Flame Retardant Polyester Blend

Abstract

A thermoplastic molding composition comprising a thermoplastic polyester, poly(ε-caprolactone), a biodegradable polyester different from poly(ε-caprolactone), a phosphinate, and a polar modified polyolefin wax prepared by a metallocene catalyst, the use of the thermoplastic molding composition for producing any type of flame-retardant molded article, the resulting molded article, and the use of a polar modified polyolefin wax prepared by a metallocene catalyst for improving the flame retardancy of a thermoplastic molding composition comprising a thermoplastic polyester.

Description

[0001] The present invention relates to a thermoplastic molding composition comprising a thermoplastic polyester, poly(ε-caprolactone), a biodegradable polyester different from poly(ε-caprolactone), a phosphinate, and a polar modified polyolefin wax prepared by a metallocene catalyst, to the use of the thermoplastic molding composition for producing any type of flame-retardant molded article, to the resulting molded article, and to the use of a polar modified polyolefin wax prepared by a metallocene catalyst for improving the flame retardancy of a thermoplastic molding composition comprising a thermoplastic polyester.

[0002] Thermoplastic polyesters are materials with a long history of use. In addition to the mechanical, thermal, electrical, and chemical properties of these materials, properties such as flame retardancy and high glow wire resistance are becoming increasingly important factors. Examples here are applications in the field of household products (such as plugs) and the electronics field (such as protective covers for circuit breakers).

[0003] Furthermore, the market is showing an increasing interest in thermoplastic polyesters with a halogen-free flame retardant system. Important requirements for the flame retardant here are a light inherent color, sufficient thermal stability during polymer processing, and effective flame retardancy in reinforced and unreinforced polymers.

[0004] The effectiveness of a halogen-free flame retardant additive mixture consisting of a phosphinate and a nitrogen-containing synergist and the reaction product of melamine and phosphoric acid (melamine polyphosphate) is basically described by the UL 94V combustion test; see EP-A142 3260, EP-A 108 4181.

[0005] DE-A-199 60 671 describes not only conventional flame retardants such as phosphinates and melamine compounds, but also combinations with metal oxides, with metal hydroxides, or with other salts.

[0006] A specific problem with these formulations is their mechanical properties including brittleness, which often leads to premature breakage (elongation at break) during use. Various methods based on polymer blends have been described: the use of commercially available impact modifiers (commercial products such as ) leads to a significant improvement in mechanical properties, but it becomes impossible to achieve flame-retardant products with a low wall thickness. The reason is that the additives are highly flammable and are largely based on ethylene or butadiene. Therefore, tough flame-retardant products are usually achieved by mixtures of PBT with various elastomers (US2008 / 0167406 and EP-A-2476730), but the same disadvantages occur here.

[0007] WO 2006 / 018127 describes polyester mixtures which contain not only flow improvers but also rubbers as impact modifiers. These mixtures can improve the mechanical properties, but the addition of rubbers impairs the rheological properties.

[0008] The commercially available flame retardant ABS and PC additives resorcinol bis(diphenyl phosphate) (RDP, CAS: 57583-54-7) and bisphenol A diphenyl phosphate (BDP, CAS: 5945-33-5) exhibit disadvantages with regard to migration (see Polymer Degradation and Stability, 2002, 77(2), pages 267 - 272).

[0009] WO 2017 / 063841 A1 describes thermoplastic polyester molding compositions which have a halogen - free flame retardant system and have good mechanical properties (elongation at break) and flame retardant properties. Additionally, the processing and the migration behavior of the additives during processing and in the desired applications (especially for thin - walled parts) are improved.

[0010] However, there is a need for further improvement in the flame retardant properties and for good processability at the same time, especially in extrusion.

[0011] Accordingly, an object of the present invention is to provide a polyester molding composition which has a halogen - free flame retardant system and is characterized in particular by good flame retardant properties, especially for thin - walled parts. The processing should also be improved, especially in extrusion.

[0012] Accordingly, the following molding compositions have been found.

[0013] A thermoplastic molding composition comprising

[0014] A) 10 to 99.65% by weight of a thermoplastic polyester different from C);

[0015] B) 0.1 to 30% by weight of poly(ε - caprolactone);

[0016] C) 0.1 to 30% by weight of a biodegradable polyester different from B);

[0017] D) 0.1 to 30% by weight of a phosphinate;

[0018] E) 0 to 20% by weight of a nitrogen - containing flame retardant;

[0019] F) 0 to 15% by weight of an aromatic phosphate having at least one alkyl - substituted benzene ring;

[0020] G) 0.05 to 1% by weight of a polyolefin wax prepared by a metallocene catalyst, wherein the polyolefin wax is a homopolymer of ethylene, a copolymer of ethylene with one or more 1-olefins which may be linear or branched, substituted or unsubstituted and have 3 to 18 carbon atoms, or a homopolymer of propylene, which is polar-modified by reacting the polyolefin wax with an α,β-unsaturated carboxylic acid or a derivative thereof;

[0021] H) 0 to 50% by weight of other additional substances,

[0022] wherein the sum of the weight percentages of components A) to H) is 100%.

[0023] Component G

[0024] The thermoplastic molding composition according to the invention is particularly characterized in that the amount of component G present is 0.05 to 1% by weight, preferably 0.07 to 0.7% by weight, more preferably 0.1 to 0.5% by weight of a polyolefin wax prepared by a metallocene catalyst, based on the total weight of the molding composition, wherein the polyolefin wax is a homopolymer of ethylene; a copolymer of ethylene with one or more 1-olefins which may be linear or branched, substituted or unsubstituted and have 3 to 18 carbon atoms; or a homopolymer of propylene, which is polar-modified by reacting the polyolefin wax with an α,β-unsaturated carboxylic acid or a derivative thereof.

[0025] Although processing aids such as long-chain fatty acids such as montan wax (a mixture of linear saturated carboxylic acids with a chain length of 28 to 32 carbon atoms) generally have a negative impact on the combustion behavior, the inventors of the present invention have found that the polar-modified polyolefin wax prepared by a metallocene catalyst has a positive impact on the combustion behavior, especially for thin-walled parts. In addition, the processing, especially in extrusion, is improved, i.e., there is no or reduced deposition of additives during the processing, especially no or reduced die drool.

[0026] The 1-olefin may be linear or branched, substituted or unsubstituted and have 3 to 18 carbon atoms, preferably 3 to 6 carbon atoms. Examples are propylene, 1-butene, 1-hexene, 1-octene and 1-octadecene, and styrene. Preferred is a copolymer of ethylene with propylene or 1-butene. The ethylene content of the copolymer is 70 to 99.9% by weight, preferably 80 to 99% by weight. If the 1-olefin is substituted, the substituent is preferably an aromatic group conjugated to the double bond of the 1-olefin.

[0027] Particularly suitable polyolefin waxes as starting materials, i.e., non-polar modified polyolefin waxes, are homopolymers of ethylene or copolymers of ethylene with one or more 1-olefins, preferably having a drop point of 90 - 130 °C, more preferably 100 - 120 °C, a melt viscosity at 140 °C preferably of 10 to 10,000 mPa·s, more preferably 50 to 5000 mPa·s, and a density at 20 °C preferably of 0.89 to 1.05 g / cm 3 , more preferably 0.91 to 0.99 g / cm 3 . In the case of copolymers of ethylene with one or more 1-olefins as comonomers, the comonomer units can be mainly randomly distributed or mainly block distributed. In the case where the 1-olefin is propylene, the propylene sequences can be isotactic, syndiotactic or partly atactic.

[0028] Other suitable polyolefin waxes as starting materials, i.e., non-polar modified polyolefin waxes, are propylene homopolymers prepared using metallocene catalysts and preferably having a melt viscosity of 20 to 50,000 mPa·s measured at 170 °C. The softening point (ring / ball) of such waxes is usually 90 to 165 °C, preferably 90 to 145 °C. Suitable waxes include both highly crystalline products with a high proportion of isotactic or syndiotactic structures and products with low crystallinity and mainly atactic structures. The crystallinity of the propylene homopolymer can be varied within a wide range in a known manner by appropriately selecting the catalyst used for polymerization and by means of the polymerization conditions.

[0029] The synthesis of unmodified (i.e., non-polar) starting waxes by metallocene-type catalysts is known from many documents, for example from EP-A-0 571 882 and EP-A-0 416 566.

[0030] The metallocene catalyst used for preparing the starting polyolefin wax is a chiral or achiral transition metal compound of the formula M 1 L x . The transition metal compound M 1 L x contains at least one central metal atom M 1 , and at least one π ligand (such as a cyclopentadienyl ligand) is bonded to the central metal atom M 1 . In addition, substituents such as halogen atoms or alkyl, alkoxy or aryl groups can be bonded to the central metal atom M 1 . M 1Preferably, the element is from main groups III, IV, V or VI of the periodic table, such as Ti, Zr or Hf. For the purposes of the present invention, the cyclopentadienyl ligands are unsubstituted cyclopentadienyl and substituted cyclopentadienyl, such as methylcyclopentadienyl, indenyl, 2-methylindenyl, 2-methyl-4-phenylindenyl, tetrahydroindenyl or octahydrofluorenyl. The π-ligands can be bridged or unbridged, where single and multiple bridges (including bridges via ring systems) are possible. The term metallocene also encompasses compounds having more than one metallocene fragment, called polynuclear metallocenes. These can have any substitution pattern and bridging form. The individual metallocene fragments of such polynuclear metallocenes can be of the same type or different from one another. Examples of such polynuclear metallocenes are described, for example, in EP-A-0 632 063.

[0031] Structural formulas of metallocenes and examples of their activation by cocatalysts are given, inter alia, in EP-A-0 571 882 and EP-A-0 416 566.

[0032] Preferably, the polyolefin wax is polar-modified by reacting the polyolefin wax with an α,β-unsaturated carboxylic acid or a derivative thereof in the presence of a radical former.

[0033] Examples of suitable α,β-unsaturated carboxylic acids or derivatives thereof are acrylic acid or methacrylic acid or their esters or amides, maleic acid, maleic anhydride, mono-esters of maleic acid (such as mono-alkyl maleates), di-esters of maleic acid (such as di-alkyl maleates) or amides of maleic acid (such as maleimide or N-alkyl-substituted maleimides). Mixtures of these compounds can also be used. Maleic acid and its derivatives are preferred; maleic anhydride is particularly preferred. The amount of the α,β-unsaturated carboxylic acid or its derivative is 0.1 to 20% by weight based on the starting polyolefin wax.

[0034] Suitable radical formers are compounds which decompose into radicals to a sufficient extent under the reaction conditions. Particularly suitable radical formers are organic peroxides, such as alkyl, aryl or arylalkyl peroxides, such as di-tert-butyl peroxide or dicumyl peroxide; peroxy esters, such as tert-butyl peracetate or tert-butyl perbenzoate such as tert-butyl hydroperoxide or cumene hydroperoxide. Other possible radical formers are aliphatic azo compounds, such as azobis(2-methylpropionitrile) or 2,2'-azobis(2,4-dimethylvaleronitrile). Dialkyl peroxides are preferred; di-tert-butyl peroxide is particularly preferred. The use concentration of the radical former, based on the starting polyolefin wax, is 0.1 to 5% by weight.

[0035] The reaction of the starting polyolefin wax with an α,β-unsaturated carboxylic acid or its derivative can be carried out continuously or batchwise. In the batch process, the wax is heated to a temperature above its softening point, and both the α,β-unsaturated carboxylic acid or its derivative and the radical former are introduced into the melt while stirring, continuously or in one or more portions over a suitable period of time, if necessary under an inert gas blanket. The reaction temperature is above the softening point of the wax, preferably 100 to 200 °C, particularly preferably 130 to 180 °C. After the metering addition is complete, the mixture can be further reacted at the same or a different temperature, if necessary after adding an additional amount of the radical former. The volatile components formed during the reaction or the excess volatile starting components can be removed, for example, by distillation under reduced pressure or by stripping with an inert gas.

[0036] The polar wax, i.e., component G of the present invention, preferably has an acid value or saponification value of 0.5 to 120 mg KOH / g, more preferably 1 to 100 mg KOH / g, most preferably 5 to 80 mg KOH / g, a melt viscosity of preferably 20 to 50,000 mPa·s, more preferably 25 to 5,000 mPa·s, most preferably 30 to 500 mPa·s, and a preferred softening point (ring / ball) of 90 to 165 °C, preferably 90 to 145 °C.

[0037] Preferably, component G) is a homopolymer of ethylene or a copolymer of ethylene with one or more 1-olefins which may be linear or branched, substituted or unsubstituted and have 3 to 18 carbon atoms, and which is polar-modified by reacting the polyolefin wax with maleic anhydride. More preferably, it is a homopolymer of ethylene which is polar-modified by reacting the polyolefin wax with maleic anhydride.

[0038] Products of this type are commercially available, for example, as PE MA 4221 fine granules from Clariant Plastics & Coatings (Deutschland) GmbH.

[0039] Component A

[0040] The molding composition of the present invention comprises 10 to 99.65% by weight, preferably 20 to 92.83% by weight, in particular 35 to 86.8% by weight, of at least one thermoplastic polyester different from B) or C) as component (A), based on the total weight of the molding composition.

[0041] Polyesters A) based on aromatic dicarboxylic acids and aliphatic and / or aromatic dihydroxy compounds are generally used.

[0042] Polyesters based on aromatic dicarboxylic acids and aliphatic dihydroxy compounds are preferred, in particular those aliphatic dihydroxy compounds having 2 to 10 carbon atoms are a first group of preferred polyesters.

[0043] These polyesters based on aromatic dicarboxylic acids and aliphatic dihydroxy compounds are known per se and are described in the literature. They contain aromatic rings derived from aromatic dicarboxylic acids in the main chain. The aromatic rings can also be substituted, for example, by halogens such as chlorine and bromine, or by C1-C4-alkyl groups such as methyl, ethyl, isopropyl, n-propyl, n-butyl, isobutyl, and tert-butyl.

[0044] These polyesters based on aromatic dicarboxylic acids and aliphatic dihydroxy compounds can be prepared (in a manner known per se) by the reaction of aromatic dicarboxylic acids or their esters or other ester-forming derivatives with aliphatic dihydroxy compounds.

[0045] Preferred dicarboxylic acids that may be mentioned are 2,6-naphthalenedicarboxylic acid, terephthalic acid, isophthalic acid, and mixtures thereof. Up to 30 mol%, preferably not more than 10 mol%, of the aromatic dicarboxylic acids can be replaced by aliphatic or cycloaliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, and cyclohexanedicarboxylic acid. Terephthalic acid is more preferably used as the dicarboxylic acid, i.e., the more preferred polyester (A) is an alkylene terephthalate.

[0046] Among the aliphatic dihydroxy compounds, diols having 2 to 6 carbon atoms are preferred, especially 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,4-hexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, and neopentyl glycol, and mixtures thereof.

[0047] Particularly preferred polyesters (A) that may be mentioned are alkylene terephthalates derived from alkanediols having 2 to 6 carbon atoms. Among them, polyethylene terephthalate, polypropylene terephthalate, and polybutylene terephthalate, and mixtures thereof are particularly preferred. PET and / or PBT are also preferred, which contain up to 1% by weight, preferably up to 0.75% by weight, of 1,6-hexanediol and / or 2-methyl-1,5-pentanediol as additional monomer units.

[0048] The intrinsic viscosity of the polyester (A) is generally 50 to 220, preferably 80 to 160 (measured in a 0.5% by weight solution in a phenol / o-dichlorobenzene mixture (weight ratio 1:1 at 25 °C) according to ISO 1628).

[0049] Particularly preferred are polyesters having a carboxyl end group content of at most 100 meq / kg of polyester, preferably at most 50 meq / kg, and especially at most 40 meq / kg. These polyesters can be prepared, for example, by the method of DE-A 44 01 055. The carboxyl end group content is generally determined by a titration method (for example, potentiometry).

[0050] Furthermore, it is advantageous to use PET recyclates (also known as waste PET), optionally mixed with polyalkylene terephthalates such as PBT.

[0051] The term recyclates generally means:

[0052] 1) Those known as post-industrial recyclates: These are production wastes during polycondensation or processing, such as runners from injection molding, starting materials from injection molding or extrusion, or scraps from extruded sheets or films.

[0053] 2) Post-consumer recyclates: These are plastic articles collected and processed after being utilized by the end consumer. Blow-molded PET bottles for mineral water, soft drinks, and fruit juices are easily the main articles in terms of quantity.

[0054] Both types of recyclates can be used as regrind or in the form of pellets. In the latter case, the crude recycled material is separated and purified, and then melted and pelletized using an extruder. This is generally beneficial for handling and free-flow properties, as well as metering for further steps in processing.

[0055] The length of the scraps should not be greater than 10 mm, preferably less than 8 mm.

[0056] Since polyesters undergo hydrolysis cracking during processing (due to trace amounts of moisture), it is recommended to pre-dry the recycled material. The residual moisture content after drying is preferably <0.2%, especially <0.05%.

[0057] Another group to be mentioned is wholly aromatic polyesters derived from aromatic dicarboxylic acids and aromatic dihydroxy compounds.

[0058] Suitable aromatic dicarboxylic acids are the compounds mentioned above for polyesters based on aromatic dicarboxylic acids and aliphatic dihydroxy compounds. A mixture of 5 to 100 mol% of isophthalic acid and 0 to 95 mol% of terephthalic acid is preferably used, especially a mixture of about 80% to 50% of terephthalic acid and 20% to 50% of isophthalic acid.

[0059] The aromatic dihydroxy compounds preferably have the general formula

[0060]

[0061] where Z is an alkylene or cycloalkylene group having at most 8 carbon atoms, an arylene group having at most 12 carbon atoms, a carbonyl group, a sulfonyl group, an oxygen atom or a sulfur atom, or a chemical bond, and where the value of m is from 0 to 2. The phenylene groups in the compounds can also be substituted by C1-C6-alkyl or alkoxy groups and fluorine, chlorine, or bromine.

[0062] Examples of the parent compounds of these compounds are

[0063] · Dihydroxybiphenyl,

[0064] · Bis(hydroxyphenyl)alkane,

[0065] · Bis(hydroxyphenyl)cycloalkane,

[0066] · Bis(hydroxyphenyl)sulfide,

[0067] · Bis(hydroxyphenyl)ether,

[0068] · Bis(hydroxyphenyl)ketone,

[0069] · Bis(hydroxyphenyl)sulfoxide,

[0070] · α,α’-Bis(hydroxyphenyl)dialkylbenzene,

[0071] · Bis(hydroxyphenyl)sulfone,

[0072] · Bis(hydroxybenzoyl)benzene,

[0073] · Resorcinol and hydroquinone,

[0074] · And their ring-alkylated and ring-halogenated derivatives.

[0075] Among them, preferably

[0076] · 4,4’-Dihydroxybiphenyl,

[0077] · 2,4-Bis(4’-hydroxyphenyl)-2-methylbutane,

[0078] · α,α’-Bis(4-hydroxyphenyl)-p-diisopropylbenzene,

[0079] · 2,2-Bis(3’-methyl-4’-hydroxyphenyl)propane, and

[0080] · 2,2-Bis(3’-chloro-4’-hydroxyphenyl)propane,

[0081] And especially

[0082] · 2,2-Bis(4’-hydroxyphenyl)propane,

[0083] · 2,2-Bis(3’,5-dichlorodihydroxyphenyl)propane,

[0084] · 1,1-Bis(4’-hydroxyphenyl)cyclohexane,

[0085] · 3,4’-Dihydroxybenzophenone,

[0086] · 4,4’-Dihydroxydiphenyl sulfone and

[0087] · 2,2-bis(3’,5’-dimethyl-4’-hydroxyphenyl)propane

[0088] or mixtures thereof.

[0089] Of course, mixtures of polyesters and wholly aromatic polyesters based on aromatic dicarboxylic acids and aliphatic dihydroxy compounds can also be used. These generally contain 20 to 98% by weight of an alkylene terephthalate and 2 to 80% by weight of a wholly aromatic polyester.

[0090] Of course, polyester block copolymers, such as copolyether esters, can also be used.

[0091] Products of this type are known per se and are described in the literature, for example in US Patent No. 3,651,014. Corresponding products are also commercially available, for example (DuPont).

[0092] Halogen-free polycarbonates are also polyesters in the context of the present invention. Examples of suitable halogen-free polycarbonates are those based on bisphenols of the following general formula:

[0093]

[0094] where Q is a single bond, C1-C8-alkylene, C2-C3-alkylene, C3-C6-cycloalkylene, C6-C 12 -arylene, or -O-, -S- or -SO2-, and m is an integer from 0 to 2.

[0095] The phenylene group of the bisphenol can also have substituents, such as C1-C6-alkyl or C1-C6-alkoxy.

[0096] Examples of preferred bisphenols of the above formula are hydroquinone, resorcinol, 4,4'-dihydroxybiphenyl, 2,2-bis(4-hydroxyphenyl)propane, 2,4-bis(4-hydroxyphenyl)-2-methylbutane and 1,1-bis(4-hydroxyphenyl)cyclohexane. 2,2-bis(4-hydroxyphenyl)propane and 1,1-bis(4-hydroxyphenyl)cyclohexane, and 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane are particularly preferred.

[0097] Homopolycarbonates or copolycarbonates are also suitable as component A), and copolycarbonates of bisphenol A and bisphenol A homopolymers are preferred.

[0098] Suitable polycarbonates can be branched in a known manner, specifically and preferably by introducing 0.05 to 2.0 mol% of at least trifunctional compounds, such as those having three or more phenolic OH groups, based on the total amount of bisphenol used.

[0099] Polycarbonates which have proven to be particularly suitable have a relative viscosity η of 1.10 to 1.50, in particular 1.25 to 1.40 rel n. This corresponds to an average molar mass M w (weight average) of 10,000 to 200,000 g / mol, preferably 20,000 to 80,000 g / mol. The bisphenols of the general formula are known per se or can be prepared by known methods.

[0100] The polycarbonates can be prepared, for example, by reacting a bisphenol with phosgene in an interfacial process or with phosgene in a homogeneous process (the so-called pyridine process), and in each case the desired molecular weight is achieved in a known manner by using a suitable amount of a known chain terminator (for polycarbonates containing polydiorganosiloxanes, see, for example, DE-A 33 34 782).

[0101] Examples of suitable chain terminators are phenol, p-tert-butylphenol or long-chain alkylphenols, such as 4-(1,3-tetramethylbutyl)phenol, as in DE-A 28 42 005, or monoalkylphenols, or dialkylphenols having a total of 8 to 20 carbon atoms in the alkyl substituents, as in DE-A 35 06 472, such as p-nonylphenyl, 3,5-di-tert-butylphenol, p-tert-octylphenol, p-dodecylphenol, 2-(3,5-dimethylheptyl)phenol and 4-(3,5-dimethylheptyl)phenol.

[0102] For the purposes of the present invention, the expression halogen-free polycarbonate means a polycarbonate made from a halogen-free bisphenol, a halogen-free chain terminator and optionally a halogen-free branching agent, where a minor amount content of the ppm level of hydrolyzable chlorine (for example due to the production of polycarbonate with phosgene in an interfacial process) is not considered to be "halogen-containing" in the context of the present invention. Polycarbonates of this type with a hydrolyzable chlorine content at the ppm level are halogen-free polycarbonates for the purposes of the present invention.

[0103] Other suitable component A)s which may be mentioned are amorphous polyester carbonates in which phosgene has been replaced in the production process by aromatic dicarboxylic acid units such as isophthalic acid and / or terephthalic acid units. Reference may be made to EP-A 711810 for more details in this regard.

[0104] Other suitable copolycarbonates having a cycloalkyl moiety as a monomer unit are described in EP-A 365 916.

[0105] Furthermore, bisphenol A can be replaced by bisphenol TMC. Polycarbonates of this type are commercially available from Covestro (APEC ).

[0106] Component B

[0107] The molding composition according to the invention comprises, as component B), 0.1 to 30% by weight, preferably 0.5 to 15% by weight, in particular 1 to 10% by weight, very particularly preferably 1 to 5% by weight of poly(ε-caprolactam), based on the total weight of the molding composition.

[0108] Polyesters of this type exhibit the following structure:

[0109]

[0110] where n is from 200 to 600.

[0111] They are generally prepared by ring-opening polymerization of ε-caprolactam ketone.

[0112] These polymers are semi-crystalline and are classified as biodegradable polyesters.

[0113] According to the online encyclopedia, these are polymers that degrade in the presence of microorganisms in a bioactive environment (such as composting, etc.) (as opposed to oxo-degradable polyesters and UV-initiated polyester degradation).

[0114] The average molar mass M of the preferred component B) w is from 5000 to 200 000 g / mol, in particular from 50 000 to 140 000 g / mol (determined by GPC, using hexafluoroisopropanol and 0.05% potassium trifluoroacetate as solvents and PMMA as the standard).

[0115] The melting range (DSC, 20 K / min, according to DIN 11357) is generally from 80 to 150 °C, preferably from 100 to 130 °C.

[0116] Products of this type are commercially available, for example, from Mingevity Corp.

[0117] Component C

[0118] The molding composition according to the invention comprises, as component C), 0.1 to 30% by weight, preferably 0.5 to 15% by weight, in particular 1 to 10% by weight, very particularly preferably 1 to 5% by weight of a biodegradable polyester different from B) and A), based on the total weight of the molding composition.

[0119] The above preference means an aliphatic-aromatic polyester.

[0120] The term aliphatic-aromatic polyester C) means a linear, chain-extended, and preferably branched and chain-extended polyester, as described, for example, in WO96 / 15173 to 15176 or WO 98 / 12242, which is hereby incorporated by reference in its entirety. Mixtures of various semi-aromatic polyesters can also be used. A more recent development of interest is based on renewable raw materials (see WO 2010 / 034689). In particular, the term polyester C) means a product such as (BASF SE).

[0121] Preferred polyesters C) are polyesters containing the following as important components:

[0122] C1) 30 to 70 mol%, preferably 40 to 60 mol%, particularly preferably 50 to 60 mol% of an aliphatic dicarboxylic acid or a mixture thereof, based on components C1) to C2), preferably as follows: adipic acid, azelaic acid, sebacic acid, and brassylic acid,

[0123] C2) 30 to 70 mol%, preferably 40 to 60 mol%, particularly preferably 50 to 60 mol% of an aromatic dicarboxylic acid or a mixture thereof, based on components C1) to C2), preferably as follows: terephthalic acid,

[0124] C3) 98.5 to 100 mol% of 1,4-butanediol and 1,3-propanediol, based on components C1) to C2);

[0125] C4) 0.05 to 1.5 mol%, preferably 0.1 to 0.2 mol% of a chain extender (especially a difunctional or polyfunctional isocyanate, preferably hexamethylene diisocyanate) and an optional branching agent, based on components C1) to C3), preferably: trimethylolpropane, pentaerythritol, especially glycerol.

[0126] The aliphatic diacids and corresponding derivatives C1) that can be preferably used are those having 6 to 20 carbon atoms, preferably 6 to 10 carbon atoms. They can be straight-chain or branched-chain. However, in principle, diacids having a larger number of carbon atoms, for example, having up to 30 carbon atoms, can also be used.

[0127] The following examples may be mentioned: 2-methylglutaric acid, 3-methylglutaric acid, α-ketoglutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, brassylic acid, suberic acid, and itaconic acid. Here, the diacids or their ester-forming derivatives can be used alone, or a mixture of two or more thereof can be used.

[0128] Adipic acid, azelaic acid, sebacic acid, brassylic acid, or their corresponding ester-forming derivatives or mixtures thereof are preferably used. Adipic acid or sebacic acid or their corresponding ester-forming derivatives or mixtures thereof are particularly preferably used.

[0129] Particularly preferred are the following aliphatic-aromatic polyesters: poly(butylene adipate terephthalate) (PBAT), poly(butylene sebacate terephthalate) (PBSeT).

[0130] The aromatic dicarboxylic acid or its ester-forming derivative C2) can preferably be used alone or in the form of a mixture of two or more of them. Particular preference is given to using terephthalic acid or its ester-forming derivative, for example dimethyl terephthalate.

[0131] The diols C3), namely 1,4-butanediol and 1,3-propanediol, can be obtained in the form of recyclable raw materials. Mixtures of the diols mentioned can also be used.

[0132] A branching agent is generally used in an amount of 0.05 to 1.5% by weight, preferably 0.1 to 1.0% by weight, particularly preferably 0.1 to 0.3% by weight, based on the total weight of the polyester C), and / or a chain extender C4) in an amount of 0.05 to 1% by weight, preferably 0.1 to 1.0% by weight, based on the total weight of the polyester C), which is selected from: polyfunctional isocyanates, isocyanurates, oxazolines, carboxylic anhydrides such as maleic anhydride, epoxides (especially epoxy group-containing poly(meth)acrylates), at least trihydric alcohols or at least tricarboxylic acids. Compounds that can be used as the chain extender C4) are polyfunctional, especially bifunctional isocyanates, isocyanurates, oxazolines or epoxides.

[0133] Other compounds that can be considered as branching agents are chain extenders, as well as alcohol or carboxylic acid derivatives having at least three functional groups. Particularly preferred compounds have 3 to 6 functional groups. The following can be mentioned as examples: tartaric acid, citric acid, malic acid, trimesic acid, trimellitic acid, trimellitic anhydride, pyromellitic acid and pyromellitic dianhydride; trimethylolpropane, trimethylolethane; pentaerythritol, polyether triol and glycerol. Polyhydric alcohols are preferred, such as trimethylolpropane, pentaerythritol, especially glycerol. With the aid of the component C4), a biodegradable polyester with pseudoplastic properties can be constructed. The rheology of the melt is improved; easier processing of the biodegradable polyester becomes possible.

[0134] It is generally recommended to add the branching (at least trifunctional) compound at a relatively early stage during the polymerization process.

[0135] Examples of suitable bifunctional chain extenders are toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, diphenylmethane-2,2'-diisocyanate, diphenylmethane-2,4'-diisocyanate, diphenylmethane-4,4'-diisocyanate, naphthalene-1,5-diisocyanate, xylene-diisocyanate, hexamethylene-1,6-diisocyanate, isophorone diisocyanate and methylene bis(4-isocyanatocyclohexane). Particular preference is given to isophorone diisocyanate, especially hexamethylene 1,6-diisocyanate.

[0136] The number-average molar mass (M n ) of the polyester C) is generally from 5,000 to 100,000 g / mol, in particular from 10,000 to 75,000 g / mol, preferably from 15,000 to 38,000 g / mol, while their weight-average molar mass (M w ) is generally from 30,000 to 300,000 g / mol, preferably from 60,000 to 200,000 g / mol, and their M w / M n ratio is from 1 to 6, preferably from 2 to 4. The intrinsic viscosity is preferably from 50 to 450 g / ml, preferably from 80 to 250 g / ml (measured in ortho-dichlorobenzene / phenol (weight ratio 50 / 50) according to ISO 307). The melting point is in the range from 85 to 150 °C, preferably in the range from 95 to 140 °C.

[0137] The MVR (melt volume rate) according to EN ISO 1133-1 DE (190 °C, 2.16 kg weight) is generally from 0.5 to 8 cm 3 / 10 min, preferably from 0.8 to 6 cm 3 / 10 min. The acid value according to DIN EN 12634 is generally from 0.01 mg KOH / g to 1.2 mg KOH / g, preferably from 0.01 mg KOH / g to 1.0 mg KOH / g, particularly preferably from 0.01 mg KOH / g to 0.7 mg KOH / g.

[0138] Component D

[0139] The moulding composition according to the invention comprises 0.1 to 30% by weight, preferably 5 to 25% by weight, in particular 10 to 25% by weight, of hypophosphite, based on the total weight of the moulding composition, as component D).

[0140] Preferably a hypophosphite of formula (I) or / and a diphosphite of formula (II) or a polymer thereof:

[0141]

[0142] wherein

[0143] R 1 and R 2 are the same or different and are hydrogen, or a C1-C6-alkyl in linear or branched form, and / or aryl, or

[0144] R’ is hydrogen, phenyl, tolyl;

[0145] R 3 is a C1-C in linear or branched form 10-alkylene or C6-C 10 -arylene, -alkylarylene or -arylalkylene;

[0146] 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;

[0147] m is from 1 to 4; n is from 1 to 4; x is from 1 to 4.

[0148] Preferably, R of component D) 1 and R 2 are the same or different and are hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl and / or phenyl.

[0149] Preferably, R of component D 3 is methylene, ethylene, n-propylene, isopropylene, n-butylene, tert-butylene, n-pentylene, n-octylene or n-dodecylene, phenylene or naphthylene; methylphenylene, ethylphenylene, tert-butylphenylene, methylnaphthylene, ethylnaphthylene or tert-butylnaphthylene; phenylmethylene, phenylethylene, phenylpropylene or phenylbutylene.

[0150] Particularly preferably, R 1 and R 2 are hydrogen, methyl, ethyl and M = Mg, Ca, Zn, Al, and particularly preferably aluminum hypophosphite and aluminum diethylphosphinate.

[0151] The hypophosphite is preferably prepared by precipitating the corresponding metal salt from an aqueous solution. However, the hypophosphite can also be precipitated in the presence of a suitable inorganic metal oxide or metal sulfide as a carrier material (white pigment, such as TiO2, SnO2, ZnO, ZnS, SiO2). This gives a surface-modified pigment that can be used as a laser-markable flame retardant for thermoplastic polyesters.

[0152] Component E

[0153] The molding composition according to the invention may contain, as component E), from 0 to 20% by weight, preferably from 1 to 20% by weight, in particular from 1 to 15% by weight, of a nitrogen-containing flame retardant, preferably a melamine compound, preferably melamine cyanurate, based on the total weight of the molding composition.

[0154] The melamine cyanurate (component E) preferably suitable for the present invention is preferably the reaction product of equimolar amounts of melamine (formula I) and cyanuric acid or isocyanuric acid (formulas Ia and Ib).

[0155]

[0156]

[0157] It is obtained, for example, by reacting an aqueous solution of the starting compound at 90 to 100 °C. The commercially available product is a white powder with an average d 50 particle size of 1.5 to 7 μm and a d 99 value of less than 50 μm.

[0158] Other suitable compounds (which are usually also referred to as salts or adducts) are melamine sulfate, melamine, melamine borate, melamine oxalate, melamine phosphate prim., melamine phosphate sec., melamine pyrophosphate sec., melamine neopentyl glycol borate, and polymeric melamine phosphate (e.g., CAS No. 56386-64-2 or 218768-84-4).

[0159] Preferably, the melamine polyphosphate is derived from a 1,3,5-triazine compound, where the number n representing the average degree of condensation is from 20 to 200, and the 1,3,5-triazine content per mole of phosphorus atoms is 1.1 to 2.0 mol of 1,3,5-triazine compound, said 1,3,5-triazine compound being selected from melamine, melam, melem, melon, ammeline, ammelide, 2-ureidomethylamine, acetylguanamine, benzoguanamine, and diaminophenyltriazine. Preferably, the n value of these salts is usually from 40 to 150, and the molar ratio of the 1,3,5-triazine compound to the phosphorus atoms is 1.2 to 1.8. Furthermore, the pH of a 10 wt% aqueous slurry of the salt prepared as in EP-A 1 095 030 is usually greater than 4.5, preferably at least 5.0. The pH is usually determined by placing 25 g of the salt and 225 g of pure water in a 300 mL beaker at 25 °C, stirring the resulting aqueous slurry for 30 minutes, and then measuring the pH. The above n value (number average degree of condensation) can be determined by 31P solid state NMR determination. J.R. van Wazer, C.F. Callis, J. Shoolery and R. Jones, J. Am. Chem. Soc., 78, 5715, 1956 disclosed that the number of adjacent phosphate groups is given by a unique chemical shift, which allows a clear distinction between orthophosphates, pyrophosphates and polyphosphates. In addition, EP 1 095 030 A describes a method for preparing polyphosphates of 1,3,5-triazine compounds with an n value of 20 to 200, wherein the 1,3,5-triazine content of the 1,3,5-triazine compound is 1.1 to 2.0 mol of 1,3,5-triazine compound. The method includes converting the 1,3,5-triazine compound into its orthophosphate by orthophosphoric acid, followed by dehydration and heat treatment to convert the orthophosphate into the polyphosphate of the 1,3,5-triazine compound. The heat treatment is preferably carried out at a temperature of at least 300 °C, preferably at least 310 °C. In addition to the orthophosphate of the 1,3,5-triazine compound, other 1,3,5-triazine phosphates can also be used, including, for example, a mixture of orthophosphate and pyrophosphate.

[0160] Suitable guanidine salts are

[0161]

[0162] Compound E) according to the present invention is intended to include not only, for example, benzoguanamine itself and its adducts or salts, but also derivatives substituted on nitrogen and their adducts or salts.

[0163] Other suitable compounds E) are ammonium polyphosphate (NH4PO3) n , where n is about 200 to 1000, preferably 600 to 800, and tris(2-hydroxyethyl)isocyanurate (THEIC) of formula IV

[0164]

[0165] or its reaction product with aromatic carboxylic acid Ar(COOH) m (optionally mixed with each other), where Ar is a mononuclear, binuclear or trinuclear aromatic six-membered ring system, and m is 2, 3 or 4.

[0166] Examples of suitable carboxylic acids are phthalic acid, isophthalic acid, terephthalic acid, 1,3,5-benzenetricarboxylic acid, 1,2,4-benzenetricarboxylic acid, pyromellitic acid, mellitic acid, biphenyltetracarboxylic acid, 1-naphthoic acid, 2-naphthoic acid, naphthalenedicarboxylic acid and anthracene carboxylic acid.

[0167] They are prepared by reacting tris(2-hydroxyethyl)isocyanurate with an acid or its alkyl ester or its halide according to the method in EP-A 584 567.

[0168] Reaction products of this type are mixtures of monomeric esters and low molecular weight polyesters, which may also be crosslinked. The degree of oligomerization is usually from 2 to about 100, preferably from 2 to 20. It is preferred to use mixtures of THEIC and / or its reaction products with phosphorus-nitrogen compounds (especially (NH4PO3) n or melamine pyrophosphate or polymeric melamine phosphate). For example, the mixing ratio of (NH4PO3) n to THEIC is preferably from 90 - 50% by weight:10 - 50% by weight, especially from 80 - 50% by weight:50 - 20% by weight, based on the total amount of the components.

[0169] Other suitable compounds are benzoguanamine compounds of formula V, and especially their adducts with phosphoric acid, boric acid and / or pyrophosphoric acid

[0170]

[0171] wherein R 1 and R 2 are straight-chain or branched-chain alkyl groups having 1 to 10 carbon atoms, preferably hydrogen.

[0172] Also preferred are allantoin compounds of formula VI, and salts thereof with phosphoric acid, boric acid and / or pyrophosphoric acid, and glycoluril of formula VII and salts thereof with the abovementioned acids

[0173]

[0174] wherein R 1 and R 2 are as defined in formula V,

[0175]

[0176] wherein R is as defined in formula V.

[0177] Suitable products are commercially available or can be obtained according to DE-A 196 14 424.

[0178] Cyanoguanidine (formula VIII) which can be used according to the invention is obtained, for example, by reacting calcium cyanamide with carbonic acid, and the resulting cyanamide dimerizes at a pH of 9 to 10 to give cyanoguanidine.

[0179]

[0180] The commercially available product is a white powder with a melting point of 209 °C to 211 °C.

[0181] In the present invention, it is very particularly preferred to use melamine cyanurate having the following particle size distribution:

[0182] d 98≤25 μm, preferably ≤20 μm,

[0183] d 50 <4.5 μm, preferably <3 μm.

[0184] Those skilled in the art generally understand the d 50 value as the particle size value of less than 50% of the particles and greater than 50% of the particles.

[0185] The particle size distribution is usually determined by laser scattering (analogous to ISO 13320).

[0186] Component F

[0187] The molding composition of the present invention may contain 0 to 15% by weight, preferably 0.1 to 15% by weight, especially 0.5 to 10% by weight of an aromatic phosphate having at least one alkyl-substituted benzene ring as component F), based on the total weight of the molding composition.

[0188] The melting point of the preferred aromatic phosphate is preferably 50 to 150 °C, more preferably 60 to 110 °C, measured by DSC according to ISO11357, the first heating curve at 20 K / minute.

[0189] The preferred component F) consists of:

[0190]

[0191] or a mixture thereof, wherein, independently of each other,

[0192] R 1 is H, methyl or isopropyl, preferably H,

[0193] n is 0 to 7, preferably 0,

[0194] R 2 、R 3 、R 4 、R 5 、R 6

[0195] are each independently H, methyl, ethyl or isopropyl, preferably methyl,

[0196] m is 1 to 5, preferably 1 to 2,

[0197] R” is H, methyl, ethyl or cyclopropyl, preferably methyl or hydrogen,

[0198] provided that at least one of R 2 、R 3 、R 4 、R 5 and R 6 moieties is an alkyl moiety.

[0199] Preferably R 6 and R 4 are partially the same, especially R 2 to R 6 are partially the same.

[0200] The preferred component F) is:

[0201]

[0202] These compounds are commercially available from Daihachi as PX- , CAS No. 139189-30-3, or from ICL-IP as Sol- commercially available.

[0203] Component H

[0204] The molding composition according to the invention may comprise, as component H), from 0 to 50% by weight, in particular at most 40% by weight, of other additional substances and processing aids, based on the total weight of the molding composition.

[0205] Additional substances H) that are commonly used are, for example, elastomeric polymers (also commonly referred to as impact modifiers, elastomers or rubbers) in an amount of at most 40% by weight, preferably at most 15% by weight, based on the total weight of the molding composition.

[0206] Very commonly, these are copolymers preferably composed of at least two of the following monomers: ethylene, propylene, butadiene, isobutene, isoprene, chloroprene, vinyl acetate, styrene, acrylonitrile and acrylates or methacrylates having 1 to 18 carbon atoms in the alcohol component.

[0207] Polymers of this type are described, for example, in Houben-Weyl, Methoden der organischen Chemie, Volume 14 / 1, pages 392 to 406 (Georg-Thieme-Verlag, Stuttgart, Germany, 1961), and in the monograph "Toughened Plastics" by C.B. Bucknall (Applied Science Publishers, London, UK, 1977).

[0208] Some preferred types of these elastomers are described below.

[0209] Preferred types of elastomers are those known as ethylene-propylene (EPM) rubbers and ethylene-propylene-diene (EPDM) rubbers.

[0210] EPM rubbers generally have few residual double bonds, while EPDM rubbers can have 1 to 20 double bonds per 100 carbon atoms.

[0211] Examples of diene monomers for EPDM rubbers that may be mentioned are conjugated dienes such as isoprene and butadiene; non-conjugated dienes having 5 to 25 carbon atoms such as 1,4-pentadiene, 1,4-hexadiene, 1,5-hexadiene, 2,5-dimethyl-1,5-hexadiene and 1,4-octadiene; cyclic dienes such as cyclopentadiene, cyclohexadiene, cyclooctadiene and dicyclopentadiene; and alkenyl norbornenes such as 5-ethylidene-2-norbornene, 5-butylidene-2-norbornene, 2-methallyl-5-norbornene and 2-isopropenyl-5-norbornene; and tricyclic dienes such as 3-methyltricyclo[5.2.1.0 2，6 -3,8-decadiene; and mixtures thereof. 1,5-Hexadiene, 5-ethylidene norbornene and dicyclopentadiene are preferred. The diene content of the EPDM rubber is preferably 0.5 to 50% by weight, especially 1 to 8% by weight, based on the total weight of the rubber.

[0212] EPM and EPDM rubbers can also be preferably grafted with reactive carboxylic acids or derivatives of these carboxylic acids. Examples of these are acrylic acid, methacrylic acid and their derivatives such as glycidyl (meth)acrylate, and maleic anhydride.

[0213] Copolymers of ethylene with acrylic acid and / or methacrylic acid and / or with esters of these acids are another group of preferred rubbers. The rubber can also contain dicarboxylic acids such as maleic acid and fumaric acid, or derivatives of these acids such as esters and acid anhydrides, and / or monomers containing epoxy groups. These monomers containing dicarboxylic acid derivatives or containing epoxy groups are preferably incorporated into the rubber by adding monomers containing dicarboxylic acid groups and / or epoxy groups and having the following general formula I, II, III or IV to the monomer mixture:

[0214] R 1 C(COOR 2 )=C(COOR 3 )R 4 (I)

[0215]

[0216] Wherein R 1 to R 9 are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms, m is an integer from 0 to 20, g is an integer from 0 to 10, and p is an integer from 0 to 5.

[0217] Preferably R 1 to R 9Part is hydrogen, where m is 0 or 1 and g is 1. The corresponding compounds can be maleic acid, fumaric acid, maleic anhydride, allyl glycidyl ether, and vinyl glycidyl ether.

[0218] Preferred compounds of formulae I, II and IV are maleic acid, maleic anhydride and (meth)acrylates containing an epoxy group, such as glycidyl acrylate and glycidyl methacrylate, and esters with a tertiary alcohol, such as tert-butyl acrylate. Although the latter do not have a free carboxyl group, they behave similarly to free acids and are therefore called monomers with a potential carboxyl group.

[0219] The copolymer advantageously consists of 50% to 98% by weight of ethylene, 0.1% to 20% by weight of a monomer containing an epoxy group and / or methacrylic acid and / or a monomer containing an anhydride group, and the balance (to make up 100% by weight) being (meth)acrylate.

[0220] Particularly preferred are the following copolymers:

[0221] 50 to 98% by weight, especially 55 to 95% by weight of ethylene,

[0222] 0.1 to 40% by weight, especially 0.3 to 20% by weight of glycidyl acrylate and / or glycidyl methacrylate, (meth)acrylic acid and / or maleic anhydride, and

[0223] 1 to 45% by weight, especially 10 to 40% by weight of n-butyl acrylate and / or 2-ethylhexyl acrylate.

[0224] Other preferred (meth)acrylates are methyl ester, ethyl ester, propyl ester, isobutyl ester and tert-butyl ester.

[0225] Comonomers that can also be used together with these are vinyl esters and vinyl ethers.

[0226] The above ethylene copolymers can be prepared by methods known per se, preferably by random copolymerization under high pressure and elevated temperature. Suitable methods are well known.

[0227] Other preferred elastomers are emulsion polymers, the preparation of which is described, for example, by Blackley in the monograph "Emulsion Polymerization". The emulsifiers and catalysts that can be used are known per se.

[0228] In principle, uniformly structured elastomers or those with a shell structure can be used. The shell-type structure is determined by the order of addition of the individual monomers. The morphology of the polymer is also affected by this order of addition.

[0229] Monomers (by way of example only) for the rubber fraction for preparing elastomers which may be mentioned here are acrylates such as n-butyl acrylate and 2-ethylhexyl acrylate, the corresponding methacrylates, butadiene and isoprene, and mixtures of these. These monomers can be copolymerized with other monomers such as styrene, acrylonitrile, vinyl ethers and with other acrylates or methacrylates such as methyl methacrylate, methyl acrylate, ethyl acrylate or propyl acrylate.

[0230] The soft or rubber phase of the elastomer (having a glass transition temperature below 0 °C) can be the core, the shell or an intermediate shell (in the case where the structure of the elastomer has more than two shells). Elastomers having more than one shell can also have more than one shell consisting of a rubber phase.

[0231] If, in the structure of the elastomer, one or more hard components (glass transition temperature above 20 °C) are involved in addition to the rubber phase, these hard components are generally prepared by polymerizing styrene, acrylonitrile, methacrylonitrile, α-methylstyrene, p-methylstyrene or acrylates or methacrylates such as methyl acrylate, ethyl acrylate or methyl methacrylate as the main monomer. In addition to these, relatively small proportions of other comonomers can also be used here.

[0232] It has proven advantageous in certain cases to use emulsion polymers having reactive groups on the surface. Examples of groups of this type are epoxy groups, carboxyl groups, latent carboxyl groups, amino groups and amide groups, and functional groups which can be introduced by concomitant use of monomers of the following general formula:

[0233]

[0234] where the substituents can be defined as follows:

[0235] R 10 is hydrogen or C1-C4-alkyl,

[0236] R 11 is hydrogen or C1-C5-alkyl or aryl, in particular phenyl,

[0237] R 12 is hydrogen or C1-C 10 alkyl, C6-C 12 aryl or -OR 13 ,,

[0238] R 13 is C1-C5-alkyl or C6-C 12 -aryl, which is optionally substituted by a group containing O or N,

[0239] X is a chemical bond, C1-C 10 alkylene or C6-C12 an arylene group, or

[0240] Y is O-Z or NH-Z, and

[0241] Z is C1-C 10 an alkylene group or C6-C 12 an arylene group.

[0242] The graft monomers described in EP-A 208 187 are also suitable for introducing reactive groups on the surface.

[0243] Other examples that may be mentioned are acrylamide, methacrylamide and substituted acrylates or methacrylates, such as (N-tert-butylamino)ethyl methacrylate, (N,N-dimethylamino)ethyl acrylate, (N,N-dimethylamino)methyl acrylate and (N,N-diethylamino)ethyl acrylate.

[0244] The particles of the rubber phase can also be crosslinked. Examples of crosslinking monomers are 1,3-butadiene, divinylbenzene, diallyl phthalate and dicyclopentadienyl diacrylate, as well as the compounds described in EP-A 50 265.

[0245] Monomers called graft-linking monomers can also be used, i.e., monomers having two or more polymerizable double bonds that react at different rates during polymerization. Compounds of this type are preferably used, in which at least one reactive group polymerizes at approximately the same rate as the other monomers, while the other reactive groups polymerize, for example, significantly more slowly. The different polymerization rates result in a certain proportion of unsaturated double bonds in the rubber. Then if another phase is grafted onto this type of rubber, at least some of the double bonds present in the rubber react with the graft monomer to form chemical bonds, i.e., the phase grafted onto it has at least a certain degree of chemical bonding to the graft matrix.

[0246] Examples of this type of graft-linking monomer are monomers containing allyl groups, especially allyl esters of ethylenically unsaturated carboxylic acids, such as allyl acrylate, allyl methacrylate, diallyl maleate, diallyl fumarate and diallyl itaconate, as well as the corresponding monoallyl compounds of these dicarboxylic acids. In addition to these, there are various other suitable graft-linking monomers. For further details, reference can be made here, for example, to US Patent 4,148,846.

[0247] The proportion of these crosslinking monomers in the impact-modified polymer is generally at most 5% by weight, preferably not more than 3% by weight, based on the impact-modified polymer.

[0248] Some preferred emulsion polymers are listed below. First, mention may be made here of graft polymers having a core and at least one shell and having the following structure:

[0249]

[0250] These graft polymers, in particular ABS polymers and / or ASA polymers, are preferably used for the impact modification of PBT in an amount of at most 40% by weight, optionally in the form of a mixture with at most 40% by weight of polyethylene terephthalate. Blend products of this type can S (formerly from BASF AG S) are commercially available.

[0251] As an alternative to graft polymers having more than one shell in their structure, homogeneous (i.e., single-shell) elastomers composed of 1,3-butadiene, isoprene, and n-butyl acrylate or copolymers thereof can also be used. These products can also be prepared by using crosslinking monomers or monomers having reactive groups simultaneously.

[0252] Examples of preferred emulsion polymers are n-butyl acrylate-(meth)acrylic acid copolymers, n-butyl acrylate-glycidyl acrylate or n-butyl acrylate-glycidyl methacrylate copolymers, graft polymers having a core composed of n-butyl acrylate or based on butadiene and a shell composed of the above copolymers, and copolymers of ethylene with comonomers providing reactive groups.

[0253] The elastomers can also be prepared by other conventional methods, such as by suspension polymerization.

[0254] Silicone rubbers are also preferred, as described in DE-A 37 25 576, EP-A 235 690, DE-A 38 00 603, and EP-A 31 9290.

[0255] Of course, mixtures of the above rubber types can also be used.

[0256] Fibrous or particulate fillers H) that may be mentioned are glass fibers, glass beads, amorphous silica, calcium silicate, calcium metasilicate, magnesium carbonate, kaolin, chalk, mica, barium sulfate, feldspar, and powdered quartz. The amount of fibrous filler H) is usually at most 50% by weight, especially at most 35% by weight, and the amount of particulate filler is at most 30% by weight, especially at most 10% by weight, based on the total weight of the molding composition.

[0257] Preferred fibrous fillers that may be mentioned are aromatic polyamide fibers and potassium titanate fibers, and glass fibers in the form of E glass are particularly preferred here. These can be used in the form of rovings or chopped glass in commercially available forms.

[0258] The amount of the high laser-absorbing filler (e.g., carbon fiber, carbon black, graphite, graphene, or carbon nanotube) is preferably less than 1% by weight, particularly preferably less than 0.05% by weight, based on the total weight of the molding composition.

[0259] To improve the compatibility with the thermoplastic, the fiber filler can be surface-pretreated with a silane compound.

[0260] Suitable silane compounds are those having the following general formula:

[0261] (X-(CH2) n ) k -Si-(O-C m H 2m+1 ) 4-k

[0262] wherein the substituents are defined as follows:

[0263] X

[0264] n is an integer from 2 to 10, preferably from 3 to 4,

[0265] m is an integer from 1 to 5, preferably from 1 to 2,

[0266] k is an integer from 1 to 3, preferably 1.

[0267] Preferred silane compounds are aminopropyltrimethoxysilane, aminobutyltrimethoxysilane, aminopropyltriethoxysilane, aminobutyltriethoxysilane, and the corresponding silanes containing glycidyl as substituent X.

[0268] The usual amount of the silane compound for surface coating is 0.05 to 5% by weight, preferably 0.1 to 1.5% by weight, particularly 0.2 to 0.5% by weight (based on H).

[0269] Needle-shaped mineral fillers are also suitable.

[0270] For the purposes of the present invention, needle-shaped mineral fillers are mineral fillers having strongly elongated needle-like characteristics. An example is acicular wollastonite. The mineral preferably has an L / D (length to diameter) ratio of 8:1 to 35:1, preferably 8:1 to 11:1. Optionally, the mineral filler can be pretreated with the above-mentioned silane compound, but the pretreatment is not necessary.

[0271] The thermoplastic molding composition of the present invention can contain common processing aids as component (H), such as stabilizers, oxidation blockers, agents for counteracting decomposition due to heat and decomposition due to ultraviolet light, lubricants and mold release agents, colorants such as dyes and pigments, plasticizers, etc.

[0272] Examples of oxidation blockers and heat stabilizers that may be mentioned are sterically hindered phenols and / or phosphites, hydroquinones, aromatic secondary amines such as diphenylamine, various substituted members of these groups, and mixtures thereof, in a concentration of up to 1% by weight based on the weight of the thermoplastic molding composition.

[0273] UV stabilizers that may be mentioned and are generally used in an amount of up to 2% by weight based on the molding composition are various substituted resorcinols, salicylates, benzotriazoles, and benzophenones.

[0274] Colorants that may be added are inorganic and organic pigments, and dyes such as aniline black and anthraquinone. For example, EP 1722 984 A, EP 1 353 986 A or DE 10054859 A1 mention particularly suitable colorants.

[0275] Also preferred are esters or amides of saturated or unsaturated aliphatic carboxylic acids having 10 to 40, preferably 16 to 22 carbon atoms with saturated aliphatic alcohols or aliphatic amines having 2 to 40, preferably 2 to 6 carbon atoms.

[0276] The carboxylic acid can be mono- or dibasic. Examples that may be mentioned are pelargonic acid, palmitic acid, lauric acid, margaric acid, dodecanedioic acid, behenic acid, and particularly preferably stearic acid, capric acid, and montanic acid (a mixture of fatty acids having 30 to 40 carbon atoms).

[0277] The aliphatic alcohol can be mono- to tetra-functional. Examples of the alcohol are n-butanol, octanol, stearyl alcohol, ethylene glycol, propylene glycol, neopentyl glycol, and pentaerythritol, preferably glycerol and pentaerythritol.

[0278] The aliphatic amine can be mono-functional to trifunctional. Examples of these are stearylamine, ethylenediamine, propylenediamine, hexamethylenediamine, and bis(6-aminohexyl)amine, with ethylenediamine and hexamethylenediamine being particularly preferred here. The preferred esters or amides are accordingly diglycerol distearate, triglycerol stearate, ethylenediamine distearate, glycerol monopalmate, glycerol trilaurate, glycerol monobehenate, and pentaerythritol tetrastearate.

[0279] Mixtures of various esters or amides can also be used, or esters and amides in any desired mixing ratio.

[0280] Suitable lubricants and mold release agents are, for example, long-chain fatty acids (such as stearic acid or behenic acid), salts thereof (such as calcium stearate or zinc stearate), or montan wax (a mixture of straight-chain saturated carboxylic acids having a chain length of 28 to 32 carbon atoms), calcium montanate or sodium montanate, and low molecular weight polyethylene wax and low molecular weight polypropylene wax.

[0281] Examples of plasticizers are dioctyl phthalate, dibenzyl phthalate, butyl benzyl phthalate, hydrocarbon oils.

[0282] The molding composition according to the invention may also comprise from 0 to 2% by weight of a fluorinated ethylene polymer, based on the total weight of the molding composition. They are polymers of ethylene having a fluorine content of from 55 to 76% by weight, preferably from 70 to 76% by weight, based on the total weight of the fluorinated ethylene polymer.

[0283] Examples of these are polytetrafluoroethylene (PTFE), tetrafluoroethylene - hexafluoropropylene copolymers and tetrafluoroethylene copolymers having a relatively small proportion (usually at most 50% by weight) of copolymerizable ethylenically unsaturated monomers. These are described, for example, by Schildknecht in "Vinyl and Related Polymers", Wiley - Verlag, 1952, pages 484 to 494 and as described by Wall in "Fluoropolymers" (Wiley Interscience, 1972).

[0284] These fluorinated ethylene polymers are homogeneously distributed in the molding composition and preferably have a particle size d 50 (number - average) of from 0.05 to 10 μm, in particular from 0.1 to 5 μm. These small particle sizes can be achieved particularly preferably by using an aqueous dispersion of the fluorinated ethylene polymer and incorporating it into the polyester melt.

[0285] Preparation of the thermoplastic molding composition according to the invention

[0286] The thermoplastic molding composition according to the invention can be prepared by a method known per se by mixing the starting components in a conventional mixing device such as a screw extruder, a Brabender mixer or a Banbury mixer and then extruding them. The extrudate can then be cooled and comminuted. It is also possible to premix the individual components (in a drum or otherwise, premix the individual components into pellets) and then add the remaining starting materials individually and / or in the form of a mixture. The mixing temperature is generally from 230 °C to 290 °C.

[0287] In another preferred mode of operation, the components can be mixed, compounded and granulated with a polyester prepolymer. The resulting pellets are then subjected to solid - state condensation continuously or batchwise under an inert gas at a temperature below the melting point of component A) until the desired viscosity is reached.

[0288] The molding composition according to the invention has good mechanical and flame - retardant properties. The inventors of the present invention have found that the polar - modified polyolefin wax prepared by a metallocene catalyst has a positive effect on the combustion behavior, especially for thin - walled parts. In addition, the processing, especially in extrusion, is improved, i.e., there is no or reduced deposition of additives during processing, especially no or reduced die drool.

[0289] Molded articles produced from the molding composition of the present invention are used for producing internal and external components, which preferably have load-bearing or mechanical functions in the following industries: electrical, furniture, sports, mechanical engineering, hygiene and healthcare, medical, power engineering and drive technology, automotive and other means of transportation, or as housing materials for telecommunications equipment and devices, consumer electronics, household appliances, mechanical engineering, heating industry, or as fastening components for installation work, or for any type of container and ventilation components.

[0290] These materials are suitable for producing any type of fiber, foil and molded article, especially for the following applications: plugs, switches, housing components, housing covers, headlight bezels, showerheads, fittings, smooth irons, rotary switches, stove controllers, frying pan lids, door handles, (rear) mirror housings, (tailgate) screen wipers, sheaths for optical conductors, loose buffer tubes for monofilaments for braided sleeve FOC (fiber optic cable) applications and monofilaments for braided sleeves.

[0291] Accordingly, the present invention further relates to a method for producing fibers, films and molded articles, which comprises using the polyester molding composition according to the present invention, and to fibers, films or molded articles obtained from the polyester molding composition according to the present invention.

[0292] Preferably, the thermoplastic molding composition is a thin-walled component, preferably with a wall thickness of at most 0.4 mm. Preferred thin-walled components are selected from the fibers, foils and molded articles as described above.

[0293] Devices that can be produced from the polyester of the present invention in the electrical and electronic fields are: plugs, plug components, plug connectors, cable harness assemblies, circuit mountings, circuit mounting assemblies, three-dimensional injection molded circuit mountings, electrical connector elements, electromechanical assemblies and optoelectronic assemblies.

[0294] Uses inside the vehicle are for instrument panels, steering column switches, seat components, headrests, center consoles, gearbox components and door modules, and possible uses outside the vehicle are for door handles, headlight components, external mirror components, windshield wiper components, windshield wiper protectors, decorative grilles, roof rails, sunroof frames and external body components.

[0295] Possible uses of the polyester in the kitchen and household fields are: for the production of components for kitchen equipment, such as deep fryers, ironing machines, buttons; and also for applications in the garden and leisure fields, such as for components of irrigation systems or garden equipment.

[0296] The present invention also relates to the use of polyolefin waxes prepared by metallocene catalysts for improving the flame retardancy of thermoplastic molding compositions comprising thermoplastic polyesters, wherein the polyolefin wax is a homopolymer of ethylene, a copolymer of ethylene with one or more 1-olefins which may be linear or branched, substituted or unsubstituted and having 3 to 18 carbon atoms, or a homopolymer of propylene, which is polar modified by reacting the polyolefin wax with an α,β-unsaturated carboxylic acid or a derivative thereof. Suitable polyolefin waxes, suitable thermoplastic polyesters and suitable thermoplastic molding compositions are as described above.

[0297] The invention is further illustrated by the following examples. Examples

[0298] Preparation of the components of the molding composition / molding composition / specimens

[0299] Component A:

[0300] Polybutylene terephthalate having an intrinsic viscosity IV of 130 mL / g and a carboxyl end group content of 34 meq / kg (B 4520 from BASF SE) (IV measured according to DIN 53728 and ISO 1628 at 25 °C in a 0.5 wt% solution of phenol / o-dichlorobenzene 1:1 mixture).

[0301] Component B:

[0302] Poly-(ε)-caprolactone (6500 from Ingevity Corp.) 6500): M w (GPC, hexafluoroisopropanol / 0.05% potassium trifluoroacetate, PMMA standard): 99 300 g / mol, intrinsic viscosity IV 226 mL / g (IV measured according to DIN 53728 and ISO 1628 at 25 °C in a 0.5 wt% solution of phenol / o-dichlorobenzene 1:1 mixture). Melting range (DSC, 20 K / min, according to DIN 11357): 58 to 60 °C.

[0303] Component C:

[0304] Copolyester: polyadipic acid-co-butylene terephthalate, melting point (DSC, 20 K / min, according to DIN11357): 100 °C to 120 °C. F blend C1200 from BASF SE F blend C1200.

[0305] Component D / 1:

[0306] Aluminum diethylphosphinate (OP 1230 from Clariant GmbH) OP 1230).

[0307] Component F / 1:

[0308] Aromatic phosphate ester. Melting range (DSC, 20 K / min, according to DIN 11357): 92 to 100 °C.

[0309] PX-200 from Daihachi Chemical Industry Co.

[0310]

[0311] Component F / 2:

[0312] Aromatic phosphate ester. Melting range (DSC, 20 K / min, according to DIN 11357): 102 to 110 °C. From ICL-IP Europe's SOL-DP.

[0313]

[0314] Component H / 1:

[0315] PTFE powder. Dyneon TF2071 PPFE from 3M of Dyneon GmbH. TDS particle size is 500 μm (ISO12086) and density is 2.16 g / cm 3 (ISO 12086).

[0316] Component G:

[0317] Maleic anhydride grafted metallocene polyethylene wax. From Clariant GmbH's PE MA 4221 fine granules.

[0318] Component H / 2:

[0319] Stabilizer. From BASF SE's 168.

[0320] Preparation of the molding composition

[0321] The molding compositions for the inventive examples and comparative examples in Table 1 were prepared by a ZE25 twin-screw extruder. The temperature profile was kept constant, increasing from 240 °C in zone 1 to 260 °C (zones 2 to 9). The rotational speed was set at 130 rpm, and the throughput was about 7.5 to 9.6 kg / h, depending on the formulation. The extrudate was pulled into a water bath and pelletized. The pellets were then processed by injection molding.

[0322] Performance testing

[0323] The test specimens listed in Table 1 were injection-molded in an Arburg 420C injection molding machine at a melt temperature of approximately 270 °C and a mold temperature of approximately 80 °C. Test specimens for stress testing were prepared according to ISO 5272: / 1993, and test specimens for impact resistance testing were prepared according to ISO 179-2 / 1eA.

[0324] The MVR test was carried out according to ISO 1133.

[0325] First, the flame retardancy of the molded composition was determined by the UL 94V method (Underwriters Laboratories Inc. Standard of Safety, "Test for Flammability of Plastic Materials for Parts in Devices and Appliances", pages 14 to 18, Northbrook 1998).

[0326] The glow-wire flammability index (GWFI) was tested on the sheet according to DIN EN 60695-2-12. The GWFI test is a general applicability test for plastics in contact with live parts. The temperature determined is the highest temperature that meets one of the following conditions in three consecutive tests: (a) the sample does not catch fire, or (b) the flame extinction time or afterglow extinction time within 30 seconds after exposure to the glow wire, and the underlying padding does not catch fire.

[0327] The sum of the contents of components A) to H) in Table 1 (comparative examples = V1 to V4, inventive examples = E1) adds up to 100% by weight. The composition and measurement results of the molded articles are summarized in Table 1:

[0328] Table 1

[0329] Component (wt%) / Test method V1 V2 V3 V4 E1 A 69.3 68.3 67.3 66.3 69.3 B 4 4 4 4 4 C 4 4 4 4 4 D / 1 20 21 22 23 20 F / 1 1 1 1 1 1 F / 2 1 1 1 1 1 H / 1 0.4 0.4 0.4 0.4 0.4 G - - - - 0.1 H / 2 0.3 0.3 0.3 0.3 0.3 <![CDATA[VZ 1 ) / [mL / g]]]> 125 126 125 125 126 <![CDATA[MVR 2 )275 / 2.16 / [ccm / 10min]]]> 31.9 30.9 28.8 28.9 33.0 Tensile modulus of elasticity / [MPa] 2069 2079 2094 2100 2082 Tensile strength at break / [MPa] 27.9 27.3 26.8 26.0 28.0 Tensile strain at break / [%] 22.5 20.1 19.5 18.1 21.2 <![CDATA[Charpy V-notch / KJ / m 2 > 38 34 35 32 34 <![CDATA[Charpy V-notch impact energy at -30 °C / KJ / m 2 > 32 33 31 28 32 <![CDATA[Charpy impact / KJ / m 2 > 3.2 2.9 3.0 2.7 3.2 UL94 (0.4mm) V-2 V-2 V-2 V-2 V-0 UL94 (0.8mm) V-0 V-0 V-0 V-0 V-0 GWFI 960°C / 0.75mm Pass Pass Pass Pass Pass GWIT 775°C / 0.75mm Pass Pass Pass Pass Pass GWFI 960°C / 1.5mm Pass Pass Pass Pass Pass Deposition at the nozzle during pipe extrusion Severe Severe Severe Severe None

[0330] 1) Viscosity number according to ISO307

[0331] 2) Melt viscosity rate according to ISO1133

[0332] From the data in Table 1, it can be seen that the polyester molding composition E1 of the present invention shows improved fire resistance, especially for thin-walled parts (UL94 test at 0.4 mm). The amount of component G used has a greater impact on the UL94 combustion behavior than the increase in flame retardant D / 1 (V2 to V4). In addition, the molding composition of the present invention shows significantly improved processing behavior (no deposition at the nozzle) in extrusion applications.

Claims

1. A thermoplastic molding composition comprising A) 10 to 99.6% by weight of a thermoplastic polyester different from C); B) 0.1 to 30% by weight of poly(ε-caprolactone); C) 0.1 to 30% by weight of a biodegradable polyester different from B); D) 0.1 to 30% by weight of a phosphinate; E) 0 to 20% by weight of a nitrogen-containing flame retardant; F) 0 to 15% by weight of an aromatic phosphate having at least one alkyl-substituted benzene ring; G) 0.05 to 1% by weight of a polyolefin wax prepared by a metallocene catalyst, wherein the polyolefin wax is a homopolymer of ethylene, a copolymer of ethylene and one or more linear or branched, substituted or unsubstituted 1-olefins having 3 to 18 carbon atoms, or a homopolymer of propylene, which is polar-modified by reacting the polyolefin wax with an α,β-unsaturated carboxylic acid or its derivative; H) 0 to 50% by weight of other additional substances, wherein the sum of the weight percentages of components A) to H) is 100%; wherein the α,β-unsaturated carboxylic acid or its derivative is acrylic acid or methacrylic acid or its ester or amide, maleic acid, maleic anhydride, monoester of maleic acid, diester of maleic acid, amide of maleic acid, maleimide or N-alkyl-substituted maleimide.

2. A thermoplastic molding composition comprising A) 10 to 99.6% by weight of a thermoplastic polyester different from C); B) 0.1 to 30% by weight of poly(ε-caprolactone); C) 0.1 to 30% by weight of a biodegradable polyester different from B); D) 0.1 to 30% by weight of a phosphinate of formula (I) and / or a bisphosphinate of formula (II) or a polymer thereof; E) 0 to 20% by weight of a nitrogen-containing flame retardant; F) 0 to 15% by weight of an aromatic phosphate having at least one alkyl-substituted benzene ring; G) 0.05 to 1% by weight of a polyolefin wax prepared by a metallocene catalyst, wherein the polyolefin wax is a homopolymer of ethylene, a copolymer of ethylene and one or more linear or branched, substituted or unsubstituted 1-olefins having 3 to 18 carbon atoms, or a homopolymer of propylene, which is polar-modified by reacting the polyolefin wax with an α,β-unsaturated carboxylic acid or its derivative; H) 0 to 50% by weight of other additional substances, wherein the sum of the weight percentages of components A) to H) is 100%; wherein the α,β-unsaturated carboxylic acid or its derivative is acrylic acid or methacrylic acid or its ester or amide, maleic acid, maleic anhydride, monoester of maleic acid, diester of maleic acid, amide of maleic acid, maleimide or N-alkyl-substituted maleimide; and / or wherein R 1 and R 2 which is the same as or different from R, is hydrogen, or a C1-C6-alkyl in straight-chain or branched-chain form, and / or aryl, or wherein R' is hydrogen, phenyl or tolyl; R 3 is a C1-C in linear or branched form 10 -alkylene or C6-C 10 -arylene, C1-C 10 -alkyl-C6-C 10 arylene or C6-C 10 -arylC1-C 10 alkylene; 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; x is 1 to 4.

3. Thermoplastic molding composition according to claim 2, wherein R of component D) 1 and R 2 are, independently of one another, hydrogen, methyl or ethyl.

4. The thermoplastic molding composition according to claim 1 or 2, wherein the monoester of maleic acid is a monoalkyl maleate.

5. The thermoplastic molding composition according to claim 1 or 2, wherein the diester of maleic acid is a dialkyl maleate.

6. The thermoplastic molding composition according to claim 1 or 2, wherein component (G) is a homopolymer of ethylene or a copolymer of ethylene and one or more linear or branched, substituted or unsubstituted 1-olefins having 3 to 18 carbon atoms, which is polar-modified by reacting the polyolefin wax with maleic anhydride.

7. The thermoplastic molding composition according to claim 1 or 2, wherein the thermoplastic polyester (A) is based on aromatic dicarboxylic acids and aliphatic and / or aromatic dihydroxy compounds.

8. The thermoplastic molding composition according to claim 7, wherein the thermoplastic polyester (A) is polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate or a mixture thereof.

9. The thermoplastic molding composition according to claim 8, wherein the polyethylene terephthalate and / or polybutylene terephthalate contains at most 1% by weight of 1,6-hexanediol and / or 2-methyl-1,5-pentanediol as other monomer units.

10. The thermoplastic molding composition according to claim 9, wherein the polyethylene terephthalate and / or polybutylene terephthalate contains at most 0.75% by weight of 1,6-hexanediol and / or 2-methyl-1,5-pentanediol as other monomer units.

11. The thermoplastic molding composition according to claim 1 or 2, wherein the biodegradable polyester of component (C) consists of: C1) 30 to 70 mol% of aliphatic dicarboxylic acids or a mixture thereof, based on C1) and C2); C2) 30 to 70 mol% of aromatic dicarboxylic acids or a mixture thereof, based on C1) and C2); C3) 98.5 to 100 mol% of 1,4-butanediol or 1,3-propanediol or a mixture thereof, based on C1) and C2); C4) 0.05 to 1.5% by weight of a chain extender, based on C1) to C3).

12. The thermoplastic molding composition according to claim 11, wherein the biodegradable polyester of component (C) is poly(butylene adipate terephthalate) (PBAT) or poly(butylene sebacate terephthalate) (PBSeT).

13. The thermoplastic molding composition according to claim 1 or 2, wherein component (E) is a reaction product of melamine (Formula I) with cyanuric acid (Formula Ia) or isocyanuric acid (Formula Ib).

14. The thermoplastic molding composition according to claim 1 or 2, wherein the melting point of component (F) measured by DSC at a first heating rate of 20 K / min according to ISO 11357 is 50 °C to 150 °C.

15. The thermoplastic molding composition according to claim 1 or 2, wherein component (F) consists of: or a mixture thereof, wherein, independently of each other, R 1 is H, methyl or isopropyl n is 0 to 7 R 2 、R 3 、R 4 、R 5 、R 6 each independently represents H, methyl, ethyl or isopropyl m is 1 to 5 R” is H, methyl, ethyl or cyclopropyl, The condition is that at least one of R 2 , R 3 , R 4 , R 5 or R 6 moieties is an alkyl moiety.

16. The thermoplastic molding composition according to claim 15, wherein the substituents of Formulas III, IV and V are: R 1 hydrogen and / or R 2 、R 3 、R 4 、R 5 and R 6 methyl and / or m is 1 or 2.

17. The thermoplastic molding composition according to claim 16, wherein component F) consists of:

18. A method for producing a fiber, film or molded article, comprising using the thermoplastic molding composition according to any one of claims 1 to 17.

19. A fiber, film or molded article obtained from the thermoplastic molding composition according to any one of claims 1 to 17.

20. Use of a polyolefin wax prepared by a metallocene catalyst for improving the flame retardancy of a thermoplastic molding composition comprising a thermoplastic polyester according to any one of claims 1 to 17, wherein the polyolefin wax is a homopolymer of ethylene, a copolymer of ethylene with one or more linear or branched, substituted or unsubstituted 1-olefins having 3 to 18 carbon atoms, or a homopolymer of propylene, which is polar-modified by reacting the polyolefin wax with an α,β-unsaturated carboxylic acid or a derivative thereof; wherein the α,β-unsaturated carboxylic acid or a derivative thereof is acrylic acid or methacrylic acid or an ester or amide thereof, maleic acid, maleic anhydride, a monoester of maleic acid, a diester of maleic acid, an amide of maleic acid, maleimide or an N-alkyl-substituted maleimide.

21. The use according to claim 20, wherein the thermoplastic molding composition is a thin-walled part having a wall thickness of at most 0.4 mm.

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