the invention, the proportion of component E is 0.001 to 1 wt.%, preferably 0.01 to 0.6 wt.%.

[0020] In the polyester composition according to the invention, the proportion of component F is 0.005 to 6 wt.%, preferably 0.05 to 2 wt.%.

[0021] In the polyester composition according to the invention, the proportion of component G is 0.05 to 5 wt.%, preferably 0.1 to 2 wt.%.

[0022] The percentages for the proportions of components A to G refer to the total amount of the polyester composition.

[0023] In the flame-retardant polyester 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 0.005 to 6 wt.%, and the proportion of component G 0.05 to 5 wt.%, where the percentages refer to the total amount of the polyester composition.

[0024] Particularly preferred are flame-retardant polyester compositions in which the proportion of component A is 25 to 75 wt.%, the proportion of component B is 20 to 40 wt.%, the proportion of component C is 5 to 20 wt.%, the proportion of component D is 0.05 to 1.5 wt.%, the proportion of component E is 0.01 to 0.6 wt.%, the proportion of component F is 0.05 to 2 wt.%, and the proportion of component G is 0.1 to 2 wt.%.

[0025] Preferred salts of component C are those in which M m+< Zn 2+< , Fe 3+< or in particular Al 3+<.

[0026] Preferred salts of component D are zinc, iron or, in particular, aluminum salts.

[0027] Preferred salts of component E are those in which Met n+< Zn 2+< , Fe 3+< or in particular Al 3+<.

[0028] Very particular preference is given to flame-retardant polyester compositions in which M and Met are Al, m and n are 3 and in which the compounds of components D and F are present as aluminum salts.

[0029] In a further preferred embodiment, the flame-retardant polyester compositions described above contain iron in an amount ranging from 0.0001 to 0.2 wt%, preferably from 0.0002 to 0.05 wt%.

[0030] The iron can be present in elemental form or in the form of an iron-containing alloy. However, the iron is preferably present in the form of an iron-containing substance, i.e., in the form of an ionic or non-ionic iron compound. For example, iron can be present as a cationic component in components C, D, E, and / or F, or other iron salts or iron complexes can be used.

[0031] Surprisingly, it was found that the polyester compositions according to the invention in the presence of iron have a broadened processing window during compounding or injection molding as well as improved thermal resistance, while at the same time providing good flame retardancy.

[0032] Particularly preferably, the flame retardant components C) to F) are present as a physical mixture with iron-containing compounds.

[0033] Also particularly preferably, at least one of the flame retardant components C), D), E) or F) contains iron.

[0034] The iron compounds for producing the polyester compositions according to the invention are preferably iron (II) and / or iron (III) salts.

[0035] In a further preferred embodiment, the polyester composition according to the invention contains as component H a melamine polyphosphate having an average degree of condensation of 2 to 200.

[0036] 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 H as flame retardants is known. For example, 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.

[0037] Preferred polyester compositions according to the invention contain as component H a melamine polyphosphate whose average degree of condensation is from 20 to 200, in particular from 40 to 150.

[0038] In another preferred range, the average degree of condensation is 2 to 100.

[0039] Further preferred polyester compositions according to the invention contain as component H 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.

[0040] 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 H.

[0041] 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.

[0042] 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.

[0043] In the polyester composition according to the invention, the proportion of component H is usually 0 to 25 wt.%, preferably 1 to 25 wt.%, in particular 2 to 10 wt.%, based on the total amount of the polyester composition.

[0044] In a further preferred embodiment, the polyester composition according to the invention contains melamine cyanurate as component I.

[0045] The melamine cyanurate used according to the invention as component I is known as a synergist in combination with diethyl phosphinates in flame retardants for polymeric molding compositions, for example from WO 97 / 39053 A1).

[0046] In the polyester composition according to the invention, the proportion of component I is usually 0 to 25 wt.%, preferably 1 to 25 wt.%, in particular 4 to 10 wt.%, based on the total amount of the polyester composition.

[0047] Flame-retardant polyester compositions according to the invention are preferred which have a Comparative Tracking Index, measured according to the International Electrotechnical Commission Standard IEC-60112 / 3, of greater than or equal to 500 volts.

[0048] Likewise preferred flame-retardant polyester 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.

[0049] Further preferred flame-retardant polyester 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.

[0050] Further preferred flame-retardant polyester compositions according to the invention have a glow wire resistance, expressed by the glow wire ignition temperature (GWIT) according to IEC-60695-2-13, of at least 775 °C, in particular measured on molded parts of 0.75 - 3 mm thickness.

[0051] The flame retardant combinations used according to the invention stabilize the polyester (component A) very effectively against thermal degradation. This is evident in the change in the specific viscosity of the polyester during compounding and molding of the polyester compositions according to the invention. The thermal stress resulting there results in a partial degradation of the polyester chains, which is expressed in a reduction in the average molecular weight and, consequently, in a reduction in the viscosity of a polyester solution. Typical values ​​for the specific viscosity of polybutylene terephthalate, measured as a 0.5% solution in phenol / dichlorobenzene (1:1) at 25 °C according to ISO 1628 using a capillary viscometer, are 130 cm³ / g.After compounding and shaping a polybutylene terephthalate composition according to the invention, typical values ​​for the specific viscosity of the processed polybutylene terephthalate (determined as stated above) are in the range between 65 and 150 cm 3 / g, preferably between 100 and 129 cm 3 / g.

[0052] The polyester compositions according to the invention contain one or more thermoplastic polyesters as component A.

[0053] The polyesters of component A are generally (cyclo)aliphatic or aromatic-aliphatic polyesters derived from (cyclo)aliphatic and / or aromatic dicarboxylic acids or their polyester-forming derivatives, such as their dialkyl esters or anhydrides, and from (cyclo)aliphatic and / or araliphatic diols or from (cyclo)aliphatic and / or aromatic hydroxycarboxylic acids or their polyester-forming derivatives, such as their alkyl esters or anhydrides. The term "(cyclo)aliphatic" encompasses cycloaliphatic and aliphatic compounds.

[0054] The thermoplastic polyesters of component A are preferably selected from the group of polyalkylene esters of aromatic and / or aliphatic dicarboxylic acids or their dialkyl esters.

[0055] The thermoplastic polyesters used as component A can be produced by known methods (Plastics Handbook, Vol. VIII, pages 695 - 710, Karl-Hanser-Verlag, Munich 1973).

[0056] Preferably used components A are aromatic-aliphatic thermoplastic polyesters and, preferably, thermoplastic polyesters derived therefrom by reacting aromatic dicarboxylic acids or their polyester-forming derivatives with aliphatic C 2 -C 10 diols, in particular with C 2 -C 4 diols.

[0057] Components A preferably used according to the invention are polyalkylene terephthalates, and of these, particularly preferably polyethylene terephthalates or polybutylene terephthalates.

[0058] Polyalkylene terephthalates preferably contain at least 80 mol%, in particular 90 mol%, based on the dicarboxylic acid, of units derived from terephthalic acid.

[0059] The polyalkylene terephthalates preferably used according to the invention as component A can contain, in addition to terephthalic acid residues, up to 20 mol% of residues of other aromatic dicarboxylic acids having 8 to 14 C atoms or residues of aliphatic dicarboxylic acids having 4 to 12 C atoms, such as residues of phthalic acid, isophthalic acid, naphthalene-2,6-dicarboxylic acid, 4,4'-diphenyldicarboxylic acid, succinic, adipic, sebacic or azelaic acid, cyclohexanediacetic acid or cyclohexanedicarboxylic acid.

[0060] The polyalkylene terephthalates preferably used as component A according to the invention can be branched by incorporating relatively small amounts of tri- or tetrahydric alcohols or tri- or tetrabasic carboxylic acids, as described, for example, in DE-A-19 00 270. Examples of preferred branching agents are trimesic acid, trimellitic acid, trimethylolethane and propane, and pentaerythritol.

[0061] Particularly preferred components A are polyalkylene terephthalates which are prepared solely from terephthalic acid and its reactive derivatives (e.g. its dialkyl esters) and ethylene glycol and / or 1,3-propanediol and / or 1,4-butanediol (polyethylene and polytrimethylene and polybutylene terephthalate) and mixtures of these polyalkylene terephthalates.

[0062] Preferred polybutylene terephthalates contain at least 80 mol%, preferably 90 mol%, based on the dicarboxylic acid, of terephthalic acid residues and at least 80 mol%, preferably at least 90 mol%, based on the diol component, of 1,4-butanediol residues.

[0063] The preferred polybutylene terephthalates may further contain, in addition to 1,4-butanediol residues, up to 20 mol% of other aliphatic diols having 2 to 12 C atoms or cycloaliphatic diols having 6 to 21 C atoms, e.g. residues of ethylene glycol; 1,3-propanediol; 2-ethyl-1,3-propanediol; neopentyl glycol; 1,5-pentanediol; 1,6-hexanediol; 1,4-cyclohexanedimethanol; 3-methyl-2,4-pentanediol; 2-methyl-2,4-pentanediol; 2,2,4-trimethyl-1,3-pentanediol; 2-ethyl-1,3-hexanediol; 2,2-diethyl-1,3-propanediol; 2,5-hexanediol; 1,4-di-([beta]-hydroxyethoxy)-benzene; 2,2-bis-(4-hydroxycyclohexyl)propane; 2,4-Dihydroxy-1,1,3,3-tetramethylcyclobutane; 2,2-bis-(3-[beta]-hydroxyethoxyphenyl)-propane and 2,2-bis-(4-hydroxypropoxyphenyl)-propane.

[0064] Polyalkylene terephthalates preferably used as component A according to the invention are also copolyesters which are prepared from at least two of the above-mentioned acid components and / or from at least two of the above-mentioned alcohol components and / or 1,4-butanediol.

[0065] The thermoplastic polyesters used as component A according to the invention can also be used in a mixture with other polyesters and / or other polymers.

[0066] Component B consists of fillers and / or reinforcing materials, preferably glass fibers. Mixtures of two or more different fillers and / or reinforcing materials can also be used.

[0067] 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.

[0068] 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.

[0069] 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.

[0070] 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.

[0071] 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.

[0072] Typical fiber lengths for short glass fibers before incorporation into the polyester matrix range from 0.05 to 10 mm, preferably from 0.1 to 5 mm. After incorporation into the polyester matrix, the length of the glass fibers has decreased. Typical fiber lengths for short glass fibers after incorporation into the polyester matrix range from 0.01 to 2 mm, preferably from 0.02 to 1 mm.

[0073] The diameters of individual fibers can vary widely. Typical diameters of individual fibers range from 5 to 20 µm.

[0074] 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.

[0075] Glass fibers can be used as continuous fibers or as chopped or milled glass fibers.

[0076] 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.

[0077] 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%.

[0078] 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%.

[0079] 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.

[0080] The salts of diethylphosphinic acid used according to the invention as component C are known flame retardants for polymeric molding compounds.

[0081] 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.

[0082] 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.

[0083] 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 DE 102007041594 A1.

[0084] The use of the inorganic phosphonates or phosphorous acid salts (phosphites) used according to the invention as component F 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.

[0085] The inorganic phosphonate (component F) 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.

[0086] The inorganic phosphonate (component F) 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.

[0087] The inorganic phosphonate (component F) is preferably also an aluminum phosphite of the formulas (VI), (VII) and / or (VIII) Al 2 (HPO 3 ) 3 x (H 2 O) q (VI), where q is 0 to 4, Al 2.00 M z (HPO 3 ) y (OH) vx (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 ) tx (H 2 O) s (VIII), where u is from 2 to 2.99, t is from 2 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.

[0088] Preferred inorganic phosphonates (component F) are salts that are insoluble or sparingly soluble in water.

[0089] Particularly preferred inorganic phosphonates are aluminum, calcium and zinc salts.

[0090] Component F is particularly preferably a reaction product of phosphorous acid and an aluminum compound.

[0091] Particularly preferred components F 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.

[0092] 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.

[0093] Preferred aluminum sources are aluminum isopropoxide, aluminum nitrate, aluminum chloride, aluminum hydroxide (e.g. pseudoboehmite).

[0094] Preferred phosphorus sources are phosphorous acid, (acidic) ammonium phosphite, alkali phosphites or alkaline earth phosphites.

[0095] Preferred alkali phosphites are disodium phosphite, disodium phosphite hydrate, trisodium phosphite, potassium hydrogen phosphite

[0096] The preferred disodium phosphite hydrate is Brüggolen ®< H10 from Brüggemann.

[0097] Preferred templates are 1,6-hexanediamine, guanidine carbonate or ammonia.

[0098] The preferred alkaline earth phosphite is calcium phosphite.

[0099] 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.

[0100] 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.

[0101] In a preferred embodiment, the flame-retardant polyester compositions described above contain as component F 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.

[0102] Preferred compounds of formula III are those in which Me o+< Zn 2+< , Fe 3+< or in particular Al 3+<.

[0103] In a further preferred embodiment, components C, D, E, F, H and I are in particle form, the average particle size (d 50 ) being 1 to 100 µm.

[0104] 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.

[0105] 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.

[0106] Mixtures of different waxes can also be used.

[0107] 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.

[0108] Polyolefin waxes preferably used as component G are PE waxes, PTFE waxes, PP waxes, FT paraffins, macro- and microcrystalline paraffins and polar polyolefin waxes.

[0109] 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.

[0110] 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.

[0111] 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.

[0112] 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.

[0113] 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.

[0114] 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 polyolefin waxes are those 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.

[0115] 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 14 to 40 carbon atoms, for example, stearic acid, tallow fatty acid, palmitic acid, or erucic acid.

[0116] Other waxes preferred for component G are natural waxes. These include carnauba wax and candelilla wax.

[0117] 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.

[0118] 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 C 22 to C 36 .

[0119] 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.

[0120] 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.

[0121] 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.

[0122] Component G most preferably comprises esters or salts of stearic acid, such as glycerol monostearate or pentaerythritol tetrastearate or calcium, aluminum or zinc stearate.

[0123] Component G most preferably comprises reaction products of montan wax acids with alkylene glycol, in particular with ethylene glycol.

[0124] 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.

[0125] Component G is also particularly preferably a reaction product of montan wax acids with a calcium, aluminum or zinc salt.

[0126] 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.

[0127] 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.

[0128] The polyester compositions according to the invention may contain further additives as component J. Preferred components J for the purposes 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, H, and I.

[0129] 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.

[0130] Melamine poly(metal phosphates) are preferably melamine poly(zinc phosphates), melamine poly(magnesium phosphates) and / or melamine poly(calcium phosphates).

[0131] 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 .

[0132] 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.

[0133] 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.

[0134] 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).

[0135] Preferred are aluminum phosphates, aluminum monophosphate, aluminum orthophosphate (AlPO 4 ), aluminum hydrogen phosphate (Al 2 (HPO 4 ) 3 ) and / or aluminum dihydrogen phosphate

[0136] Calcium phosphate, zinc phosphate, titanium phosphate and / or iron phosphate are also preferred

[0137] Calcium hydrogen phosphate, calcium hydrogen phosphate dihydrate, magnesium hydrogen phosphate, titanium hydrogen phosphate (TIHC) and / or zinc hydrogen phosphate are preferred

[0138] Preferred are aluminum dihydrogen phosphate, magnesium dihydrogen phosphate, calcium dihydrogen phosphate, zinc dihydrogen phosphate, zinc dihydrogen phosphate dihydrate and / or aluminum dihydrogen phosphate.

[0139] Particularly preferred are calcium pyrophosphate, calcium dihydrogen pyrophosphate, magnesium pyrophosphate, zinc pyrophosphate and / or aluminum pyrophosphate.

[0140] The aforementioned and other similar phosphates are offered, for example, by JM Huber Corporation, USA, under Safire ®< Products. These include APP Type II, AMPP, MPP, MPyP, PiPyP, PPaz, Safire ®< 400, Safire ®< 600, EDAP, and others.

[0141] Other phosphates are mentioned, for example, in JP-A-2004204194, DE-A-102007036465 and EP-A-3133112 and are expressly among the aforementioned usable components.

[0142] The other additives are known as additives to polyester compositions and can be used alone or in mixtures or in the form of masterbatches.

[0143] The aforementioned components A, B, C, D, E, F, G, and optionally H, I, and J can be processed in a wide variety of combinations to form the flame-retardant polyester composition according to the invention. It is thus possible to mix the components into the polyester 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.

[0144] Two or more of the components of the polyester compositions according to the invention can also be combined by mixing prior to incorporation into the polyester 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.

[0145] Granules can also be produced from two or more of the components of the polyester compositions according to the invention, which can then be introduced into the polyester matrix.

[0146] For this purpose, two or more components of the polyester composition according to the invention can be processed into granules with granulation aid and / or binder in a suitable mixer or a granulating plate.

[0147] The initially produced raw product can be dried in a suitable dryer or tempered for further grain formation.

[0148] In one embodiment, the polyester composition of the invention or two or more components thereof can be produced by roll compaction.

[0149] In one embodiment, the polyester composition according to the invention or two or more components thereof can be prepared by mixing the ingredients, extruding them, chipping them (or optionally breaking and classifying them) and drying them (and optionally coating them).

[0150] In one embodiment, the polyester composition according to the invention or two or more components thereof can be prepared by spray granulation.

[0151] 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.

[0152] Typical length-to-diameter ratios of the granules are 1 to 50 to 50 to 1, preferably 1 to 5 to 5 to 1.

[0153] 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.

[0154] The invention also relates to molded parts made from the flame-retardant polyester composition described above containing the

[0155] Components A, B, C, D, E, F and G and optionally component(s) H, I and J.

[0156] The molded parts according to the invention can be any desired shape. Examples include fibers, films, or molded articles obtainable from the flame-retardant polyester molding compounds according to the invention by any molding process, in particular by injection molding or extrusion.

[0157] The flame-retardant polyester moldings according to the invention can be produced by 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 polyester molding compound.

[0158] The molded parts are preferably injection molded parts or extrusion parts.

[0159] The flame-retardant polyester 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.

[0160] The invention preferably relates to the use of the flame-retardant polyester 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.

[0161] The invention also preferably relates to the use of the flame-retardant polyester 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.

[0162] 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.

[0163] The following examples illustrate the invention without limiting it. 1. Components used

[0164] Commercially available polyesters (component A): Polybutylene terephthalate (PBT): Ultradur ®< 4500 (BASF) Polyethylene terephthalate (PET): Polyclear ®< 1100 (Invista) Glass fibers (component B): Glass fibers Vectrotex ®< EC 10 P 952 (Vectrotex, FR) 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 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 produced according to example 4 of US 7,420,007 B2 Flame retardant FM 3 (components C, D and E): Aluminium salt of diethylphosphinic acid containing 0.5 mol% of aluminium ethyl butyl phosphinate and 0.05 mol% of aluminium ethyl phosphonate produced 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, produced by the process according to US 7,420,007 B2 Flame retardant FM 5 (component C): Aluminum salt of diethylphosphinic acid produced 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 F): Aluminum salt of phosphonic acid produced according to example 1 of DE 102011120218 A1 Flame retardant FM 8 (component F): Aluminum salt of phosphorous acid Flame retardant FM 9 (component H): Melamine polyphosphate produced according to the example of WO2000 / 002869 A1 Flame retardant FM 10 (Component I): Melamine cyanurate, Melapur ®< MC (BASF) Wax 1 (Component G): Licomont ®< CaV 102 (Ca salt of montan wax acid),Clariant Products (Germany) GmbH Wax 2 (component G): Licowax ®< E (ester of montan wax acid), Clariant Products (Germany) GmbH, 2. Production, processing and testing of flame-retardant polyester molding compounds

[0165] The flame retardant components were mixed with the polymer granules and wax in the ratios specified in the tables and incorporated in a twin-screw extruder (Leistritz ZSE 27 HP-44D) at temperatures ranging from 240 to 280 °C. The glass fibers were added via a side feed. The homogenized polymer strand was drawn off, cooled in a water bath, and then granulated.

[0166] After sufficient drying, the molding compounds were molded into test specimens on an injection molding machine (type Arburg 320 C / KT) at melt temperatures of 260 to 280 °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.

[0167] The Comparative Tracking Index of the molded parts was determined according to the International Electrotechnical Commission Standard IEC-60112 / 3.

[0168] The Glow Wire Flammability Index (GWFI index) was determined according to the standard IEC-60695-2-12.

[0169] The glow wire ignition temperature (GWIT index) was determined according to the standard IEC-60695-2-13.

[0170] In the GWFI test, the maximum temperature at which an afterburning time of 30 seconds is not exceeded and the sample does not drip off while burning is determined on three test specimens (for example, plates with a geometry of 60 x 60 x 1.5 mm) using a glowing wire at temperatures between 550 and 960 °C. In the GWIT test, a comparable measurement procedure is used to determine the glow-wire ignition temperature, which is 25 K (30 K 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.

[0171] The condition of the surface of the molded part was assessed visually.

[0172] 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. Examples 1 - 6 and comparative examples V1-V10 with PBT

[0173] The results of the tests with PBT molding compounds are listed in the examples in the table below. All amounts are given as wt.% and refer to the PBT molding compound including flame retardants, additives, and reinforcing materials. Table 1: PA 6.6 GF 30 test results (1-6 according to the invention; 1a, 1b and V1-V10 comparisons) Example No. 1 1a 1b V1 2 V2 3 V3 4 V4 5 V5 6 V6 V7 V8 V9 V10 A: PBT 51,3 51,8 51,8 51,5 51,3 51,5 51,3 51,5 51,3 51,5 53,78 53,98 51,3 51,5 51,3 51,8 47,8 51,3 B: Glass fibers EC10 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 C+D+E: FM 1 18 12 12 18 - - - - - - - - - - - - - - C+D+E: FM 2 - - - - 18 18 - - - - 16 16 18 18 - 18 22 - C+D+E: FM 3 - - - - - - 18 18 - - - - - - - - - - C+D+E: FM 4 - - - - - - - - 18 18 - - - - - - - - C: FM 5 - - - - - - - - - - - - - - - - - 18 C+E: FM 6 - - - - - - - - - - - - - - 18 - - - F: FM 7 - - - - - - - - - - 0,02 0,02 - - - - - - F: FM 8 0,5 - - 0,5 0,5 0,5 0,5 0,5 0,5 0,5 - - 0,5 0,5 0,5 - - 0,5 H: FM 9 - 6 - - - - - - - - - - - - - - - - I: FM 10 - - 6 - - - - - - - - - - - - - - - G: Wax 1 0,2 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 - - - - - UL 94 0.4mm / [sec.] V-0 / 20 V-0 / 21 V-0 / 24 V-0 / 20 V-0 / 15 V-0 / 15 V-0 / 35 V-0 / 35 V-0 / 20 V-0 / 20 V-0 / 05 V-0 / 05 V-0 / 10 V-0 / 10 V-0 / 40 V-2 / 90 V-1 / 75 V-0 / 45 GWFI [°C] 960 960 960 960 960 960 960 960 960 960 960 960 960 960 960 850 900 960 GWIT [°C] 750 750 750 750 750 750 750 750 750 750 750 725 750 700 750 700 725 750 CTI [volts] 600 600 600 500 600 500 600 500 600 500 600 500 550 500 500 600 600 500 surface smooth smooth smooth rough *)< smooth rough *)< smooth rough *)< smooth rough *)< smooth rough *)< smooth rough *)< Smooth smooth smooth smooth *)< massive problems when demolding the part from the mold

[0174] The inventive polyester compositions of Examples 1 to 6 are molding compounds that achieve UL 94 V-0 flame classification at 0.4 mm, while simultaneously exhibiting CTIs of 600 volts and 550 volts, GWFIs of 960 °C, and GWITs of 750 °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 an additional component F in Example 5 leads to a further improvement in flame retardancy, expressed by a reduced afterburn time.

[0175] 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.

[0176] The omission of component D in comparative example V7 resulted in a prolonged afterburning time and a reduced CTI value compared to examples 1-4.

[0177] The omission of component F in comparative example V8 resulted in reduced GWFI and GWIT values ​​in addition to a deterioration in the fire protection class compared to example 2.

[0178] In Comparative Example V9, an improvement in the fire protection class was achieved by increasing the concentration of components C, D, and E compared to Example V8. However, this polyester composition still exhibited a lower fire protection class and reduced GWFI and GWIT values ​​compared to Example 2.

[0179] The omission of components D and E in comparative example V10 resulted in a longer afterburn time and a reduced CTI value compared to examples 1-4. Examples 7-12 and comparative examples V11-V20 with PET

[0180] The results of the tests with PET molding compounds are listed in the examples in the table below. All amounts are given as wt.% and refer to the polyester molding compound including flame retardants, additives, and reinforcing materials. Table 2: PET GF 30 test results (7-12 according to the invention; V11-V20 comparisons) Example No. 7 V11 8 V12 9 V13 10 V14 11 V15 12 V16 V17 V18 V19 V20 A: PET 57,3 57,5 57,3 57,5 57,3 57,5 57,3 57,5 57,3 57,5 57,3 57,5 57,3 57,8 52,8 57,3 B: Glass fibers EC10 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 17 - C+D+E: FM 3 - - - - 12 12 - - - - - - - - - - C+D+E: FM 4 - - - - - - 12 12 - - - - - - - - C: FM 5 - - - - - - - - - - - - - - - 12 C+E: FM 6 - - - - - - - - - - - - 12 - - - F: FM 7 - - - - - - - - 2 2 - - - - - - F: FM 8 0,5 0,5 0,5 0,5 0,5 0,5 0,5 0,5 0,5 0,5 0,5 0,5 0,5 - - 0,5 G: Wax 1 0,2 - 0,2 - 0,2 - 0,2 - 0,2 - - - 0,2 0,2 0,2 0,2 G: Wax 2 - - - - - - - - - - 0,2 - - - - - UL 94 0.4mm / [sec.] V-0 / 18 V-0 / 18 V-0 / 12 V-0 / 12 V-0 / 32 V-0 / 32 V-0 / 16 V-0 / 16 V-0 / 03 V-0 / 03 V-0 / 08 V-0 / 08 V-0 / 35 V-2 / 85 V-1 / 70 V-0 / 39 GWFI [°C] 960 960 960 960 960 960 960 960 960 960 960 960 960 850 900 960 GWIT [°C] 775 750 775 750 800 750 750 675 750 750 775 750 750 725 750 750 CTI [volts] 600 500 600 500 600 500 600 500 600 500 550 500 500 600 600 500 surface Smooth rough *)< smooth rough *)< smooth rough *)< smooth rough *)< smooth rough *)< smooth rough *)< smooth smooth smooth Smooth *)< massive problems when demolding the part from the mold

[0181] The inventive polyester compositions of Examples 7 to 12 are molding compounds that achieve UL 94 V-0 flame classification at 0.4 mm, while simultaneously exhibiting CTI values ​​of 600 volts or 550 volts, GWFI of 960 °C or GWIT of 750-775 °C, and 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 an additional component F in Example 11 leads to a further improvement in flame retardancy, expressed by a reduced afterburn time.

[0182] Omitting component G in comparative examples V11 to V16 resulted in molded parts with rough surfaces that were also difficult to demold. Flame resistance, GWFI, and GWIT 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.

[0183] The omission of component D in comparative example V17 resulted in a prolonged afterburning time and a reduced CTI value compared to examples 7-10.

[0184] The omission of component F in comparative example V18 resulted in reduced GWFI and GWIT values ​​in addition to a deterioration in the fire protection class compared to example 8.

[0185] In Comparative Example V19, an improvement in the fire protection class was achieved by increasing the concentration of components C, D, and E compared to Example V18. However, this polyester composition still exhibited a lower fire protection class and reduced GWFI and GWIT values ​​compared to Example 8.

[0186] The omission of components D and E in comparative example V20 resulted in a prolonged afterburn time and a reduced CTI value compared to examples 7-10. Examples 13-15

[0187] The production, processing, and testing of flame-retardant polyester molding compounds and molded polyester articles was carried out as described in Examples 1-12 and V1-V20. Flame-retardant polyester molding compounds and molded polyester articles were produced according to the aforementioned general procedure.

[0188] Their composition was 51.3 wt.% polybutylene terephthalate (Ultradur ®< 4500), 30 wt.% glass fibers (Vectrotex ®< EC 10 P 952), 18 wt.% flame retardants of components C, D and E used according to the invention in accordance with the following information, 0.5 wt.% aluminum salt of phosphorous acid, and 0.2 wt.% wax (Licowax ®< E).

[0189] The thermal stability of the polyester compositions tested was determined using thermogravimetry (TGA). The temperature given is the temperature at which a 2% weight loss occurs.

[0190] The processing window of the investigated polyester compositions was also determined using TGA. The weight loss is measured in wt. % at 330 °C after 1 h. TGA is performed under air atmosphere.

[0191] Since the lower limit of the processing window is not affected, the decomposition of the flame-retardant polyester molding compound at the upper limit is determined as a measure of the processing window. This is determined by the weight loss at a defined temperature. Example 13

[0192] The flame retardant used was the above-described FM 2, which consisted of components C), D), and E) in the form of aluminum salts. A thermal resistance of 325°C and a processing window of 8% were determined. Example 14

[0193] A modified FM 2 was used as the flame retardant, in which some of the Al cations had been replaced by Fe cations. The total iron content was 20 ppm. A thermal resistance of 335°C and a processing window of 5% were determined. Example 15

[0194] A modified FM 2 was used as the flame retardant, in which some of the Al cations had been replaced by Fe cations. The total iron content was 1000 ppm. A thermal resistance of 375°C and a processing window of 4.5% were determined.

Claims

1. Flame-retardant polyester compositions comprising - 25% to 95% by weight of thermoplastic polyester 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, Fe, TiOq or Zn, n is 2 to 3, and q = (4 - n) / 2, - 0.005% to 6% by weight of inorganic phosphonate as component F, and - 0.05% to 5% by weight of wax selected from the group consisting of the polyolefin waxes, amide waxes, natural waxes, long-chain aliphatic carboxylic acids having a chain length of C14 to C40 and / or esters or salts thereof as component G, where the percentages are based on the total amount of the polyester composition.

2. Flame-retardant polyester compositions according to Claim 1, characterized in that M and Met are Al, m and n are 3, and in that components D and F are aluminum salts.

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

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

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

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

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

8. Flame-retardant polyester compositions according to Claim 1, characterized in that the proportion of component F is 0.05% to 2% by weight.

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

10. Flame-retardant polyester compositions according to at least one of Claims 1 to 9, characterized in that the polyester compositions contain iron in an amount within the range from 0.0001% to 0.2% by weight, preferably from 0.0002% to 0.05% by weight.

11. Flame-retardant polyester compositions according to Claim 10, characterized in that at least one of the flame-retardant components C), D), E) and F) contains iron.

12. Flame-retardant polyester compositions according to at least one of Claims 1 to 11, characterized in that said polyester compositions comprise a melamine polyphosphate having an average degree of condensation of 2 to 200 as component H, preferably a melamine polyphosphate having an average degree of condensation of 20 to 200.

13. Flame-retardant polyester compositions according to at least one of Claims 1 to 12, characterized in that said polyester compositions comprise melamine cyanurate as component I.

14. Flame-retardant polyester compositions according to at least one of Claims 1 to 13, characterized in that it has a comparative tracking index measured according to International Electrotechnical Commission Standard IEC-60112 / 3 of not less than 500 V.

15. Flame-retardant polyester compositions according to at least one of Claims 1 to 14, characterized in that it attains a UL-94 V-0 assessment at thickness from 3.2 mm to 0.4 mm.

16. Flame-retardant polyester compositions according to at least one of Claims 1 to 15, characterized in that it has a glow wire flammability index according to IEC-60695-2-12 of at least 960°C at thickness 0.75-3 mm.

17. Flame-retardant polyester compositions according to at least one of Claims 1 to 16, characterized in that it has a glow wire ignition temperature according to IEC-60695-2-13 of at least 750°C at thickness 0.75-3 mm.

18. Flame-retardant polyester compositions according to at least one of Claims 1 to 17, characterized in that component A comprises one or more polyalkylene terephthalates.

19. Flame-retardant polyester compositions according to Claim 18, characterized in that component A is a polyethylene terephthalate.

20. Flame-retardant polyester compositions according to Claim 18, characterized in that component A is a polybutylene terephthalate.

21. Flame-retardant polyester compositions according to Claim 20, characterized in that the specific viscosity of the polybutylene terephthalate, measured as a 0.5% solution in phenol / dichlorobenzene (1:1) at 25°C to ISO 1628 with a capillary viscometer, is within the range between 65 and 150 cm3 / g, preferably between 100 and 129 cm3 / g.

22. Flame-retardant polyester compositions according to at least one of Claims 1 to 21, characterized in that glass fibers are used as component B.

23. Flame-retardant polyester compositions according to at least one of Claims 1 to 22, characterized in that the polyester compositions comprise an inorganic phosphonate of the formula (III) as component F in which Me is Fe, TiOr, Zn or especially Al, o is 2 to 3, and r = (4 - o) / 2.

24. Flame-retardant polyester compositions according to at least one of Claims 1 to 23, 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.

25. Flame-retardant polyester compositions according to at least one of Claims 1 to 23, characterized in that component G is a polyamide wax which has been prepared by reaction of ammonia or alkylenediamine with saturated and / or unsaturated fatty acids having 14 to 40 carbon atoms.

26. Flame-retardant polyester compositions according to at least one of Claims 1 to 25, characterized in that said polyester composition comprises further additives as component J, 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, F, H and I.

27. Use of the polyester compositions according to one of Claims 1 to 26 for production of fibers, films and moldings, especially for uses in the electricals and electronics sector.