EE devices containing composite polycarbonate elements with high CTI

Abstract

The present invention relates to an EE device in which the distance range between the conductors varies depending on the applied working voltage, and the distance is so small that the material used between the conductors already results in a very high comparative tracking index. Surprisingly, this material is a polycarbonate-based material, and its comparative tracking index increases significantly when a relatively small amount of a fluorine-containing anti-drip agent and a phosphorus-based flame retardant is added.

Description

[Technical field]

[0001] The present invention relates to EE components made from polymeric materials with high tracking current resistance. [Background technology]

[0002] In applications where plastics are in direct contact with conductor tracks, a high resistance to tracking currents under voltage load is a prerequisite to ensure that there are no short circuits in the component and therefore no fires. Comparative Tracking Index (CTI) generally describes the resistance of plastic materials to environmental influences. The CTI value is a measure of the tendency of plastics to form conductive paths on the surface under voltage and promote the generation of electrical tracking currents under the influence of environmental influences, such as moisture and pollution. The higher the tracking current resistance of a material, i.e. the higher its Comparative Tracking Index (CTI value), the better it is suitable for use in high voltage applications, such as modern electromobility applications. Another advantage of materials with high CTI values ​​is that it is possible to place conductor tracks close together in EE components without risk of short circuits, which in turn allows for a reduction in component dimensions and therefore a more compact design and weight reduction.

[0003] Polycarbonate is of fundamental interest as a polymeric material, for example due to its high impact resistance and high thermal distortion resistance, but due to its inherently low tracking current resistance it has not been considered for such applications. In contrast to other thermoplastic polymers, such as polystyrene, polyesters, etc., polycarbonate has a very low comparative tracking index by itself. Due to the high proportion of aromatic structures, polycarbonate has a relatively high tendency to char. The CTI of pure polycarbonate is about 250 V or even lower (Non-Patent Document 1).

[0004] For many applications in the electronic / electrical sector (EE), for example in the field of electromobility, a relatively high CTI is required for the materials used solely for safety reasons. This is because, for example, housings made of certain materials, in the case of, for example, a collision in an accident, can dent and come into contact with electrical conductors, resulting in a bridge between them. In such cases, it is necessary to prevent short circuits as much as possible. Other applications are essentially carried out at voltages of 400 V and above, so that materials with a correspondingly high tracking current resistance are required. In the field of E-mobility, for example due to the need for fast charging times, the current standard is already a working voltage of 400 V, with further increases expected. Polycarbonate has therefore not been considered so far as a material for many applications that particularly require a high comparative tracking index of the material.

[0005] The higher the tracking current resistance of a material, the smaller the distance between the conductors of an EE component can be depending on the applied working voltage. This is important, for example, in the case of a battery, since even a fraction of a millimeter reduction in the distance between two conductors significantly increases the capacity or energy density of the battery. At the same time, it is desirable to use otherwise attractive polycarbonates for corresponding EE applications.

[0006] The problem addressed was therefore to provide EE parts in which electrical conductors are connected with a polycarbonate material having a high CTI, preferably determined by a rapid test method according to IEC 60112:2009, of at least 400 V, preferably 600 V. Because of the field of application and the heat development in the EE parts, the thermoplastic compositions used should preferably also have good heat distortion 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. [Prior art documents] [Non-patent literature]

[0007] [Non-Patent Document 1] F. Acquasanta et al., Polymer Degradation and Stability, 96 (2011), 2098-2103 Summary of the Invention

[0008] Surprisingly, it has been found that polycarbonate-based compositions containing bisphenol A-based polycarbonate, fluorine-containing anti-drip agent, and phosphorus-containing flame retardant in specific amounts have very high tracking current resistance, and these polycarbonate compositions can be used to make it possible to shorten the distance between two conductors of a part than was previously thought possible when using polycarbonate.This was particularly surprising because polycarbonate has an inherently low tracking current resistance and the amount of additive added is relatively low compared to the polycarbonate content of the resulting composition.

[0009] Thus, the present invention provides an EE component, comprising: a first conductor and a second conductor at a first distance d1 and a second distance d2 from each other; Including, They are connected via a thermoplastic composition Z, which is in direct contact with the first and second electrical conductors; distance d1 is the shortest distance between the first and second conductors along the surface of the thermoplastic material M; The distance d2 is the shortest distance through air between the first conductor and the second conductor, and d2 is selected to prevent sparks through air at each operating voltage; d1 is the following at the working voltage U listed below: d1i(0V≦U≦250V):1.3mm~<2.5mm d1ii(250V <U≦500V)=2.5mm~<5.0mm d1iii(500V <U≦1000V)=5.0mm~<10.0mm and the thermoplastic composition Z comprises the following components: A) at least 80% by weight of an aromatic polycarbonate based on bisphenol A; B) 0.25% by weight to 5% by weight of a fluorine-containing drip prevention agent containing polytetrafluoroethylene; C) at least 2% by weight of a phosphorus-containing flame retardant; wherein the quotient of the amount of the phosphorus-containing flame retardant and the amount of PTFE is 40 or less; The phosphorus-containing flame retardant b1) organic phosphate esters, In this case, the amount of the phosphorus-containing flame retardant is 2% by weight to 12% by weight; The phosphorus-containing flame retardant b2) phosphazenes, In this case, the amount of the phosphorus-containing flame retardant is 2% by weight to 9% by weight; Thermoplastic composition Z provides EE parts that are free of flame retardants selected from the group of alkali metal, alkaline earth metal or ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide or sulfonimide derivatives.

[0010] Such small lower limits on the distance between conductors are achievable only with materials that have a CTI of at least 600 V. Even the upper limits of these small separation ranges can only be achieved if the materials used have a CTI of at least 400 V.

[0011] For this reason, the separation ranges detailed below are only achievable at the specified working voltages if the material has a CTI of at least 400V: d1i(0V≦U≦250V):1.8mm~<2.5mm d1ii(250V <U≦500V)=3.6mm~<5.0mm d1iii(500V <U≦1000V)=7.1mm~<10.0mm。

[0012] More preferably, when a material having a CTI of 600V is used as described as part of the present invention, d1 at the stated working voltage is as follows: d1i(0V≦U≦250V):1.3mm~<1.8mm, d1ii(250V <U≦500V)=2.5mm~<3.6mm、 d1iii(500V <U≦1000V)=5.0mm~<7.1mm、 , which are distances that are not achievable even with materials with a CTI of 400V or 450V, and require a CTI of 600V.

[0013] Because of this, it is possible to achieve EE components using polycarbonate materials between two conductors with smaller distances than previously thought possible.

[0014] The selection of d2 is within the ability of one skilled in the art. Preferably, d2 is at least 1.2 mm.

[0015] It is known that the degree of contamination affects the electrical conductivity. The mentioned distances d1 and d2 are of practical use, for example, in components to which a protection of IP6K9K according to ISO 20653:2013-02 is bonded due to structural screening.

[0016] The thermoplastic compositions used in the EE components of the present invention have the advantage that, due to their high tracking current resistance, they can be assigned to insulation group II (400 V≦CTI<600 V), particularly preferably insulation group I (600 V≦CTI), as classified according to DIN EN 60664-1.

[0017] Due to the high tracking current resistance of the materials used, the EE components of the invention are preferably used in EE assemblies designed for working voltages of at least 400 V, possibly even 600 V. Corresponding EE assemblies therefore also form part of the subject matter of the present invention.

[0018] The EE component of the present invention is preferably part of a high voltage switch, inverter, relay, electronic connector, electrical connector, circuit breaker, photovoltaic system, electric motor, heat sink, electric vehicle charger or charging plug, electrical junction box, smart meter housing, miniature circuit breaker, busbar, etc. "Part of" here means that it may be an individual element of a complex product, a group of parts, but also the whole element, for example in the case of "electronic connector".

[0019] The thermoplastic composition Z used in the EE part of the present invention necessarily comprises component A, component B, and component C. Optionally, further components, such as additives according to component D, can be added as long as they do not adversely affect the desired effect of high tracking current resistance.

[0020] The invention also provides the use of the corresponding compositions to achieve a CTI of at least 600 V. It is clear that the preferred, more preferred, particularly preferred etc. embodiments described for the EE parts, possibly also relating to the aspect of the thermoplastic composition Z, are also applicable to the use of the present invention.

[0021] Such a specific use also exists, for example, when the corresponding composition Z is used for an insulating layer that requires a CTI of 600V for the application. Such an insulating layer can be provided, for example, on an inverter as a layer for protection against external influences. For inverters, the standard insulating material has a CTI of 600V. The composition according to the invention can also be used as an insulating layer for other electrical components, for example transistors. The electrical components of the transistor are protected by overmolding a plastic with a high CTI. This plastic protects the electrical components both from contact and from undesired electrical interaction with adjacent metal parts or electrical components, such as metal heat sinks.

[0022] Another reason why transistors are often mounted directly on a heat sink is because of the high heat they generate during operation. Here again, the thermoplastic composition Z introduced between the heat sink and the transistor ensures safe operation.

[0023] A further field of use is mounting brackets for busbars, where again it is necessary to use materials with a high CTI. The mounting brackets essentially have two functions: fixing the busbars in a component group to prevent any position changes during operation, and acting as a spacer to allow several busbars to be juxtaposed, where again it is necessary to choose a sufficiently large distance between two busbars to prevent sparks through the air. However, in addition, it is necessary to prevent tracking on the surface of the mounting bracket, not only between the busbars, but also between the busbars and other metal parts, for example the screws for fixing the mounting bracket to the structure below. Mounting brackets with a high CTI can increase the component density and energy density here.

[0024] For plug connectors, plug devices, and sockets, there is a high risk of tracking currents occurring, which can lead to electrical failures and possible fires. Enclosures that enclose the current-carrying wires can improve the situation, as they have a lower risk of contamination. Plug connectors for charging devices, or USB-C plug connectors, are at higher risk, as they cannot cover or seal the current-carrying conductor paths, and are further exposed to contamination such as sweat, moisture, fabric particles, dust, and other materials. High CTI materials are needed to provide sufficient protection from tracking, but also to allow for miniaturization or increased power density.

[0025] The ingredients mentioned in the compositions used according to the present invention are explained in detail hereinafter.

[0026] Ingredient A Component A of the thermoplastic composition of the present invention is a polycarbonate based on bisphenol A. Preferably, "bisphenol A-based" means that the polycarbonate contains at least 50% by weight, more preferably at least 70% by weight, and even more preferably at least 90% by weight, of monomeric units based on bisphenol A.

[0027] Component A is preferably a bisphenol A homopolycarbonate, ie an aromatic polycarbonate whose only monomeric units are based on bisphenol A.

[0028] The melt volume-flow rate MVR of the aromatic bisphenol A homopolycarbonate used, specified according to ISO 1133:2012-03 at a test temperature of 300°C and a load of 1.2 kg, is preferably 5 cm 3 / (10 minutes)~35cm 3 / (10 min), more preferably 6 cm 3 / (10 minutes)~21cm 3 / (10 min), particularly preferably 10 cm 3 / (10 minutes)~19cm 3 / (10 min), especially preferred 11 cm 3 / (10 minutes)~15cm 3 / (10 min). If a different polycarbonate is used, these values ​​are based on a mixture of bisphenol A homopolycarbonate.

[0029] The details of polycarbonate preparation have been described in numerous patent specifications over the past 40 years or so. In this specification, the following may be mentioned by way of example: Schnell, "Chemistry and Physics of Polycarbonates", Polymer Reviews, Volume 9, Interscience Publishers, New York, London, Sydney 1964, D. Freitag, U. Grigo, PR Mueller, 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 Mueller "Polycarbonate" [Polycarbonates] in Becker / Braun, Kunststoff-Handbuch [Plastics Handbook], volume 3 / 1, Polycarbonate, Polyacetale, Polyester, Celluloseester [Polycarbonates, Polyacetals, Polyesters, Cellulose Esters], Carl Hanser Verlag Munich, Vienna 1992, pages 117 to 299.

[0030] Aromatic polycarbonates are prepared, for example, by the interfacial process, by reaction of dihydroxyaryl compounds with carbonyl halides, preferably phosgene, and / or aromatic dicarbonyl dihalides, preferably benzene dicarbonyl dihalides, optionally using chain terminators and optionally using trifunctional or higher branching agents. Also possible is the preparation by reaction of dihydroxyaryl compounds with, for example, diphenyl carbonate, via a melt polymerization process.

[0031] In the case of bisphenol A homopolycarbonate, only bisphenol A is used as the dihydroxyaryl compound.

[0032] In the preparation of bisphenol A homopolycarbonates, suitable chain terminators are one or more linear or branched, preferably unsubstituted C1-C 30 -alkyl radicals, or phenols with substitution by tert-butyl. Particularly suitable chain terminators are phenol, cumylphenol, and / or p-tert-butylphenol. The amount of chain terminator used is preferably 0.1 mol% to 5 mol%, based on the moles of dihydroxyaryl compound used in each case. The chain terminator may be added before, during or after the reaction with the carbonic acid derivative.

[0033] In principle, the homopolycarbonates may also be branched.

[0034] Suitable branching agents are trifunctional or higher compounds known in polycarbonate chemistry, especially those having three or more phenolic OH groups.

[0035] Examples of suitable branching agents include 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'-methylbenzyl)-4-methylphenol, 2-(4-hydroxyphenyl)-2-(2,4-dihydroxyphenyl)propane, tetra(4-hydroxyphenyl)methane, tetra(4-(4-hydroxyphenylisopropyl)phenoxy)methane, and 1,4-bis((4',4''-dihydroxytriphenyl)methyl)benzene, and 3,3-bis(3-methyl-4-hydroxyphenyl)-2-oxo-2,3-dihydroindole.

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

[0037] The branching agent may be initially charged with the bisphenol A and the chain terminator in the aqueous alkaline phase or may be added as a solution in an organic solvent prior to phosgenation. In the case of the transesterification process, the branching agent is used together with the bisphenol A.

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

[0039] Component B The thermoplastic composition Z contains a fluorine-containing anti-drip agent containing polytetrafluoroethylene (PTFE) as component B, which may be a mixture of two or more kinds of anti-drip agents. The total amount of the anti-drip agent (anti-drip agent) is 0.25% by weight to 5% by weight, preferably 0.4% by weight to 1.6% by weight, and particularly preferably 0.045% by weight to 1.0% by weight of at least one anti-drip agent.

[0040] The anti-drip agent used is preferably a fluorine-containing polyolefin, including polytetrafluoroethylene.

[0041] The fluorinated polyolefins preferentially used as anti-drip agents containing polytetrafluoroethylene have a high molecular weight, a glass transition temperature above -30°C, generally above 100°C, and a fluorine content preferably between 65% and 76% by weight, in particular between 70% and 76% by weight. Suitable fluorinated polyolefins are polytetrafluoroethylene, polyvinylidene fluoride, tetrafluoroethylene / hexafluoropropylene copolymers, and ethylene / tetrafluoroethylene copolymers. Fluorinated polyolefins are known ("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; "Modern Plastics Encyclopedia", 1970-1971, volume 47, No. 10 A, October 1970, McGraw-Hill, Inc., New York, pages 134 and 774; "Modern Plastics Encyclopedia", 1975-1976, October 1975, volume 52, No. 10 A, McGraw-Hill, Inc., New York, pages 27, 28 and (See U.S. Pat. Nos. 3,671,487, 3,723,373, and 3,838,092.) These can be prepared by known methods, for example, in an aqueous medium using a free radical forming catalyst (e.g., sodium peroxodisulfate, potassium peroxodisulfate, or ammonium peroxodisulfate, etc.) at a pressure of 7 kg / cm. 2 ~71kg / cm 2 and polymerizing tetrafluoroethylene at a temperature between 0° C. and 200° C., preferably between 20° C. and 100° C. Further details can be obtained, for example, in US Pat. No. 2,393,967.

[0042] Depending on the application, the density of the fluorinated polyolefins is specified according to ISO 1183-1 (2019-09) to be 1.2 g / cm 3 ~2.3g / cm 3 , preferably 2.0 g / cm 3 ~2.3g / cm 3 The average particle size may be 0.05 μm to 1000 μm as determined by optical microscopy or white light interferometry.

[0043] Suitable tetrafluoroethylene polymer powders are commercially available, for example, from DuPont under the trade name Teflon™.

[0044] Thus, the use of polytetrafluoroethylene (PTFE) is particularly preferred, but also in the form of a PTFE-containing composition is used as the fluorine-containing anti-drip agent. When a PTFE-containing composition is used, the minimum amount of PTFE present in the entire composition is sufficient if it is at least 0.25% by weight. The PTFE-containing composition includes Hostaflon™ TF2021 or a PTFE blend, such as Blendex™ B449 (about 50% by weight PTFE and about 50% by weight SAN (derived from 80% by weight styrene and 20% by weight acrylonitrile)) manufactured by Chemtura. Particular preference is given to using PTFE or SAN-encapsulated PTFE as the fluorine-containing anti-drip agent.

[0045] Component C Component C of the composition according to the invention is a phosphorus-containing flame retardant, which may be a single phosphorus-containing flame retardant or a mixture of different phosphorus-containing flame retardants.

[0046] Suitable phosphorus-containing flame retardants are cyclic phosphazenes, phosphorus compounds of formula (10), and mixtures thereof: [ka] During the ceremony, R 1 , R 2 , R3 , and R 4 are independently a C1-C8-alkyl radical, which in each case is optionally halogenated, in each case branched or unbranched, and / or a C5-C6-cycloalkyl radical, a C6-C 20 -aryl radical, or C7-C 12 - aralkyl radicals, which in each case are optionally substituted by branched or unbranched alkyl and / or halogen, preferably chlorine and / or bromine, n is independently 0 or 1; q is a value between 0 and 30; X is a monocyclic or polycyclic aromatic radical having 6 to 30 carbon atoms, or a straight or branched chain aliphatic radical having 2 to 30 carbon atoms, each of which can be substituted or unsubstituted and bridged or non-bridged.

[0047] Preferably, R 1 , R 2 , R 3 , and R 4 is independently branched or unbranched C1-C4-alkyl, phenyl, naphthyl, or C1-C4-alkyl substituted phenyl. 1 , R 2 , R 3 , and / or R 4 If they are radicals, these in turn can be substituted by halogens and / or alkyl groups, preferably chlorine, bromine and / or branched or unbranched C1-C4-alkyl. Particularly suitable aryl radicals are those corresponding to cresyl, phenyl, xylenyl, propylphenyl or butylphenyl, and their brominated and chlorinated derivatives.

[0048] X in formula (10) is preferably derived from a dihydroxyaryl compound.

[0049] X in formula (10) is particularly preferably the following: [ka] or their chlorinated and / or brominated derivatives. X (together with the adjacent oxygen atom) is preferably derived from hydroquinone, bisphenol A or diphenylphenol. It is likewise suitable that X is derived from resorcinol. Particularly preferably, X is derived from bisphenol A. n in formula (10) is preferably equal to 1. q is preferably 0 to 20, particularly preferably 0 to 10, and in the case of mixtures has an average value of 0.8 to 5.0, preferably 1.0 to 3.0, further preferably 1.05 to 2.00, particularly preferably 1.08 to 1.60.

[0050] The phosphorus compound of the general formula (10) is preferably a compound of the formula (11), [ka] During the ceremony, R 1 , R 2 , R 3 , and R 4 are each independently a linear or branched C1-C8 alkyl radical and / or optionally a linear or branched alkyl substituted C5-C6 cycloalkyl radical, C6-C 10 -aryl radical, or C7-C 12 -aralkyl radical, n is independently 0 or 1; q is independently 0, 1, 2, 3, or 4; N is a number between 1 and 30, R 5 and R 6 are independently a linear or branched C1-C4-alkyl radical, preferably a methyl radical, Y is a linear or branched C1-C7 alkylidene, linear or branched C1-C7 alkylene radical, C5-C 12 -Cycloalkylene radical, C5-C 12 - a cycloalkylidene radical, -O-, -S-, -SO-, SO2, or -CO-.

[0051] Phosphorus compounds of formula (10) include, in particular, tributyl phosphate, triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, 2-ethyl cresyl diphenyl phosphate, tri(isopropylphenyl) phosphate, resorcinol bridged oligophosphate esters, and bisphenol A bridged oligophosphate esters. When phosphorus compounds of formula (10) are used, the use of oligomeric phosphate esters of formula (10) derived from bisphenol A is particularly preferred.

[0052] Further preference is given to the use of mixtures of the same structure but different chain lengths, in which case the q value specified is the average of the q values, determined by determining the composition (molecular weight distribution) of the mixture of phosphorus compounds by high pressure liquid chromatography (HPLC) in a mixture of acetonitrile and water (50:50) at 40°C and using this to calculate the average value of q.

[0053] Particularly preferably, bisphenol A-based oligophosphates according to formula (12) (bisphenol A bis(diphenyl phosphate)) with q=1 to 20, in particular q=1.0 to 1.2, are present in the composition according to the invention. [ka]

[0054] Phosphorus compounds of this type are known (see, for example, EP-A-0 363 608, EP-A-0 640 655) or can be prepared in an analogous manner by known methods (see, for example, Ullmanns Enzyklopaedie der technischen Chemie [Ullmann's Encyclopedia of Industrial Chemistry], vol. 18, p. 301 ff., 1979; Houben-Weyl, Methoden der organischen Chemie [Methods of Organic Chemistry], vol. 12 / 1, p. 43; Beilstein vol. 6, p. 177).

[0055] Alternatively, as component C, a cyclic phosphazene according to formula (13) is particularly preferably used, [ka] During the ceremony, R is in each case the same or different, is an amine radical, in each case an optionally halogenated, preferably fluorohalogenated, more preferably monohalogenated, C1-C8-alkyl radical, preferably a methyl, ethyl, propyl or butyl radical, a C1-C8 alkoxy radical, preferably a methoxy, ethoxy, propoxy or butoxy radical, in each case optionally alkyl-substituted, preferably C1-C4-alkyl-substituted and / or halogen-substituted, preferably chlorine- and / or bromine-substituted, C5-C6-cycloalkyl radicals, In each case, optionally alkyl-substituted, preferably C1-C4-alkyl-substituted, and / or halogen-substituted, preferably chlorine, bromine, and / or hydroxy-substituted, C6-C 20an aryloxy radical, preferably a phenoxy radical, a naphthyloxy radical, In each case, optionally alkyl-substituted, preferably C1-C4-alkyl-substituted, and / or halogen-substituted, preferably chlorine- and / or bromine-substituted, C7-C 12 - an aralkyl radical, preferably a phenyl-C1-C4-alkyl radical, or a halogen radical, preferably chlorine or fluorine, or is the OH radical, k is a natural number of 1 to 10, preferably 1 to 8, particularly preferably 1 to 5, and especially preferably 1.

[0056] Commercially available phosphazenes are preferably used here, which typically are ring mixtures of different ring sizes.

[0057] Further preference is given to the following, either individually or in mixtures: propoxyphosphazenes, phenoxyphosphazenes, methylphenoxyphosphazenes, aminophosphazenes, fluoroalkylphosphazenes, and also phosphazenes having the following structure: [ka]

[0058] In compounds 13a-13f shown above, k=1, 2, or 3.

[0059] Preferably, the proportion of phosphorus halogen substituted phosphazenes, for example those consisting of incomplete reactants of the starting materials, is less than 1000 ppm, more preferably less than 500 ppm.

[0060] The phosphazenes can be used alone or in mixtures. The radicals R can always be the same or two or more radicals in the formula can be different. The radicals R of the phosphazenes are preferably identical.

[0061] In one embodiment, only phosphazenes having the same R are used.

[0062] Preferably, the proportion of tetramers (k=2) is, based on component B, 2 mol % to 50 mol %, more preferably 5 mol % to 40 mol %, even more preferably 10 mol % to 30 mol %, particularly preferably 10 mol % to 22 mol %.

[0063] Preferably, the proportion of higher oligomeric phosphazenes (k=3, 4, 5, 6, and 7) is from 0 mol% to 30 mol%, more preferably from 2.5 mol% to 25 mol%, even more preferably from 5 mol% to 20 mol%, particularly preferably from 6 mol% to 15 mol%, based on component B.

[0064] Preferably, the proportion of oligomers with k≧8 is, based on component B, from 0 mol % to 2.0 mol %, preferably from 0.10 mol % to 1.00 mol %.

[0065] More preferably, the phosphazene of component C satisfies all three above conditions with respect to the proportion of oligomers.

[0066] Particularly preferably, phenoxyphosphazenes (all R=phenoxy, formula 13g) are present as component C, either alone or together with further phosphazenes according to formula (13) as component C, the proportion of oligomers with k=1 (hexaphenoxyphosphazenes) being 50 mol % to 98 mol %, particularly preferably 60% to 72% by weight, based on the amount of phenoxyphosphazene. If phenoxyphosphazenes are used, the proportion of oligomers with k=2 is especially preferably 15% to 22% by weight and those with k≧3 being 10% to 13% by weight. [ka]

[0067] Alternatively, component C particularly preferably comprises a phenoxyphosphazene having, based on component C, a proportion of trimers (k=1) of 70 mol% to 85 mol%, a proportion of tetramers (k=2) of 10 mol% to 20 mol%, a proportion of higher oligomeric phosphazenes (k=3, 4, 5, 6, and 7) of 3 mol% to 8 mol%, and 0.1 mol% to 1 mol% of phosphazene oligomers with k≧8. Such a phenoxyphosphazene is particularly preferred.

[0068] In an alternative preferred embodiment, n is defined as the arithmetic mean of k, where n is in the range of 1.10 to 1.75, preferably 1.15 to 1.50, more preferably 1.20 to 1.45, and especially preferably 1.20 to 1.40 (including the range limits).

number

[0069] Phosphazenes and their preparation are described, for example, in EP-A-728811, DE-A-1961668 and WO-A-97 / 40092.

[0070] The oligomer composition in each blend sample was determined after synthesis as follows: 31 Detection and quantification are possible by P NMR (chemical shifts; trimer δ: 6.5 ppm to 10.0 ppm; tetramer δ: -10 ppm to -13.5 ppm; higher oligomers δ: -16.5 ppm to -25.0 ppm).

[0071] Particularly preferably, component C comprises a bisphenol A-based oligophosphate ester according to formula (12) and / or a cyclic phosphazene according to formula (13), most preferably component C is a bisphenol A-based oligophosphate ester according to formula (12) and / or a cyclic phosphazene according to formula (13), particularly preferably component C is a cyclic phosphazene according to formula (13).

[0072] The proportion of the phosphorus-containing flame retardant in the composition of the present invention is at least 2% by weight, based on the entire composition. If the phosphorus-containing flame retardant is an organic phosphate ester, its amount in the composition is 2% to 12% by weight, preferably 2% to 10% by weight, more preferably 2% to 8% by weight, based on the entire composition. With a smaller proportion of organic phosphate ester in the composition, it is possible to achieve increasingly higher Vicat temperatures and thus higher heat distortion resistance. If the phosphorus-containing flame retardant is a phosphazene, its amount in the composition is 2% to 9% by weight, preferably 4% to 8% by weight, based on the entire composition.

[0073] The ratio of the phosphorus-containing flame retardant to the PTFE, ie, component C, that is, the quotient between the amount of the phosphorus-containing flame retardant and the amount of the PTFE, is 40 or less, preferably 32 or less.

[0074] Component D Thermoplastic composition Z may contain one or more additional additives other than component B and component C, which are collectively referred to in the present context as "component D".

[0075] Other conventional additives ("additional additives") are optionally 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%, especially preferably 0.2 wt% to 1.0 wt%, these weight percentages being based on the total weight of the composition. The group of additional additives does not include any fluorine-containing anti-drip agents from component B or any phosphorus-containing flame retardants from component C.

[0076] Such further additives are, as typically added to polycarbonates, in particular heat stabilizers, antioxidants, release agents, UV absorbers, IR absorbers, impact modifiers, antistatic agents, flame retardants different from component C, optical brighteners, light scattering agents, hydrolysis stabilizers, transesterification stabilizers, (organic) dyes, (organic / inorganic) pigments, such as titanium dioxide, compatibilizers and / or laser marking additives, in amounts typical of polycarbonate-based compositions in particular. Such additives are described, for example, in EP-A-0839623, WO-A-96 / 15102, EP-A-0500496 or in "Plastics Additives Handbook", Hans Zweifel, 5th Edition 2000, Hanser Verlag, Munich. These additives, which can be added individually or else as mixtures, are suitable additives according to the invention.

[0077] If additional additives are present at all, further preferred as additional additives is at least one additional additive selected from the group consisting of heat stabilizers, antioxidants, mold release agents, organic dyes, organic pigments, inorganic pigments, especially preferred is one or more antioxidants, heat stabilizers and / or mold release agents.

[0078] It will be understood that such additives can only be added in such amounts if they do not significantly negatively affect the effect of the present invention of high CTI and preferably also do not reduce the Vicat temperature, as specified according to ISO 306:2014-3, VST method B, below 100°C, preferably below 115°C.

[0079] The composition according to the invention may indeed contain, in addition to component C, further flame retardants, but not those selected from the group of alkali metal, alkaline earth metal or ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide or sulfonimide derivatives, and combinations thereof, "derivatives" being taken to mean compounds having a molecular structure in which, instead of a hydrogen atom or a functional group, a different atom or a different atomic group has been present, or in which one or more atoms / atoms have been removed, so that the parent compound is still recognizable.

[0080] Such flame retardants not present in the composition according to the invention are in particular at least one compound 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-dichlorobenzenesulfonate, sodium or potassium 2,4,5-trichlorobenzenesulfonate, sodium or potassium diphenylsulfonate, sodium or potassium 2-formylbenzenesulfonate, sodium or potassium (N-benzenesulfonyl)benzenesulfonamide, or mixtures thereof, among which sodium or potassium perfluorobutane sulfate, sodium or potassium perfluorooctane sulfate, sodium or potassium diphenylsulfonate, or mixtures thereof, in particular potassium perfluoro-1-butanesulfonate (which is commercially available, inter alia, as Bayowet® C4 from Lanxess, Leverkusen, Germany). It is particularly preferred that no further flame retardants are present at all.

[0081] Additives which are particularly preferably present are release agents, more preferably release agents based on fatty acid esters, even more preferably release agents based on stearic acid esters, particularly preferably release agents based on pentaerythritol. The use of pentaerythritol tetrastearate (PETS) and / or glycerol monostearate (GMS) is particularly preferred. If one or more release agents are used, their amount is preferably up to 1.0% by weight (inclusive), more preferably 0.01% to 0.7% by weight, particularly preferably 0.02% to 0.60% by weight, in each case based on the total composition.

[0082] An additive which is also particularly preferably present is a heat stabilizer, the amount of which is preferably up to 0.20% by weight, more preferably 0.01% to 0.10% by weight, even more preferably 0.01% to 0.05% by weight, particularly preferably 0.015% to 0.040% by weight, based on the total composition.

[0083] Suitable heat stabilizers are especially phosphorus-based stabilizers selected from the group of phosphates, phosphites, phosphonites, phosphines, and mixtures thereof.Examples include triphenyl phosphite, alkyl diphenyl phosphite, dialkyl phenyl phosphite, tris(nonylphenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl) phosphite (Irgafos® 168), diisodecyl pentaerythritol diphosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis(2,4-dicumylphenyl) pentaerythritol diphosphite (Do verphos(trademark) S-9228), bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, diisodecyloxypentaerythritol diphosphite, bis(2,4-di-tert-butyl-6-methylphenyl)pentaerythritol diphosphite, bis(2,4,6-tris(tert-butylphenyl)pentaerythritol diphosphite, tristearyl sorbitol triphosphite, tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylene diphosphonite, 6-isooctyl peroxy-2,4,8,10-tetra-tert-butyl-12H-dibenzo[d,g]-1,3,2-dioxaphosphocin, bis(2,4-di-tert-butyl-6-methylphenyl)methyl phosphite, bis(2,4-di-tert-butyl-6-methylphenyl)ethyl phosphite, 6-fluoro-2,4,8,10-tetra-tert-butyl-12-methyldibenzo[d,g]-1,3,2-dioxaphosphocin, 2,2',2''-nitrilo[triethyltris(3,3',5,5'-tetra-tert-butyl-1,1'-biphenyl 2-ethylhexyl (3,3',5,5'-tetra-tert-butyl-1,1'-biphenyl-2,2'-diyl) phosphite, 5-butyl-5-ethyl-2-(2,4,6-tri-tert-butylphenoxy)-1,3,2-dioxaphosphiran, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, triphenylphosphine (TPP), trialkylphenylphosphine, bisdiphenylphosphinoethane, or trinaphthylphosphine.These are used alone or in mixtures with heat stabilizers or antioxidants, for example Irganox® B900 (a mixture of Irgafos® 168 and Irganox® 1076 in a ratio of 4:1) or a mixture of Doverphos® S-9228 with Irganox® B900 or Irganox® 1076. Particularly preferably, triphenylphosphine (TPP), Irgafos® 168, or tris(nonylphenyl)phosphite, or mixtures thereof, are used.

[0084] It is also possible to use phenolic antioxidants, such as alkylated monophenols, alkylated thioalkylphenols, hydroquinones and alkylated hydroquinones.Particular preference is given to using 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), preferably in an amount of 0.02% to 0.5% by weight.

[0085] It is also possible to add sulfonates or alkyl phosphates, such as mono-, di-, and / or trihexyl phosphate, triisooctyl phosphate, and / or trinonyl phosphate, as transesterification inhibitors. The alkyl phosphate used is preferably triisooctyl phosphate (tris-2-ethylhexyl phosphate). It is also possible to use mixtures of various mono-, di-, and / or trialkyl phosphates. Triisooctyl phosphate is preferably used in an amount of 0.003% to 0.05% by weight, more preferably 0.005% to 0.04% by weight, particularly preferably 0.01% to 0.03% by weight, based on the total composition.

[0086] Examples of impact modifiers are: core-shell polymers, such as ABS or MBS; olefin-acrylate copolymers, such as the Elvaloy™ variety from DuPont or the Paraloid™ variety from Dow; silicone acrylate rubbers, such as the Metablen™ variety from Mitsubishi Rayon Co., Ltd. The composition according to the present invention already has an exceptional property profile without additional impact modifiers. Therefore, the composition according to the present invention preferably does not contain impact modifiers.

[0087] The thermoplastic composition Z, which contains the components A, B, C and, optionally, D in admixture, can be prepared using a powder premix. It is also possible to use a plurality of pellet materials or premixes of pellet materials and powders with the additives according to the invention. It is also possible to use a premix formed from a solution of the component mixture in a suitable solvent, optionally followed by homogenization of the solution and subsequent removal of the solvent. In particular, the additives and further constituents, referred to as component D of the thermoplastic composition, can also be introduced by known methods or in the form of a masterbatch. The use of masterbatches is particularly suitable for the introduction of the additives and further constituents, and masterbatches based on the respective polymer matrix are particularly used.

[0088] The thermoplastic composition Z can be, for example, extruded. After extrusion, the extrudate can be cooled and crushed. The premix can also be mixed together in the melt in the plasticizing unit of an injection molding machine. In this case, the melt is directly converted into a molded article in a subsequent step.

[0089] The present invention also provides the use of the following combination of a fluorine-containing anti-drip agent containing 0.25% by weight to 5% by weight of a polytetrafluoroethylene and at least 2% by weight of a phosphorus-containing flame retardant to achieve a CTI of 600V as specified according to IEC 60112:2009 for an aromatic polycarbonate-based composition, wherein the ratio of the phosphorus-containing flame retardant to PTFE is not more than 40, preferably not more than 32, and when the phosphorus-containing flame retardant is b1) an organic phosphate ester, the amount of the phosphorus-containing flame retardant is 2% by weight to 12% by weight, and when the phosphorus-containing flame retardant is b2) a phosphazene, the amount of the phosphorus-containing flame retardant is 2% by weight to 9% by weight, the amounts stated being based on the entire composition obtained.

[0090] It is clear that the embodiments described above for the thermoplastic composition Z as preferred etc. are equally applicable to the use of the present invention.

[0091] Various embodiments of the present invention are described below:

[0092] 1. An EE part, a first conductor and a second conductor at a first distance d1 and a second distance d2 from each other; Including, They are connected via a thermoplastic composition Z, which is in direct contact with the first and second electrical conductors; distance d1 is the shortest distance between the first and second conductors along the surface of the thermoplastic material M; The distance d2 is the shortest distance through air between the first conductor and the second conductor, and d2 is selected to prevent sparks through air at each operating voltage; d1 is the following at the working voltage U listed below: d1i(0V≦U≦250V):1.3mm~<2.5mm d1ii(250V <U≦500V)=2.5mm~<5.0mm d1iii(500V <U≦1000V)=5.0mm~<10.0mm and the thermoplastic composition Z comprises the following components: A) at least 80% by weight of an aromatic polycarbonate based on bisphenol A; B) 0.25% by weight to 5% by weight of a fluorine-containing drip prevention agent containing polytetrafluoroethylene; C) at least 2% by weight of a phosphorus-containing flame retardant; wherein the quotient of the amount of phosphorus-containing flame retardant and the amount of polytetrafluoroethylene is 40 or less, preferably 32 or less; The phosphorus-containing flame retardant b1) organic phosphate esters, In this case, the amount of the phosphorus-containing flame retardant is 2% by weight to 12% by weight; The phosphorus-containing flame retardant b2) phosphazenes, In this case, the amount of the phosphorus-containing flame retardant is 2% by weight to 9% by weight; EE part, the thermoplastic composition Z does not contain a flame retardant selected from the group of alkali metal, alkaline earth metal or ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide or sulfonimide derivatives.

[0093] 2. An EE part according to embodiment 1, wherein the phosphorus-containing flame retardant is a phosphazene or a mixture of different phosphazenes.

[0094] 3. The EE part according to embodiment 1, wherein the phosphorus-containing flame retardant comprises a cyclic phosphazene and / or a phosphorus compound of formula (10).

[0095] 4. The phosphorus-containing flame retardant is a cyclic phosphazene and / or a phosphorus compound of formula (10), [ka] During the ceremony, R 1 , R 2 , R 3 , and R 4are independently a C1-C8-alkyl radical, which in each case is optionally halogenated, in each case branched or unbranched, and / or a C5-C6-cycloalkyl radical, a C6-C 20 -aryl radical, or C7-C 12 - aralkyl radicals, which in each case are optionally substituted by branched or unbranched alkyl and / or halogen, preferably chlorine and / or bromine, n is independently 0 or 1; q is a value between 0 and 30; EE part according to embodiment 1, wherein X is a monocyclic or polycyclic aromatic radical having 6 to 30 carbon atoms, or a linear or branched chain aliphatic radical having 2 to 30 carbon atoms, each of which may be substituted or unsubstituted and may be bridged or non-bridged.

[0096] 5. The phosphorus-containing flame retardant is an organophosphate ester of formula (11): [ka] During the ceremony, R 1 , R 2 , R 3 , and R 4 are each independently a linear or branched C1-C8 alkyl radical and / or an optionally linear or branched alkyl substituted C5-C6 cycloalkyl radical, a C6-C 10 -Aryl radical or C7-C 12 -aralkyl radical, n is independently 0 or 1; q is independently 0, 1, 2, 3, or 4; N is a number between 1 and 30, R5 and R6 are independently a linear or branched C1-C4 alkyl radical, preferably a methyl radical; Y is a linear or branched C1-C7 alkylidene, linear or branched C1-C7 alkylene radical, C5-C 12 -Cycloalkylene radical, C5-C 12 - a cycloalkylidene radical, -O-, -S-, -SO-, SO2 or -CO-, Or, is a phosphazene of formula (13g), [ka] 4. The EE component of embodiment 1 or 3, wherein k=1, 2, or 3.

[0097] 6. The cyclic phosphazene is a phosphazene of formula (13): [ka] During the ceremony, R is in each case the same or different, is an amine radical, in each case an optionally halogenated, preferably fluorohalogenated, more preferably monohalogenated, C1-C8-alkyl radical, preferably a methyl, ethyl, propyl or butyl radical, a C1-C8 alkoxy radical, preferably a methoxy, ethoxy, propoxy or butoxy radical, in each case optionally alkyl-substituted, preferably C1-C4-alkyl-substituted and / or halogen-substituted, preferably chlorine- and / or bromine-substituted, C5-C6-cycloalkyl radicals, In each case, optionally alkyl-substituted, preferably C1-C4-alkyl-substituted, and / or halogen-substituted, preferably chlorine, bromine, and / or hydroxy-substituted, C6-C 20 an aryloxy radical, preferably a phenoxy radical, a naphthyloxy radical, In each case, optionally alkyl-substituted, preferably C1-C4-alkyl-substituted, and / or halogen-substituted, preferably chlorine- and / or bromine-substituted, C7-C 12 - an aralkyl radical, preferably a phenyl-C1-C4-alkyl radical, or a halogen radical, preferably chlorine or fluorine, or is the OH radical, EE component according to embodiment 1, 3 or 4, wherein k is a natural number from 1 to 10, preferably a number from 1 to 8, particularly preferably a number from 1 to 5, especially preferably 1.

[0098] 7. The phosphorus compound of formula (10) is a bisphenol A-based oligophosphate ester of formula (12), [ka] The EE part according to embodiment 3 or 4, wherein q=1 to 20, in particular q=1.0 to 1.2.

[0099] 8. An EE part according to any of embodiments 1 to 7, having a degree of protection IP6K9K according to ISO 20653:2013-02.

[0100] 9. An EE part according to any one of embodiments 1 to 8, wherein d2≧1.2 mm.

[0101] 10. An EE part according to any of the previous embodiments, wherein the aromatic polycarbonate is a bisphenol A-based homopolycarbonate.

[0102] 11. The thermoplastic composition Z is selected from the group consisting of: D) at least one additive selected from the group consisting of release agents, heat stabilizers, antioxidants, dyes, impact modifiers, pigments, ultraviolet absorbers, infrared absorbers, fluorescent brighteners, hydrolysis stabilizers, ester exchange stabilizers, compatibilizers, laser marking additives, flow improvers, and mixtures thereof; The EE part according to any of the previous embodiments.

[0103] 12. An EE part according to any of embodiments 1 to 10, wherein the thermoplastic composition Z also contains at least one additive selected from the group consisting of release agents, heat stabilizers, antioxidants, dyes, pigments, transesterification stabilizers, flow improvers, and mixtures thereof.

[0104] 13. An EE part according to any of the previous embodiments, wherein the thermoplastic composition does not include any further components.

[0105] 14. The EE part according to any of embodiments 1-4, 6, and 8-13, wherein the phosphorus-containing flame retardant is a phosphazene, and the amount thereof is 4% by weight to 8% by weight of the total composition.

[0106] 15. The EE part according to any of embodiments 1, 3-5, and 7-13, wherein the phosphorus-containing flame retardant is an organic phosphate ester, and the amount thereof is 2% by weight to 10% by weight of the total composition.

[0107] 16. An EE part according to any of the previous embodiments that is part of a high voltage switch, inverter, relay, electronic connector, electrical connector, circuit breaker, photovoltaic power system, electric motor, heat sink, electric vehicle charger or charging plug, electrical junction box, smart meter housing, miniature circuit breaker, busbar.

[0108] 17. The following: d1i(0V≦U≦250V):1.3mm~<1.8mm d1ii(250V <U≦500V)=2.5mm~<3.6mm d1iii(500V <U≦1000V)=5.0mm~<7.1mm EE part according to any of the previous embodiments.

[0109] 18. An EE part according to any of the previous embodiments, designed for a working voltage of at least 400V.

[0110] 19. An EE part according to any of the previous embodiments, wherein the thermoplastic composition Z includes not only component A, component B, and component C, but also, as component D, alone, one or more heat stabilizers, antioxidants, mold release agents, dyes, pigments, and mixtures thereof.

[0111] 20. An EE part according to any of the previous embodiments, wherein the thermoplastic composition Z has a CTI of 600V as specified according to IEC 60112:2009.

[0112] 21. An EE assembly including an EE part according to any of the previous embodiments, the EE assembly having an IP6K9K degree of protection according to ISO 20653:2013-02.

[0113] 22.The working voltage of the EE assembly is at least 400V, EE assembly.

[0114] 23. An EE assembly according to any of embodiments 21 and 22 for the electromobility sector.

[0115] 24. Use of a thermoplastic composition as defined as part of any of embodiments 1 to 15 of an aromatic polycarbonate-based composition containing at least 80% by weight of an aromatic polycarbonate based on bisphenol A to achieve a CTI of 600V as specified according to IEC 60112:2009, the amounts stated being based on the entire resulting composition.

[0116] 25. The use according to embodiment 24, wherein the aromatic polycarbonate is a bisphenol A-based homopolycarbonate. EXAMPLES

[0117] 1. Description of raw materials and testing methods a) Raw materials Component A-1: ​​A linear polycarbonate based on bisphenol A, which has a melt volume flow rate of 12 cm 3 / (10 min) (in accordance with ISO 1133:2012-03 at a test temperature of 300° C. and a load of 1.2 kg) and contains 250 ppm (=0.025% by weight, based on the total weight of component A) of triphenylphosphine heat stabilizer as component D-3.

[0118] Component A-2: A linear polycarbonate based on bisphenol A, which has a melt volume flow rate of 6 cm 3 / (10 min) (in accordance with ISO 1133:2012-03 at a test temperature of 300°C and a load of 1.2 kg).

[0119] Component B-1: ADS5000 SAN encapsulated polytetrafluoroethylene (approximately 50% by weight PTFE (a fluorine-containing anti-drip agent) and approximately 50% by weight SAN), manufactured by Chemical Innovation Co., Ltd. Thailand.

[0120] Component B-2: Fluorine-containing anti-drip agent. Teflon CFP6000X polytetrafluoroethylene, manufactured by Chemours Netherlands BV.

[0121] Component C-1: Organic phosphate ester of formula (12), q=1.0 to 1.2. Bisphenol A bis(diphenyl phosphate), manufactured by ADEKA Corporation.

[0122] Component C-2: Rabitle FP110 phenoxycyclophosphazene, manufactured by Fushimi Pharmaceutical Co., Ltd. (Japan), formula (13g), trimer ratio (k=1) is approximately 68 mol%.

[0123] Component Cx: Potassium perfluoro-1-butanesulfonate, commercially available as Bayowet™ C4 from Lanxess AG, Leverkusen, Germany, CAS number 29420-49-3.

[0124] Component D-1: Mold release agent. Pentaerythritol tetrastearate, commercially available as Loxiol VPG 861 from Emery Oleochemicals Group.

[0125] Component D-2: Mixture of heat stabilizers and antioxidants. Irganox® B900 from BASF (a 4:1 weight ratio mixture of Irgafos® 168 (tris(2,4-di-tert-butylphenyl) phosphite) and Irganox® 1076 (octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate)).

[0126] b) Test method Comparative Tracking Index (CTI): For the purpose of determining the comparative tracking index, the compositions described herein were tested according to the rapid test method according to IEC 60112:2009. For this purpose, a 0.1% ammonium chloride test solution (395 ohm·cm resistivity) was dropped onto the surface of a test specimen with dimensions 60 mm×40 mm×4 mm, between two adjacent electrodes spaced 4 mm apart, with a time interval of 30 seconds. A test voltage was applied between the electrodes and varied over the course of the test. The first test specimen was tested with a starting voltage of 300 V or 350 V. A maximum of 50 drops in total per voltage (one drop every 30 seconds) were dropped as long as no tracking current of more than 0.5 A occurred for 2 seconds or the specimen did not burn. After 50 drops, the voltage was increased by 50 V and a new specimen was tested at this increased voltage according to the procedure described above. This process continued until either 600 V was reached or a tracking current or burning occurred. If any of the above effects occurred already in less than 50 drops, the voltage was reduced by 25V and a new specimen was tested at this reduced voltage. The voltage was reduced until the test completed 50 drops without causing tracking current or burning. Thus, this procedure was used to identify the maximum possible voltage at which the composition could withstand 50 drops of test solution without causing tracking current. Finally, for confirmation, four more specimens were tested with 50 drops each at the maximum voltage specified. This confirmed value was reported as the CTI in the examples. The 100 drop value was not specified because it was a "rapid test method based on" the specified standard.

[0127] Flame Retardant: The flame retardancy of the polycarbonate compositions was tested at a thickness of 2 mm according to Underwriters Laboratories method UL 94 V. The tested test bars were previously conditioned at 20% relative humidity and 70° C. ambient temperature for 7 days.

[0128] Depending on the behavior of the specimens, they are assigned to various flammability classes, including time to flame extinguish, drip resistance, or whether the material produces flammable drips. Hereinafter, the identified classes will be designated V0, V1, and V2. These are established based on a total of five specimens tested.

[0129] V0: Specimens that, when placed at 180° (perpendicular) with their long axis to the flame, have an average afterflame time of 10 seconds or less after the flame is removed and do not produce any drips of plastic particles that ignite cotton wool placed under the specimen. The total afterflame time with two flame applications to each of the five specimens is a maximum of 50 seconds.

[0130] V1: In contrast to V0, the average maximum afterflame time in this case is less than 30 seconds, but again no ignition of dripping particles or cotton wool is permitted. The total afterflame time with two flame applications to each of the five specimens is less than 250 seconds.

[0131] V2: In contrast to V0 and V1, this classification results in the formation of drips of plastic particles which ignite the cotton wool. The individual afterflame times are less than 30 seconds and the total afterflame time of two flame applications to each of the five specimens is less than 250 seconds.

[0132] f: If the afterflame time exceeds the above, this test does not assign flame retardancy.

[0133] Heat Distortion Resistance: The heat distortion resistance of the compositions was determined on test specimens with dimensions 80 mm x 10 mm x 4 mm based on the Vicat softening temperature (Method B, test force 50 N, heating rate 50 K / h) according to ISO 306:2014-3.

[0134] 2. Preparation of Test Specimens The compositions were prepared in a Coperion 25 mm twin screw extruder with a throughput of 20 kg / h. The temperature of the polymer melt in the extruder was 260° C.-280° C. and the average screw speed was 225 rpm.

[0135] Test specimens measuring 60mm x 40mm x 4mm were produced from the molding compound using standard injection molding techniques with a melt temperature of 280°C and a mold temperature of 80°C.

[0136] result In the following table, "nt" means "not tested." * " means "obtained from UL Yellow Card."

[0137] [Table 1]

[0138] [Table 2]

[0139] The examples summarized in Tables 1 and 2 include compositions consisting of polycarbonate, anti-drip agent (PTFE / SAN), and flame retardant, as well as additional additives. By adding small amounts of phosphorus-based flame retardants, such as BDP, together with PTFE, it is possible to achieve a CTI of 600V as well as a V0 classification at low wall thickness, which constitutes an attractive property package for the above mentioned applications (see E-3 to E-13). Flame retardant alone does not provide an improvement in CTI compared to non-FR polycarbonate compositions (see V-5 and V-2). To obtain a CTI of 600V, a higher amount of flame retardant must be balanced with a higher amount of anti-drip agent (see E-13 and V-8). Further results in Table 2 include compositions using phosphazenes as flame retardants (see E-14 to E-17), which achieve similarly high CTI and V0 classification. Additionally, corresponding compositions using pure PTFE rather than a PTFE / SAN masterbatch are included, which also achieve a CTI and V0 of 600V based on the total PTFE content of the composition (see E-19 to E-22). Finally, comparative examples V-23 to V-26 show that inorganic flame retardants based on, for example, alkyl sulfonates do not provide high tracking current resistance.

Claims

1. An EE part, a first conductor and a second conductor at a first distance d1 and a second distance d2 from each other; Including, They are connected via a thermoplastic composition Z, which is in direct contact with the first electrical conductor and the second electrical conductor; the distance d1 is the shortest distance between the first and second electrical conductors along a surface of the thermoplastic material M; the distance d2 is the shortest distance through air between the first conductor and the second conductor, and d2 is selected to prevent sparks through air at each operating voltage; d1 is, at the working voltage U listed below, d1i (0V≦U≦250V): 1.3mm~<2.5mm d1ii (250V<U≦500V)=2.5mm~<5.0mm d1iii (500V<U≦1000V)=5.0mm~<10.0mm and the thermoplastic composition Z comprises the following components: A) at least 80% by weight of an aromatic polycarbonate based on bisphenol A; B) 0.25% to 5% by weight of a fluorine-containing anti-drip agent containing polytetrafluoroethylene; C) at least 2 wt. % of a phosphorus-containing flame retardant; wherein the quotient of the amount of the phosphorus-containing flame retardant and the amount of polytetrafluoroethylene is 40 or less; The phosphorus-containing flame retardant is b1) organic phosphates, wherein the amount of the phosphorus-containing flame retardant is 2% by weight to 12% by weight; The phosphorus-containing flame retardant is b2) phosphazenes, wherein the amount of the phosphorus-containing flame retardant is 2% by weight to 9% by weight; EE part, wherein said thermoplastic composition Z does not contain a flame retardant selected from the group of alkali metal, alkaline earth metal or ammonium salts of aliphatic or aromatic sulfonic acid, sulfonamide or sulfonimide derivatives.

2. The phosphorus-containing flame retardant is an organic phosphate ester of formula (11), 【Chemistry 1】 During the ceremony, R １ , R ２ , R ３ , and R ４ each independently represents a linear or branched chain C １ ~C ８ - alkyl radicals and / or optionally linear or branched alkyl substituted C ５ ~C ６ -cycloalkyl radical, C ６ ~C １０ -aryl radical, or C ７ ~C １２ - an aralkyl radical, n is independently 0 or 1; q is independently 0, 1, 2, 3, or 4; N is a number from 1 to 30, R ５ and R ６ are independently linear or branched chain C １ ~C ４ is an alkyl radical, preferably a methyl radical, Y is a linear or branched chain C １ ~C ７ -Alkylidene, linear or branched chain C １ ~C ７ - alkylene radical, C ５ ~C １２ -cycloalkylene radical, C ５ ~C １２ -Cycloalkylidene radical, -O-, -S-, -SO-, SO ２ or -CO-; Or, is a phosphazene of formula (13g), 【Chemistry 2】 2. The EE part of claim 1, wherein k=1, 2, or 3.

3. 3. The EE part according to claim 1 or 2, wherein the aromatic polycarbonate is a bisphenol A homopolycarbonate.

4. The thermoplastic composition comprises: D) at least one additive selected from the group consisting of release agents, heat stabilizers, antioxidants, dyes, impact modifiers, pigments, ultraviolet absorbers, infrared absorbers, fluorescent brighteners, hydrolysis stabilizers, ester exchange stabilizers, compatibilizers, laser marking additives, flow improvers, and mixtures thereof; The EE part according to any one of claims 1 to 3, further comprising:

5. EE part according to any one of claims 1 to 4, wherein the thermoplastic composition Z comprises not only component A, component B, and component C, but also as component D, alone one or more heat stabilizers, antioxidants, mold release agents, dyes, pigments, and mixtures thereof.

6. The EE part according to any one of claims 1 to 5, wherein the EE part is a part of a high voltage switch, an inverter, a relay, an electronic connector, an electrical connector, a circuit breaker, a photovoltaic power generation system, an electric motor, a heat sink, a charger or a charging plug for an electric vehicle, an electrical junction box, a smart meter housing, a miniature circuit breaker, or a busbar.

7. below: d1i (0V≦U≦250V): 1.3mm~<1.8mm d1ii (250V<U≦500V)=2.5mm~<3.6mm d1iii (500V<U≦1000V)=5.0mm~<7.1mm The EE part according to any one of claims 1 to 6,

8. EE part according to any one of claims 1 to 7, designed for a working voltage of at least 400V.

9. EE part according to any one of claims 1 to 8, wherein the thermoplastic composition does not comprise any further components.

10. EE part according to any one of claims 1 to 9, wherein the thermoplastic composition Z contains 4% to 8% by weight of cyclophosphazene.

11. 11. An EE assembly comprising an EE part according to any one of claims 1 to 10, the EE assembly having an IP6K9K degree of protection according to ISO 20653:2013-02.

12. 12. The EE assembly of claim 11, wherein the working voltage of the EE assembly is at least 400V.

13. For aromatic polycarbonate-based compositions containing at least 80% by weight of aromatic polycarbonate based on bisphenol A, the following combinations are used to achieve a CTI of 600V as specified according to IEC 60112:2009: 0.25% to 5% by weight of a fluorine-containing anti-drip agent containing polytetrafluoroethylene; at least 2% by weight of a phosphorus-containing flame retardant; wherein the ratio of the phosphorus-containing flame retardant to PTFE is 40 or less; The phosphorus-containing flame retardant is b1) organic phosphates, wherein the amount of the phosphorus-containing flame retardant is 2% by weight to 12% by weight; The phosphorus-containing flame retardant is b2) phosphazenes, wherein the amount of the phosphorus-containing flame retardant is 2% by weight to 9% by weight; The amounts listed are based on the total composition obtained.

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