MULTILAYER BODY, COMPRISING A SUBSTRATE LAYER CONTAINING POLYCARBONATE, TALC AND WAX

Abstract

The invention relates to a multilayer body comprising at least one substrate layer, a metal layer bonded directly thereto and optionally at least one protective layer atop the metal layer, wherein the substrate layer comprises a composition which is obtained by mixing polycarbonate, talc and a specific wax. It was shown that the multilayer bodies obtained are particularly suitable for use as reflectors and (housing) components for light sources and heat sources and displays.

Claims

1.-15. (canceled)

16. A multilayer body comprising I) a substrate layer (S), II) a metal layer (M) bonded directly thereto and III) optionally a protective layer (P) atop the metal layer, wherein the substrate layer comprises a composition obtained by mixing components A) to D), wherein A) is a polycarbonate, B) is an unsized talc having a median particle diameter D50 of 0.01 to 9.5 μm, where the particle diameter D50 is determined by sedimentation analysis, C) is at least one anhydride-modified alpha-olefin polymer having an acid number of at least 30 mg KOH/g, determined by means of potentiometric titration with alcoholic potassium hydroxide solution according to DIN ISO 17025:2005, and an average molecular weight MW of 4000 to 40 000 g/mol, where the average molecular weight MW is determined by means of gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration, and optionally D) a portion of the amount of component B) may be replaced by at least one further filler selected from the group consisting of an expanded graphite having a particle diameter D50 of less than 800 μm or a mixture of the aforementioned expanded graphite with unexpanded graphite and a boron nitride as further filler, where, in the case of graphite, up to 8 parts by weight of the amount of component B) may be replaced and where, in the case of boron nitride, up to 15 parts by weight of the amount of component B) may be replaced, wherein the amounts of components B) and C) prior to mixing with component C) 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 graft polymers and polyesters.

17. The multilayer body according to claim 16, wherein the amount of B) is 12% to 45% by weight, based on the overall composition.

18. The multilayer body according to claim 16, wherein the amount of B) is 18% to 35% by weight, based on the overall composition.

19. The multilayer body according to claim 16, 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), 0.25 to 1.4 parts by weight of component C) are used.

20. The multilayer body according to claim 16, wherein the talc or talc mixture of component B) has a pH of 8 to 10, wherein the pH of the talc or talc mixture is determined according to EN ISO 787-9:1995.

21. The multilayer body according to claim 16, wherein component B) has a median particle diameter D50 of 0.5 to 3.0 μm, wherein the particle diameter D50 is determined by sedimentation analysis.

22. The multilayer body according to claim 16, wherein component B) has a BET surface area of 7.5 to 20.0 m.sup.2/g.

23. The multilayer body according to claim 16, wherein the substrate layer has a thickness of 0.1 mm to 6.0 mm, the metal layer a thickness of 10 nm to 1000 nm, and the optional protective layer a thickness of 5 nm to 200 nm.

24. The multilayer body according to claim 16, wherein the metal layer comprises at least one metal which is selected from the group consisting of aluminium, silver, chromium, titanium and palladium.

25. The multilayer body according to claim 16, wherein the metal layer comprises silver or aluminium.

26. The multilayer body according to claim 16, wherein, if graphite is present as component D), 2 to 7 parts by weight of the amount of component B) are replaced, and wherein, if boron nitride is present as component D), 2 to 12 parts by weight of the amount of component B) are replaced.

27. An article comprising the multilayer body according to claim 16, wherein the article is selected from the group consisting of reflectors, components of light sources, and components of heat sources.

28. A process for producing the multilayer body according to claim 16, comprising the steps of a) forming the substrate layer by injection moulding or extrusion of the composition, at least comprising components A) to C), optionally comprising component D), b) applying the metal layer to the layer obtained in step (a) in a plasma process and c) optionally applying at least one further layer, and d) optionally applying the protective layer to the layer obtained in step (b) or (c).

29. A method comprising providing at least one anhydride-modified alpha-olefin polymer C) having an acid number of at least 30 mg KOH/g and an average molecular weight M.sub.W of 4000 to 25 000 g/mol, wherein the average molecular weight M.sub.W is determined by means of gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration, for production of a substrate layer of a multilayer body, wherein the multilayer body comprises at least the one substrate layer, a metal layer bonded directly thereto and optionally at least one layer atop the metal layer, and wherein the substrate layer comprises a composition which is obtained by mixing at least components A) to D), wherein A) is a polycarbonate and B) is an unsized talc, and optionally C) a portion of the amount of component B) may be replaced by at least one further filler selected from the group consisting of an expanded graphite having a particle diameter D50 of less than 800 μm or a mixture of the aforementioned expanded graphite with unexpanded graphite and a boron nitride as further filler.

30. The method according to claim 29, 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), 0.25 to 1.4 parts by weight of component C) are used.

Description

EXAMPLES

[0265] Materials Used:

[0266] PC1: a linear bisphenol A polycarbonate having an average molecular weight Mw of about 31 000 g/mol from Covestro Deutschland AG and a softening temperature (VST/B 120 to ISO 306:2014-3) of 150° C., which does not contain any UV absorber. The melt volume flow rate (MVR) to ISO 1133:2012-03 is 6.0 cm.sup.3/(10 min) at 300° C. with a 1.2 kg load.

[0267] PC2: a commercially available copolycarbonate based on bisphenol A and bisphenol TMC from Covestro Deutschland AG, having an MVR of 18 cm.sup.3/10 min at 330° C. and a load of 2.16 kg and a softening temperature (VST/B 120 to ISO 306:2014-3) of 183° C.

[0268] PC3: a linear bisphenol A polycarbonate having an average molecular weight Mw of about 24 000 g/mol from Covestro Deutschland AG and a softening temperature (VST/B 120 to ISO 306:2014-3) of 148° C., which does not contain any UV absorber. The melt volume flow rate (MVR) to ISO 1133:2012-03 is 19.0 cm.sup.3/(10 min) at 300° C. with a 1.2 kg load.

[0269] B1 (inventive): compacted unsized talc having a talc 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 to ISO 13317-3:2001) of 0.65 μm; BET surface area: 13.5 m.sup.2/g, brand: HTP Ultra5c, manufacturer: Imifabi.

[0270] B2 (inventive): compacted unsized talc having a talc 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 to ISO 13317-3:2001) of 2.2 μm; BET surface area to ISO 4652:2012: 10 m.sup.2/g, brand: Finntalc M05SLC, manufacturer: Mondo Minerals B. V.

[0271] B3 (comparative): non-compacted unsized talc having a talc content of 98% by weight, an iron oxide content of 2.0% 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 9.1, D50 (sedimentation analysis to ISO 13317-3:2001) of 10 μm; BET surface area to ISO 4652:2012: 3.5 m.sup.2/g, brand: Finntalc M30SL, manufacturer: Mondo Minerals B. V.

[0272] 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) Mw=6301 g/mol, Mn=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.

[0273] C2: propylene-maleic anhydride polymer having an average molecular weight (gel permeation chromatography in ortho-dichlorobenzene at 150° C. with polystyrene calibration) Mw=20 700 g/mol, Mn=1460 g/mol, acid number 78 mg KOH/g. E: titanium dioxide, sized titanium dioxide, brand: Kronos® 2230, manufacturer: Kronos Titan GmbH, Germany.

[0274] D1 (inventive): highly crystalline boron nitride powder (mix of platelets and agglomerates) having a D50 of 16 μm (laser diffraction to ISO 13320:2009); BET surface area (to ISO 4652:2012) of 8.0 m.sup.2/g, brand: CF600, manufacturer: Momentive Performance Materials Inc.

[0275] D2 (comparative): highly conductive expanded graphite powder having a D50≥800 μm and a carbon content ≥98%, brand: Sigratherm® GFG 900, manufacturer: SGL CARBON GmbH.

[0276] D3 (inventive): compacted expanded graphite (powder) having a D50 of 38 μm (laser diffraction to ISO 13320:2009), a carbon content ≥99%, a BET surface area (to ISO 9277:2010) of 25.0 m.sup.2/g, brand: TIMREX® C-Therm001, manufacturer: Imerys Graphite & Carbon Switzerland Ltd.

[0277] F: customary additives, such as thermal stabilizers, in the examples Irganox© B 900 from BASF Lampertheim GmbH.

[0278] The acid numbers of components C1 and C2 were determined according to DIN ISO 17025:2005 by Currenta GmbH & Co. OHG, Leverkusen, via potentiometric titration with alcoholic potassium hydroxide solution.

[0279] 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, or 330° C. and 2.16 kg, using a Zwick 4106 instrument from Zwick Roell. The abbreviation MVR here represents the initial melt volume flow rate (after a preheating time of 4 minutes).

[0280] 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.

[0281] As a measure of thermal stability/heat distortion resistance, the Vicat softening temperature VST/B50 or VST/B120 was determined according to ISO 306 (2014 version) on 80 mm×10 mm×4 mm test specimens with a needle load of 50 N and a heating rate of 50° C./h or 120° C./h using a Coesfeld Eco 2920 instrument from Coesfeld Materialtest.

[0282] Thermal conductivity was determined on injection-moulded test specimens of dimensions 60×60×2 mm to ASTM E 1461 (2013 version, Nano Flash method).

[0283] Coefficient of linear thermal expansion (CLTE) was determined on an injection-moulded test specimen having dimensions of 10×10×4 mm to DIN 53752 (1980-12) with a Mettler Toledo TMA/SDTA 1+ instrument.

[0284] Surface quality was determined visually on injection-moulded parts having dimensions of 150×105×3 mm. The surface of the test specimens rated as poor was one that had an average on the surface of the test specimens (150×105 mm) of more than 10 defects clearly apparent to the eye (bumps, “spots” or “blisters”, depressions, agglomerates).

[0285] Shear viscosities or melt viscosities were ascertained according to ISO 11443 Method A2 at a temperature of 300° C. with a VISCORobo instrument from Göttfert Werkstoff-Prüfmaschinen GmbH.

TABLE-US-00001 TABLE 1 Components/Example V1 1 2 3 V2 4 5 6 V3 7 V4 PC1 PC2 PC3 89.50 79.00 68.50 58.00 47.50 74.00 69.00 79.00 69.00 66.50 66.50 B1 B2 10.00 20.00 30.00 40.00 50.00 20.00 20.00 10.00 10.00 30.00 B3 30.00 C1 0.50 1.00 1.50 2.00 2.50 1.00 1.00 1.00 1.00 1.50 1.50 C2 D1 5.00 10.00 10.00 20.00 D2 D3 E 2.00 2.00 F visual assessment of good good good good poor good good good poor good poor a 150 × 105 × 3 mm injection moulding melt viscosity to [s.sup.−1] ISO 11443 at 300° C. 50 Pas 248 261 324 385 245 316 370 363 500 326 456 100 Pas 249 247 295 339 186 302 340 347 447 292 404 200 Pas 242 221 256 294 154 276 306 320 402 261 350 500 Pas 211 183 186 225 120 227 246 267 315 210 270 1000 Pas 177 157 149 172 98 183 195 216 248 168 209 1500 Pas 159 141 133 146 85 158 168 185 209 146 176 5000 Pas 96 90 84 80 54 89 93 101 112 83 98 Charpy impact 23° C. kJ/m.sup.2 249 171 84 20 8 43 33 54 27 78 35 resistance to ISO179/1eU VICAT B to ISO 50 K/h ° C. 143.9 143.4 144.0 143.3 142.9 145.4 146.0 146.2 146.7 144.4 144.2 306 at 50 K/h Thermal conductivity in-plane W/mK 0.34 0.56 0.97 1.37 1.83 0.84 1.20 0.82 1.65 0.91 0.94 to ASTM E 1461 through- W/mK 0.22 0.23 0.25 0.28 0.32 0.30 0.30 0.28 0.38 0.23 0.25 at 23° C. plane Coefficient of linear parallel ppm/K 51.7 42.0 36.9 30.8 34.8 39.4 36.6 42.8 34.1 35.2 37.5 thermal expansion trans- ppm/K 59.2 55.5 52.1 52.2 43.4 53.8 52.9 56.3 49.4 64.0 54.0 (CLTE) to DIN 53752 verse

TABLE-US-00002 TABLE 2 Components/Example 8 9 V5 10 V6 11 12 V7 V8 V9 V10 PC1 71.8 8.8 PC2 63.0 PC3 78.8 73.8 73.8 71.8 71.8 68.8 68.8 88.8 88.8 B1 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 B2 B3 C1 C2 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 1.0 D1 D2 5.0 7.0 10.0 10.0 D3 5.0 7.0 7.0 7.0 10.0 10.0 E F 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2 visual assessment of good good poor good poor good good poor poor poor poor a 150 × 105 × 3 mm injection moulding melt viscosity to [s.sup.−1] ISO 11443 at 300° C. 50 Pas 244 442 460 571 533 1165 1179 625 707 496 668 100 Pas 228 369 397 469 442 884 983 476 549 429 602 200 Pas 218 305 332 378 363 691 772 380 424 362 507 500 Pas 185 230 256 279 273 494 563 277 309 285 368 1000 Pas 154 182 203 216 213 373 418 215 237 222 273 1500 Pas 138 157 175 183 182 309 349 183 200 186 229 5000 Pas 82 89 98 100 100 149 169 100 108 107 123 Charpy impact 23° C. kJ/m.sup.2 138 24 20 22 18 16 13 13 14 25 33 resistance to ISO179/1eU VICAT B to ISO 50 K/h ° C. 144.0 145.1 145.0 145.9 145.0 143.5 172.1 145.2 146.2 144.5 146.0 306 at 50 K/h Thermal in-plane W/mK 0.61 1.52 1.53 1.93 2.03 2.64 2.16 3.52 3.39 1.47 1.21 conductivity to through- W/mK 0.22 0.33 0.33 0.34 0.35 0.35 0.31 0.46 0.45 0.39 0.40 ASTM E plane 1461 at 23° C. Coefficient of linear parallel ppm/K 43.6 39.0 43.3 38.4 40.1 34.8 34.5 35.4 30.3 56.2 53.0 thermal expansion trans- ppm/K 59.6 54.2 54.8 53.7 53.8 51.5 50.5 50.0 51.3 61.5 62.1 (CLTE) to verse DIN 53752 V = comparison

[0286] It is apparent from the examples of Tables 1 and 2 that the inventive examples, with comparable or better heat distortion resistance, have improved dimensional stability (CLTE), good impact resistance and better surface quality than the comparative examples (Examples 1, 2 and 3 versus V1 and V2). Moreover, a distinct improvement in thermal conductivity was surprisingly found for Examples 1, 2 and 3 over V1. If too low a content of component B is chosen, dimensional stability is inadequate (V1); too high a content of component B has an adverse effect on surface quality and impact resistance (V2). If some of component B is replaced by optional component D1 (boron nitride), heat distortion resistance, dimensional stability (CLTE), impact resistance and surface quality can be optimized, but the amount of D1 chosen must not be too high since surface quality is otherwise adversely affected (Examples 4, 5 and 6 versus V3). The improved properties of Example 2 can even be retained when a pigment E is additionally added (Example 7), but important properties such as surface quality and impact resistance are lost when the non-inventive component B3 is used in place of B2 (7 versus V4).

[0287] If a portion of component B is replaced by optional component D2 or D3 (expanded graphite), dimensional stability (CLTE) and thermal conductivity can be improved even further (examples 8 and 9), but a good surface quality results only when the inventive graphite D3 is used. When the non-inventive graphite D2 is used, surface quality is poor irrespective of the concentration of D2. Moreover, the inventive graphite D3 shows advantages in impact resistance and dimensional stability over D2 (Example 9 versus V5, 10 versus V6).

[0288] As shown by Examples 11 and 12, the improvement in the dimensional stability of Example 10 can be brought about with simultaneously high or improved heat distortion resistance in other polycarbonates (PC1) and copolycarbonates (PC2) as well. Here, in particular, the use of PC1 in Example 11 shows a surprisingly significant improvement in thermal conductivity that would not have been expected by the person skilled in the art.

[0289] As shown by Comparative Examples V7, V8, V9 and V10, the concentration of inventive component D3 chosen must not be too high since the result is otherwise a poor surface quality as is generally the case when the non-inventive component D2 is used.

[0290] All inventive examples, in spite of the high filler content, have good impact resistance to ISO179/1eU and good processibility in injection moulding processes, which is apparent from the melt viscosity profiles.