Flame-retardant impact-modified thermoplastic composition

Abstract

The present invention relates to a thermoplastic composition comprising, based on the weight of the composition: (A) 60 to 95% by weight of an aromatic polycarbonate, (B) 3 to 15% by weight of an impact modifier, (C) 2 to 20% by weight of a flame retardant additive comprising at least one cyclic phosphazene (C-1) and at least one oligophosphoric acid ester (C-2), (D) 0 to 5% by weight of other components; wherein the amount of the combination of (A) to (D) is 100% by weight, and wherein the composition has: a notched Izod impact resistance, determined according to ASTM D-256 at a temperature of 23 DEG C, of at least 300 J / m, preferably 300 to 900 J / m; a melt flow rate, determined according to ASTM D1238 (300 DEG C, 1.2 kg), of at least 7.0 g / 10 min, preferably 7.0 to 20.0 g / 10 min; and a UL94 rating of V0 at a thickness of 0.75 mm.

Description

Technical Field

[0001] The present invention relates to flame retardant (FR) impact modified thermoplastic compositions comprising a blend of an aromatic polycarbonate, an impact modifier and a flame retardant additive. The present invention further relates to articles comprising or consisting of such compositions. Background Art

[0002] Such compositions are known per se in the prior art and can be used for interior or exterior automotive applications as well as electrical and electronic applications, such as mobile devices, laptops, monitors, tablets, data storage etc., computers, (tele)communication applications, across other different fields and applications, such as consumer products and appliances, automotive lighting, automotive under the hood, electric vehicle applications, electrical components, electronic displays, energy storage and lighting applications.

[0003] In many of these applications, there is a trend towards parts that have, at least in part, relatively small wall thicknesses. Therefore, thermoplastic compositions used to make such applications require a set of optimized flow and mechanical properties, such as impact and stiffness in particular, while maintaining good flame retardancy, such as UL V0 rating in particular.

[0004] US2016 / 0194495 discloses a blended thermoplastic composition comprising: a) about 60 wt % to about 80 wt % of a polycarbonate component, the polycarbonate component comprising 5-15 wt % of a polycarbonate-polysiloxane copolymer, based on the total weight of the composition; b) greater than about 0 wt % to about 5 wt % of an impact modifier component; c) greater than about 0 wt % to about 25 wt % of a mineral filler component; and d) about 5 wt % to about 15 wt % of a flame retardant component; wherein the combined weight percentage value of all components does not exceed about 100 wt %; and wherein all weight percentage values ​​are based on the total weight of the composition.

[0005] US2019 / 0255825 discloses a fiber composite material comprising at least one fiber material layer embedded in an aromatic polycarbonate-based composition, the composition comprising A) an aromatic polycarbonate, B) 1% to 14% by weight of talc, C) 7% to 15% by weight of at least one cyclic phosphazene of formula (1)

[0006]

[0007] wherein R is identical or different and is an amine group, a C1 to C8 alkyl group, which is in each case optionally halogenated, a C1 to C8 alkoxy group, a C5 to C6 cycloalkyl group, which is in each case optionally substituted by alkyl and / or substituted by halogen, a C6 to C8 cycloalkyl group, which is in each case optionally substituted by alkyl and / or halogen and / or hydroxyl. 20aryloxy groups, C7 to C 5-11-12-13-16 substituted in each case by alkyl and / or halogen 12 an aralkyl group, or a halogen group or an OH group, k is an integer from 1 to 10, D) 0% to 11% by weight of at least one phosphorus compound of the general formula (V)

[0008]

[0009] Where R 1 , R 2 , R 3 and R 4 each independently a C1 to C8 alkyl group, which is in each case optionally halogenated and in each case branched or unbranched, and / or a C5 to C6 cycloalkyl group, a C6 to C 20 Aryl group or C7 to C 12 arylalkyl groups, which are in each case optionally substituted by branched or unbranched alkyl groups and / or halogen, n is independently 0 or 1, q is an integer from 0 to 30, X is a monocyclic or polycyclic aromatic group having 6 to 30 carbon atoms or a linear or branched aliphatic group having 2 to 30 carbon atoms, each of which can be substituted or unsubstituted and bridged or unbridged; E) 0% to 0.2% by weight of at least one stabilizer selected from alkyl phosphates, ethylenediaminetetraacetic acid and / or citric acid, F) optional further additives, wherein the composition does not contain PTFE. Summary of the invention

[0010] In view of the foregoing, an object of the present invention is to provide a thermoplastic composition having a desirable combination of thin-wall flame retardancy, impact resistance, stiffness and flowability, which allows it to be suitable for the manufacture of thin-wall structural parts.

[0011] This object is at least partially achieved according to the present invention, which relates to a thermoplastic composition comprising, based on the weight of the composition:

[0012] (A) 60 to 95% by weight of an aromatic polycarbonate,

[0013] (B) 3 to 15% by weight of an impact modifier,

[0014] (C) 2 to 20 wt% of a flame retardant additive comprising at least one cyclic phosphazene (C-1) and at least one oligomeric phosphate (C-2)

[0015] (D) 0 to 5 wt % of other components;

[0016] The combined amount of (A) to (D) is 100% by weight.

[0017] and wherein the composition has or is selected to have:

[0018] - a notched Izod impact resistance measured at a temperature of 23° C. according to ASTM D-256 of at least 300 J / m, preferably from 300 to 900 J / m;

[0019] - a melt flow rate determined according to ASTM D1238 (300° C., 1.2 kg) of at least 7.0 g / 10 min, preferably from 7.0 to 20.0 g / 10 min; and

[0020] -UL94 rating of V0 at 0.75mm thickness.

[0021] The present invention will now be described in more detail.

[0022] Polycarbonate (PC)

[0023] Two different techniques are usually used to make aromatic polycarbonates. In the first technique, which is called the interfacial technique or interfacial process, phosgene is reacted with bisphenol, typically bisphenol A (BPA) in the liquid phase. Another well-known technique is the so-called melt technique, sometimes also called melt transesterification or melt polycondensation technique. In the melt technique or melt process, bisphenol, typically BPA, is reacted with carbonate, typically diphenyl carbonate (DPC) in the melt phase. It is known that the aromatic polycarbonates obtained by the melt transesterification process are structurally different from the aromatic polycarbonates obtained by the interfacial process. In this regard, it is particularly noted that the so-called "melt polycarbonate" typically has a minimum amount of Fries branches, which are generally not present in "interfacial polycarbonates". In addition, melt polycarbonates typically have a higher number of phenolic hydroxyl end groups, while the polycarbonates obtained by the interfacial process are typically end-capped and have a phenolic hydroxyl end group of at most 150 ppm, preferably at most 50 ppm, and more preferably at most 10 ppm.

[0024] The thermoplastic composition of the present invention comprises 60 to 95% by weight, preferably 70 to 90% by weight of an aromatic polycarbonate as component (A), based on the weight of the composition. According to the present invention, it is preferred that the aromatic polycarbonate comprises a bisphenol A polycarbonate homopolymer (also referred to herein as bisphenol A polycarbonate) or a mixture of bisphenol A polycarbonate or consists of them. Preferably, the aromatic polycarbonate of the present invention disclosed herein comprises at least 75% by weight, preferably at least 95% by weight of bisphenol A polycarbonate, based on the total amount of aromatic polycarbonate. More preferably, the aromatic polycarbonate in the composition consists essentially of bisphenol A polycarbonate or consists of bisphenol A polycarbonate. Preferably, the aromatic polycarbonate has a weight average molecular weight (Mw) of 15,000 to 60,000 g / mol measured using a polycarbonate standard using gel permeation chromatography.

[0025] In one aspect, the polycarbonate is an interfacial polycarbonate.

[0026] In another aspect, the polycarbonate is a melt polycarbonate.

[0027] In yet another aspect, the polycarbonate is a mixture of 20 to 80 wt % or 40 to 60 wt % interfacial polycarbonate and 80 to 20 wt % or 60 to 40 wt % molten polycarbonate, based on the weight of the aromatic polycarbonate.

[0028] The polycarbonate can be a mixture of two or more aromatic polycarbonates having different melt flow rates. For example, the aromatic polycarbonate can be a mixture of two or more bisphenol A polycarbonate homopolymers having weight average molecular weights different from each other. The polycarbonate can have a melt flow rate measured according to ASTM D1238 (300° C., 1.2 kg) of 1 to 50 g / 10 min, particularly 2 to 30 cc / 10 min. On the other hand, the polycarbonate includes a polycarbonate copolymer comprising a structural unit of bisphenol A and a structural unit from another bisphenol.

[0029] The aromatic polycarbonate preferably does not contain 5 to 15 weight percent of a polycarbonate-polysiloxane copolymer, based on the weight of the thermoplastic composition.

[0030] Preferably, the aromatic polycarbonate does not comprise a polycarbonate-polysiloxane copolymer. More preferably, the thermoplastic composition does not comprise a polycarbonate-polysiloxane copolymer in an amount of at least 3 wt.%. Even more preferably, the thermoplastic composition does not comprise a polycarbonate-polysiloxane copolymer.

[0031] Impact modifiers

[0032] Thermoplastic compositions of the present invention include impact modifiers as component (B). Suitable impact modifiers are typically high molecular weight elastomeric materials derived from olefins, monovinyl aromatic monomers, acrylic acid and methacrylic acid and their ester derivatives, and conjugated dienes. The polymer formed by the conjugated diene can be fully or partially hydrogenated. The elastomeric material can be in the form of a homopolymer or copolymer, including random copolymers, block copolymers, radial block copolymers, graft copolymers and core-shell copolymers. The combination of impact modifiers can be used.

[0033] The impact modifier is preferably selected from acrylonitrile-butadiene-styrene impact modifiers, methyl methacrylate-butadiene-styrene impact modifiers, ethylene-acrylate copolymer impact modifiers, ethylene-acrylate-glycidol copolymer impact modifiers and mixtures of two or more of the foregoing.

[0034] Preferably, the impact modifier is selected from acrylonitrile-butadiene-styrene impact modifier and methyl methacrylate-butadiene-styrene impact modifier and / or a mixture thereof.

[0035] The amount of impact modifier is 3 to 15 wt % based on the weight of the composition. Preferably, the impact modifier is included in the composition in an amount of 3 to 10 wt %, preferably 4 to 8 wt %.

[0036] In another aspect, the thermoplastic composition further comprises 1 to 5 wt % of a silicone-acrylate composite rubber comprising a polyorganosiloxane rubber component and a polyalkyl (meth)acrylate rubber component. Silicone-acrylate composite rubbers are known and are described, for example, in U.S. Pat. No. 5,807,914, EP 0430134, and U.S. Pat. No. 4,888,388 and references therein.

[0037] Suitable silicone rubber components of silicone / acrylate rubbers are silicone rubbers with grafting active sites, the preparation methods of which are described, for example, in U.S. Pat. No. 2,891,920, U.S. Pat. No. 3,294,725, EP0249964, EP0430134 and U.S. Pat. No. 4,888,388 and references therein. Such silicone-acrylate composite rubbers are preferably composite rubbers with grafting active sites, containing 10 to 90% by weight of a silicone rubber component and 90 to 10% by weight of a poly(meth)acrylate alkyl ester rubber component. The two rubber components described interpenetrate into the composite rubber so that they cannot be separated substantially.

[0038] Flame retardant additives

[0039] Phosphorus-containing compounds are usually used as FR additives in thermoplastic compositions. These are selected from mono- and oligomeric phosphoric acid esters and phosphonic acid esters, phosphonic acid amines and phosphazenes. Mixtures of several components selected from one or several of these groups can also be used as FR additives. According to the invention, the thermoplastic composition comprises 2 to 20 wt.-%, based on the weight of the composition, of a FR additive comprising at least one cyclic phosphazene (C-1) and at least one oligomeric phosphoric acid ester (C-2).

[0040] At least one phosphazene (C-1) is a cyclic phosphazene, which is preferably selected from propoxyphosphazene, phenoxyphosphazene, methylphenoxyphosphazene, aminophosphazene and fluoroalkylphosphazene and phosphazenes having the following structure (X):

[0041]

[0042] in:

[0043] ● The groups R are the same or different and are each

[0044] ○Amine group,

[0045] o in each case optionally halogenated, preferably fluorinated, more preferably monohalogenated C1-C8-alkyl, preferably methyl, ethyl, propyl or butyl,

[0046] o C1 to C8 alkoxy, preferably methoxy, ethoxy, propoxy or butoxy,

[0047] o C5 to C6 cycloalkyl, which is optionally substituted in each case by alkyl, preferably C1 to C4 alkyl, and / or halogen, preferably chlorine and / or bromine,

[0048] ○C6 to C 20 aryloxy, preferably phenoxy, naphthoxy, which is optionally substituted in each case by alkyl, preferably C1 to C4-alkyl, and / or halogen, preferably chlorine, bromine, and / or hydroxy,

[0049] ○C7 to C 12 Aralkyl, preferably phenyl-C1 to C4-alkyl, which is optionally substituted in each case by alkyl, preferably C1 to C4-alkyl, and / or halogen, preferably chlorine and / or bromine, or

[0050] o a halogen group, preferably chlorine or fluorine, or

[0051] ○OH group, and

[0052] ● k is 1 or an integer from 1 to 10, preferably an integer from 1 to 8, particularly preferably an integer from 1 to 5.

[0053] Preferably, C-1 is a cyclic phosphazene having a proportion of oligomers (trimers) with k = 1 of 50 to 98 mol %, preferably 70 to 90 mol % and more preferably 70 to 85 mol %. More preferably, C-1 is a phenoxyphosphazene (all groups R = phenoxy) (X-1) having a proportion of oligomers with k = 1 of 50 to 98 mol %.

[0054]

[0055] The phosphazenes can be used individually or as a mixture. The radicals R in structure (X) can be identical or different. The radicals R of the phosphazenes are preferably identical. In a further preferred embodiment, only phosphazenes with identical radicals R are used.

[0056] In a preferred aspect, the proportion of tetramers (k=2) is 2 to 50 mol %, preferably 5 to 40 mol %, based on component C-1.

[0057] In a further aspect, the proportion of higher oligophosphazenes (k=3, 4, 5, 6 and 7), based on component C-1, is 0 to 30 mol %, preferably 2 to 25 mol %.

[0058] In a further aspect, the proportion of oligomers having k≧8, based on component C-1, is 0 to 2 mol %, preferably 0.1 to 1 mol %.

[0059] More preferably, component C-1 comprises phenoxyphosphazenes having a proportion of 70 to 85 mol % of trimers (k=1), a proportion of 10 to 20 mol % of tetramers (k=2), a proportion of 6 to 15 mol % of higher oligomeric phosphazenes (k=3, 4, 5, 6 and 7) and 0.1 to 1 mol % of phosphazene oligomers with k≥8, based on component C-1.

[0060] The oligomeric phosphoric acid ester used according to the invention as component C-2 is preferably selected from bisphenol A bis(diphenyl phosphate), resorcinol (diphenyl phosphate), oligomeric solid phosphoric acid esters and mixtures of two or more of the foregoing.

[0061] The flame retardant can be used together with other flame retardants other than those of groups C-1 and C-2. However, it is preferred that no additional flame retardant other than the flame retardants of groups C-1 and / or C-2 be used. The weight % ratio of C-1 to C-2 is 10:90 to 90:10, preferably 25:75 to 75:25, more preferably 30:60 to 60:30.

[0062] Other components

[0063] The thermoplastic composition according to the invention comprises 0 to 5 wt %, preferably 0 to 3 wt %, more preferably up to 2 wt %, of further components, based on the weight of the composition.

[0064] In particular, polytetrafluoroethylene (PTFE) or a composition containing PTFE, such as a masterbatch of PTFE and a polymer or copolymer containing styrene or methyl methacrylate, or SAN-encapsulated PTFE is used as an anti-drip agent. Particularly preferred further components according to the invention contain, in addition to optional further additives, 0.01 to 2% by weight of an anti-drip agent, preferably selected from one or more of PTFE and SAN-encapsulated PTFE, based on the weight of the composition.

[0065] In another aspect, the further component according to the invention comprises 0.01 to 3 wt. % of one or more selected from talc, kaolin, mica, based on the weight of the composition. Preferably, the further component and thus the thermoplastic composition does not comprise talc.

[0066] Other components used in the composition may include flame retardant synergists, lubricants and mold release agents (e.g., pentaerythritol tetrastearate), nucleating agents, stabilizers, antistatic agents (e.g., conductive carbon black, carbon fibers, carbon nanotubes, and organic antistatic agents such as polyalkylene ethers, alkyl sulfonates, or polyamide-containing polymers), acids, fillers, and reinforcing materials (e.g., glass fibers or carbon fibers, mica, kaolin, talc, CaCO3, and glass flakes), and one or more of dyes and pigments.

[0067] Composition

[0068] The combination of specific types and amounts of materials constituting the thermoplastic composition results in a distribution of properties, particularly in terms of FR performance, toughness, stiffness, and flowability. The examples and comparative examples disclosed herein provide the skilled artisan with materials that fall within and outside the scope of the invention, thereby forming a basis for developing additional embodiments according to the invention without undue burden.

[0069] According to the present invention, the thermoplastic composition comprises

[0070] A. 60 to 95% by weight of aromatic polycarbonate,

[0071] B. 3 to 15% by weight of impact modifiers,

[0072] C. 2 to 20% by weight of a flame retardant additive comprising at least one cyclic phosphazene (C-1) and at least one oligomeric phosphoric acid ester (C-2),

[0073] D. 0 to 5% by weight of other components;

[0074] The combined amount of (A) to (D) is 100% by weight.

[0075] In the composition, the amount of aromatic polycarbonate is preferably 70 to 90% by weight. The amount of impact modifier is preferably 2 to 12% by weight. The amount of flame retardant additive is preferably 2 to 15% by weight. The amount of other components is preferably 1 to 3% by weight.

[0076] For the avoidance of doubt, the skilled artisan will appreciate that the total weight of the composition will be 100 wt % and that any combination of materials that do not total 100 wt % is unrealistic and not in accordance with the present invention.

[0077] According to the present invention, the thermoplastic composition is selected to have

[0078] - a notched Izod impact resistance of at least 300 J / m, measured according to ASTM D-256 at a temperature of 23°C;

[0079] - a melt flow rate of at least 7.0 g / 10 min as measured according to ASTM D1238 (300° C., 1.2 kg); and

[0080] - UL94 rating of V0 at 0.75mm thickness.

[0081] The notched Izod impact strength may be 300 to 900 J / m.

[0082] The melt flow rate may be 7.0 to 20.0 g / 10 min, preferably 10.0 to 18.0 g / 10 min, and more preferably 12.0 to 16.0 g / 10 min.

[0083] Preferably, the composition additionally has a heat distortion temperature of at least 90° C., preferably at least 95° C., more preferably at least 100° C., measured according to ASTM D648 standard under a load of 0.45 MPa.

[0084] Preferred ranges for the amounts of the components and preferred ranges for the properties of the composition may be combined without limitation, provided of course that these ranges fall within the bounds of the scope of the invention as defined herein in its broadest form. In other words, preferred ranges for one or more of the amounts and / or types of the components making up the thermoplastic composition may be combined with preferred ranges for one or more of the properties of the thermoplastic composition, and all such combinations are considered as disclosed herein.

[0085] The composition can be manufactured by various methods known in the art. For example, polycarbonate, impact modifier, flame retardant additive and other additives are first blended in a high-speed mixer or by manual mixing. The blend is then fed to the throat of a twin-screw extruder via a hopper. Alternatively, at least one of the components can be directly fed into the extruder at the throat and / or downstream through a side feeder or introduced into the composition by being compounded into a masterbatch with a desired polymer and fed into the extruder. For example, a Krupp Werner & Pfleiderer ZSK2 co-rotating intermeshing 10-barrel twin-screw extruder with a diameter of 25 mm and an L / D ratio of 41 can be used to prepare the composition. The temperature in the extruder can be 180° C. to 265° C. along the screw length. The extrudate can be immediately cooled and granulated in a water bath. The pellets prepared in this way can be 0.6 cm or less in length as required. Such pellets can be used for subsequent molding, shaping or forming.

[0086] Also provided are formed, shaped or molded articles comprising the composition. The composition can be molded into articles by a variety of methods, such as injection molding, extrusion and thermoforming. Some examples of articles include articles for interior or exterior automotive applications and electrical and electronic applications, such as software products (mobile devices, laptops, monitors, tablets, data storage, etc.), computer and (tele)communication applications and across other different fields and applications, such as consumer products and appliances, automotive lighting, under the hood of automobiles, electric vehicle applications, electrical components, electronic displays, energy storage and lighting applications.

[0087] Therefore, the present invention relates to an article comprising or consisting of a composition disclosed herein. More particularly, the present invention relates to the manufacture of an article comprising or consisting of a composition disclosed herein, preferably an automotive component or an electrical or electronic component. Likewise, the present invention relates to a vehicle or an electrical or electronic device comprising said vehicle component or said electrical or electronic component.

[0088] The invention will now be further illustrated based on the following non-limiting examples.

[0089] Test Method

[0090]

[0091] Example

[0092] The samples were molded by injection molding on a L&T ASWA 100T injection molding machine set from 40 to 280° C., the mold temperature setting was maintained at 70° C. for all compositions. The components of the compositions and their sources are listed in Table 1.

[0093] Table 1: Components of the composition and their sources

[0094]

[0095]

[0096]

[0097]

[0098] The amount in Table 2 is the weight percentage based on the total weight of the composition. In all embodiments, the total amount of the component is equal to 100 weight percent. Table 2 shows that the polycarbonate composition (CE1-CE3) comprising an impact modifier and only one type of FR does not show the desired combination of high impact strength and good flammability properties for UL94 V0 at 0.75mm. However, the polycarbonate composition (E1-E4) comprising an impact modifier (ABS or MBS) and a combination of a flame retardant additive containing cyclic phosphazene and oligomeric phosphate does show improved impact properties, especially at room temperature. Together with this, a V0 flame retardancy rating at 0.75mm according to UL94 V0 is achieved. When the composition comprises a polycarbonate prepared by an interfacial method (E3 and E4) or by a melt method (E5 and E6), similar properties can be achieved. Embodiments E7 and E8 include talc or kaolin additives together with an anti-dripping agent TSAN. It can be seen that similar properties can be achieved in the presence of talc or kaolin even with a lower weight % FR additive. In addition to ABS, the addition of a silicone-acrylate composite rubber impact modifier in E9 resulted in a further increase in impact properties compared to E1 while exhibiting similar flame retardant properties.

[0099] Furthermore, it can be seen from Table 2 that among E10, E11 and E12, the impact properties of E11 and E12 are better than E10 while showing comparable flame retardant properties. The composition of E10 contains cyclic phenoxyphosphazene containing only trimers (with k=1), while the composition of E11 contains cyclic phosphazenes containing oligomers of phenoxyphosphazene with up to 8 repeating units (k=1 to k=8). Therefore, the presence of some oligomeric components of phosphazene in the FR additive helps to improve the impact properties in the composition with comparable flame retardant properties. In addition, the HDT and MFR of all the examples are also within acceptable ranges compared to the comparative examples.

Claims

1. A thermoplastic composition comprising, based on the weight of the composition: (A) 60 to 95% by weight of an aromatic polycarbonate, (B) 3 to 15% by weight of an impact modifier, (C) 2 to 20 wt% of a flame retardant additive, the flame retardant additive comprising at least one cyclic phosphazene (C-1) and at least one oligomeric phosphate (C-2) (D) 0 to 5 wt % of other components; in, The combined amount of (A) to (D) is 100% by weight. and wherein the composition has: - a notched Izod impact resistance measured according to ASTM D-256 at a temperature of 23° C. of at least 300 J / m, preferably from 300 to 900 J / m; - a melt flow rate determined according to ASTM D1238 (300° C., 1.2 kg) of at least 7.0 g / 10 min, preferably from 7.0 to 20.0 g / 10 min; and -UL94 rating of V0 at 0.75mm thickness.

2. The thermoplastic composition according to claim 1, wherein the weight % ratio of (C-1) to (C-2) is 10:90 to 90:

10.

3. The thermoplastic composition according to any one of claims 1 to 2, wherein the cyclic phosphazene (C-1) is selected from propoxyphosphazene, phenoxyphosphazene, methylphenoxyphosphazene, aminophosphazene and fluoroalkylphosphazene and a phosphazene having the following structure (X): in, The radicals R are identical or different and are each an amine group; an optionally halogenated, preferably fluorinated C1- to C8-alkyl group, preferably a methyl, ethyl, propyl or butyl group; a C1 to C8 alkoxy group, preferably a methoxy, ethoxy, propoxy or butoxy group; a C5 to C6 cycloalkyl group, which is optionally substituted in each case by an alkyl group, preferably a C1 to C4 alkyl group, and / or a halogen, preferably a chlorine and / or a bromine group; a C6 to C20 aryloxy group, which is optionally substituted in each case by an alkyl group, preferably a C1 to C4 alkyl group, and / or a halogen, preferably a chlorine, a bromine, and / or a hydroxyl group, preferably a phenoxy group, a naphthoxy group; a C7 to C12 aralkyl group, which is optionally substituted in each case by an alkyl group, preferably a C1 to C4 alkyl group, and / or a halogen, preferably a chlorine and / or a bromine group, preferably a phenyl-C1 to C4 alkyl group; or a halogen group, preferably a chlorine group; or an OH group; and k is an integer from 1 to 10, preferably from 1 to 8.

4. The thermoplastic composition according to claim 3, wherein the cyclic phosphazene (C-1) has a proportion of trimers (k=1) of 50 to 98 mol%, preferably 70 to 90 mol% and more preferably 70-85 mol%.

5. Thermoplastic composition according to any one or more of claims 1 to 4, wherein the oligomeric phosphate ester (C-2) is selected from bisphenol A bis(diphenyl phosphate), resorcinol (diphenyl phosphate), oligomeric solid phosphate esters and mixtures of two or more of the foregoing.

6. The thermoplastic composition according to any one or more of claims 1 to 4, wherein the impact modifier is selected from the group consisting of acrylonitrile-butadiene-styrene impact modifiers, methyl methacrylate-butadiene-styrene impact modifiers, ethylene-acrylate copolymer impact modifiers, ethylene-acrylate-glycidol copolymer impact modifiers, and mixtures of two or more of the foregoing.

7. The thermoplastic composition according to claim 5, wherein the impact modifier further comprises 1 to 5 wt% of a silicon-acrylate composite rubber comprising a polyorganosiloxane rubber component and a polyalkyl (meth)acrylate rubber component.

8. Thermoplastic composition according to any one or more of claims 1 to 6, wherein the further component (D) comprises 0.01 to 2 wt. %, based on the weight of the composition, of an anti-drip agent, preferably selected from one or more of PTFE and SAN-encapsulated PTFE.

9. Thermoplastic composition according to any one or more of claims 1 to 7, wherein the further component (D) comprises 0.01 to 3% by weight, based on the weight of the composition, of one or more selected from talc, kaolin, mica.

10. The thermoplastic composition of any one or more of claims 1 to 9, wherein the aromatic polycarbonate comprises two or more aromatic polycarbonates having different melt flow rates.

11. Thermoplastic composition according to any one or more of claims 1 to 10, wherein the aromatic polycarbonate comprises or consists of bisphenol A polycarbonate or a mixture of bisphenol A polycarbonates.

12. The thermoplastic composition of any one or more of claims 1-11, wherein the aromatic polycarbonate has a weight average molecular weight of 15,000 to 60,000 g / mol as determined using gel permeation chromatography with polycarbonate standards.

13. Thermoplastic composition according to any one or more of claims 1 to 12, wherein the composition has a heat distortion temperature of at least 90°C, preferably at least 95°C, measured according to the ASTM D648 standard at a load of 0.45 MPa.

14. Article comprising or consisting of the thermoplastic composition according to any one or more of claims 1 to 13.

15. Use of a thermoplastic composition according to any one or more of claims 1 to 14 for the manufacture of articles, preferably automotive parts, electrical or electronic parts.

Images