POLYCARBONATE COMPOSITION COMPRISING TALC

Abstract

The invention relates to a composition obtainable by mixing polycarbonate, unsized talc and a specific anhydride-modified alpha-olefin polymer, wherein the amounts of the talc and the specific anhydride-modified alpha-olefin polymer are matched to one another such that, for every 10 parts by weight of the talc, 0.10 to 1.4 parts by weight of the anhydride-modified alpha-olefin polymer are used. It has been shown that in situ sizing of talc with the wax can minimize the degradation of the polycarbonate only in the course of mixing with the polycarbonate and, at the same time, properties such as multiaxial impact resistance and flowability can be improved.

Claims

1.-15. (canceled)

16. A composition obtained by mixing at least components A) to C), wherein A) is polycarbonate, B) is unsized talc and C) is at least one anhydride-modified alpha-olefin polymer having an acid number of at least 30 mg KOH/g and a mean molecular weight M.sub.W of 4000 to 40 000 g/mol, where the mean molecular weight M.sub.W is determined by means of gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration and the acid number is determined by means of potentiometric titration with alcoholic potassium hydroxide solution according to DIN ISO 17025:2005, wherein the amounts of B) and C) prior to mixing are matched to one another such that, for every 10 parts by weight of component B), 0.10 to 1.4 parts by weight of component C) are used, and wherein the composition is free of polyesters and graft polymers.

17. The composition according to claim 16, wherein the talc has been compacted.

18. The composition according to claim 16, wherein component C) comprises Ca) 90.0%-98.0% by weight of alpha-olefin polymer and Cb) 2.0%-10.0% by weight of anhydride.

19. The composition according to claim 16, wherein the acid number of component C) is 30 to 110 mg KOH/g.

20. The composition according to claim 16, comprising 50% to 94.9% by weight of component A) and 5.00% to 45.00% by weight of component B).

21. The composition according to claim 16, wherein component A) is selected from at least one from the group of the aromatic homopolycarbonates and copolycarbonates or mixtures thereof.

22. The composition according to claim 16, wherein component A) is a siloxane-containing polycarbonate.

23. The composition according to claim 16, wherein the composition comprises at least one further constituent selected from the group consisting of flame retardants, antidripping agents, thermal stabilizers, demoulding agents, antioxidants, UV absorbers, IR absorbers, antistats, optical brighteners, opacifiers, colorants and/or fillers other than talc.

24. A composition consisting of A) aromatic polycarbonate, B) talc, the talc used being unsized, C) at least one anhydride-modified alpha-olefin polymer having an acid number of at least 30 mg KOH/g and a mean molecular weight M.sub.W of 4000 to 40 000 g/mol, where the mean molecular weight M.sub.W is determined by means of gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration and the acid number is determined by means of potentiometric titration with alcoholic potassium hydroxide solution according to DIN ISO 17025:2005, and optionally one or more additives selected from the group consisting of flame retardants, antidripping agents, thermal stabilizers, demoulding agents, antioxidants, UV absorbers, IR absorbers, antistats, optical brighteners, opacifiers, colorants, wherein the amounts of B) and C) prior to mixing are matched to one another such that, for every 10 parts by weight of unsized talc, 0.10 to 1.4 parts by weight of component C) are used.

25. A process for sizing talc B) by means of at least one anhydride-modified alpha-olefin polymer C) having an acid number, determined by means of potentiometric titration with alcoholic potassium hydroxide solution according to DIN ISO 17025:2005, of at least 30 mg KOH/g and a mean molecular weight M.sub.W of 4000 to 40 000 g/mol, where the mean molecular weight M.sub.W is determined by means of gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration, characterized in that the sizing is effected during the mixing of the talc B) with a polycarbonate A) in the melt.

26. The process according to claim 25, wherein the amounts of B) and C) prior to mixing are matched to one another such that, for every 10 parts by weight of component B), 0.10 to 1.4 parts by weight of component C) are used.

27. The process according to claim 25, wherein 5% to 45% by weight of talc is used.

28. A method comprising utilizing anhydride-modified alpha-olefin polymer having an acid number, determined by means of potentiometric titration with alcoholic potassium hydroxide solution according to DIN ISO 17025:2005, of at least 30 mg KOH/g and a mean molecular weight M.sub.W of 4000 to 40 000 g/mol, where the mean molecular weight M.sub.W is determined by means of gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration, for stabilization of polycarbonate in a composition to which unsized talc has been added, wherein, for every 10 parts by weight of the unsized talc, 0.10 to 1.4 parts by weight of the anhydride-modified alpha-olefin polymer are used.

29. A method comprising utilizing the composition according to claim 16 for production of a moulding, wherein the moulding is a housing or part of a housing in the electronics sector, a housing for mobile electronics, a protective equipment part or a bodywork part in the automotive sector.

30. A moulding comprising the composition according to claim 16.

Description

EXAMPLES

[0194] Materials Used:

[0195] Material A1: a linear bisphenol A polycarbonate having an MVR (300° C./1.2 kg) of 19 cm.sup.3/(10 min) and a mean molecular weight M.sub.w of about 24 000 g/mol from Covestro Deutschland AG.

[0196] Material A2: a linear bisphenol A polycarbonate having an MVR (300° C./1.2 kg) of 9 cm.sup.3/(10 min) and a mean molecular weight M.sub.w of about 28 000 g/mol from Covestro Deutschland AG.

[0197] Material A3: Polysiloxane-polycarbonate block cocondensate with an MVR (300° C.; 1.2 kg) of about 14 cm.sup.3/(10 min) and a polydimethylsiloxane content of about 5% by weight; solution viscosity η.sub.rel 1.26. The block used for preparation of the SiCoPC corresponds to the formula (11);

[0198] Material 3: preparation of the polysiloxane-polycarbonate block cocondensate:

[0199] Starting Materials:

[0200] Polycarbonate:

[0201] The starting material used for the reactive extrusion is linear bisphenol A carbonate having end groups based on phenol with a melt volume index of 59-62 cm.sup.3/(10 min) (measured at 300° C. with load 1.2 kg according to ISO 1133 (2011)). This polycarbonate does not contain any additives such as UV stabilizers, demoulding agents or thermal stabilizers. The polycarbonate was prepared via a melt transesterification process as described in DE 102008019503. The polycarbonate has a content of phenolic end groups of about 600 ppm.

[0202] Siloxane Block:

[0203] Hydroquinone-terminated polydimethylsiloxane of the formula (11) with n of about 30 and m in the range from 3 to 4 (R1=H, R2=methyl), with a hydroxyl content of 12 mg KOH/g and a viscosity of 370 mPa.Math.s (23° C.); the sodium content is about 1.5 ppm.

[0204] Catalyst:

[0205] The catalyst used is tetraphenylphosphonium phenoxide from Rhein Chemie Rheinau GmbH (Mannheim, Germany) in the form of a masterbatch. Tetraphenylphosphonium phenoxide is used in the form of cocrystals with phenol and contains about 70% tetraphenylphosphonium phenoxide. The amounts which follow are based on the substance obtained from Rhein Chemie (as cocrystals with phenol).

[0206] The masterbatch is produced as a 0.25% mixture. For this purpose, 18 g of tetraphenylphosphonium phenoxide are spun onto 4982 g in a drum hoop mixer for 30 minutes. The masterbatch is metered in in a ratio of 1:10, such that the catalyst is present with a proportion of 0.025% by weight in the overall amount of polycarbonate.

[0207] The block cocondensate is prepared from the polycarbonate component and the siloxane component via a reactive extrusion process according to WO 2015/052110 A1.

[0208] Sodium content: The sodium content is determined via mass spectrometry with inductively coupled plasma (ICP-MS).

[0209] Material B1: compacted talc having a content of 98% by weight, an iron oxide content of 1.9% by weight, an aluminium oxide content of 0.2% by weight, ignition loss (DIN 51081/1000° C.) of 5.4% by weight, pH (to EN ISO 787-9:1995) of 9.15, D50 (sedimentation analysis) of 2.2 μm; BET surface area according to ISO 4652:2012 of 10 m.sup.2/g, brand: Finntalc M05SLC, manufacturer: Mondo Minerals B. V.

[0210] Material B2: compacted talc having a content of 99% by weight, an iron oxide content of 0.4% by weight, an aluminium oxide content of 0.4% by weight, ignition loss of 6.0% by weight, pH (to EN ISO 787-9:1995) of 9.55, D50 (sedimentation analysis) of 0.65 μm; BET surface area: 13.5 m.sup.2/g, brand: HTP Ultra5c, manufacturer: Imifabi.

[0211] Material C1: ethylene-propylene-octene terpolymer with maleic anhydride (ethylene:propylene:octene 87:6:7 (weight ratio)), CAS No. 31069-12-2, with molecular weight (gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration) M.sub.w=6301 g/mol, M.sub.n=1159 g/mol, density 940 kg/m.sup.3, acid number 53 mg KOH/g, maleic anhydride content 4.4% by weight, based on the terpolymer C1.

[0212] Material C2: ethylene-propylene-octene terpolymer with maleic anhydride having a mean molecular weight (gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration) M.sub.w=14 400 g/mol, M.sub.n=1880 g/mol, acid number 23 mg KOH/g.

[0213] Material C3: propylene-maleic anhydride polymer having a mean molecular weight (gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration) M.sub.w=170 300 g/mol, M.sub.n=10 100 g/mol, acid number 6 mg KOH/g.

[0214] Material C4: HD polyethylene-maleic anhydride polymer having a mean molecular weight (gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration) M.sub.w=153 500 g/mol, M.sub.n=18 500 g/mol, acid number 0 mg KOH/g.

[0215] Material C5: propylene-maleic anhydride polymer having a mean molecular weight (gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration) M.sub.w=20 700 g/mol, M.sub.n=1460 g/mol, acid number 78 mg KOH/g.

[0216] Material C6: propylene-ethylene-maleic anhydride copolymer having a mean molecular weight (gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration) M.sub.w=20 670 g/mol, M.sub.n=2081 g/mol, acid number 46 mg KOH/g.

[0217] Material C7: ethylene-octene-maleic anhydride copolymer having a mean molecular weight (gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration) M.sub.w=196 000 g/mol, M.sub.n=13 140 g/mol, acid number 0.2 mg KOH/g.

[0218] Material C8: HD ethylene-maleic anhydride polymer having a mean molecular weight (gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration) M.sub.w 32 96 550 g/mol, M.sub.n=6258 g/mol, acid number 5 mg KOH/g.

[0219] Material D: titanium dioxide, sized titanium dioxide, Kronos® 2230 (Kronos Titan GmbH, Germany).

[0220] All acid numbers of components C1 to C8 were determined according to DIN ISO 17025:2005 by Currenta GmbH & Co. OHG, Leverkusen, via potentiometric titration with alcoholic potassium hydroxide solution.

[0221] Melt volume flow rate (MVR) was determined in accordance with ISO 1133-1:2012 at a test temperature of 300° C., mass 1.2 kg, using a Zwick 4106 instrument from Zwick Roell. The abbreviation MVR stands for the starting melt volume flow rate (after 4 minutes preheating time), and the abbreviation IMVR stands for melt volume flow rate after 19 min.

[0222] Relative solution viscosity “eta rel”/“η.sub.rel” was determined by double determination according to ISO1628-1:2009 with an Ubbelohde viscometer in a concentration of 5 g/l in dichloromethane. The FIGURES reported hereinafter are always the mean values for the relative solution viscosity.

[0223] Characteristics from the puncture impact experiment (multiaxial impact resistance) were determined at 23° C. according to DIN EN ISO 6603-2:2002 on test specimens of dimensions 60 mm×60 mm×2 mm.

[0224] Charpy impact resistance was measured according to ISO 179/1eU (2010 version) on single-side-injected test bars measuring 80 mm×10 mm×4 mm at 23° C.

[0225] Charpy notched impact resistance was measured according to ISO 179/1eA (2010 version) on test specimens of geometry 80 mm×10 mm×4 mm at 23° C.

[0226] Vicat softening temperature VST/B50 was determined as a measure of heat distortion resistance to ISO 306 (2014 version) on test specimens of dimensions 80 mm×10 mm×4 mm with a die load of 50 N and a heating rate of 50° C./h with the Coesfeld Eco 2920 instrument from Coesfeld Material test.

[0227] Modulus of elasticity and elongation at break were measured according to ISO 527 (1996 version) on single-site-injected dumbbell bars having a core of dimensions 80 mm×10 mm×4 mm at 23° C.

[0228] The comparison of the flowability of the thermoplastic moulding compounds was made in each case against the pure component A used in the moulding compounds: the flow path of component A was set to a defined flow length in the mould used (cavity: 2 mm×8 mm×1000 mm). The moulding compounds to be compared were then processed with constant injection moulding parameters (including melt temperature, mould temperature, injection time, injection speed). The moulding was ejected without any further period under hold pressure. The flow length of a moulding compound achieved is the average from 5 flow spirals, where the deviation in a series of flow spirals must not be more than ±10 mm. The flow length achieved is reported as a percentage ratio to the flow length of component A previously established.

[0229] Thermal conductivity was determined according to ASTM E1461 (2013 version, Nanoflash method).

[0230] The coefficient of linear thermal expansion (CLTE) was determined according to DIN 53752-1980-12.

[0231] Fire characteristics are measured according to UL 94 V on bars of dimensions 127 mm×12.7 mmדreported in the table mm”.

[0232] The components specified in the tables which follow were compounded either in a twin-screw extruder (Tables 1, 2, 4-6) or in a co-kneader (Tables 3 and 3a), with addition of components B) only at a later stage to components A), C) and optionally D) that have already been melted or dispersed in the melt. C) and D) were metered in simultaneously with A) or immediately after the melting of component A). The compounding was effected within a temperature range from 260° C. to 340° C., based on the melting temperature of component A). Temperatures of 280° C. to 330° C. were used in the twin-screw extruder, and temperatures of 260-280° C. in the co-kneader.

[0233] The tables which follow show the compositions and respective results.

TABLE-US-00001 TABLE 1 Stabilization of the composition (experiments 1 to 9 (inventive) and comparative experiments V1 to V8) Component V1 1 2 3 4 5 V2 V3 V4 (A2) % by wt. 79.90 79.75 79.50 79.25 79.00 78.00 77.00 100.00 77.00 (B1) % by wt. 20.00 20.00 20.00 20.00 20.00 20.00 20.00 20.00 20.00 (C1) % by wt. 0.10 0.25 0.50 0.75 1.00 2.00 3.00 (C2) % by wt. 1.00 2.00 (C5) % by wt. Method Unit MVR cm.sup.3/(10 min) 27.0 17.3 10.2 8.8 7.7 6.8 7.1 14.2 10.7 IMVR cm.sup.3/(10 min) 26.6 23.9 17.5 12.7 10.4 8.1 8.5 19.9 13.6 Relative solution 1.207 1.227 1.250 1.261 1.261 1.264 1.267 1.218 1.241 viscosity Puncture impact experiment Maximum N 1587 2593 3887 4316 4304 4151 1699 3664 1553 force [Fm] Energy at J 3.4 8.1 21.7 29.1 29.3 28.4 4.8 22.4 4 maximum force [Wm] Total J 4.0 9.4 23.8 31.5 31.9 31 10.1 24.4 7.4 energy [Wp] Total mm 5.6 7.7 11.9 13.9 14 14.2 10.4 12.1 8.7 deformation [Sp] Charpy kJ/m.sup.2 55 65 123 185 209 215 296 176 235 VICAT ° C. 141.6 141.9 143.3 143.6 143.8 143.5 143.0 143.0 143.9 temperature Tensile test Modulus of MPa 4629 4786 4723 4712 4834 4602 4388 4635 4173 elasticity (1 mm/min) Tensile stress at MPa 66 64.4 61.4 60.4 59.5 56.3 54.7 58.1 55.5 yield (5 mm/min) Tensile strain at % 3.6 3.6 3.8 4.0 3.9 4.0 4.1 3.9 4.1 yield (5 mm/min) Tensile stress at MPa 65.8 62.5 54.7 50.2 47.5 37.4 27.1 49.2 44.6 break (5 mm/min) Tensile strain at % 3.5 4.6 6.4 7.9 8.3 10.2 10 9 20.5 break (5 mm/min) Nominal % 3 4 5 5 6 7 6 6 12 elongation at break (5 mm/min) Component V5 V6 6 7 8 9 V7 V8 (A2) % by wt. 100.00 79.90 79.75 79.50 79.25 79.00 80.00 100.00 (B1) % by wt. 20.00 20.00 20.00 20.00 20.00 20.00 20.00 (C1) % by wt. (C2) % by wt. 3.00 (C5) % by wt. 0.10 0.25 0.50 0.75 1.00 Method Unit MVR cm.sup.3/(10 min) 8.0 25.5 13.0 9.3 7.9 7.2 25.7 8.7 IMVR cm.sup.3/(10 min) 9.3 32.3 21.3 13.7 10.3 9.0 25.2 8.9 Relative solution 1.263 1.206 1.240 1.257 1.269 1.270 1.207 1.288 viscosity Puncture impact experiment Maximum N 1490 1778 3763 4498 4415 4496 1234 5471 force [Fm] Energy at J 4.7 4.0 19.7 31.5 30.4 32.6 2.4 56.6 maximum force [Wm] Total J 8.8 4.8 21.4 33.8 33.0 35.3 2.9 59.2 energy [Wp] Total mm 10.3 5.9 11.0 14.1 14.1 14.7 5.2 19.5 deformation [Sp] Charpy kJ/m.sup.2 254 57 78 159 201 249 48 VICAT ° C. 142.6 141.0 143.0 144.5 145.3 145.2 141.8 145.1 temperature Tensile test Modulus of MPa 3975 4703 4898 4773 4928 4895 4686 2352 elasticity (1 mm/min) Tensile stress at MPa 53.4 66.6 64.8 62.6 61.6 60.6 0 61.5 yield (5 mm/min) Tensile strain at % 4.4 3.8 3.7 3.9 3.9 4.0 0 6.1 yield (5 mm/min) Tensile stress at MPa 47.3 65.5 60.5 53.8 49.6 43.7 66.1 67.3 break (5 mm/min) Tensile strain at % 12.5 4.5 5.5 6.9 8.4 11.1 3.4 113.6 break (5 mm/min) Nominal % 8 4 4 5 6 7 3.0 94 elongation at break (5 mm/min)

[0234] Table 1 shows that, depending on the acid number and the amount of component C used, the relative solution viscosity of component A can be stabilized in spite of the presence of component B: the more component C is added and the higher the acid number of component C, the more the solution viscosity approaches the level of the pure component A (V8). The relative solution viscosity of component A) is typically between 1.275 and 1.290. If component C) is absent, the solution viscosity of A) is noticeably lowered (V7).

[0235] The observed stabilization of the relative solution viscosity is also manifested by lowering of the MVR and IMVR, and in a smaller difference between IMVR and MVR. The more component C is added and the higher the acid number of component C, the more MVR and IMVR approach the level of the pure component A (V8), and the smaller the difference between IMVR and MVR becomes, which indicates significant attenuation of the molecular weight-reducing reactions at temperature. A noticeable effect on MVR and IMVR only occurs from concentrations of component C) of 0.10 part by weight to 10 parts by weight of component B) (comparison of experiments V7, V8 and V1 with 1 or of V6 with 6).

[0236] The use of component C) additionally achieves a significant improvement in the toughness of the moulding compound from 0.10 part by weight of component C) per 10 parts by weight of component B). From concentrations of 1.5 parts by weight of component C) per 10 parts by weight of component B), however, there is a deterioration in puncture impact resistance (multiaxial impact resistance) (puncture impact test; comparison of experiments 5 and V2).

[0237] If, moreover, the acid number of component C) is below 30 mg KOH/g, stabilization of the solution viscosity and lowering of the MVR/IMVR are achieved only at higher concentrations of C) (see experiments V3 and V4 compared to V5 and to 4, 5 and 9), although these higher concentrations of C) in turn have an adverse effect on puncture impact resistance.

[0238] In virtually all the experiments, it is apparent that good Charpy impact resistance is achieved. However, it also becomes clear that, on the basis of this Charpy impact resistance, no conclusions can be drawn about the multiaxial impact resistance in the puncture impact experiment. These are surprisingly at a high level for the experiments according to the invention only.

[0239] Moreover, it can also be seen that the Vicat temperature, within the range of contents of component C) according to the invention, approaches the Vicat temperature of the pure component A) (experiment V8). The higher the acid number and the higher the molecular weight of component C), and the closer the relative solution viscosity to the relative solution viscosity of the pure component A given the same amount of component C), the more marked this tendency is.

[0240] Overall, it can thus be inferred from Table 1 that only specific waxes C) having specific acid numbers and molar masses are suitable for achieving a good balance between solution viscosity, Vicat temperature, reinforcement (modulus of elasticity) and multiaxial impact resistance. Especially for multiaxial impact resistance and a high Vicat temperature, the concentration of component C) has an upper limit. If too much of component C) is added, there is a deterioration in multiaxial puncture impact, Vicat temperature and modulus of elasticity; Table 1 experiments 1-5 and 6-9 versus V2-V5, especially 4-5 and 9 versus V3-V4.

TABLE-US-00002 TABLE 2 Comparison of different waxes C) (experiments 10 to 12 (inventive) and comparative examples V9 to V12) Component 10 V9 V10 11 12 V11 V12 (A1) % by wt. 79.00 79.00 79.00 79.00 79.00 79.00 79.00 (B1) % by wt. 20.00 20.00 20.00 20.00 20.00 20.00 20.00 (C1) % by wt. 1.00 (C3) % by wt. 1.00 (C4) % by wt. 1.00 (C5) % by wt. 1.00 (C6) % by wt. 1.00 (C7) % by wt. 1.00 (C8) % by wt. 1.00 Method Unit MVR cm.sup.3/(10 min) 12.7 28.5 19.9 12.1 15.0 17.4 16.9 Puncture impact experiment Maximum N 3286 935 706 3157 3123 1004 922 force [Fm] Energy at J 16 1.9 1.7 13.3 12.8 2.1 2 maximum force [Wm] Total J 18.7 2.6 2.3 15.2 14.6 2.8 2.8 energy MTN Total mm 11.5 5.2 5.7 9.9 9.7 5.5 5.6 deformation [Sp] Charpy kJ/m.sup.2 108 44 41 93 93 58 47 VICAT B ° C. 144.0 142.0 140.8 146.4 144.8 140.7 141.7

[0241] As can be inferred from Table 2, different components C) lead to different results in the puncture impact experiment. The comparison in Table 2 makes it clear that only with the components C1), C5) and C6) according to the invention having acid number and molar mass according to the invention are good multiaxial impact resistances achieved in combination with high Vicat temperature.

TABLE-US-00003 TABLE 3 Properties of the compositions (experiments 13 to 16 (inventive)) Component 13 14 15 16 (A1) % by wt. 89.50 79.00 68.50 58.00 (B1) % by wt. 10.00 20.00 30.00 40.00 (C1) % by wt. 0.50 1.00 1.50 2.00 Method Conditions Unit MVR cm.sup.3/(10 min) 16.1 13.3 9.7 6.4 Flow path Flow distance % 106 108 108 108 versus A1) VICAT B ° C. 143.9 143.4 144.0 143.3 Thermal conductivity in plane W/(mK) 0.335 0.563 0.965 1.372 through plane W/(mK) 0.217 0.228 0.25 0.282 CLTE parallel ppm/K 51.74 42.04 36.92 30.75 transverse ppm/K 59.24 55.52 52.1 52.15 Puncture impact experiment Maximum force [Fm] N 2591 683 Energy at maximum force [Wm] J 10.4 2.3 Total energy [Wp] J 12.2 3.3 Total deformation [Sp] mm 9.4 6.4 Charpy kJ/m.sup.2 83.5 20.1

TABLE-US-00004 TABLE 3a Examples 15 and 16 with titanium dioxide: Component 15a 16a (A1) % by wt. 66.50 56.00 (B1) % by wt. 30.00 40.00 (C1) % by wt. 1.50 2.00 (D) % by wt. 2.00 2.00 Method Unit MVR cm.sup.3/10 min 9.4 4.6 IMVR cm.sup.3/10 min 11.2 5.8 Relative solution viscosity 1.254 1.255 Puncture impact experiment Maximum force [Fm] N 2924 670 Energy at maximum force [Wm] J 13.2 2.2 Total energy [Wp] J 15.5 3.2 Total deformation [Sp] mm 10.8 6.9 Charpy kJ/m.sup.2 78 20 VICAT temperature ° C. 144.4 144.6 Tensile test Modulus of elasticity (1 mm/min) MPa 5866 7176 Tensile stress at yield (5 mm/min) MPa 51.6 0 Tensile strain at yield (5 mm/min) % 2.9 0 Tensile stress at break (5 mm/min) MPa 49.5 44.8 Tensile strain at break (5 mm/min) % 3.6 1.3 Nominal elongation at break (5 mm/min) % 3 1 Thermal conductivity in plane, W/(mK) 0.91 1.41 through plane, W/(mK) 0.23 0.28 CLTE parallel, ppm/K 35.24 31.88 transverse, ppm/K 54.03 51.20

[0242] As can be inferred from Table 3, the flow path covered by compositions 13 to 16 in the flow spiral is always constantly higher than the flow path of the pure polycarbonate A, even though the person skilled in the art, on consideration of the MVR values, would actually expect the flowability to fall with rising content of component B). Even in the case of 50% by weight of B), very good flow paths can still be achieved. Inventive examples 13-16 additionally have a unique combination of high flowability and high filler content, with achievement of additional advantageous properties such as thermal conductivity and heat distortion resistance via the filler content. Surprisingly, in spite of addition of component C) which is adsorbed onto the surface of the talc particles, it is nevertheless possible to achieve excellent thermal conductivities of up to 2 W/(mK), based on the area of the injection moulding according to ASTM E 1461:2013. Toughness in the puncture impact experiment remains at a high level in spite of a significant filler content of 30% or 40% by weight of component B) (Examples 15 and 16).

TABLE-US-00005 TABLE 4 Properties of the compositions (experiments 17 and 18 (inventive)) Component 17 18 (A2) % by wt. 77.00 100.00 (B1) % by wt. 20.00 (Cl) % by wt. 1.00 (D) % by wt. 2.00 Method Conditions Unit MVR cm.sup.3/(10 min) 8.7 8.7 Flow path Flow distance versus A2) % 115 100

[0243] It can be seen from Table 4 that the improvement in flow path in the case of a more viscous polycarbonate (A2) is much clearer than in the case of a polycarbonate having lower viscosity (comparison with Table 3). Again, there is no correlation of the improved flow path with the MVR obtained.

TABLE-US-00006 TABLE 5 Stabilization of a filled polysiloxane-polycarbonate block cocondensate (experiment 19 (inventive) and comparative experiment V13) Component V13 19 (A3) % by wt. 80.00 79.00 (B2) % by wt. 20.00 20.00 (C1) % by wt. 1.00 Method Conditions Unit MVR cm.sup.3/(10 min) 39.1 6.7 IMVR cm.sup.3/(10 min) 39.3 8.4 Relative solution viscosity 1.189 1.267 Puncture impact experiment Maximum force [Fm] N 745 3282 Energy at maximum force [Wm] J 1.2 17.4 Total energy [Wp] J 1.7 21.6 Total deformation [Sp] mm 4.8 13 Charpy 23° C. kJ/m.sup.2 45 157 VICAT B 50 K/h ° C. 140.3 141.9 23° C. Tensile test Modulus of elasticity (1 mm/min) MPa 4341 4005 Tensile stress at yield (5 mm/min) MPa 0 51.4 Tensile strain at yield (5 mm/min) % 0 3.8 Tensile stress at break (5 mm/min) MPa 59.7 32.6 Tensile strain at break (5 mm/min) % 2.8 14.2 Nominal elongation at break (5 mm/min) % 3 9

[0244] The results in Table 5 demonstrate that, even using a polysiloxane-polycarbonate block cocondensate as component A), stabilization occurs through the inventive in situ sizing of the talc B) by component C1), which becomes apparent from a higher relative solution viscosity and a lower MVR and IMVR. A significant improvement in (multiaxial) impact resistance is also achieved by means of component C) according to the invention.