Polycarbonate compositions having a high cti

Abstract

Described are thermoplastic compositions on the basis of aromatic polycarbonate having a high comparative tracking index, good flame retardancy and a high heat deflection temperature. The compositions contain a combination of polyalkyl(meth)acrylate, phosphorus-containing flame retardant and fluorine-containing anti-dripping agent.

Description

[0001] Polycarbonate compositions with high CTI

[0002] The invention relates to flame-retardant thermoplastic compositions based on polycarbonate with high tracking resistance.

[0003] Polycarbonate offers many advantages over other thermoplastic polymers due to its high impact strength, high heat resistance, and a certain inherent flame retardancy. This unique property profile makes polycarbonate compositions suitable for a wide variety of applications, for example, in the field of electrical and electronic components. Good insulating properties and high flame retardancy are particularly important safety-related basic requirements for materials used in this field. In applications where the plastic is in direct contact with the electrical conductors, high resistance to leakage currents under voltage load is required to prevent short circuits and thus fire within the component.

[0004] Comparative tracking index (CTI) generally describes the resistance of a plastic material to environmental influences. The CTI value is a measure of a plastic's tendency to form electrically conductive paths on its surface when exposed to environmental influences such as moisture and contamination, and to promote resulting electrical leakage currents. The higher the tracking resistance or tracking resistance (CTI value) of a material, the better suited it is for use in high-voltage applications, e.g. in today's electromobility applications. A further advantage of materials with a high CTI value is the possibility of electrical conductor paths in an electronic component being located closer together without the risk of a short circuit. This in turn enables the reduction of component dimensions and thus more compact designs and weight savings.

[0005] In contrast to other thermoplastic polymers such as polystyrene, polyester, etc., polycarbonate itself has very low tracking resistance and moderate flame retardancy. Due to the high proportion of aromatic structures, polycarbonate has a relatively high tendency to carbonize. The CTI of pure polycarbonate is approximately 250 V or even lower (F. Acquasanta et al., Polymer Degradation and Stability, 96 (2011), 2098-2103). However, for numerous applications in the electrical / electrical (EE) sector, e.g., in the field of electromobility, a high CTI, typically of 600 V (corresponding to insulating material group PLC 0 according to EN 50124), is required for the materials used for safety reasons. At the same time, the materials must exhibit high flame retardancy, i.e., a VO classification according to UL 94V, especially for thin wall thicknesses.Pure polycarbonate typically already possesses a certain degree of intrinsic flame retardancy (V2 classification according to UL 94 V), but this is insufficient for most applications in the renewable energy sector. To achieve the required VO classification according to UL94V, the addition of suitable flame retardants is necessary. Typically, halogenated sulfonates (e.g., Rimar salt (potassium perfluorobutanesulfonate, C4 salt) or KSS salt (potassium diphenylsulfone-3-sulfonate)) or organic phosphates (e.g., bisphenol A bis(diphenyl phosphate) (BDP), resorcinol bis(diphenyl phosphate) (RDP)) or phosphazenes are used for polycarbonate. The mechanism of action of these flame retardants is based on the formation of a solid, charred surface layer that interrupts the oxygen supply and thus inhibits the combustion process.

[0006] The underlying effect for good tracking resistance is, among other things, a low tendency to form conductive pathways on the surface. This is in direct contrast to the "charring" mechanism of action of surface-active flame retardants and thus presents a particular challenge in balancing CTI and flame retardancy.

[0007] The object was therefore to provide polycarbonate-based compositions that achieve a UL94 VO classification at 2 mm, particularly preferably at 1.5 mm (after conditioning for 7 days at 20% relative humidity and 70°C ambient temperature) as well as a high CTI of at least 375 V, preferably at least 400 V, most preferably 600 V or more, preferably determined according to the rapid test method based on IEC 60112:2009. Due to the area of ​​application and the heat development in EE components, the compositions should preferably also have good heat resistance, in particular a Vicat softening temperature, determined according to ISO 306:2014-3, VST Method B, of at least 105 °C, particularly preferably at least 110 °C ± 2 °C. In addition, the CTI should preferably be robust, i.e.The high CTI should be reliably achieved at different operating voltages, not only at 600 V, but also at 300 V or 350 V.

[0008] Surprisingly, it has been shown that this property profile can be achieved by special combinations of aromatic polycarbonate with polyalkyl (meth)acrylate in combination with phosphorus-containing flame retardant and with fluorine-containing anti-drip agent.

[0009] The invention therefore relates to a thermoplastic composition consisting of

[0010] A) at least 70% by weight of aromatic polycarbonate,

[0011] B) 4 wt% to 25 wt% polyalkyl(meth)acrylate,

[0012] C) 1.5 wt% to 10 wt% phosphorus-containing flame retardant,

[0013] D) 0.3 wt.% to 2 wt.% of fluorine-containing anti-drip agent, E) optionally one or more further additives, preferably with one or more further additives selected from the group consisting of one or more mold release agents, heat stabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers, impact modifiers, optical brighteners, hydrolysis stabilizers, compatibilizers, additives for laser marking and mixtures thereof, wherein the wt.% data relate to the total composition and wherein the ratio of the amount of polyalkyl (meth)acrylate in wt.% and the amount of phosphorus-containing flame retardant in wt.% is < 10.

[0014] It is understood that all components contained in the composition according to the invention together amount to 100% by weight. Where the upper limit for a numerical range is specified as "up to X," this includes the stated numerical value with its rounded upper range.

[0015] It is understood that the components used may contain common impurities, for example, resulting from their manufacturing processes. It is preferable to use components that are as pure as possible. It is further understood that these impurities may also be present in a closed formulation of the composition.

[0016] The invention also relates to molded parts produced from the thermoplastic compositions according to the invention, i.e., molded parts consisting of a thermoplastic composition according to the invention or comprising a region of a thermoplastic composition according to the invention. Such molded parts are, in particular, those for which the aforementioned property profile is particularly attractive, i.e., molded parts that are parts of components from the renewable energy sector, in particular high-voltage switches, inverters, relays, electronic connectors, electrical connectors, circuit breakers, components for photovoltaic applications, electric motors, heat sinks, chargers and plugs for electric vehicles, electrical junction boxes, smart meter housings, miniature circuit breakers, and busbars. The component is preferably designed for an operating voltage of at least 400 V.For this purpose, the material advantageously used preferably has a tracking resistance of at least 600 V, determined as described above using the rapid test method based on IEC 60112:2009.

[0017] The compositions according to the invention exhibit no significant leakage current (> 0.5 A over 2 s) upon application of at least 50 drops of a 0.1% ammonium chloride solution at 375 V, more preferably at 400 V, and particularly preferably at 600 V, wherein the test is preferably carried out according to the rapid test method described in the description section based on IEC 60112:2009. At the same time, the compositions according to the invention have a flame retardancy of V0 according to UL 94 V for test specimen thicknesses of 2 mm, even more preferably also of at least VI, particularly preferably V0, at 1.5 mm, in each case after conditioning the test specimens for 7 days at 20% relative humidity and an ambient temperature of 70°C.In addition to the high CTI and good flame retardancy, the compositions preferably also have good heat resistance, which is demonstrated by a Vicat softening temperature, determined according to ISO 306:2014-3, VST Method B, of at least 105°C, more preferably at least 110°C ± 2°C.

[0018] The invention therefore also relates to the use of 4% by weight to 25% by weight, preferably 5% by weight to 20% by weight of polyalkyl (meth)acrylate, 1.5% by weight to 10% by weight, preferably 2% by weight to 8% by weight of phosphorus-containing flame retardant and 0.3 to 2% by weight of fluorine-containing anti-drip agent, where the wt% data relate to the resulting total composition, to achieve a high CTI of 375 V, more preferably 400 V, particularly preferably 600 V and a UL94 VO classification with a test specimen thickness of 2 mm, more preferably also of at least VI, particularly preferably V0 at 1.5 mm, in particular after conditioning the test specimens for 7 days at 20% relative humidity and 70°C ambient temperature, in a thermoplastic composition containing at least 70% by weight of aromatic polycarbonate.

[0019] The features mentioned as preferred, particularly preferred, etc. for the composition naturally also apply with regard to the use according to the invention.

[0020] The individual components of the compositions according to the invention are explained in more detail below:

[0021] Component A

[0022] Component A of the compositions according to the invention are aromatic polycarbonates.

[0023] Aromatic polycarbonates within the meaning of the present invention include both homopolycarbonates and copolycarbonates and / or polyestercarbonates; the polycarbonates can be linear or branched in a known manner. Mixtures of polycarbonates can also be used according to the invention.

[0024] The thermoplastic polycarbonates, including the thermoplastic aromatic polyester carbonates, preferably have weight-average molecular weights M wfrom 15,000 g / mol to 40,000 g / mol, more preferably up to 34,000 g / mol, particularly preferably from 17,000 g / mol to 33,000 g / mol, in particular from 19,000 g / mol to 32,000 g / mol, determined by gel permeation chromatography, calibrated against bisphenol A polycarbonate standards using dichloromethane as the eluent, calibration with linear polycarbonates (from bisphenol A and phosgene) of known molar mass distribution from PSS Polymer Standards Service GmbH, Germany, calibration according to method 2301-0257502-09D (from 2009 in German) from Currenta GmbH & Co. OHG, Leverkusen. The eluent is dichloromethane. Column combination of cross-linked styrene-divinylbenzene resins. Diameter of the analytical columns: 7.5 mm; Length: 300 mm. Column material particle size: 3 pm to 20 pm. Solution concentration: 0.2 wt.%. Flow rate: 1.0 ml / min. Solution temperature: 30°C. Use of UV and / or RI detection.

[0025] The melt volume flow rate MVR of the aromatic polycarbonate used, determined according to ISO 1133:2012-03, at a test temperature of 300°C and a load of 1.2 kg, is preferably 5 to 35 cm 3 / (10 min), more preferably 6 cm 3 / (10 min) up to 25 cm 3 / (10 min), even more preferably 6 to 21 cm 3 / ( 10 min).

[0026] A portion, up to 80 mol%, preferably from 20 mol% to 50 mol%, of the carbonate groups in the polycarbonates used according to the invention can be replaced by aromatic dicarboxylic acid ester groups. Such polycarbonates, which contain both carbonic acid residues and acid residues of aromatic dicarboxylic acids incorporated into the molecular chain, are referred to as aromatic polyester carbonates. For the purposes of the present invention, they are subsumed under the generic term of thermoplastic aromatic polycarbonates.

[0027] Details of the production of polycarbonates have been documented in numerous patents published over the past 40 years. Examples include Schnell, "Chemistry and Physics of Polycarbonates," Polymer Reviews, Volume 9, Interscience Publishers, New York, London, Sydney 1964; D. Freitag, U. Grigo, PR Müller, H. Nouvertne, BAYER AG, "Polycarbonates" in Encyclopedia of Polymer Science and Engineering, Volume 11, Second Edition, 1988, pages 648-718; and finally, U. Grigo, K. Kirchner, and PR Müller, "Polycarbonates" in Becker / Braun, Kunststoff-Handbuch, Volume 3 / 1, Polycarbonates, Polyacetals, Polyesters, Cellulose Esters, Carl Hanser Verlag Munich, Vienna 1992, pages 117 to 299.

[0028] Aromatic polycarbonates are produced, for example, by reacting dihydroxyaryl compounds with carbonic acid halides, preferably phosgene, and / or with aromatic dicarboxylic acid dihalides, preferably benzenedicarboxylic acid dihalides, by the interfacial process, optionally using chain terminators and optionally using trifunctional or more than trifunctional branching agents. Production via a melt polymerization process by reacting dihydroxyaryl compounds with, for example, diphenyl carbonate is also possible. To produce the polyester carbonates, some of the carbonic acid derivatives are replaced by aromatic dicarboxylic acids or derivatives of dicarboxylic acids, depending on the carbonate structural units to be replaced in the aromatic polycarbonates by aromatic dicarboxylic acid ester structural units.

[0029] Dihydroxyaryl compounds suitable for the production of polycarbonates are those of the formula (1)

[0030] HO-Z-OH (1), in which

[0031] Z is an aromatic radical having 6 to 30 C atoms, which may contain one or more aromatic nuclei, may be substituted and may contain aliphatic or cycloaliphatic radicals or alkylaryls or heteroatoms as bridge members.

[0032] Preferably, Z in formula (1) represents a radical of formula (2) in the

[0033] R 6 and R 7 independently of one another represent H, C 1 -C 16 -alkyl, C 1 -C 16 -alkoxy, halogen such as Cl or Br, or each optionally substituted aryl or aralkyl, preferably H or C 1 -C 12 -alkyl, particularly preferably H or C 1 -C 12 -alkyl and very particularly preferably H or methyl, and

[0034] X represents a single bond, -SO2-, -CO-, -O-, -S-, Ci- to C (, -alkylene. C2- to C5-

[0035] Alkylidene or C5- to C6-cycloalkylidene, which may be substituted by C1- to C12-alkyl, preferably methyl or ethyl, and furthermore represents C1- to C12-arylene, which may optionally be condensed with further aromatic rings containing heteroatoms.

[0036] Preferably, X represents a single bond, C - to C5-alkylene, C - to C5-alkylidene, C - to C - cycloalkylidene, -O-, -SO-, -CO-, -S-, -SO2- or a radical of the formula (3)

[0037] Examples of dihydroxyaryl compounds are: dihydroxybenzenes, dihydroxydiphenyls, bis-(hydroxyphenyl)-alkanes, bis-(hydroxyphenyl)-cycloalkanes, bis-(hydroxyphenyl)-aryls, bis-(hydroxyphenyl)-ethers, bis-(hydroxyphenyl)-ketones, bis-(hydroxyphenyl)-sulfides, bis-(hydroxyphenyl)-sulfones, bis-(hydroxyphenyl)-sulfoxides, 1,1'-bis-(hydroxyphenyl)-diisopropylbenzenes and their nuclear alkylated and nuclear halogenated compounds.

[0038] Dihydroxyaryl compounds suitable for the production of polycarbonates are, for example, hydroquinone, resorcinol, dihydroxydiphenyls, bis-(hydroxyphenyl)-alkanes, bis-(hydroxyphenyl)-cycloalkanes, bis-(hydroxyphenyl)-sulfides, bis-(hydroxyphenyl)-ethers, bis-(hydroxyphenyl)-ketones, bis-(hydroxyphenyl)-sulfones, bis-(hydroxyphenyl)-sulfoxides, a-a'-bis-(hydroxyphenyl)-diisopropylbenzenes, phthalimidines derived from isatin or phenolphthalein derivatives, as well as their core-alkylated, core-arylated and core-halogenated compounds.

[0039] Preferred dihydroxyaryl compounds are 4,4'-dihydroxydiphenyl, 2,2-bis-(4-hydroxyphenyl)-propane (bisphenol A), 2,4-bis-(4-hydroxyphenyl)-2-methylbutane, 1,1-bis-(4-hydroxyphenyl)-p-diisopropylbenzene, 2,2-bis-(3-methyl-4-hydroxyphenyl)-propane, dimethyl bisphenol A, bis-(3,5-dimethyl-4-hydroxyphenyl)-methane, 2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)-propane, bis-(3,5-dimethyl-4-hydroxyphenyl)-sulfone, 2,4-bis-(3,5-dimethyl-4-hydroxyphenyl)-2-methylbutane, 1,1- Bis-(3,5-dimethyl-4-hydroxyphenyl)-p-diisopropylbenzene and 1, l-Bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, as well as dihydroxyaryl compounds (I) to (III) in which R' is in each case a C 1 -C 4 alkyl radical, aralkyl radical or aryl radical, preferably a methyl radical or phenyl radical, most preferably a methyl radical.

[0040] Particularly preferred dihydroxyaryl compounds are 2,2-bis-(4-hydroxyphenyl)-propane (bisphenol A), 2,2-bis-(3,5-dimethyl-4-hydroxyphenyl)-propane, l,l-bis-(4-hydroxyphenyl)-cyclohexane, l,l-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 4,4'-dihydroxydiphenyl and dimethyl-bisphenol A as well as the bisphenols of the formulas (I), (II) and (III).

[0041] These and other suitable dihydroxyaryl compounds are described, for example, in US 2 999 835 A, US 3 148 172 A, US 2 991 273 A, US 3 271 367 A, US 4 982 014 A and US 2 999 846 A, in DE 1 570 703 A, DE 2 063 050 A, DE 2 036 052 A, DE 2 211 956 A and DE 3 832 396 A, in FR 1 561 518 A, in the monograph "H. Schnell, Chemistry and Physics of Polycarbonates, Interscience Publishers, New York 1964" and in JP 62039 / 1986 A, JP 62040 / 1986 A and JP 105550 / 1986 A.

[0042] In the case of homopolycarbonates, only one dihydroxyaryl compound is used; in the case of copolycarbonates, two or more dihydroxyaryl compounds are used.

[0043] Suitable carbonic acid derivatives include phosgene or diphenyl carbonate.

[0044] Suitable chain terminators that can be used in the production of polycarbonates are monophenols. Examples of suitable monophenols include phenol itself, alkylphenols such as cresols, p-tert-butylphenol, cumylphenol, and mixtures thereof.

[0045] Preferred chain terminators are phenols that are mono- or polysubstituted by C1- to C30-alkyl radicals, linear or branched, preferably unsubstituted, or by tert-butyl. Particularly preferred chain terminators are phenol, cumylphenol, and / or p-tert-butylphenol.

[0046] The amount of chain terminator to be used is preferably 0.1 to 5 mol%, based on the moles of dihydroxyaryl compounds used. The chain terminators can be added before, during, or after the reaction with a carbonic acid derivative.

[0047] Suitable branching agents are the tri- or more than trifunctional compounds known in polycarbonate chemistry, in particular those with three or more than three phenolic OH groups.

[0048] Geeignete Verzweiger sind beispielsweise l,3,5-Tri-(4-hydroxyphenyl)-benzol, l,l,l-Tri-(4- hydroxyphenyl)-ethan, Tri-(4-hydroxyphenyl)-phenylmethan, 2,4-Bis-(4-hydroxyphenylisopropyl)- phenol, 2, 6-Bis-(2-hydroxy-5 '-methyl -benzyl)-4-methylphenol, 2-(4-Hydroxyphenyl)-2-(2,4- dihydroxyphenyl)-propan, Tetra-(4-hydroxyphenyl)-methan, Tetra-(4-(4-hydroxyphenylisopropyl)- phenoxy)-methan und l,4-Bis-((4',4"-dihydroxytriphenyl)-methyl)-benzol und 3,3-Bis-(3-methyl-4- hydroxyphenyl)-2-oxo-2,3 -dihydroindol .

[0049] The amount of branching agents to be used, if desired, is preferably 0.05 mol% to 2.00 mol%, based on the moles of dihydroxyaryl compounds used. The branching agents can either be initially introduced with the dihydroxyaryl compounds and the chain terminators in the aqueous alkaline phase or added dissolved in an organic solvent prior to phosgenation. In the case of the transesterification process, the branching agents are used together with the dihydroxyaryl compounds.

[0050] Particularly preferred polycarbonates are the homopolycarbonate based on bisphenol A, the homopolycarbonate based on l,l-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane and the copolycarbonates based on the two monomers bisphenol A and l,l-bis-(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane or the two monomers bisphenol A and 4,4'-dihydroxydiphenyl, as well as the dihydroxyaryl compounds of the formulas (I), (II) and / or (III) in which R' is each C1- to C1-alkyl, aralkyl or aryl, preferably methyl or phenyl, most preferably methyl, derived homo- or copolycarbonates, in particular with bisphenol A. Most preferably, the aromatic polycarbonate comprises a bisphenol A-based homopolycarbonate. Most preferably, the aromatic polycarbonate is a bisphenol A-based homopolycarbonate.

[0051] The total proportion of the monomer units based on the formulas (I), (II), (III), 4,4'-dihydroxydiphenyl and / or bisphenol TMC in the copolycarbonate is preferably 0.1 - 88 mol%, particularly preferably 1 - 86 mol%, very particularly preferably 5 - 84 mol% and in particular 10 - 82 mol% (based on the sum of the moles of dihydroxyaryl compounds used).

[0052] The relative solution viscosity of the copolycarbonates, determined according to ISO 1628-4: 1999, is preferably in the range of 1.15 - 1.35.

[0053] The dihydroxyaryl compounds used, as well as all other chemicals and auxiliaries added to the synthesis, may be contaminated with impurities arising from their own synthesis, handling, and storage. However, it is desirable to work with the purest raw materials possible. Copolycarbonates prepared using diphenols of the general formula (4a) are also preferred: where

[0054] R 5 represents hydrogen or Ci- to C4-alkyl, Ci- to C5-alkoxy, preferably hydrogen;

[0055] methoxy or methyl,

[0056] R 6 , R 7 , R 8 and R 9 each independently of one another represents C1- to C4-alkyl or C1- to Cn-aryl, preferably methyl or phenyl,

[0057] Y represents a single bond, SO2-, -S-, -CO-, -O-, C1- to C6-alkylene, C2- to C5-alkylidene, C1- to C12-arylene, which may optionally be condensed with further heteroatom-containing aromatic rings, or a C5- to C6-cycloalkylidene radical which may be mono- or polysubstituted by C1- to C4-alkyl, preferably a single bond, -O-, isopropylidene, or a C5- to C6-cycloalkylidene radical which may be mono- or polysubstituted by C1- to C6-alkyl,

[0058] V represents oxygen, C2- to C3-alkylene or C3- to C4-alkylidene, preferably oxygen or C5-alkylene, p, q and r each independently represent 0 or 1 when q = 0, W represents a single bond when q = 1 and r = 0, W represents oxygen, C2- to C (, -alkylene or C3- to C6-alkylidene, preferably oxygen or Cs-alkylene, when q = 1 and r = 1, W and V each independently represent C2- to C6-alkylene or C3- to C6-alkylidene, preferably C3-alkylene,

[0059] Z represents a Ci- to Ce-alkylene, preferably Cs-alkylene, o represents an average number of repeating units from 10 to 500, preferably 10 to 100, and m represents an average number of repeating units from 1 to 10, preferably 1 to 6, more preferably 1.5 to 5. It is also possible to use diphenols in which two or more siloxane blocks of the general formula (4a) are linked to one another via terephthalic acid and / or isophthalic acid to form ester groups.

[0060] Particularly preferred are (poly)siloxanes of the formulas (5) and (6) where RI is hydrogen, Ci- to C4-alkyl, preferably hydrogen or methyl and particularly preferably hydrogen,

[0061] R2 independently represent aryl or alkyl, preferably methyl,

[0062] X represents a single bond, -SO2-, -CO-, -O-, -S-, C1- to C2-alkylene, C2- to C5-alkylidene or C2- to C2-arylene, which may optionally be condensed with further aromatic rings containing heteroatoms,

[0063] X preferably represents a single bond, C1- to C5-alkylene, C2- to C5-alkylidene, C5- to C12-cycloalkylidene, -O-, -SO- -CO-, -S-, -SO2-, particularly preferably X represents a single bond, isopropylidene, C5- to C12-cycloalkylidene or oxygen, and very particularly preferably isopropylidene, n represents an average number from 10 to 400, preferably 10 and 100, particularly preferably 15 to 50 and m represents an average number from 1 to 10, preferably from 1 to 6 and particularly preferably from 1.5 to 5.

[0064] Likewise preferably, the siloxane block can be derived from the following structure

[0065] where a in formula (IV), (V) and (VI) represents an average number from 10 to 400, preferably 10 to 100 and particularly preferably 15 to 50.

[0066] It is also preferred that at least two identical or different siloxane blocks of the general formulas (IV), (V) or (VI) are linked to one another via terephthalic acid and / or isophthalic acid to form ester groups. It is also preferred if, in formula (4a), p = 0, V is Cs-alkylene, r = 1, Z is Cs-alkylene, R 8 and R 9 represents methyl, q = 1, W represents Cs-alkylene, m = 1, R 5 represents hydrogen or Ci- to C4-alkyl, preferably hydrogen or methyl, R 6 and R 7 each independently of one another represents C 1 -C 12 alkyl, preferably methyl, and o represents 10 to 500. Copolycarbonates with monomer units of the formula (4a) and in particular their preparation are described in WO 2015 / 052106 A2.

[0067] Copolycarbonates with monomer units of formula (IV) and in particular their preparation are described in WO 2015 / 052106 A2. Aromatic dicarboxylic acids suitable for the preparation of the polyester carbonates are, for example, orthophthalic acid, terephthalic acid, isophthalic acid, tert-butylisophthalic acid, 3,3'-diphenyldicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 4,4-benzophenonedicarboxylic acid, 3,4'-benzophenonedicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-diphenylsulfonedicarboxylic acid, 2,2-bis(4-carboxyphenyl)propane, and trimethyl-3-phenylindane-4,5'-dicarboxylic acid.

[0068] Of the aromatic dicarboxylic acids, terephthalic acid and / or isophthalic acid are particularly preferred.

[0069] Derivatives of dicarboxylic acids are the dicarboxylic acid dihalides and the dicarboxylic acid dialkyl esters, in particular the dicarboxylic acid dichlorides and the dicarboxylic acid dimethyl esters.

[0070] The replacement of the carbonate groups by the aromatic dicarboxylic acid ester groups occurs essentially stoichiometrically and quantitatively, so that the molar ratio of the reactants is also reflected in the finished polyester carbonate. The incorporation of the aromatic dicarboxylic acid ester groups can occur both randomly and blockwise.

[0071] The compositions according to the invention contain at least 70% by weight, preferably at least 70.5% by weight, particularly preferably at least 84% by weight of aromatic polycarbonate, i.e. they are based on aromatic polycarbonate.

[0072] Component B

[0073] Component B is a polyalkyl (meth)acrylate. It is understood that this can be a polyalkyl (meth)acrylate or a mixture of different polyalkyl (meth)acrylates. Component B does not include polymers that contain polyalkyl (meth)acrylate as part of a graft polymer. The polyalkyl (meth)acrylate is preferably a linear polymer.

[0074] The polyalkyl (meth)acrylate according to component B preferably has a weight-average molecular weight of 80,000 to 300,000 g / mol, more preferably of 100,000 to 200,000 g / mol, determined by gel permeation chromatography in tetrahydrofuran under PMMA calibration.

[0075] Component B can also be a mixture of two or more polyalkyl (meth)acrylates, one of which can also be low molecular weight. The stated weight-average molecular weight then relates accordingly to the total component B, the polyalkyl (meth)acrylate mixture. At least one of these can be low molecular weight and have a weight-average molecular weight of 1,000 to 70,000 g / mol, very particularly preferably 5,000 to 60,000 g / mol. The low molecular weight polyalkyl (meth)acrylate preferably has a proportion of 2 to 20 wt. %, in particular 5 to 10 wt. %, based on the total weight of the polyalkyl (meth)acrylate. This improves processability with the polycarbonate. The previously stated weight-average molecular weight of 80,000 to 300,000 g / mol, more preferably 100,000 to 200,000 g / mol, refers to the total polyalkyl (meth)acrylate contained in the composition according to the invention.

[0076] The polyalkyl (meth)acrylate preferably has a) 52.0 to 100.0 wt. % alkyl methacrylate repeating units having 1 to 20, preferably 1 to 12, more preferably 1 to 8, particularly preferably 1 to 4, carbon atoms in the alkyl radical, in particular methyl methacrylate, b) 0 to 40.0 wt. % alkyl acrylate repeating units having 1 to 20, preferably 1 to 12, more preferably 1 to 8, particularly preferably 1 to 4, carbon atoms in the alkyl radical, in particular methyl acrylate, and c) 0 to 8.0 wt. % styrenic repeating units of the general formula (VII) with R 1 to R 5 independently of one another hydrogen, halogen, Ci- to Ce-alkyl or C2- to C ( ,- alkenyl and R 6 hydrogen or Ci- to Ce-alkyl, where the amounts in weight percent of a, b and c add up to 100.0 wt.%, the total weight of the polyalkyl (meth)acrylate.

[0077] Most preferably, the polyalkyl (meth)acrylate comprises at least 60.0 wt.%, even more preferably at least 75.0 wt.%, in particular at least 85.0 wt.% methyl methacrylate repeat units.

[0078] Most preferably, the polyalkyl (meth)acrylate comprises 90.0 to 99.0 wt.% methyl methacrylate and 1.0 to 10.0 wt.% methyl acrylate, each based on the total weight of the polyalkyl (meth)acrylate. The proportion of component B in the compositions according to the invention is 4 wt.% to 25 wt.%, preferably 5 wt.% to 22 wt.%, more preferably 5 to 20 wt.%, in particular up to 15 wt.%, based on the total composition.

[0079] Component C

[0080] Component C of the compositions according to the invention comprises phosphorus-containing flame retardants. This can be a single phosphorus-containing flame retardant or a mixture of different phosphorus-containing flame retardants.

[0081] Preferred phosphorus-containing flame retardants are cyclic phosphazenes, phosphorus compounds of formula (10) and mixtures thereof: wherein

[0082] R 1 , R 2 , R 3 and R 4 independently of one another represent a C1- to C12-alkyl radical, each optionally halogenated and each branched or unbranched, and / or C5- to C6-cycloalkyl radical, C1- to C20-aryl radical or C7- to C12-aralkyl radical, each optionally substituted by branched or unbranched alkyl and / or halogen, preferably chlorine and / or bromine, n independently of one another represents 0 or 1, q represents a value from 0 to 30 and

[0083] X represents a mono- or polynuclear aromatic radical having 6 to 30 C atoms or a linear or branched aliphatic radical having 2 to 30 C atoms, each of which may be substituted or unsubstituted, bridged or unbridged.

[0084] Preference is given to R 1, R 2 , R 3 and R 4 independently of one another represent branched or unbranched C1- to C4-alkyl, phenyl, naphthyl or C1- to C4-alkyl-substituted phenyl. In the case of aromatic groups R 1 , R 2 , R 3 and / or R 4 These, in turn, can be substituted with halogen and / or alkyl groups, preferably chlorine, bromine, and / or C- to C-alkyl, branched or unbranched. Particularly preferred aryl radicals are cresyl, phenyl, xylenyl, propylphenyl, or butylphenyl, as well as the corresponding brominated and chlorinated derivatives thereof. X in formula (10) is preferably derived from dihydroxyaryl compounds.

[0085] X in formula (10) particularly preferably represents

[0086] (Xi) (Xu)

[0087] (Xiii) (XiV) or their chlorinated and / or brominated derivatives. Preferably, X (with the adjacent oxygen atoms) is derived from hydroquinone, bisphenol A or diphenylphenol. Likewise preferably, X is derived from resorcinol. More preferably, X is derived from bisphenol A. n in formula (10) is preferably 1. q preferably stands for 0 to 20, more preferably 0 to 10, and in the case of mixtures, for average values ​​of 0.8 to 5.0, preferably 1.0 to 3.0, further preferably 1.05 to 2.00 and particularly preferably 1.08 to 1.60.

[0088] As a phosphorus compound of the general formula (10), a compound of the formula (11) is preferred: wherein

[0089] R 1 , R 2 , R 3 and R 4 each independently of one another represents a linear or branched Ci- to Cs-alkyl radical and / or optionally substituted by linear or branched alkyl-C5- to C (, -Cycloalkyl radical. Ce- to Cio-aryl radical or C7- to Cn-aralkyl radical, n independently of one another is 0 or 1, q independently of one another is 0, 1, 2, 3 or 4, N is a number between 1 and 30,

[0090] Rs and Rs independently of one another represent a linear or branched C1- to C12-alkyl radical, preferably a methyl radical, and Y represents a linear or branched C1- to C12-alkylidene radical, a linear or branched C1- to C12-alkylene radical, a C5- to C12-cycloalkylidene radical, -O-, -S-, -SO-, SO2 or -CO-.

[0091] Phosphorus compounds of formula (10) are, in particular, tributyl phosphate, triphenyl phosphate, tricresyl phosphate, diphenyl cresyl phosphate, diphenyl octyl phosphate, diphenyl 2-ethyl cresyl phosphate, tri-(isopropylphenyl) phosphate, resorcinol-bridged oligophosphate, and bisphenol A-bridged oligophosphate. The use of oligomeric phosphoric acid esters of formula (10) derived from bisphenol A is particularly preferred.

[0092] Further preference is given to using mixtures with the same structure and different chain lengths, with the stated q-value being the mean q-value. The mean q-value is determined by determining the composition of the phosphorus compound mixture (molecular weight distribution) using high-pressure liquid chromatography (HPLC) at 40°C in a mixture of acetonitrile and water (50:50), and calculating the mean q values ​​from this.

[0093] Particularly preferably, bisphenol A-based oligophosphate (bisphenol A bis(diphenyl phosphate)) according to formula (12) with q = 1 to 20, in particular with q = 1.0 to 1.2, is contained in the compositions according to the invention.

[0094] Such phosphorus compounds are known (cf. e.g. EP 0 363 608 A1, EP 0 640 655 A2) or can be prepared in an analogous manner using known methods (e.g. Ullmanns Enzyklopädie der technischen Chemie, Vol. 18, p. 301 ff., 1979; Houben-Weyl, Methoden der organischen Chemie, Vol. 12 / 1, p. 43; Beilstein Vol. 6, p. 177).

[0095] Just as preferably as the phosphorus compounds according to formula (10), cyclic phosphazenes according to formula (13) can be used as component C: (13), where

[0096] R is the same or different and for

[0097] - an amine residue,

[0098] - an optionally halogenated, preferably fluorine-halogenated, more preferably monohalogenated, Ci- to Cx-alkyl radical, preferably methyl, ethyl, propyl or butyl radical,

[0099] - a Ci to Cs alkoxy radical, preferably a methoxy radical, ethoxy radical, propoxy radical or butoxy radical,

[0100] - a C5- to C12-cycloalkyl radical optionally substituted by alkyl, preferably C1- to C4-alkyl, and / or halogen, preferably chlorine and / or bromine,

[0101] - a Ce- to C20-aryloxy radical, preferably phenoxy radical, naphthyloxy radical, each optionally substituted by alkyl, preferably Ci- to C4-alkyl, and / or halogen, preferably chlorine, bromine, and / or hydroxy,

[0102] - a C7- to Cn-aralkyl radical, preferably phenyl-C1- to C4-alkyl radical, each optionally substituted by alkyl, preferably C1- to C4-alkyl, and / or halogen, preferably chlorine and / or bromine, or

[0103] - a halogen radical, preferably chlorine or fluorine, or

[0104] - represents an OH radical, k represents an integer from 1 to 10, preferably a number from 1 to 8, particularly preferably 1 to 5, most particularly preferably 1.

[0105] According to the invention, commercially available phosphazenes are particularly preferably used. These are usually mixtures of rings of different ring sizes.

[0106] Further preferred are, both individually and in mixtures: propoxyphosphazene, phenoxyphosphazene, methylphenoxyphosphazene, aminophosphazene, fluoroalkylphosphazenes and phosphazenes of the following structures:

[0107]

[0108] (13a-f)

[0109] In the compounds 13a-f shown above, k = 1, 2 or 3. Preferably, the proportion of phosphazenes halogen-substituted on the phosphorus, e.g. from incompletely reacted starting material, is less than 1000 ppm, more preferably less than 500 ppm.

[0110] The phosphazenes can be used alone or as a mixture. The R radical can always be the same, or two or more radicals in the formulas can be different. Preferably, the R radicals of a phosphazene are identical.

[0111] In one embodiment, only phosphazenes with the same R are used.

[0112] The proportion of tetramers (k = 2) is preferably from 2 to 50 mol%, based on component B, more preferably from 5 to 40 mol%, even more preferably from 10 to 30 mol%, particularly preferably from 10 to 22 mol%. The proportion of higher oligomeric phosphazenes (k = 3, 4, 5, 6 and 7) is preferably from 0 to 30 mol%, based on component B, more preferably from 2.5 to 25 mol%, even more preferably from 5 to 20 mol%, and particularly preferably from 6 to 15 mol%. The proportion of oligomers with k > 8 is preferably from 0 to 2.0 mol%, based on component B, and preferably from 0.10 to 1.00 mol%.

[0113] More preferably, the phosphazenes of component C fulfill all three of the above-mentioned conditions with regard to the proportions of oligomers.

[0114] Particularly preferably, phenoxyphosphazene (all R = phenoxy, formula 13g), alone or with further phosphazenes according to formula (13) is contained as component C, with a proportion of oligomers with k = 1 (hexaphenoxyphosphazene) of 50 to 98 mol%, particularly preferably 60 to 72 wt.%, based on the amount of phenoxyphosphazene, as component C. If phenoxyphosphazene is used, the proportion of oligomers with k = 2 is very particularly preferably 15 to 22 wt.% and with k > 3: 10 to 13 wt.%.

[0115] Alternatively, very particularly preferably, component C comprises a phenoxyphosphazene having a trimer content (k = 1) of 70 to 85 mol%, a tetramer content (k = 2) of 10 to 20 mol%, a content of higher oligomeric phosphazenes (k = 3, 4, 5, 6 and 7) of 3 to 8 mol% and phosphazene oligomers with k > 8 of 0.1 to 1 mol%, based on component C.

[0116] In an alternative preferred embodiment, n, defined as the arithmetic mean of k, is in the range from 1.10 to 1.75, preferably from 1.15 to 1.50, more preferably from 1.20 to 1.45, and most preferably from 1.20 to 1.40 (range limits included).

[0117] The phosphazenes and their preparation are described, for example, in EP 728 811 A2, DE 1961668 A and

[0118] WO 97 / 40092 A1. The oligomer compositions in the respective blend samples can be determined after compounding using 31Detect and quantify by P-NMR (chemical shift; 5 trimer: 6.5 to 10.0 ppm; 5 tetramer: -10 to -13.5 ppm; 5 higher oligomers: -16.5 to -25.0 ppm).

[0119] Very particularly preferably, component C comprises bisphenol-A-based oligophosphate according to formula (12) and / or cyclic phosphazene according to formula (13), most preferably component C is bisphenol-A-based oligophosphate according to formula (12) and / or cyclic phosphazene according to formula (13).

[0120] The proportion of phosphorus-containing flame retardant in the compositions according to the invention is 1.5 wt.% to 10 wt.%, preferably 2 wt.% to <8 wt.%, particularly preferably up to 6 wt.%, very particularly preferably up to <5 wt.%, extremely preferably up to 4 wt.%, based on the total composition. As the proportion of the phosphorus-containing flame retardant increases, the Vicat temperature decreases significantly.

[0121] Component D

[0122] The compositions according to the invention contain, as component D, a fluorine-containing anti-drip agent, which may be a mixture of several anti-drip agents. The total amount of anti-drip agent is 0.3 wt.% to 2 wt.%, preferably 0.4 wt.% to 1 wt.%, particularly preferably 0.5 wt.% to 1.0 wt.% of at least one anti-drip agent.

[0123] Fluorine-containing polymer, in particular polyolefin, is preferably used as the anti-drip agent.

[0124] The fluorinated polyolefins preferably used as anti-drip agents are high molecular weight and have glass transition temperatures above -30°C, generally above 100°C, and fluorine contents preferably of 65% to 76% by weight, especially of 70% to 76% by weight. Preferred fluorinated polyolefins are polytetrafluoroethylene, polyvinylidene fluoride, tetrafluoroethylene / hexafluoropropylene, and ethylene / tetrafluoroethylene copolymers. Fluorinated polyolefins are known (cf. “Vinyl and Related Polymers” by Schildknecht, John Wiley & Sons, Inc., New York, 1962, pages 484-494; “Fluoropolymers” by Wall, Wiley-Interscience, John Wiley & Sons, Inc., New York, Volume 13, 1970, pages 623-654; “Modem Plastics Encyclopedia”, 1970-1971, Volume 47, No. 10 A, October 1970, Me Graw-Hill, Inc., New York, pages 134 and 774; “Modem Plastics Encyclopedia”, 1975-1976, October 1975, Volume 52, No. 10 A, Me Graw-Hill, Inc., New York, pages 27, 28 and 472 and US Pat. No. 3,671 487 A, 3 723 373 A and 3 838 092 A).They can be produced by known processes, for example by polymerization of tetrafluoroethylene in an aqueous medium with a free radical-forming catalyst, for example sodium, potassium or ammonium peroxodisulfate, at pressures of 7 to 71 kg / cm. 2 and at temperatures from 0 to 200°C, preferably at temperatures from 20 to 100°C. Further details are described, for example, in US Pat. No. 2,393,967.

[0125] Depending on the application, the density of the fluorinated polyolefins can be between 1.2 and 2.3 g / cm 3 , preferably 2.0 g / cm 3 up to 2.3 g / cm 3 ' determined according to ISO 1183-1 (2019-09), the mean particle size is between 0.05 and 1000 pm, determined by light microscopy or white light interferometry.

[0126] Suitable tetrafluoroethylene polymer powders are commercially available products and are offered, for example, by DuPont under the trade name Teflon®.

[0127] Polytetrafluoroethylene (PTFE), either as such or in the form of a PTFE-containing composition, is particularly preferably used as a fluorine-containing anti-drip agent. If a PTFE-containing composition is used, its minimum use amount is preferably such that at least 0.15 wt.%, particularly preferably at least 0.25 wt.% PTFE is present in the total composition. PTFE-containing compositions include Hostaflon® TF2021 or PTFE blends such as Blendex® B449 (approx. 50 wt.% PTFE and approx. 50 wt.% SAN [consisting of 80 wt.% styrene and 20 wt.% acrylonitrile]) from Chemtura. PTFE or a PTFE / SAN blend is particularly preferably used as the fluorine-containing anti-drip agent.

[0128] Component E

[0129] The polycarbonate compositions according to the invention may contain one or more further additives other than components B, C and D, which are summarized here under “component E”.

[0130] Optionally (0 wt. %) to preferably 12 wt. %, more preferably up to 5 wt. %, even more preferably up to 3 wt. %, in particular 0.1 wt. % to 3 wt. %, particularly preferably 0.2 wt. % to 1 wt. %, most preferably 0.5 wt. % to 1.0 wt. % of other customary additives (“further additives”) are present, wherein these percentages by weight are based on the total weight of the composition. The group of further additives does not comprise a phosphorus-containing flame retardant according to component C. The group of further additives also comprises, in particular, no fluorine-containing anti-drip agent, since this has already been described as component D.

[0131] Such further additives, as are typically added to polycarbonates, include, in particular, thermal stabilizers, antioxidants, mold-release agents, UV absorbers, IR absorbers, impact modifiers, antistatic agents, flame retardants other than component C, optical brighteners, fillers, light scattering agents, hydrolysis stabilizers, transesterification stabilizers, (organic) dyes, (organic / inorganic) pigments, compatibilizers, and / or additives for laser marking, particularly in the amounts customary for polycarbonate-based compositions. Such additives are described, for example, in EP 0 839 623 A1, WO 96 / 15102 A1, EP 0 500 496 A1, or in the "Plastics Additives Handbook," Hans Zweifel, 5th Edition 2000, Hanser Verlag, Munich. These additives can be added individually or as a mixture.

[0132] Further preferred additives, if any, comprise one or more further additives selected from the group consisting of thermal stabilizers, antioxidants, mold release agents, organic dyes, organic pigments, inorganic pigments.

[0133] Very particularly preferably, at least one thermal stabilizer, an antioxidant and / or a mold release agent is included as a further additive.

[0134] It is understood that only such additives and only in such quantities may be added if they do not have a significantly negative impact on the inventive effect of the high CTI in combination with the good flame retardancy and preferably also the Vicat temperature, determined according to ISO 306:2014-3, VST Method B, is not reduced below 105°C, more preferably not below 110°C ± 2°C.

[0135] Particularly preferred additives are mold release agents, more preferably based on a fatty acid ester, even more preferably based on a stearic acid ester, and especially preferably based on pentaerythritol. Particular preference is given to using pentaerythritol tetrastearate (PETS) and / or glycerol monostearate (GMS). If one or more mold release agents are used, the amount is preferably up to 1.0 wt.% (inclusive), more preferably 0.01 to 0.7 wt.%, particularly preferably 0.2 to 0.60 wt.%, in each case based on the total composition.

[0136] Particularly preferred additives are also thermal stabilizers. The amount of thermal stabilizer is preferably up to 0.20 wt.%, more preferably 0.01 to 0.15 wt.%, even more preferably 0.01 to 0.1 wt.%, particularly preferably 0.025 to 0.09 wt.%, based on the total composition. Particularly suitable thermal stabilizers are phosphorus-based stabilizers selected from the group of phosphates, phosphites, phosphonites, phosphines, and mixtures thereof. Examples are triphenyl phosphite, diphenyl alkyl phosphite, phenyldialkyl phosphite, tris(nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl-pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite (Irgafos® 168), Diisodecylpentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, bis(2,4-di-cumylphenyl)pentaerythritol diphosphite (Doverphos® S-9228), bis(2,6-di-tert-butyl-4-methylphenyl)penta-erythritol diphosphite, diisodecyloxypentaerythritol diphosphite,Bis(2,4-di-tert- butyl-6-methylphenyl)-pentaerythritoldiphosphit, Bis(2,4,6-tris(tert- butylphenyl)pentaerythritoldiphosphit, Tristearylsorbitoltriphosphit, Tetrakis(2,4-di-tert- butylphenyl)-4,4'-biphenylendiphosphonit, 6-Isooctyloxy-2,4,8,10-tetra-tert-butyl-12H-dibenz[d,g]- 1,3,2-dioxaphosphocin, Bis(2,4-di-tert-butyl-6-methylphenyl)methylphosphit, Bis(2,4-di-tert-butyl- 6-methylphenyl)ethylphosphit, 6-Fluoro-2,4,8,10-tetra-tert-butyl-12-methyl-dibenz[d,g]-l,3,2- dioxaphosphocin, 2,2',2"-Nitrilo-[triethyltris(3,3',5,5'-tetra-tert-butyl-l,r-biphenyl-2,2'- diyl)phosphit], 2-Ethylhexyl(3,3',5,5'-tetra-tert-butyl-l,r-biphenyl-2,2'-diyl)phosphit, 5-Butyl-5- ethyl-2-(2,4,6-tri-tert-butylphenoxy)-l,3,2-dioxaphosphiran, Bis(2,6-di-ter-butyl-4- methylphenyl)pentaerythritol-diphosphit, Triphenylphosphin (TPP), Trialkylphenylphosphin, Bisdiphenylphosphino-ethan oder ein Trinaphthylphosphin. Sie werden allein oder im Gemisch,For example, Irganox® B900 (a mixture of Irgafos® 168 and Irganox® 1076 (antioxidant) in a ratio of 4:1) or Doverphos® S-9228 with Irganox® B900 or Irganox® 1076 are used. Triphenylphosphine (TPP), Irgafos® 168, or tris(nonylphenyl)phosphite, or mixtures thereof, are particularly preferred.

[0137] Phenolic antioxidants such as alkylated monophenols, alkylated thioalkylphenols, hydroquinones, and alkylated hydroquinones can also be used. Irganox® 1010 (pentaerythritol 3-(4-hydroxy-3,5-di-tert-butylphenyl)propionate; CAS: 6683-19-8) and Irganox 1076® (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate) are particularly preferred, preferably in amounts of 0.01-0.5 wt.%.

[0138] Furthermore, sulfonic acid esters or alkyl phosphates, e.g., mono-, di-, and / or trihexyl phosphate, triisoctyl phosphate, and / or trinonyl phosphate, can be added as transesterification inhibitors. Triisooctyl phosphate (tris-2-ethylhexyl phosphate) is preferably used as the alkyl phosphate. Mixtures of various mono-, di-, and trialkyl phosphates can also be used. Triisooctyl phosphate is preferably used in amounts of 0.003 wt.% to 0.05 wt.%, more preferably 0.005 wt.% to 0.04 wt.%, and particularly preferably 0.01 wt.% to 0.03 wt.%, based on the total composition. Examples of impact modifiers are: core-shell polymers such as ABS or MBS; olefin-acrylate copolymers such as Elvaloy® grades from DuPont or Paraloid® grades from Dow; Silicone acrylate rubbers such as the Metablen® types from Mitsubishi Rayon Co., Ltd.The compositions according to the invention already have an excellent property profile without additional impact modifiers. Compositions according to the invention are therefore preferably free of impact modifiers.

[0139] Particularly preferably, no fillers are contained in the compositions according to the invention.

[0140] Preferred compositions according to the invention consist of

[0141] A) at least 70% by weight of aromatic polycarbonate,

[0142] B) 5 wt.% to 20 wt.% polyalkyl(meth)acrylate, in particular polymethyl methacrylate,

[0143] C) 2% to 10% by weight of phosphorus-containing flame retardant,

[0144] D) 0.3% to 2% by weight of fluorine-containing anti-drip agent,

[0145] E) 0 to 12 wt.% of one or more further additives selected from the group consisting of one or more mold release agents, thermal stabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers,

[0146] Impact modifiers, optical brighteners, hydrolysis stabilizers, transesterification stabilizers, compatibilizers, additives for laser marking and mixtures thereof, wherein the wt.% data refer to the total composition and wherein the ratio of the amount of polyalkyl (meth)acrylate in wt.% and the amount of phosphorus-containing flame retardant in wt.% is < 5.

[0147] Particularly preferred compositions according to the invention consist of

[0148] A) at least 70% by weight of aromatic polycarbonate,

[0149] B) 5 wt.% to 20 wt.% polyalkyl(meth)acrylate, in particular polymethyl methacrylate,

[0150] C) 2% to 8% by weight of phosphorus-containing flame retardant,

[0151] D) 0.3% to 2% by weight of fluorine-containing anti-drip agent,

[0152] E) 0 to 5 wt.% of one or more further additives selected from the group consisting of one or more mold release agents, thermal stabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers,

[0153] Impact modifiers, optical brighteners, hydrolysis stabilizers, transesterification stabilizers, compatibilizers, additives for laser marking and mixtures thereof, wherein the wt.% data refer to the total composition and wherein the ratio of the amount of polyalkyl (meth)acrylate in wt.% and the amount of phosphorus-containing flame retardant in wt.% is < 5.

[0154] Compositions particularly preferred according to the invention consist of

[0155] A) at least 70 wt.% aromatic polycarbonate, wherein the aromatic polycarbonate is bisphenol A-based polycarbonate, more preferably the aromatic polycarbonate is bisphenol A-based homopolycarbonate,

[0156] B) 5 wt% to 20 wt% polyalkyl(meth)acrylate,

[0157] C) 2% to 8% by weight of phosphorus-containing flame retardant,

[0158] D) 0.3% to 2% by weight of fluorine-containing anti-drip agent,

[0159] E) 0 to 5 wt.% of one or more further additives selected from the group consisting of one or more mold release agents, thermal stabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers,

[0160] Impact modifiers, optical brighteners, hydrolysis stabilizers,

[0161] Transesterification stabilizers, compatibilizers, additives for laser marking and mixtures thereof, wherein the wt.% data refer to the total composition and wherein the ratio of the amount of polyalkyl (meth)acrylate in wt.% and the amount of phosphorus-containing flame retardant in wt.% is < 5.

[0162] The phosphorus-containing flame retardant used is preferably either an organophosphate, in particular one of the formula (12),

[0163] (12), where q = 1 to 20, in particular 1.0 to 1.2, or a

[0164] Phosphazene of the formula (13g)

[0165] with k = 1, 2, or 3, including mixtures thereof. It is understood that this is preferably a mixture of different oligomers of this formula, since mixtures are usually commercially available. The phosphorus-containing flame retardant is most preferably one of the formula (12) or (13g), as defined above.

[0166] Highly preferred compositions consist of

[0167] A) at least 70 wt.% aromatic polycarbonate, wherein the aromatic polycarbonate is bisphenol A-based homopolycarbonate,

[0168] B) 5 wt.% to 20 wt.% polyalkyl(meth)acrylate, C) 2 wt.% to 8 wt.% phosphorus-containing flame retardant, wherein the phosphorus-containing flame retardant is an organophosphate of the formula (12)

[0169] (12), where q = 1 to 20, in particular 1.0 to 1.2, and / or a

[0170] Phosphazene of the formula (13g) with k = 1, 2 or 3, including mixtures thereof,

[0171] D) 0.3% to 2% by weight of fluorine-containing anti-drip agent,

[0172] E) 0 to 5% by weight of one or more further additives selected from the group consisting of one or more mold release agents, thermal stabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers, optical brighteners, hydrolysis stabilizers, transesterification stabilizers, additives for laser marking and mixtures thereof, wherein the wt.% data relate to the total composition and wherein the ratio of the amount of polyalkyl (meth)acrylate in wt.% and the amount of phosphorus-containing flame retardant in wt.% is < 5, in particular < 5.

[0173] The polymer compositions according to the invention, comprising the mixed components A, B, C, D, and optionally E, can be prepared using powder premixes. Premixes of granules or granules and powders with the additives according to the invention can also be used. Premixes prepared from solutions of the mixture components in suitable solvents, optionally with homogenization in solution and subsequent removal of the solvent, can also be used. In particular, the additives referred to as component E of the compositions according to the invention can be introduced by known methods or as a masterbatch. The use of masterbatches is particularly preferred for incorporating additives and other constituents, with masterbatches based on the respective polymer matrix being used in particular.

[0174] The compositions according to the invention can, for example, be extruded. After extrusion, the extrudate can be cooled and comminuted. The combining and mixing of a premix in the melt can also take place in the plasticizing unit of an injection molding machine. In this case, the melt is transferred directly into a molded article in the subsequent step. Compositions according to the invention are preferably used for the production of molded parts for components in the renewable energy sector, in particular for high-voltage switches, inverters, relays, electronic connectors, electrical connectors, circuit breakers, components for photovoltaic applications, electric motors, heat sinks, chargers or charging plugs for electric vehicles, electrical junction boxes, smart meter housings, miniature circuit breakers, and bus bars. The invention thus also relates to molded parts that are part of a corresponding component.“Part” can be an individual element of a complex product, but also the entire element.

[0175] A molded part in the sense of the invention also includes an insulating layer made of the composition according to the invention. Such a layer can be provided, for example, on an inverter as a layer to protect against external influences. Standard insulating materials for inverters are those with a CTI of 600 V. The composition according to the invention can also be used as an insulating layer for other electrical components, e.g., transistors. The insulating layer creates, for example, a secure boundary between the transistor and a metallic heat sink.

[0176] The component is preferably designed for an operating voltage of at least 375 V, more preferably at least 400 V, in particular at least 500 V. However, it can also be designed for a typical household operating voltage of 230 V ± 23 V in Europe, although smaller distances between the electrical conductors can now be realized. The molded part is preferably used in such a way that it itself must have a tracking resistance of at least 375 V, more preferably at least 400 V, in particular at least 500 V, and most preferably at least 600 V, as described above.

[0177] The invention thus relates to molded parts consisting of or comprising regions of compositions according to the invention, as well as corresponding components comprising elements, i.e. molded parts which consist of compositions according to the invention or comprise regions consisting of compositions according to the invention.

[0178] The high tracking resistance of the polycarbonate compositions according to the invention makes it possible to realize smaller distances between two electrical conductors of a component using the polycarbonate material than was previously possible using polycarbonate.

[0179] The invention therefore also relates to an EE component, comprising a first electrical conductor and a second electrical conductor at a first distance dl and a second distance d2 from each other, which are connected via an element made of a thermoplastic composition according to the invention, which is in direct contact with the first electrical conductor and the second electrical conductor, wherein the distance dl is the shortest distance between the first electrical conductor and the second electrical conductor along the surface of the element made of the thermoplastic composition and wherein the distance d2 is the shortest distance between the first electrical conductor and the second electrical conductor through the air, wherein d2 is selected such that a flashover through the air is prevented at the respective operating voltage and wherein dl at the operating voltage U listed below is: dli(0V < U < 250V): 1.8 mm to < 2,5 mm dlii(250 V < U < 500 V) = 3.6 mm to < 5.0 mm dlii(500 V < U < 1000 V) = 7.1 mm to < 10.0 mm.,

[0180] Such small distances can only be achieved with a material that has a CTI of at least 400 V.

[0181] “Element made of a thermoplastic composition according to the invention” means that an element is present which consists of a thermoplastic composition according to the invention, i.e. the composition has not been mixed with additional components.

[0182] If the material has a CTI of 600 V, even smaller distances can be realized, so that dl then at the listed operating voltage is preferably: dli(0V < U < 250V): 1.3 mm to < 2.5 mm, dlii(250 V < U < 500 V) = 2.5 mm to < 5.0 mm, dliii(500 V < U < 1000 V) = 5.0 mm to < 10.0 mm.

[0183] Particularly preferably, dl is when using a material with a CTI of 600V at the listed operating voltage: dli(0V < U < 250V): 1.3 mm to < 1.8 mm, dlii(250 V < U < 500 V) = 2.5 mm to < 3.6 mm, dliii(500 V < U < 1000 V) = 5.0 mm to < 7.1 mm, distances which cannot be realized even with a material with a CTI of 400 or 450 V, but require a CTI of 600 V.

[0184] As is well known, the degree of contamination affects electrical conductivity. The specified distances dl and d2 are applicable in practice for components where, e.g., due to structural shielding, a degree of protection IP6K9K according to ISO 20653:2013-02 can be maintained. Thermoplastic compositions preferred according to the invention belong to insulating material group II (400 V < CTI < 600 V); particularly preferred compositions belong to insulating material group I (600 V < CTI), classified according to DIN EN 60664-1.

[0185] Various embodiments of the present invention are described below:

[0186] 1. Thermoplastic composition consisting of

[0187] A) at least 70% by weight of aromatic polycarbonate,

[0188] B) 4 wt% to 25 wt% polyalkyl(meth)acrylate,

[0189] C) 1.5 wt% to 10 wt% phosphorus-containing flame retardant,

[0190] D) 0.3% to 2% by weight of fluorine-containing anti-drip agent,

[0191] E) optionally one or more further additives, preferably one or more further additives selected from the group consisting of one or more mold release agents, thermal stabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers, impact modifiers, fillers, optical brighteners, hydrolysis stabilizers, transesterification stabilizers, flame retardants other than component C, compatibilizers, additives for laser marking and mixtures thereof, wherein the wt.% figures relate to the total composition and wherein the ratio of the amount of polyalkyl (meth)acrylate in wt.% and the amount of phosphorus-containing flame retardant in wt.% is < 10.

[0192] 2. Thermoplastic composition according to embodiment 1, wherein the ratio of the amount of polyalkyl (meth)acrylate in wt.% and the amount of phosphorus-containing flame retardant in wt.% is < 5.

[0193] 3. Thermoplastic composition according to embodiment 1 or 2, wherein the phosphorus-containing flame retardant is an organophosphate, a phosphazene or a mixture thereof.

[0194] 4. Thermoplastic composition according to one of the preceding embodiments, wherein an organophosphate of formula (11) is present as phosphorus-containing flame retardant wherein

[0195] R 1 , R 2 , R 3 and R 4 each independently of one another represents a linear or branched Ci- to Cs-alkyl radical and / or optionally substituted by linear or branched alkyl-C5- to C ( , -Cycloalkyl radical. Ce- to Cio-aryl radical or C7- to Cn-aralkyl radical, n independently of one another is 0 or 1, q independently of one another is 0, 1, 2, 3 or 4, N is a number between 1 and 30,

[0196] Rs and Rs independently of one another are linear or branched Ci- to C'x-alkyl, preferably methyl, and

[0197] Y is linear or branched C1- to C5-alkylidene, a linear or branched C1- to C5-alkyl radical, a C5- to C12-cycloalkylene radical, a C5- to C12-cycloalkylidene radical, -O-, -S-, -SO-, SO2 or -CO-.

[0198] 5. Thermoplastic composition according to one of the preceding embodiments, wherein phosphazene of formula (13g) is present as phosphorus-containing flame retardant with k = 1, 2 or 3, including mixtures thereof.

[0199] 6. Thermoplastic composition according to one of the preceding embodiments, wherein the composition contains 5 to 20 wt.% polyalkyl (meth)acrylate.

[0200] 7. A thermoplastic composition according to any one of the preceding embodiments, wherein the composition contains 0.3% to 1.0% by weight of mold release agent. 8. A thermoplastic composition according to any one of the preceding embodiments, wherein the composition contains a total of 0.02% to 0.15% by weight of thermal stabilizer and / or antioxidant.

[0201] 9. Thermoplastic composition according to one of the preceding embodiments, wherein the amount of phosphorus-containing flame retardant is 2 to 8 wt.%.

[0202] 10. Thermoplastic composition according to one of the preceding embodiments, wherein component B has a weight-average molecular weight, determined by gel permeation chromatography in tetrahydrofuran under PMMA calibration, of 80,000 to 300,000 g / mol.

[0203] 11. Thermoplastic composition according to one of the preceding embodiments, wherein component B has a weight-average molecular weight, determined by gel permeation chromatography in tetrahydrofuran under PMMA calibration, of 100,000 to 200,000 g / mol.

[0204] 12. Thermoplastic composition according to one of the preceding embodiments, wherein component B comprises 52.0 to 100.0 wt.% of alkyl methacrylate repeating units having 1 to 20, preferably 1 to 12, more preferably 1 to 8, particularly preferably 1 to 4, carbon atoms in the alkyl radical, in particular methyl methacrylate, b) 0 to 40.0 wt.% of alkyl acrylate repeating units having 1 to 20, preferably 1 to 12, more preferably 1 to 8, particularly preferably 1 to 4, carbon atoms in the alkyl radical, in particular methyl acrylate, and c) 0 to 8.0 wt.% of styrenic repeating units of the general formula (VII) with R 1 to R 5independently of one another hydrogen, halogen, C1- to C2-alkyl or C2- to C6-alkenyl and R 6 hydrogen or Ci- to Ce-alkyl, wherein the amounts in weight percent of a, b and c add up to 100.0 wt.%, the total weight of the polyalkyl (meth)acrylate. Thermoplastic composition according to one of the preceding embodiments, consisting of

[0205] A) at least 70% by weight of aromatic polycarbonate,

[0206] B) 5 wt% to 20 wt% polyalkyl(meth)acrylate,

[0207] C) 2% to 8% by weight of phosphorus-containing flame retardant,

[0208] D) 0.3% to 2% by weight of fluorine-containing anti-drip agent,

[0209] E) 0 to 5 wt.% of further additives selected from the group consisting of one or more mold release agents, thermal stabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers, impact modifiers, optical brighteners, hydrolysis stabilizers, compatibilizers, additives for laser marking and mixtures thereof, wherein the wt.% data relate to the total composition and wherein the ratio of the amount of polyalkyl (meth)acrylate in wt.% and the amount of phosphorus-containing flame retardant in wt.% is < 5. Thermoplastic composition according to one of the preceding embodiments, wherein the polyalkyl (meth)acrylate has a number-average molecular weight of 80,000 to 300,000 g / mol, determined in THF under PMMA calibration, and a) 52.0 to 100.0 wt. % methyl methacrylate repeat units and b) 0 to 40.0 wt. % methyl acrylate repeat units and c) 0 to 8.0 wt.-% styrenic repeating units of the general formula (VII). with R 1 to R 5 independently of one another hydrogen, halogen, C1- to C1-alkyl or C2- to C1-alkenyl and R 6Hydrogen or C1- to C18-alkyl, wherein the amounts in weight percent of a, b, and c add up to 100 wt.%, wherein 100 wt.% is the total weight of the polyalkyl (meth)acrylate. Thermoplastic composition according to one of the preceding embodiments, wherein the further additives are selected from the group consisting of one or more mold release agents, thermal stabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers, optical brighteners, hydrolysis stabilizers, transesterification stabilizers, additives for laser marking, and mixtures thereof. Molded part consisting of or comprising a region of a thermoplastic composition according to one of the preceding embodiments. Molded part according to embodiment 16, wherein the molded part is part of a high-voltage switch, inverter, relay, electronic connector, electrical connector, circuit breaker, a photovoltaic system, an electric motor,a heat sink, an electric vehicle charger, an electrical junction box, a smart meter housing, a miniature circuit breaker, a busbar. Molded part according to embodiment 16 or embodiment 17, wherein the molded part is part of an EE component designed for an operating voltage of at least 375 V. Molded part according to one of embodiments 16 to 18, wherein the molded part is part of an EE component designed for an operating voltage of at least 400 V. Molded part according to one of embodiments 16 to 19, wherein the molded part is part of an EE component designed for an operating voltage of at least 500 V. Molded part according to one of embodiments 16 to 20, wherein the molded part is part of an EE component designed for an operating voltage of at least 600 V. EE component,comprising a first electrical conductor and a second electrical conductor at a first distance dl and a second distance d2 from each other, which are connected via an element made of a thermoplastic composition according to one of embodiments 1 to 15, which is in direct contact with the first electrical conductor and the second electrical conductor, wherein the distance dl is the shortest distance between the first electrical conductor and the second electrical conductor along the surface of the element made of the thermoplastic composition and wherein the distance d2 is the shortest distance between the first electrical conductor and the second electrical conductor through the air, wherein d2 is selected such that flashover through the air is prevented at the respective operating voltage and wherein dl at the operating voltage U listed below is: dli(0V < U < 250V): 1.3 mm to < 2.5 mm dlii(250 V < U < 500 V) = 2.5 mm to < 5,0 mm dliii(500 V < U < 1000 V) = 5.0 mm to < 10.0 mm.,

[0210] 23. EE component according to embodiment 22, where dl at the operating voltage U listed below is: dli(0V < U < 250V): 1.3 mm to < 1.8 mm, dlii(250 V < U < 500 V) = 2.5 mm to < 3.6 mm, dliii(500 V < U < 1000 V) = 5.0 mm to < 7.1 mm.

[0211] 24. EE component according to one of embodiments 22 or 23, where d2 > 1.2 mm.

[0212] 25. EE component according to one of the embodiments 22 to 24, wherein a degree of protection IP6K9K according to ISO 20653:2013-02 is present.

[0213] 26. EE component according to one of embodiments 22 to 25, designed for an operating voltage of at least 400 V, preferably at least 500 V, particularly preferably at least 600 V.

[0214] 27. EE component according to one of claims 22 to 26, wherein the element made of a thermoplastic composition according to one of embodiments 1 to 15 is a molded part according to one of embodiments 16 to 21.

[0215] 28. Use of the combination of 4 to 25 wt.% polyalkyl (meth)acrylate, 0.3 to 2 wt.% fluorine-containing anti-drip agent and 1.5 to 10 wt.%, preferably 2 to 8 wt.% phosphorus-containing flame retardant, wherein the wt.% data relate to the resulting total composition, for achieving a CTI of 600V and a UL94 V0 classification at 2 mm in a thermoplastic, polycarbonate-based composition.

[0216] 29. Thermoplastic composition according to any one of the preceding embodiments 1 to 15, molded part according to any one of the preceding embodiments 16 to 21, EE component according to any one of the embodiments 22 to 27 or use embodiment according to 28, wherein the aromatic polycarbonate is bisphenol A-based homopolycarbonate.

[0217] Examples

[0218] 1. Description of raw materials and test methods a) Raw materials

[0219] Component Al: Linear polycarbonate based on bisphenol A with a melt volume flow rate of 12 cm 3 / (10 min) (according to ISO 1133:2012-03, at a test temperature of 300°C and 1.2 kg load), containing as component E-3 250 ppm (= 0.025 wt.%, based on the total weight of component A) thermal stabilizer triphenylphosphine.

[0220] Component A-2: Linear polycarbonate based on bisphenol A with a melt volume flow rate of 6 cm 3 / (10 min) (according to ISO 1133:2012-03, at a test temperature of 300°C and a load of 1.2 kg).

[0221] Component Bl : Polyalkyl(meth)acrylate with a glass transition temperature of 117°C, measured according to ISO 11357-1 / -2, with 1 wt.% methyl acrylate content, M w : 147,000 g / mol, determined by gel permeation chromatography in tetrahydrofuran using PMMA calibration, available under the trade name Plexiglas® 8H from Röhm GmbH.

[0222] Component Cl: Organophosphate of formula (12) with q = 1.0 - 1.2. Bisphenol A bis(diphenyl phosphate) from Adeka.

[0223] Component C-2: Phenoxycyclophosphazene Rabitle FP110 from Fushimi Pharmaceutical, Japan, formula (13g), with a trimer content (k = 1) of about 68 mol%.

[0224] Component Dl: SAN-encapsulated polytetrafluoroethylene ADS5000 (approx. 50 wt.% PTFE (fluorine-containing anti-drip agent) and approx. 50 wt.% SAN) from Chemical Innovation Co., Ltd. Thailand.

[0225] Component El: Mold release agent. Pentaerythritol tetrastearate, commercially available as Loxiol VPG 861 from Emery Oleochemicals Group.

[0226] Component E-2: Mixture of thermal stabilizer and antioxidant. Irganox® B900 from BASF (mixture of Irgafos® 168 (tris-(2,4-di-tert-butylphenyl) phosphite) and Irganox® 1076 (octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate) in a weight ratio of 4:1). b) Test methods

[0227] Comparative tracking index (CTI):

[0228] To determine the tracking resistance, the compositions described here were tested using the rapid test method based on IEC 60112:2009. For this purpose, a 0.1% ammonium chloride test solution (395 ohm* cm resistance) was applied dropwise between two electrodes spaced 4 mm apart onto the surface of test specimens measuring 60 mm x 40 mm x 4 mm at intervals of 30 s. A test voltage was applied between the electrodes, which varied over the course of the test. The first test specimen was tested at a starting voltage of 300 V or 350 V. A maximum of 50 drops (one drop every 30 s) were applied per voltage, provided no tracking current > 0.5 A occurred over 2 s or the specimen burned. After 50 drops, the voltage was increased by 50 V, and a new test specimen was tested at this higher voltage, following the procedure described above.This process was continued until either 600 V was reached or leakage current or fire occurred. If one of the aforementioned effects occurred with fewer than 50 drops, the voltage was reduced by 25 V and a new test specimen was tested at this lower voltage. The voltage was reduced until the test passed with 50 drops without leakage current or fire. This procedure determined the maximum possible voltage at which a composition could withstand 50 drops of the test solution without leakage current occurring. Finally, four more test specimens, each with 50 drops, were tested at the determined maximum voltage for confirmation. This confirmed value is given in the examples as the CTI. A 100-drop value was not determined, hence the “rapid test method based on” the aforementioned standard.

[0229] PTI (“proof tracking index”):

[0230] The PTI is tested based on IEC 60112:2009, modified as described below. For this purpose, a 0.1% ammonium chloride test solution (395 ohm* cm resistance) was applied dropwise between two electrodes spaced 4 mm apart onto the surface of test specimens measuring 60 mm x 40 mm x 4 mm at intervals of 30 seconds. In contrast to the CTI test, a fixed test voltage is applied between the electrodes in the PTI test, and a total of five test specimens are tested at the respective voltage. A maximum of 50 drops (one drop every 30 seconds) were applied per test specimen, provided no leakage current of > 0.5 A occurred for 2 seconds or the specimen burned.

[0231] Flame resistance:

[0232] The flame retardancy testing of the polycarbonate compositions was conducted according to Underwriters Laboratory Method UL 94 V in thicknesses of 1.5 mm and 2 mm. The tested test specimens were previously conditioned for 7 days at 20% relative humidity and an ambient temperature of 70°C.

[0233] Different fire classes are assigned depending on the behavior of the test specimens. These include the time until the flame extinguishes, resistance to dripping, and whether a material drips while burning. The classes determined based on these criteria are designated VO, VI, and V2 and are determined based on a total of five tested test specimens.

[0234] V0: The test specimen, positioned with its longitudinal axis 180° (vertical) to the flame, has an average afterburn time of no more than 10 seconds after the flame is removed and does not produce dripping plastic particles that could ignite cotton wool underneath the test specimen. The total afterburn time of five test specimens, each exposed to the flame twice, is a maximum of 50 seconds.

[0235] VI: In contrast to V0, the average maximum afterburn time here is < 30 seconds, whereby no particles are allowed to drop off and ignite the cotton wool. The total afterburn time of five test specimens, each exposed to flame twice, is < 250 seconds.

[0236] V2: In contrast to V0 and VI, this classification produces dripping plastic particles that ignite the cotton wool. The individual afterburn times are < 30 seconds, and the total afterburn time of five test specimens, each exposed to flame twice, is < 250 seconds. NB: The test does not provide a flame retardant classification if the afterburn times are exceeded.

[0237] Heat resistance:

[0238] The heat distortion temperature of the compositions was determined using the Vicat softening temperature (Method B, test force 50 N, heating rate 50 K / h) on test specimens with dimensions 80 mm x 10 mm x 4 mm according to ISO 306:2014-3.

[0239] 2. Preparation of the test specimens

[0240] The compositions were produced on a 25 mm Coperion twin-screw extruder with a throughput of 20 kg / h. The polymer melt temperatures in the extruder ranged from 260 to 280°C at an average screw speed of 225 rpm.

[0241] The test specimens measuring 60 mm x 40 mm x 4 mm were manufactured from the molding compounds using standard injection molding processes at a melt temperature of 280°C and a mold temperature of 80°C. 3. Results

[0242] In the following tables, "ng" means "not tested" and "nb" means "failed." The notation "*" means "taken from UL Yellow Card."

[0243] Table 1 ng: not tested, n. failed

[0244] Pure bisphenol-A-based polycarbonate has a CTI of 250 V without mold release agents (VI) and an inherent flame retardancy of V2, measured according to UL94. As the results from Table 1 and Table 2 show, the addition of 5 wt.% polyalkyl (meth)acrylate leads to a significant improvement in the tracking resistance of polycarbonate, but also to a significant deterioration in flame retardancy (cf. VI and V-6). Although V-3 and V-4 achieve a result of 600 V in the CTI rapid test, the robustness of these compositions is significantly worse than those with additional PMMA. This is particularly evident in the PTI measurement, which tests a larger number of test specimens at a defined voltage (operating voltage) and reveals the weak points with regard to the voltage ranges. In this case, compositions without PMMA are particularly susceptible to failure at 300 V and 350 V, but robust at a higher voltage of 600 V.A comparable PMMA-containing composition (E-14) shows this robustness even at low voltages of 300 V and 350 V (see Table 2).

[0245] The addition of mold release agents and heat stabilizers in polycarbonate compositions negatively impacts the Vicat softening temperature and fire behavior, although the CTI is only slightly improved (see V-2). However, the flame retardancy of the composition does not improve with the addition of polyalkyl (meth)acrylate; in fact, it worsens (V-6), so additional flame retardant additives must be added here as well. As V-5 shows, the sole addition of a phosphorus-containing flame retardant is not sufficient to achieve a V0, but it does significantly reduce the CTI. Only the combination of an anti-drip agent with a phosphorus-containing flame retardant and polyalkyl (meth)acrylate can ultimately ensure the desired property profile of high CTI, good flame protection, robust CTI, and a sufficiently high Vicat temperature (see E-7 to E-9). This is evident not only with BDP but also with phosphazene (E-10) as a flame retardant.

[0246] Table 2 .g.: not tested, nb: failed

[0247] Higher amounts of polyalkyl(meth)acrylate also have a positive effect on the CTI, although the fire behavior deteriorates significantly with increasing PMMA content. Although a CTI of 600 V is achieved at 10 wt.% and 20 wt.% polyalkyl(meth)acrylate, the addition of at least 2 wt.% flame retardant (E-12), in combination with an anti-drip agent, is necessary to achieve a VO classification according to UL 94 V. As E-16 shows, this can also be achieved using phosphazene instead of BDP as the flame retardant. The addition of mold release agent and thermal stabilizer (cf. E-13 and E-15) only impairs the result, as already described above, with regard to the Vicat softening temperature. From 20 wt.% polyalkyl(meth)acrylate, a VO classification can only be achieved with larger amounts of flame retardant (cf. V-18 with V-20 and V-21). Increasing the amount of anti-drip agent at high polyalkyl (meth)acrylate contents has no further effect on flame retardancy (V-19).As the results from Tables 1 and 2 show, the ratio of polyalkyl (meth)acrylate to phosphorus-containing flame retardant should preferably be a maximum of 5. A smaller ratio and thus more flame retardant is unproblematic with regard to the CTI, but at the same time means significantly lower Vicat temperatures.

Claims

Patent claims:

1. Thermoplastic composition consisting of A) at least 70 wt.% aromatic polycarbonate, B) 4 wt.% to 25 wt.% polyalkyl(meth)acrylate, C) 1.5 wt.% to 10 wt.% phosphorus-containing flame retardant, D) 0.3 wt.% to 2 wt.% fluorinated anti-drip agent, E) optionally one or more further additives selected from the group consisting of one or more release agents, thermostabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers, impact modifiers, optical brighteners, hydrolysis stabilizers, transesterification stabilizers, compatibility enhancers, laser marking additives and mixtures thereof, wherein the wt. % values ​​refer to the total composition and wherein the ratio of the amount of polyalkyl(meth)acrylate in wt. % to the amount of phosphorus-containing flame retardant in wt. % is < 10.

2. Thermoplastic composition according to claim 1, wherein the ratio of the amount of polyalkyl(meth)acrylate in wt.% and the amount of phosphorus-containing flame retardant in wt.% is < 5.

3. Thermoplastic composition according to claim 1 or 2, wherein the phosphorus-containing flame retardant is an organophosphate, a phosphazene or a mixture thereof.

4. Thermoplastic composition according to one of the preceding claims, wherein an organophosphate of formula (11) is included as the phosphorus-containing flame retardant. wherein R 1 , R 2 , R 3 and R 4 each independently a linear or branched Ci to Cx alkyl group and / or optionally by linear or branched alkyl-substituted C5 to G,- cycloalkyl group, Ce to Cio aryl group or C7 to Ci2 aralkyl group, n independently 0 or 1, q independently 0, 1, 2, 3 or 4, N is a number between 1 and 30, Rs and Re independently linear or branched Ci- to C-alkyl groups, preferably methyl groups, and Y linear or branched Ci- to CS-alkylidcn. a linear or branched Ci- to C7- alkylene residue, C5- to Ci2-cycloalkylene residue, C5- to Ci2-cycloalkylidene residue, -O-, -S-, -SO-, SO2 or -CO- 5. Thermoplastic composition according to any one of the preceding claims, wherein phosphazene of formula (13g) is included as the phosphorus-containing flame retardant. with k = 1, 2 or 3, including mixtures thereof.

6. Thermoplastic composition according to any one of the preceding claims, wherein the Composition contains 5 to 20 wt% polyalkyl(meth)acrylate.

7. Thermoplastic composition according to any one of the preceding claims, wherein the Composition contains 0.3 wt.% to 1.0 wt.% demolding agent.

8. Thermoplastic composition according to any one of the preceding claims, wherein the The composition contains a total of 0.02 to 0.15 wt% thermostabilizer and / or antioxidant.

9. Thermoplastic composition according to any of the preceding claims, wherein the amount of phosphorus-containing flame retardant is 2 to 8 wt.%.

10. Thermoplastic composition according to any one of the preceding claims, consisting of A) at least 70 wt.% aromatic polycarbonate, B) 5 wt.% to 20 wt.% polyalkyl(meth)acrylate, C) 2% to 8% by weight of phosphorus-containing flame retardant, D) 0.3 wt.% to 2 wt.% fluorinated anti-drip agent, E) 0 to 5 wt.% further additives selected from the group consisting of one or more release agents, thermostabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers, optical brighteners, hydrolysis stabilizers, laser marking additives and mixtures thereof, wherein the wt.% values ​​refer to the total composition and wherein the ratio of the amount of polyalkyl(meth)acrylate in wt.% and the amount of phosphorus-containing flame retardant in wt.% is < 5. Thermoplastic composition according to any one of the preceding claims, wherein the polyalkyl(meth)acrylate has a number-average molecular weight of 80,000 to 300,000 g / mol, determined in THF under PMMA calibration, and comprises a) 52.0 to 100.0 wt% methyl methacrylate repeat units, b) 0 to 40.0 wt% methyl acrylate repeat units, and c) 0 to 8.0 wt% styrenic repeat units of general formula (VII). with R 1 to R 5 independently of each other hydrogen, halogen, Ci to Ce alkyl or C2 to Ce alkenyl as well as R 6 comprising hydrogen or Ci- to Ce-alkyl, wherein the amounts in weight percent of a, b and c add up to 100 wt.%, where 100 wt.% is the total weight of the polyalkyl(meth)acrylate. Molded part consisting of or comprising a region of a thermoplastic composition consisting of A) at least 70 wt.% aromatic polycarbonate, B) 4 wt.% to 25 wt.% polyalkyl(meth)acrylate, C) 1.5 wt.% to 10 wt.% phosphorus-containing flame retardant, D) 0.3 wt.% to 2 wt.% fluorinated anti-drip agent, E) optionally one or more further additives selected from the group consisting of one or more demolding agents, thermostabilizers, antioxidants, dyes, pigments, UV absorbers, IR absorbers, impact modifiers, optical brighteners, hydrolysis stabilizers, transesterification stabilizers, compatibility enhancers, additives for Laser marking and its mixtures, where the wt. % values ​​refer to the total composition and where the ratio of the amount of polyalkyl(meth)acrylate in wt. %, to the amount of phosphorus-containing flame retardant in wt. %, is < 10.

13. Molded part according to claim 12, wherein the molded part is part of an EE component comprising the group consisting of high-voltage switches, inverters, relays, electronic connectors, electrical connectors, circuit breakers, photovoltaic systems, electric motors, heat sinks, chargers or charging plugs for electric vehicles, electrical junction boxes, smart meter housings, miniature disconnect switches, and busbars, wherein the EE component preferably has a protection class IP6K9K according to ISO 20653:2013-02.

14. Use of the combination of 4 to 25 wt% polyalkyl(meth)acrylate, 0.3 to 2 wt% fluorinated anti-drip agent and 1.5 to 10 wt% phosphorus-containing flame retardant, wherein the wt% values ​​refer to the resulting total composition, to achieve a CTI of 600V and a UL94 VO classification at 2 mm in a thermoplastic composition containing at least 70 wt% aromatic polycarbonate.

15. EE component comprising a first electrical conductor and a second electrical conductor at a first distance dl and a second distance d2 from each other, which are connected via a thermoplastic composition according to any one of claims 1 to 11, which is in direct contact with the first electrical conductor and the second electrical conductor, wherein the distance dl is the shortest distance between the first electrical conductor and the second electrical conductor along the surface of the thermoplastic composition and wherein the distance d2 is the shortest distance between the first electrical conductor and the second electrical conductor through the air, wherein d2 is selected such that arcing through the air is prevented at the respective operating voltage and wherein dl is, at the following operating voltage U, dli(0V < U < 250V): 1.3 mm to < 2.5 mm dli(250 V < U < 500 V) = 2.5 mm to < 5.0 mm dliii(500 V < U < 1000 V) = 5.0 mm to < 10.0 mm.

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