Ee device comprising a composite polycarbonate element having high cti

Abstract

The invention relates to an EE device comprising, depending on the operating voltage applied, different distance ranges between the electrical conductors, the distances being so small that already the material used between the electrical conductors results in a very high comparative tracking index. Surprisingly, this material is a polycarbonate-based material the comparative tracking index of which is significantly increased when relatively small amounts of fluorine-containing anti-dripping agent and phosphorus-based retardant are added.

Description

[0001] EE component with polycarbonate composite element with high CTI

[0002] The invention relates to renewable energy components made of a polymer material with high tracking resistance.

[0003] In applications where the plastic is in direct contact with the electrical conductors, high resistance to creeping currents under voltage load is required to prevent short circuits and thus fire within the component. Comparative tracking index (CTI) generally describes the resistance of a plastic material to environmental influences. The CTI value is a measure of the tendency of a plastic to form electrically conductive paths on the surface when exposed to environmental influences such as moisture and contamination, thereby promoting the resulting electrical creepage 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 modern electromobility applications.A further advantage of materials with a high CTI value is the possibility of placing electrical conductors closer together in an EE component without risking a short circuit, which in turn enables the reduction of component dimensions and thus more compact designs and weight savings.

[0004] Polycarbonate is a material that is fundamentally interesting as a polymer material due to its high impact strength and high heat resistance, but has not yet been considered for such applications due to its intrinsically low tracking resistance. In contrast to other thermoplastic polymers such as polystyrene, polyester, etc., polycarbonate itself has a very low tracking resistance. Due to the high proportion of aromatic structures, polycarbonate has a relatively high tendency to carbonization. The CTI of pure polycarbonate is approximately 250 V or even lower (F. Acquasanta et al., Polymer Degradation and Stability, 96 (2011), 2098-2103).

[0005] For numerous applications in the electrical / electrical (EE) sector, e.g. in the area of ​​electromobility, a higher CTI of the materials used is required for safety reasons. This is due, for example, to the fact that housings made of one material can be dented in the event of a collision, e.g. due to an accident, and thus come into contact with electrical conductors and possibly form a bridge between them. In such a case, a short circuit should ideally not occur. Other applications are per se operated with voltages of 400 V and higher, so that correspondingly tracking-resistant materials are required. In the area of ​​e-mobility, the current standard is already an operating voltage of 400 V, e.g. where fast charging times are required, and a further increase is likely.Therefore, polycarbonate has not yet been considered as a material for a wide range of applications that require high tracking resistance of the material.

[0006] The higher the tracking resistance of a material, the smaller the distances between the electrical conductors of an EE component, depending on the applied operating voltage. This is important, for example, in batteries, since reducing the distances between two conductors by just a few fractions of a millimeter can significantly increase the capacity or energy density of the battery. At the same time, the use of the otherwise attractive polycarbonate would also be desirable for corresponding EE applications.

[0007] The objective was therefore to provide EE components with a polycarbonate material connecting the electrical conductors, which exhibits a high CTI of at least 400 V, preferably 600 V, preferably determined according to the rapid test method based on IEC 60112:2009. Due to the application area and the heat generation in EE components, the thermoplastic compositions used should preferably also exhibit good heat resistance, in particular a Vicat softening temperature, determined according to ISO 306:2014-3, VST Method B, of at least 100°C, preferably at least 115°C.

[0008] Surprisingly, it was found that polycarbonate-based compositions containing bisphenol A-based polycarbonate, fluorine-containing anti-drip agent, and phosphorus-containing flame retardant in certain amounts exhibit such high tracking resistance that, using these polycarbonate compositions, smaller distances can be achieved between two electrical conductors of a component than was previously conceivable using polycarbonate. This was particularly surprising because polycarbonate itself has a low tracking resistance and the amounts of additives added are relatively small compared to the polycarbonate content of the resulting compositions.

[0009] The invention therefore relates to an EE component, comprising a first electrical conductor and a second electrical conductor at a first distance d 1 and a second distance d 2 from each other, which are connected via a thermoplastic composition Z which is in direct contact with the first electrical conductor and the second electrical conductor, wherein the distance d 1 is the shortest distance between the first electrical conductor and the second electrical conductor along the surface of the thermoplastic material M and wherein the distance d 2 is the shortest distance between the first electrical conductor and the second electrical conductor through the air, wherein d 2 is selected such that a flashover through the air is prevented at the respective operating voltage, wherein d 1 at the operating voltage U listed below is: d 11 (0 V < U < 250 V): 1.3 mm to < 2.5 mm d 11 (250 V < U < 500 V) = 2.5 mm to < 5.0 mm d 11 (500 V < U < 1000 V) = 5.0 mm to < 10.0 mm and wherein the thermoplastic composition Z comprises the following components:,

[0010] A) at least 80 wt.% aromatic polycarbonate based on bisphenol A, B) 0.25 wt.% to 5 wt.% fluorine-containing anti-drip agent containing polytetrafluoroethylene,

[0011] C) at least 2% by weight of phosphorus-containing flame retardant, wherein the quotient of the amount of phosphorus-containing flame retardant and the amount of PTFE is < 40 and wherein, when the phosphorus-containing flame retardant b1) is an organophosphate, the amount of phosphorus-containing flame retardant is 2 to 12% by weight and when the phosphorus-containing flame retardant b2) is a phosphazene, the amount of phosphorus-containing flame retardant is 2 to 9% by weight and wherein the thermoplastic composition Z is free from flame retardants selected from the group of alkali metal, alkaline earth metal and ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide or sulfonimide derivatives.

[0012] Such low lower limits for the distances between the electrical conductors can only be achieved with a material that has a CTI of at least 600 V. The upper range of these low distance ranges can also only be achieved if the material used has a CTI of at least 400 V.

[0013] Even the distance ranges listed below can only be realized at the specified operating voltages if the material has a CTI of at least 400 V: dli(0V < U < 250V): 1.8 mm to < 2.5 mm dlii(250 V < U < 500 V) = 3.6 mm to < 5.0 mm dliii(500 V < U < 1000 V) = 7.1 mm to < 10.0 mm.

[0014] Particularly preferably, when using a material with a CTI of 600V, as described as part of the invention, dl is 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 are not realizable even with a material with a CTI of 400 V or 450 V, but require a CTI of 600 V.

[0015] It is therefore possible to produce renewable energy components with polycarbonate material between two electrical conductors with smaller distances than previously thought possible.

[0016] The selection of d2 is within the skill of the expert. Preferably, d2 is at least 1.2 mm. As is well known, the degree of contamination affects electrical conductivity. The specified distances dl and d2 are practical for components that, for example, meet protection class IP6K9K according to ISO 20653:2013-02, due to structural shielding.

[0017] The thermoplastic compositions used for the EE component according to the invention represent a selection such that, due to their high tracking resistance, they are assigned to insulating material group II (400 V < CTI < 600 V), particularly preferably to insulating material group I (600 V < CTI), classified according to DIN EN 60664-1.

[0018] Due to the high tracking resistance of the material used, the EE component according to the invention is preferably used for EE assemblies designed for an operating voltage of at least 400 V, possibly even 600 V. Corresponding EE assemblies are therefore also the subject of the invention.

[0019] The EE component according to the invention is preferably part of a high-voltage switch, an inverter, a relay, an electronic connector, an electrical connector, a circuit breaker, a photovoltaic system, an electric motor, a heat sink, a charger or charging plug for electric vehicles, an electrical junction box, a smart meter housing, a miniature circuit breaker, or a bus bar. "Part of" here means that it can be an individual element of a complex product, a component group, but it can also be the entire element, as is conceivable, for example, in the case of an "electronic connector."

[0020] The thermoplastic composition Z used for the EE component according to the invention necessarily comprises components A, B and C. Optionally, further components can also be added, for example additives according to component D, provided they do not have a negative impact on the desired effect of high tracking resistance.

[0021] The invention also relates to the use of corresponding compositions to achieve a CTI of at least 600 V. It is understood that the preferred, further preferred, particularly preferred, etc. embodiments described for the EE component, which may also relate to aspects of the thermoplastic composition Z, also apply to the use according to the invention.

[0022] Such a targeted use also occurs, for example, when a corresponding composition Z is used for an insulation layer that, due to its application, requires a CTI of 600 V. Such an insulation layer can, for example, be provided on an inverter as a layer to protect against external influences. Standard insulation materials for inverters are those with a CTI of 600 V. The composition according to the invention can also be used as an insulation layer for other electrical components, e.g., transistors. The electrical components of a transistor are protected by overmolding with a plastic with a high CTI. The plastic protects the electrical components both from contact and from unwanted electrical interaction with adjacent metallic components—such as a metallic heat sink—or electrical components.

[0023] Transistors are also often mounted directly onto a heat sink due to the high heat generation during operation. Here, too, the thermoplastic compound Z, which is placed between the heat sink and the transistor, ensures safe operation.

[0024] Another field of application is mounting brackets for busbars, for which materials with a high CTI must also be used. The mounting brackets essentially have two functions: they fix the busbars within the component group to prevent them from changing their position during operation, and they act as spacers to enable multiple busbars to be run in parallel. Here too, the distance between the two bars must be sufficiently large to prevent flashover. In addition, tracking on the surface of the mounting bracket between the busbars, but also between the busbar and other metallic components, e.g. the screws used to attach the mounting bracket to the structure below, must be prevented. Mounting brackets with a high CTI can increase both the component and the energy density.

[0025] Plugs, connectors, and sockets pose a high risk of current leakage, which can lead to electrical failure and potentially fire. An enclosure that seals live wires can improve the situation, as the degree of contamination is low. Charger plugs and USB-C connectors are at increased risk because the current-carrying conductors cannot be covered or sealed and are also exposed to contaminants such as sweat, moisture, fabric particles, dust, and other materials. A material with a high CTI value is necessary to provide sufficient protection against tracking, but also to enable miniaturization and increased power density.

[0026] The components of the composition used according to the invention are explained in more detail below:

[0027] Component A

[0028] Component A of the thermoplastic compositions according to the invention is bisphenol A-based polycarbonate. "Bisphenol A-based" preferably means that the polycarbonate comprises at least 50 wt.%, more preferably at least 70 wt.%, and even more preferably at least 90 wt.% of monomer units based on bisphenol A. Component A is preferably bisphenol A homopolycarbonate, i.e., an aromatic polycarbonate based on the sole monomer unit bisphenol A.

[0029] The melt volume flow rate MVR of the aromatic bisphenol A homopolycarbonate 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 to 21 cm 3 / (10 min), particularly preferably 10 to 19 cm 3 / (10 min), most preferably 11 to 15 cm 3 / (10 min). If different polycarbonates are used, these values ​​refer to the mixture of bisphenol A homopolycarbonates.

[0030] Details of the production of polycarbonates have been documented in numerous patents for about 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.

[0031] 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 is also possible by reacting dihydroxyaryl compounds with, for example, diphenyl carbonate.

[0032] In the case of bisphenol A homopolycarbonate, only bisphenol A is used as a dihydroxyaryl compound.

[0033] In the production of bisphenol A homopolycarbonate, preferred chain terminators are phenols that are mono- or polysubstituted with C1- to C50-alkyl radicals, linear or branched, preferably unsubstituted, or with tert-butyl. Particularly preferred chain terminators are phenol, cumylphenol, and / or p-tert-butylphenol. 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.

[0034] In principle, the homopolycarbonate can also be branched.

[0035] 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. Suitable branching agents are, for example, 1,3,5-tri-(4-hydroxyphenyl)-benzene, 1,1,1-tri-(4-hydroxyphenyl)-ethane, tri-(4-hydroxyphenyl)-phenylmethane, 2,4-bis-(4-hydroxyphenylisopropyl)-phenol, 2, 6-bis-(2-hydroxy-5'-methyl-benzyl)-4-methylphenol, 2-(4-Hydroxyphenyl)-2-(2,4-dihydroxyphenyl)-propane, tetra-(4-hydroxyphenyl)-methane, tetra-(4-(4-hydroxyphenylisopropyl)-phenoxy)-methane and l,4-bis-((4',4"-dihydroxytriphenyl)-methyl)-benzene and 3,3-bis-(3-methyl-4- hydroxyphenyl)-2-oxo-2,3-dihydroindole.

[0036] The amount of branching agents to be used optionally is preferably 0.05 mol% to 2.00 mol%, based on moles of bisphenol A used in each case.

[0037] The branching agents can either be added together with the bisphenol A and the chain terminators in the aqueous alkaline phase or dissolved in an organic solvent before phosgenation. In the case of the transesterification process, the branching agents are used together with the bisphenol A.

[0038] The thermoplastic compositions according to the invention contain at least 80% by weight, preferably at least 83% by weight, particularly preferably at least 90% by weight of aromatic bisphenol A-based polycarbonate, preferably bisphenol A homopolycarbonate, and are therefore based on such aromatic polycarbonate.

[0039] Component B

[0040] The thermoplastic compositions Z contain, as component B, a fluorine-containing anti-drip agent containing polytetrafluoroethylene (PTFE), which may be a mixture of several anti-drip agents. The total amount of anti-drip agent is 0.25 wt.% to 5 wt.%, preferably 0.4 wt.% to 1.6 wt.%, particularly preferably 0.045 wt.% to 1.0 wt.% of at least one anti-drip agent.

[0041] Fluorine-containing polyolefin containing polytetrafluoroethylene is preferably used as the anti-drip agent.

[0042] The fluorinated polyolefins preferably used as anti-drip agents, which contain polytetrafluoroethylene, 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 3,671,487 A, 3,723,373 A and 3,838,092 A). They can be prepared by known processes, for example by polymerising tetrafluoroethylene in an aqueous medium with a free radical-forming catalyst, for example sodium, potassium or ammonium peroxydisulphate, 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.

[0043] Depending on the application, the density of the fluorinated polyolefins can be between 1.2 and 2.3 g / cm 3 ' preferably 2.0 to 2.3 g / cm 3 determined according to ISO 1183-1 (2019-09), the mean particle size zwiS between 0.05 and 1000 pm, determined by light microscopy or white light interferometry.

[0044] Suitable tetrafluoroethylene polymer powders are commercially available products and are offered, for example, by DuPont under the trade name Teflon®.

[0045] Polytetrafluoroethylene (PTFE), either as such or in the form of a PTFE-containing composition, is particularly preferred as a fluorine-containing anti-drip agent. If a PTFE-containing composition is used, its minimum usage amount is such that 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 PTFE encapsulated in SAN is particularly preferred as the fluorine-containing anti-drip agent.

[0046] Component C

[0047] 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.

[0048] Preferred phosphorus-containing flame retardants are cyclic phosphazenes, phosphorus compounds of formula (10) and mixtures thereof: where R 1 , R 2 , R 3 and R 4 independently of one another represent a C1- to C1x-alkyl radical, each optionally halogenated and each branched or unbranched, and / or C5- to C12-cycloalkyl radical, C12- to C20-aryl radical or C7- to C1n-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

[0049] 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.

[0050] 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 C1- to C1-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.

[0051] X in formula (10) is preferably derived from dihydroxyaryl compounds.

[0052] X in formula (10) particularly preferably represents

[0053] (Xi) (Xn)

[0054] (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.

[0055] As a phosphorus compound of the general formula (10), a compound of the formula (11) is preferred: wherein

[0056] R 1 , R 2 , R 3 and R4 each independently of one another represents a linear or branched C1- to C12-alkyl radical and / or optionally linear or branched alkyl-substituted C5- to C10-cycloalkyl radical, C12- to C12-aryl radical or C7- to C12-aralkyl radical, n independently of one another represents 0 or 1, q independently of one another represents 0, 1, 2, 3 or 4,

[0057] N is a number between 1 and 30,

[0058] R5 and Rs independently of one another are linear or branched Ci- to Cü-alkyl, preferably methyl, and

[0059] Y is linear or branched C1- to C12-alkylidene radical, a linear or branched C1- to C7-alkylene radical, a C5- to C12-cycloalkylene radical, a C5- to C12-cycloalkylidene radical, -O-, -S-, -SO-, SO2 or -CO-.

[0060] 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 when using phosphorus compounds of formula (10).

[0061] 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.

[0062] In this case, 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 particularly preferably contained in the compositions according to the invention.

[0063] 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).

[0064] Alternatively, cyclic phosphazenes according to formula (13) are particularly preferably used as component C:

[0065] (13), where

[0066] R is the same or different and for

[0067] - an amine residue,

[0068] - an optionally halogenated, preferably fluorine-halogenated, more preferably monohalogenated, Ci- to Cx-alkyl radical, preferably methyl, ethyl, propyl or butyl radical,

[0069] - a Ci to Cs alkoxy radical, preferably a methoxy radical, ethoxy radical, propoxy radical or butoxy radical,

[0070] - a C5- to C20-cycloalkyl radical, each optionally substituted by alkyl, preferably C1- to C4-alkyl, and / or halogen, preferably chlorine and / or bromine, - a C5- to C20-aryloxy radical, each optionally substituted by alkyl, preferably C1- to C4-alkyl, and / or halogen, preferably chlorine, bromine, and / or hydroxy-substituted, preferably phenoxy radical, naphthyloxy radical,

[0071] - a C7 to C12 aralkyl radical, preferably phenyl, which is optionally substituted by alkyl, preferably C1 to C4 alkyl, and / or halogen, preferably chlorine and / or bromine.

[0072] Ci- to C4-alkyl radical, or

[0073] - a halogen radical, preferably chlorine or fluorine, or

[0074] - 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.

[0075] Commercially available phosphazenes are preferred. These are usually mixtures of rings with different ring sizes.

[0076] Further preferred are, both individually and in mixtures: propoxyphosphazene, phenoxyphosphazene, methylphenoxyphosphazene, aminophosphazene, fluoroalkylphosphazenes and phosphazenes of the following structures:

[0077] 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.

[0078] 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.

[0079] In one embodiment, only phosphazenes with the same R are used.

[0080] 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%.

[0081] Preferably, the proportion of the higher oligomeric phosphazenes (k = 3, 4, 5, 6 and 7) is 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%.

[0082] Preferably, the proportion of oligomers with k > 8 is from 0 to 2.0 mol%, based on component B, and preferably from 0.10 to 1.00 mol%.

[0083] More preferably, the phosphazenes of component C fulfill all three of the above-mentioned conditions with regard to the proportions of oligomers.

[0084] 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.%.

[0085] 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.

[0086] 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).

[0087] The phosphazenes and their preparation are described, for example, in EP 728 811 A2, DE 1961668 A and WO 97 / 40092 A1.

[0088] The oligomer compositions in the respective blend samples can be determined after compounding using 31 Detect 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).

[0089] 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), extremely preferably component C is cyclic phosphazene according to formula (13).

[0090] The proportion of phosphorus-containing flame retardant in the compositions according to the invention is at least 2 wt.%, based on the total composition. If the phosphorus-containing flame retardant is an organophosphate, its amount in the composition, based on the total composition, is 2 to 12 wt.%, preferably 2 to 10 wt.%, particularly preferably 2 to 8 wt.%. With a lower proportion of organophosphate in the compositions, increasingly higher Vicat temperatures and thus higher heat distortion temperature can be achieved. If the phosphorus-containing flame retardant is a phosphazene, its amount in the composition, based on the total composition, is 2 to 9 wt.%, preferably 4 to 8 wt.%.

[0091] The ratio of phosphorus-containing flame retardant to PTFE, i.e. the quotient of the amount of component C, i.e. phosphorus-containing flame retardant, and the amount of PTFE, is < 40, preferably < 32.

[0092] Component D

[0093] The thermoplastic compositions Z may contain one or more further additives other than components B and C, which are summarized here under "component D." Optionally, other customary additives ("further additives") are present (0 wt.%), preferably up to 10 wt.%, even more preferably 0.1 wt.% to 5 wt.%, particularly preferably 0.1 wt.% to 3 wt.%, very particularly preferably 0.2 wt.% to 1.0 wt.%), wherein these percentages by weight are based on the total weight of the composition. The group of further additives does not include a fluorine-containing anti-drip agent according to component B or a phosphorus-containing flame retardant according to component C.

[0094] Such additional additives, which are usually added to polycarbonates, are in particular thermal stabilizers, antioxidants, mold release agents, UV absorbers, IR absorbers,

[0095] Impact modifiers, antistatic agents, flame retardants other than component C, optical brighteners, light scattering agents, hydrolysis stabilizers, transesterification stabilizers, (organic) dyes, (organic / inorganic) pigments, e.g., titanium dioxide, 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 in admixture and are preferred additives according to the invention.

[0096] Further preferred additives, if any further additives are present, are one or more further additives selected from the group consisting of thermal stabilizers, antioxidants, mold release agents, organic dyes, organic pigments, inorganic pigments, most preferably one or more antioxidants, thermal stabilizers and / or mold release agents.

[0097] It is understood that only such additives and only in such quantities may be added if they do not have a significantly negative effect on the inventive effect of the high CTI and preferably also the Vicat temperature, determined according to ISO 306:2014-3, VST Method B, is not reduced below 100°C, preferably not below 115°C.

[0098] The compositions according to the invention may contain other flame retardants in addition to component C, but are free from those selected from the group of alkali, alkaline earth, or ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide, and sulfonimide derivatives, and combinations thereof. "Derivatives" are understood to mean compounds whose molecular structure contains a different atom or group of atoms instead of an H atom or a functional group, or in which one or more atoms / groups of atoms have been removed. The parent compound is thus still recognizable.Such flame retardants which are not present in compositions according to the invention are, in particular, one or more compounds selected from the group consisting of sodium or potassium perfluorobutane sulfate, sodium or potassium perfluoromethanesulfonate, sodium or potassium perfluorooctane sulfate, sodium or potassium 2,5-dichlorobenzenesulfate, sodium or potassium 2,4,5-trichlorobenzenesulfate, sodium or potassium diphenylsulfonesulfonate, sodium or potassium 2-formylbenzenesulfonate, sodium or potassium (N-benzenesulfonyl)benzenesulfonamide or mixtures thereof, of which particularly preferably sodium or potassium perfluorobutane sulfate, sodium or potassium perfluorooctane sulfate, sodium or potassium diphenylsulfonesulfonate or mixtures thereof, in particular potassium perfluoro-1-butanesulfonate, which is commercially available, inter alia as Bayowet® C4 from Lanxess, Leverkusen, Germany. Very particularly preferably, no further flame retardants are present at all.

[0099] 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 0.02 to 0.60 wt.%, in each case based on the total composition.

[0100] Particularly preferred additives are also thermal stabilizers. The amount of thermal stabilizer is preferably up to 0.20 wt.%, more preferably 0.01 to 0.10 wt.%, even more preferably 0.01 to 0.05 wt.%, particularly preferably 0.015 to 0.040 wt.%, based on the total composition.

[0101] Phosphorus-based stabilizers selected from the group of phosphates, phosphites, phosphonites, phosphines and their mixtures are particularly suitable as thermal stabilizers. Examples are triphenyl phosphite, diphenyl alkyl phosphite, phenyl dialkyl phosphite, tris(nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearylpentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl phosphite (Irgafos® 168), Diisodecylpentaerythritol diphosphite, bis(2,4-di-tert-butylphenyljpentaerythritol 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)-pentaerythritol diphosphite, bis(2,4,6-tris(tert-butylphenyljpentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylenediphosphonite, 6-Isooctyloxy-2,4,8,10-tetra-tert-butyl-12H-dibenz[d,g]-l,3,2-dioxaphosphocin, Bis(2,4-di-tert-butyl-6-methylphenyl)methyl phosphite, bis(2,4-di-tert-butyl-6-methylphenyljethyl phosphite, 6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyl-dibenz[d,g]-1,3,2-dioxaphosphocin, 2,2',2"-Nitrilo-[triethyltris(3,3',5,5'-tetra-tert-butyl-l,l'-biphenyl-2,2'-diyl)phosphite], 2-ethylhexyl(3,3',5,5'-tetra-tert-butyl-l,l'-biphenyl-2,2'-diyl)phosphite, 5-Butyl-5-ethyl-2-(2,4,6-tri-tert-butylphenoxy)-1,3 ,2-dioxaphosphiran, bis(2,6-di-ter-butyl-4-methylphenyl)pentaerythritol diphosphite, triphenylphosphine (TPP), trialkylphenylphosphine, bisdiphenylphosphinoethane, or trinaphthylphosphine. They are used alone or in a mixture with thermal stabilizers or antioxidants, e.g., Irganox® B900 (a mixture of Irgafos® 168 and Irganox® 1076 in a ratio of 4:1) or Doverphos® S-9228 with Irganox® B900 or Irganox® 1076. Triphenylphosphine (TPP), Irgafos® 168, or tris(nonylphenyl)phosphite, or mixtures thereof, are particularly preferred.

[0102] 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 0.02-0.5 wt.%.

[0103] 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.

[0104] Examples of impact modifiers include: 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 Metablen® grades 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.

[0105] The thermoplastic composition Z, containing the mixed components A, B, C, and optionally D, can be produced 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 D and also other constituents of the thermoplastic compositions can be introduced by known methods or as a masterbatch. The use of masterbatches is particularly preferred for introducing additives and other constituents, with particular use of masterbatches based on the respective polymer matrix.

[0106] The thermoplastic compositions Z can, for example, be extruded. After extrusion, the extrudate can be cooled and comminuted. The melt can also be combined and thoroughly mixed in the plasticizing unit of an injection molding machine. In this case, the melt is transferred directly into a molded body in the subsequent step.

[0107] The invention also relates to the use of the combination of 0.25 wt.% to 5 wt.% fluorine-containing anti-drip agent containing polytetrafluoroethylene, at least 2 wt.% phosphorus-containing flame retardant, wherein the ratio of phosphorus-containing flame retardant to PTFE is < 40, preferably < 32 and wherein, if the phosphorus-containing flame retardant b1) is an organophosphate, the amount of phosphorus-containing flame retardant is 2 to 12 wt.% and if the phosphorus-containing flame retardant b2) is a phosphazene, the amount of phosphorus-containing flame retardant is 2 to 9 wt.%, for achieving a CTI, determined in accordance with IEC 60112:2009, of 600 V of a composition based on aromatic polycarbonate, wherein the stated amounts relate to the resulting total composition.

[0108] It is understood that the embodiments described above as preferred etc. for the thermoplastic composition Z also apply analogously to the use according to the invention.

[0109] Various embodiments of the present invention are described below:

[0110] 1. 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 Z that 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 material M 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, 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 and wherein the thermoplastic composition Z comprises the following components:,

[0111] A) at least 80% by weight of aromatic polycarbonate based on bisphenol A,

[0112] B) 0.25 wt.% to 5 wt.% fluorine-containing anti-drip agent containing polytetrafluoroethylene,

[0113] C) at least 2% by weight of phosphorus-containing flame retardant, the quotient of the amount of phosphorus-containing flame retardant and the

[0114] Amount of polytetrafluoroethylene is < 40, preferably < 32 and wherein, when the phosphorus-containing flame retardant b1) is an organophosphate, the amount of phosphorus-containing flame retardant is 2 to 12 wt.% and when the phosphorus-containing flame retardant b2) is a phosphazene, the amount of phosphorus-containing flame retardant is 2 to 9 wt.% and wherein the thermoplastic composition Z is free of flame retardants selected from the group of alkali metal, alkaline earth metal and ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide or sulfonimide derivatives.

[0115] 2. EE component according to embodiment 1, wherein the phosphorus-containing flame retardant is a phosphazene or a mixture of different phosphazenes.

[0116] 3. EE component according to embodiment 1, wherein the phosphorus-containing flame retardant comprises a cyclic phosphazene and / or a phosphorus compound of formula (10).

[0117] 4. EE component according to embodiment 1, wherein the phosphorus-containing flame retardant is a cyclic phosphazene and / or a phosphorus compound of formula (10)

[0118] (10), wherein

[0119] R 1 , R 2 , R 3 and R 4 independently of one another represent a C 1 - to C 1x -alkyl radical, in each case optionally halogenated and in each case branched or unbranched, and / or C 5 - to C 10 -cycloalkyl radical, C 1 - to C 20 -aryl radical or C 7 - to C 1n -aralkyl radical, in each case optionally substituted by branched or unbranched alkyl and / or halogen, preferably chlorine and / or bromine, n independently of one another represent 0 or 1, q represents a value from 0 to 30 and 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, which may in each case be substituted or unsubstituted, bridged or unbridged.

[0120] 5. EE component according to embodiment 1 or 3, wherein the phosphorus-containing flame retardant is a

[0121] Organophosphate of formula (11) wherein

[0122] 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, C1- to C10-aryl radical or C7- to C12-aralkyl radical, n independently of one another is 0 or 1, q independently of one another is 0, 1, 2, 3 or 4,

[0123] N is a number between 1 and 30,

[0124] R5 and Rs independently of one another are linear or branched Ci- to C-alkyl, preferably methyl, and

[0125] Y is a linear or branched C1- to C12-alkylidene radical, a linear or branched C1- to C7-alkylene radical, a C5- to C12-cycloalkylene radical, a C5- to C12-cycloalkylidene radical, -O-, -S-, -SO-, SO2 or -CO-, or a

[0126] Phosphazene of the formula (13g) with k = 1, 2 or 3 EE component according to embodiment 1, 3 or 4, wherein the cyclic phosphazene is a phosphazene of

[0127] Formula (13) is where

[0128] R is the same or different and for

[0129] - an amine residue,

[0130] - an optionally halogenated, preferably fluorine-halogenated, more preferably monohalogenated, Ci- to Cx-alkoxy, preferably methyl, ethyl, propyl or butyl radical,

[0131] - a Ci to Cs alkoxy radical, preferably a methoxy radical, ethoxy radical, propoxy radical or butoxy radical,

[0132] - a C5- to C12-cycloalkyl radical optionally substituted by alkyl, preferably C1- to C4-alkyl, and / or halogen, preferably chlorine and / or bromine,

[0133] - a Ce- to C2o-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,

[0134] - a C7- to C12-aralkyl radical, each optionally substituted by alkyl, preferably C1- to C4-alkyl, and / or halogen, preferably chlorine and / or bromine, preferably phenyl-C1- to C4-alkyl radical, or

[0135] - a halogen radical, preferably chlorine or fluorine, or

[0136] - 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 preferably 1. 7. EE component according to embodiment 3 or 4, wherein the phosphorus compound of formula (10) is a bisphenol A-based oligophosphate of formula (12) with q = 1 to 20, in particular with q = 1.0 to 1.2.

[0137] 8. EE component according to one of the embodiments 1 to 7, wherein a degree of protection IP6K9K according to ISO 20653:2013-02 is present.

[0138] 9. EE component according to one of the embodiments 1 to 8, where d2 > 1.2 mm.

[0139] 10. EE component according to one of the preceding embodiments, wherein the aromatic polycarbonate is bisphenol A-based homopolycarbonate.

[0140] 11. EE component according to one of the preceding embodiments, wherein the thermoplastic composition Z further contains:

[0141] D) one or more additives selected from the group consisting of mold release agents, thermal stabilizers, antioxidants, dyes, impact modifiers, pigments, UV absorbers, IR absorbers, optical brighteners, hydrolysis stabilizers, transesterification stabilizers, compatibilizers, additives for laser marking, flow improvers and mixtures thereof.

[0142] 12. EE component according to one of embodiments 1 to 10, wherein the thermoplastic composition Z further contains: one or more additives selected from the group consisting of mold release agents, thermal stabilizers, antioxidants, dyes, pigments, transesterification stabilizers, flow improvers and mixtures thereof.

[0143] 13. EE component according to any of the preceding embodiments, wherein the thermoplastic composition contains no further constituents. 14. EE component according to any of embodiments 1 to 4, 6, 8 to 13, wherein the phosphorus-containing flame retardant is a phosphazene and its amount is 4 to 8 wt.% of the total composition.

[0144] 15. EE component according to one of embodiments 1, 3 to 5, 7 to 13, wherein the phosphorus-containing flame retardant is an organophosphate and its amount is 2 to 10 wt.% of the total composition.

[0145] 16. EE component according to any one of the preceding embodiments, wherein the EE component is part of a high-voltage switch, inverter, relay, electronic connector, electrical connector, circuit breaker, photovoltaic system, electric motor, heat sink, charger or charging plug for electric vehicles, electrical junction box, smart meter housing, miniature circuit breaker, or power busbar.

[0146] 17. EE component according to one of the preceding embodiments, wherein 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.

[0147] 18. EE component according to one of the preceding embodiments, wherein the EE component is designed for an operating voltage of at least 400 V.

[0148] 19. EE component according to one of the preceding embodiments, wherein the thermoplastic composition Z contains, in addition to components A, B and C, as component D only one or more thermal stabilizers, antioxidants, mold release agents, dyes, pigments and mixtures thereof.

[0149] 20. EE component according to one of the preceding embodiments, wherein the thermoplastic composition Z has a CTI of 600 V, determined in accordance with IEC 60112:2009.

[0150] 21. EE assembly comprising an EE component according to one of the preceding embodiments, wherein the EE assembly has a protection class IP6K9K according to ISO 20653:2013-02.

[0151] 22. EE module, where the operating voltage of the EE module is at least 400 V.

[0152] 23. EE assembly according to one of embodiments 21 or 22, which belongs to the field of electromobility. Use of a thermoplastic composition as defined as part of any of embodiments 1 to 15 to achieve a CTI, determined in accordance with IEC 60112:2009, of 600 V in an aromatic polycarbonate-based composition containing at least 80 wt. % aromatic polycarbonate based on bisphenol A, wherein the stated amount refers to the resulting total composition. Use according to embodiment 24, wherein the aromatic polycarbonate is a bisphenol A-based homopolycarbonate.

[0153] Examples

[0154] 1. Description of raw materials and test methods a) Raw materials

[0155] 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 D-3 250 ppm (= 0.025 wt.%, based on the total weight of component A) thermal stabilizer triphenylphosphine.

[0156] 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).

[0157] Component Bl: SAN-encapsulated polytetrafluoroethylene ADS5000 (approx. 50 wt.% PTFE (fluorine-containing anti-drip agent) and approx. 50 wt.% SAN) from Chemical Innovation Co., Ltd. Thailand.

[0158] Component B-2: Fluorine-containing anti-drip agent. Polytetrafluoroethylene Teflon CFP6000X from Chemours Netherlands BV

[0159] Component Cl: Organophosphate of formula (12) with q = 1.0 - 1.2. Bisphenol A bis(diphenyl phosphate) from Adeka.

[0160] Component C-2: Phenoxycyclophosphazene Rabitle FP110 from Fushimi Pharmaceutical, Japan, formula (13g), with a trimer content (k = 1) of about 68 mol%.

[0161] Component Cx: Potassium perfluoro-1-butanesulfonate, commercially available as Bayowet® C4 from Lanxess AG, Leverkusen, Germany, CAS No. 29420-49-3.

[0162] Component D1: Mold release agent. Pentaerythritol tetrastearate, commercially available as Loxiol VPG 861 from Emery Oleochemicals Group.

[0163] Component D-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

[0164] Comparative tracking index (CTI):

[0165] 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 maximum voltage determined 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.

[0166] Flame resistance:

[0167] The flame retardancy test of the polycarbonate compositions was conducted according to Underwriters Laboratory Method UL 94 V in 2 mm thicknesses. The tested test specimens were previously conditioned for 7 days at 20% relative humidity and 70°C ambient temperature.

[0168] Different fire classes are assigned based 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 V0, VI, and V2 and are determined based on a total of five tested specimens.

[0169] VO: 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.

[0170] 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.

[0171] 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.

[0172] Heat resistance:

[0173] 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.

[0174] 2. Preparation of the test specimens

[0175] 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.

[0176] The test specimens with dimensions of 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.

[0177] Results

[0178] In the following tables, "ng" means "not tested." The notation "*" means "taken from UL Yellow Card."

[0179] Table 1

[0180] Table 2

[0181] The examples summarized in Tables 1 and 2 include compositions of polycarbonate, anti-drip agent (PTFE / SAN), and flame retardant, as well as other additives. Adding small amounts of a phosphorus-based flame retardant such as BDP together with PTFE can achieve a CTI of 600 V and a VO classification with thin wall thicknesses, which represents an attractive property package for the aforementioned applications (see E-3 to E-13). The flame retardant alone does not improve the CTI compared to a non-FR polycarbonate composition (compare E-5 with E-2). Larger amounts of flame retardant must be balanced by larger amounts of anti-drip agent to achieve the CTI of 600 V (compare E-13 with E-8). The further results in Table 2 include compositions with phosphazene as flame retardant (see E-14 - E-17), which also achieve a high CTI and a VO classification.Furthermore, corresponding compositions with pure PTFE instead of a PTFE / SAN masterbatch are listed, which also achieve a CTI of 600 V and a V0 based on the total PTFE content of the compositions (see E-19 to E-22). Finally, Comparative Examples V-23 to V-26 demonstrate that inorganic flame retardants based on, for example, alkyl sulfonates do not lead to high tracking resistance.

Claims

1. An electrical component comprising a first electrical conductor and a second electrical conductor separated by a first distance dl and a second distance d2, which are connected via a thermoplastic composition Z in direct contact with the first and second electrical conductors, wherein the distance dl is the shortest distance between the first and second electrical conductors along the surface of the thermoplastic material M, and wherein the distance d2 is the shortest distance between the first and second electrical conductors through air, where d2 is selected to prevent arcing through air at the respective operating voltage, wherein dl is, at the following operating voltages U: dli(0V < U < 250V): 1.3 mm to < 2.5 mm; dlii(250V < U < 500V): 2.5 mm to < 5.0 mm; dlii(500V < U < 1000V): 5.0 mm to < 10.00 mm.0 mm and wherein the thermoplastic composition Z comprises the following components:, A) at least 80% by weight aromatic polycarbonate, based on bisphenol A, B) 0.25 wt.% to 5 wt.% fluorinated anti-drip agent containing polytetrafluoroethylene, C) at least 2 wt.% phosphorus-containing flame retardant, wherein the ratio of the amount of phosphorus-containing flame retardant to the amount of polytetrafluoroethylene is < 40, and wherein, if the phosphorus-containing flame retardant b) is an organophosphate, the amount of phosphorus-containing flame retardant is 2 to 12 wt.%, and if the phosphorus-containing flame retardant b2) is a phosphazene, the amount of phosphorus-containing flame retardant is 2 to 9 wt.%, and wherein the thermoplastic composition Z is free of flame retardants selected from the group of alkali, alkaline earth and ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide or sulfonimide derivatives.

2. EE component according to claim 1, wherein the phosphorus-containing flame retardant is an organophosphate of formula (11) wonn R 1 , R 2 , R 3 and R 4each independently a linear or branched Ci to Cs alkyl group and / or optionally by linear or branched alkyl-substituted C5 to Cö 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, R5 and R5 independently linear or branched Ci to C'x alkyl groups, preferably methyl groups, and Y linear or branched Ci- to CS-alkylide group. a linear or branched Ci- to CS-alkyl group. C5- to Ci2-cycloalkylene residue, C5- to Ci2-cycloalkylidene residue, -O-, -S-, -SO-, SO2- or -CO- mean, or a Phosphazene of formula (13g) EE component according to claim 1 or 2, wherein the aromatic polycarbonate is bisphenol A-based homopolycarbonate. EE component according to any one of the preceding claims, wherein the thermoplastic composition further comprises: D) one or more additives selected from the group consisting of release agents, heat stabilizers, antioxidants, colourants, Impact modifiers, pigments, UV absorbers, IR absorbers, optical brighteners, hydrolysis stabilizers, transection stabilizers, Compatibility improvers, laser marking additives, flow improvers and their mixtures.

5. EE component according to one of claims 1 to 4, wherein the thermoplastic composition Z contains, in addition to components A, B and C, as component D only one or more thermostabilizers, antioxidants, demolding agents, dyes, pigments and mixtures thereof.

6. EE component according to one of the preceding claims, wherein the EE component is part of a high-voltage switch, inverter, relay, electronic connector, electrical connector, circuit breaker, photovoltaic system, electric motor, heat sink, charger or charging plug for electric vehicles, electrical junction box, smart meter housing, miniature disconnect switch, or busbar.

7. EE component according to one of the preceding claims, wherein 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.

8. EE component according to one of the preceding claims, wherein the EE component is designed for an operating voltage of at least 400 V.

9. EE component according to one of the preceding claims, wherein the thermoplastic composition contains no further components.

10. EE component according to one of the preceding claims, wherein the thermoplastic composition Z contains 4 to 8 wt.% cyclophosphazene.

11. EE assembly comprising an EE component according to one of the preceding claims, wherein the EE assembly has a protection class IP6K9K according to ISO 20653:2013-02.

12. EE assembly according to claim 11, wherein the operating voltage of the EE assembly is at least 400 V. Use of the combination of 0.25 wt.% to 5 wt.% fluorinated anti-drip agent containing polytetrafluoroethylene, at least 2 wt.% phosphorus-containing flame retardant, wherein the ratio of phosphorus-containing flame retardant to PTFE is < 40, and wherein, if the phosphorus-containing flame retardant b) is an organophosphate, the amount of phosphorus-containing flame retardant is 2 to 12 wt.%, and if the phosphorus-containing flame retardant b2) is a phosphazene, the amount of phosphorus-containing flame retardant is 2 to 9 wt.%, to achieve a CTI, determined in accordance with IEC 60112:2009, of 600 V of an aromatic polycarbonate-based composition containing at least 80 wt.% aromatic polycarbonate based on bisphenol A, wherein the specified amounts refer to the resulting total composition.

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