COMPOSITION AND METHOD FOR THE PRODUCTION OF A TRANSLUCENT THERMOPLASTIC POLYCARBONATE / POLYMETHYLMETHACRYLATE MOLDING COMPOSE

Description

[0001] The present invention relates to a polycarbonate / polymethyl methacrylate composition for producing a thermoplastic polycarbonate / polymethyl methacrylate molding compound, a process for producing the molding compound, the molding compound itself, the use of the molding compound for producing molded articles, the molded articles containing such a molding compound, and a process for producing molded articles.

[0002] Not least driven by the development of LED light source technology and the resulting new lighting and functional integration concepts, transparent and translucent thermoplastic molding compounds, which are suitable for the production of molded bodies that can be illuminated by visible light, have become increasingly important in many application areas in recent years, for example in the automotive sector, the construction sector and the electronics sector.

[0003] The property profile of traditional transparent thermoplastic polymer materials such as polycarbonate (PC) and polymethyl methacrylate (PMMA) is increasingly encountering technical limitations in many of these new applications. For example, translucent components in automotive interiors, such as instrument panel supports or decorative panels, or in automotive bodywork applications intended for ambient lighting or on-demand function displays, often require improved material ductility compared to PMMA, as well as improved scratch resistance or sunscreen resistance compared to PC. For the expert, it is therefore logical to use polymer blend technology to combine the individual advantages of these two materials (high scratch resistance and good sunscreen resistance of PMMA on the one hand, and high ductility of PC on the other).

[0004] The properties of such PC / PMMA blend molding compounds and the resulting molded articles can be varied widely and adapted to the requirements of the respective application by appropriately selecting their composition and manufacturing conditions. This allows molding compounds with a wide range of property profiles to be realized, which often lie essentially between those of pure PC and those of pure PMMA.

[0005] However, this fundamentally does not apply to transparency. Since PC and PMMA melts are not completely miscible, compounding PC / PMMA blends typically results in two-phase morphologies. The excess polymer forms the matrix phase, within which the other polymer is relatively finely dispersed, thus forming a multitude of microscopic interfaces. At these PC-PMMA interfaces, incident light is scattered due to the different refractive indices of the two polymers.

[0006] The result is a high opacity (i.e. very low light transmission) of the PC / PMMA blends compared to the two polymeric blend partners.

[0007] Furthermore, the phase boundaries can represent weak points with regard to mechanical stresses. These phase boundaries can lead to failure under external stresses acting on the molded body, especially when the molded body comes into contact with certain media such as fats or oils, which are components of food, lubricants, or cosmetic products (such as hand or sunscreen).

[0008] A previously inadequately addressed goal in materials development has been to provide PC / PMMA blends suitable for the production of transparent or translucent (i.e., translucent) molded articles using a thermoplastic forming process, and which offer an advantageous combination of the aforementioned properties compared to polycarbonate and polymethyl methacrylate. This would enable a wide range of technical challenges to be addressed.

[0009] In various scientific publications and patent documents of the last 10 years, it has been revealed that transparent PC / PMMA blends with improved technical properties can be produced by using block copolymers, which can often be formed in-situ in a reactive extrusion process.

[0010] WO 2020 / 212229 A1 discloses a reactive compounding process for producing a thermoplastic molding compound using aromatic polycarbonate and another polymer containing at least one type of functional group selected from ester, epoxy, hydroxy, carboxy, and carboxylic anhydride groups, with a specific phosphonium salt being used as the catalyst. The application also discloses, in particular, the production of transparent thermoplastic PC / PMMA molding compounds using such a process.

[0011] WO 2016 / 138246 A1 discloses transparent PC / PMMA blends containing 9.9 - 40 wt.% polycarbonate and 59.9 - 90 wt.% PMMA, which are produced by melt extrusion using 0.0025 - 0.1 wt.% of a tin catalyst.

[0012] US 2017 / 114218 A1 discloses a composition containing polycarbonate, polyethylene terephthalate, glycidyl methacrylate-ethylene-methylacrylate copolymer, vinyl acetate-ethylene copolymer, organic phosphorus-containing flame retardant and an anti-drip agent.

[0013] WO 2016 / 189494 A1 discloses transparent PC / PMMA blends containing 80-95 wt.% of a specifically specified branched polycarbonate with an end-cap content of 45%-80% and 4.9-20 wt.% PMMA, which are produced in a melt extrusion by transesterification using 0.1-1.5 wt.% of a catalyst, preferably selected from Zn, Sn and Ag compounds.

[0014] AK Singh, et al. "Reactive Compatibilization of Polycarbonate and Poly(methyl)methacrylate in the Presence of a Novel Transesterification Catalyst SnCl2·2H2O", J. Phys. Chem. B 2011, 115, 1601-1607 discloses transparent PC / PMMA molding compounds prepared in a reactive extrusion process using SnCl2·2H2O as a catalyst.

[0015] AK Singh, et al. "Evidence for in situ graft copolymer formation and compatibilization of PC and PMMA during reactive extrusion processing in the presence of the novel organometallic transesterification catalyst tin(II) 2-ethylhexanoate", RSC Advances, 2012, 2, 10316-10323 discloses translucent PC / PMMA molding compounds prepared in a reactive extrusion process using tin(II) 2-ethylhexanoate as a catalyst.

[0016] T. Bubmann et al., "Transparent PC / PMMA Blends Via Reactive Compatibilization in a Twin-Screw Extruder," Polymers 2019, 11, 2070, discloses that such PC+PMMA molding compounds produced in reactive extrusion processes according to the previously cited prior art are transparent due to an interpolymer transesterification reaction and thus the formation of PC-g-PMMA graft polymers during reactive extrusion, but exhibit insufficient material ductility for any industrial application. The reason for this is the molecular weight reduction of the polycarbonate associated with the transesterification, which also contributes significantly to the development of transparency in the blends produced in this way, since the miscibility of PC and PMMA improves with decreasing PC molecular weight, resulting in single-phase morphologies in the reactive-extruded blends.

[0017] US 8,975,346 B2 discloses a process for producing a block copolymer in which an aromatic PC with terminal OH groups and a weight-average molecular weight of at least 3400 g / mol is esterified with an acid halide to form a macroinitiator, and the resulting polycarbonate macroinitiator is reacted with a vinyl monomer, in particular methyl methacrylate, in a controlled radical atom transfer polymerization reaction. The PC-b-PMMA block copolymers thus produced are characterized by transparency and good scratch resistance.

[0018] EA Kang, et al., "The effects of PC-PMMA-block copolymer on the compatibility and interfacial properties of PC / SAN blends," Polymer Engineering and Science, 2000, 40 (11), 2374-2384, discloses PC-b-PMMA and PC-b-SAN block copolymers prepared by free radical polymerization of methyl methacrylate and a styrene / acrylonitrile mixture, respectively, in the presence of a vinyl-terminated PC in chloroform as solvent.

[0019] H. Jang et al., "Polycarbonate-co-PMMA block copolymers via atom transfer radical polymerization reaction," J. Nanosci. Nanotechnol., 2017, 17 (10), 7281-7386, discloses PC-b-PMMA block copolymers prepared by radical polymerization of methyl methacrylate in the presence of an allyl-terminated PC in tetrahydrofuran as a solvent. The block copolymers exhibit improved scratch resistance compared to PC.

[0020] The processes disclosed in the last three prior art documents, which utilize the grafting of PMMA onto specifically reactively modified polycarbonate macromonomers in (controlled) radical polymerization processes, are technologically complex, inefficient, expensive and difficult to implement industrially.

[0021] It was therefore desirable to provide a composition for producing a thermoplastic PC / PMMA molding compound, wherein the molding compound can be produced using a commercially available and industrially established compounding unit such as a single-screw extruder, co-rotating or counter-rotating twin-screw extruder, planetary roller extruder, internal kneader, or co-kneader, and wherein the molding compound can be used to produce translucent (translucent or transparent) molded articles with at least one mechanical property improved compared to such prior-art PC / PMMA molding compounds. Mechanical properties that were sought to be improved within the scope of the invention include, in particular, tensile strength, flexural strength, flexural elongation at break, scratch resistance, and chemical resistance.

[0022] In the context of the present application, a translucent shaped body is understood to mean a shaped body which has a local total light transmittance measured according to ISO 13468-1 (version of 2019) of at least 35%, preferably at least 50%, at least at one point.

[0023] It was also desirable to provide compositions for producing PC / PMMA molding compounds that are characterized by improved flexural strength compared to both pure PC and pure PMMA. In particular, a flexural strength of at least 100 MPa, measured according to ISO 178 (2019 version), is targeted.

[0024] Preferably, the molded articles produced should exhibit improved scratch resistance compared to pure polycarbonate and / or improved resistance to fats and oils and / or compositions containing fats and / or oils, such as cosmetics, hand creams, and sunscreen, compared to pure polycarbonate and / or prior-art PC / PMMA compositions. In particular, a scratch resistance of at least 2H, measured as a pencil hardness based on the Wolff-Wilborn method, is desired. Furthermore, an improvement in resistance to sunscreen compared to pure polycarbonate is particularly desired.

[0025] It was particularly desirable to provide compositions for producing PC / PMMA molding compounds which are suitable for producing translucent molded articles having a flexural strength measured according to ISO 178 (version of 2019) of at least 100 MPa, a scratch resistance measured as pencil hardness based on the Wolff-Wilborn method of at least 2H, preferably at least 3H, and an improved resistance to sunscreen compared to pure polycarbonate, wherein a molded article with a thickness of 1 mm produced from such a molding compound has a total light transmittance measured according to ISO 13468-1 (version of 2019) of at least 35%, preferably at least 50%.

[0026] Surprisingly, it has now been found that a composition for producing a thermoplastic molding compound containing A) at least one aromatic polycarbonate and / or aromatic polyestercarbonate containing at least 500 ppm by weight, preferably at least 1000 ppm by weight, particularly preferably at least 1500 ppm by weight, most preferably at least 1800 ppm by weight of phenolic OH groups, wherein the weight-average molecular weight M w , determined by gel permeation chromatography at room temperature in dichloromethane as solvent using a BPA polycarbonate calibration standard, of component A is in the range from 15,000 to 40,000 g / mol, preferably from 18,000 to 35,000 g / mol, particularly preferably from 19,000 to 30,000 g / mol, most preferably from 20,000 to 28,000 g / mol, B) at least one copolymer containing structural units derived from methyl methacrylate and 0.3 to 15% by weight, preferably 0.5 to 10 wt.%, particularly preferably 0.8 to 9 wt.%, most preferably 1 to 8 wt.-% based on component B, structural units derived from glycidyl methacrylate (GMA), wherein component B has a weight-average molecular weight M w , determined by means of gel permeation chromatography at room temperature in tetrahydrofuran as solvent using a polystyrene standard, of 20,000 to 200,000 g / mol, preferably of 30,000 to 150,000 g / mol, particularly preferably of 30,000 to 100,000 g / mol, most preferably of 50,000 to 80,000 g / mol, wherein in component B the ratio of M w in kg / mol to the weight fraction of structural units derived from glycidyl methacrylate in wt.% is in the range from 2 to 100, preferably in the range from 5 to 80, particularly preferably in the range from 5 to 50, most preferably in the range from 8 to 30. wherein the weight ratio of components A and B is in the range of 30:70 to 90:10, preferably in the range of 45:55 to 85:15, more preferably in the range of 60:40 to 85:15, has the desired properties.

[0027] Where wt. ppm means a weight percentage in parts per million.

[0028] In a preferred embodiment, the composition consists of 30 to 90% by weight, preferably 45 to 85% by weight, particularly preferably 58 to 82% by weight of component A, 10 to 70% by weight, preferably 14 to 54% by weight, particularly preferably 17 to 41% by weight of component B, 0 to 20% by weight, preferably 0.01 to 5% by weight, particularly preferably 0.02 to 1% by weight as component C polymer additives, process aids and / or polymers different from components A and B, wherein the % by weight of components A to C are selected so that they add up to 100% by weight.

[0029] In a further preferred embodiment, the product of the phenolic OH amount in ppm by weight introduced into the composition via component A and the amount of structural units derived from glycidyl methacrylate in % by weight introduced into the composition via component B is greater than 300. This product is calculated as the product of the amount of phenolic OH in component A (in ppm), the weight fraction of component A in the composition, the amount of structural units derived from glycidyl methacrylate in component B (in % by weight) and the weight fraction of component B in the composition.

[0030] In the case of compositions comprising a component B with a ratio of Mw in kg / mol to the weight fraction of structural units derived from glycidyl methacrylate in wt.% of >50 to 100, it is preferred to use a metal acetonate, preferably zirconium(IV) acetylacetonate, as component C or constituent of component C in order to achieve higher transmission. In the case of compositions comprising a component B with a ratio of Mw in kg / mol to the weight fraction of structural units derived from glycidyl methacrylate in wt.% of ≤ 50, on the other hand, such use of a metal acetonate is not necessary to achieve high transmission; in the case of compositions with a high PMMA content of >40 wt.%, it is even preferred not to use such a metal acetonate in order to achieve high transmission.If metal acetonate is used as component C or constituent of component C, it is preferably used in the compositions in an amount of 0.01 to 0.2 wt.%, particularly preferably 0.02 to 0.15 wt.%, most preferably in an amount of 0.03 to 0.1 wt.%. Component A

[0031] Component A consists of an aromatic polycarbonate and / or an aromatic polyestercarbonate. Mixtures of several aromatic polycarbonates and / or polyestercarbonates can also be used.

[0032] Aromatic polycarbonates according to component A which are suitable according to the invention are known from the literature or can be prepared by processes known from the literature (for the preparation of aromatic polycarbonates see, for example, Schnell, "Chemistry and Physics of Polycarbonates", Interscience Publishers, 1964 and DE-AS 1 495 626, DE-A 2 232 877, DE-A 2 703 376, DE-A 2 714 544, DE-A 3 000 610, DE-A 3 832 396).

[0033] Aromatic polycarbonates are produced, for example, by reacting diphenols with carbonic acid halides, preferably phosgene, and / or with aromatic dicarboxylic acid dihalides, preferably benzenedicarboxylic acid dihalides, by the interfacial process, optionally using chain terminators, for example monophenols, and optionally using trifunctional or more than trifunctional branching agents, for example triphenols or tetraphenols. Production via a melt polymerization process is also possible by reacting diphenols with, for example, diphenyl carbonate in the presence of a transesterification catalyst.

[0034] The melt polymerization process is particularly suitable for producing the polycarbonates according to component A of the invention. Therefore, aromatic polycarbonates produced by the melt polymerization process are preferably used as component A. The molecular weight and the proportion of phenolic OH end groups are adjusted in particular by the ratio of diphenols to diphenyl carbonate and the reaction regime (in particular temperature, residence times, vacuum, and catalyst type and amount). The molar ratio of diphenyl carbonate to diphenols is preferably set in the range 1.00 to 1.07, more preferably in the range 1.01 to 1.05, most preferably in the range 1.02 to 1.04.This ratio regulates the correlation between the molecular weights and the proportion of phenolic OH end groups, whereby the molecular weights (and thus also the proportion of phenolic OH end groups) can be adjusted within this correlation by the residence times for the selected reaction regime (such as temperature, vacuum, as well as catalyst type and amount).

[0035] When producing polycarbonates according to component A in the interfacial process, a molar excess of diphenols relative to carbonyl chloride is used. The target molecular weight is adjusted by the ratio of diphenols to carbonyl halide. The content of phenolic OH end groups can be controlled in this case by the molar ratio of monophenolic chain terminator to diphenol. In a special embodiment, no monophenolic chain terminator is used in the production of polycarbonates according to component A in the interfacial process. This results in a polycarbonate with a 100% proportion of phenolic OH groups at the end groups in the polycarbonate.

[0036] Diphenols for the preparation of the aromatic polycarbonates and / or aromatic polyester carbonates are preferably those of the formula (1) where A is a single bond, C 1 to C 5 alkylene, C 2 to C 5 alkylidene, C 5 to C 6 cycloalkylidene, -O-, -SO-, -CO-, -S-, -SOz-, C 6 to C 12 arylene, to which further aromatic rings optionally containing heteroatoms may be condensed, or a radical of the formula (2) or (3) B is each C 1 to C 12 alkyl, preferably methyl, halogen, preferably chlorine and / or bromine, x is each independently 0, 1 or 2, p is 1 or 0, and R 5< and R 6< can be selected individually for each X 1<, independently of one another are hydrogen or C 1 to C 6 alkyl, preferably hydrogen, methyl or ethyl, X 1 is carbon and m is an integer from 4 to 7, preferably 4 or 5, with the proviso that on at least one atom X 1<, R 5< and R 6< are simultaneously alkyl.

[0037] Preferred diphenols are hydroquinone, resorcinol, dihydroxydiphenols, bis-(hydroxyphenyl)-C 1 -C 5 -alkanes, bis-(hydroxyphenyl)-C 5 -C 6 -cycloalkanes, bis-(hydroxyphenyl) ethers, bis-(hydroxyphenyl) sulfoxides, bis-(hydroxyphenyl) ketones, bis-(hydroxyphenyl) sulfones and α,α,-bis-(hydroxyphenyl)-diisopropylbenzenes and their nuclear-brominated and / or nuclear-chlorinated derivatives.

[0038] Particularly preferred diphenols are 4,4'-dihydroxydiphenyl, bisphenol A, 2,4-bis(4-hydroxyphenyl)-2-methylbutane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 4,4'-dihydroxydiphenyl sulfide, 4,4'-dihydroxydiphenyl sulfone, and their di- and tetrabrominated or chlorinated derivatives, such as 2,2-bis(3-chloro-4-hydroxyphenyl)propane, 2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane, or 2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane. 2,2-bis(4-hydroxyphenyl)propane (bisphenol A) is particularly preferred.

[0039] The diphenols can be used individually or as any mixture. The diphenols are known from the literature or are available by known methods.

[0040] In a preferred embodiment, the proportion of bisphenol A, based on the sum of all diphenols used to produce component A, is at least 50 mol%, particularly preferably at least 75 mol%, and most preferably at least 95 mol%. Most preferably, bisphenol A is used exclusively as the diphenol in the production of component A.

[0041] The aromatic polycarbonates contain at least 500 ppm by weight, preferably at least 1000 ppm by weight, particularly preferably at least 1500 ppm by weight, and most preferably at least 1800 ppm by weight of phenolic OH groups. These phenolic OH groups are end groups. The aromatic polycarbonates according to component A, if they are linear polycarbonates, are generally mixtures of polycarbonate molecules with one, two, or no phenolic OH groups. Branched polycarbonates may also contain polycarbonate molecules with more than two phenolic OH groups. In a preferred embodiment, 25 to 100 mol%, particularly preferably 30 to 80 mol%, and most preferably 40 to 75 mol% of the end groups in the polymer molecules of component A are present as phenolic OH groups.The proportion of phenolic OH groups at the end groups in linear polycarbonates can be determined using a rule of three from the number-average molecular weight of the polycarbonate M n (in g / mol) and its content of phenolic OH groups (in ppm by weight), whereby a content of phenolic OH groups (in ppm by weight) of (34 g / mol)- 10 6< / M n corresponds to a proportion of phenolic OH groups of 100%.

[0042] More preferably, the aromatic polycarbonates contain 500 ppm by weight to 3000 ppm by weight, particularly preferably 1500 ppm by weight to 3000 ppm by weight and most preferably 1800 to 2800 ppm by weight of phenolic OH groups.

[0043] The content of phenolic OH groups is determined by 1< H NMR spectroscopy with dichloromethane as solvent at room temperature by evaluating the ratio of the integrals of the signals at 6.68 ppm (2 aromatic protons ortho to phenolic OH groups) and at 1.68 ppm (6 methyl protons of the bisphenol A unit).

[0044] Unless expressly stated otherwise, all ppm amounts in the present invention are to be understood as parts by weight.

[0045] Chain terminators suitable for the production of aromatic polycarbonates in the interfacial process are, for example, phenol, p-chlorophenol, p-tert-butylphenol or 2,4,6-tribromophenol, but also long-chain alkylphenols, such as 4-[2-(2,4,4-trimethylpentyl)]-phenol, 4-(1,3-tetramethylbutyl)-phenol according to DE-A 2 842 005 or monoalkylphenol or dialkylphenols with a total of 8 to 20 carbon atoms in the alkyl substituents, such as 3,5-di-tert-butylphenol, p-isooctylphenol, p-tert-octylphenol, p-dodecylphenol and 2-(3,5-dimethylheptyl)-phenol and 4-(3,5-dimethylheptyl)-phenol.

[0046] The aromatic polycarbonates have weight-average molecular weights M w , measured by GPC (gel permeation chromatography) at room temperature in methylene chloride with BPA polycarbonate standard), of 15,000 to 40,000 g / mol, preferably of 18,000 to 35,000 g / mol, particularly preferably of 19,000 to 30,000 g / mol and most preferably of 20,000 to 28,000 g / mol.

[0047] The aromatic polycarbonates may be branched in a known manner, preferably by incorporating 0.01 to 2.0 mol%, based on the sum of the diphenols used, of trifunctional or more than trifunctional compounds, for example those with three or more phenolic groups.

[0048] Preference is given to using linear aromatic polycarbonates, more preferably linear aromatic polycarbonates based on bisphenol A, particularly preferably based exclusively on bisphenol A.

[0049] Aromatic dicarboxylic acid dihalides for the production of aromatic polyester carbonates are preferably the diacid dichlorides of isophthalic acid, terephthalic acid, diphenyl ether-4,4'-dicarboxylic acid and naphthalene-2,6-dicarboxylic acid.

[0050] Particularly preferred are mixtures of the diacid dichlorides of isophthalic acid and terephthalic acid in a ratio between 1:20 and 20:1.

[0051] In the production of polyester carbonates, a carbonic acid halide, preferably phosgene, is also used as a bifunctional acid derivative.

[0052] In addition to the monophenols already mentioned, suitable chain terminators for the production of aromatic polyester carbonates are their chlorocarbonic acid esters and the acid chlorides of aromatic monocarboxylic acids, which may optionally be substituted by C1 to C22 alkyl groups or by halogen atoms, as well as aliphatic C2 to C22 monocarboxylic acid chlorides.

[0053] In the production of aromatic polyester carbonates, one or more aromatic hydroxycarboxylic acids can additionally be used.

[0054] The aromatic polyester carbonates can be either linear or branched in a known manner (see DE-A 2 940 024 and DE-A 3 007 934), with linear polyester carbonates being preferred.

[0055] Branching agents which can be used include, for example, trifunctional or polyfunctional carboxylic acid chlorides, such as trimesic acid trichloride, cyanuric acid trichloride, 3,3'-,4,4'-benzophenonetetracarboxylic acid tetrachloride, 1,4,5,8-naphthalenetetracarboxylic acid tetrachloride or pyromellitic acid tetrachloride, in amounts of 0.01 to 2.0 mol% based on the dicarboxylic acid dichlorides used, or trifunctional or polyfunctional phenols, such as phloroglucinol, 4,6-dimethyl-2,4,6-tri-(4-hydroxyphenyl)-hept-2-ene, 4,6-dimethyl-2,4-6-tri-(4-hydroxyphenyl)-heptane, 1,3,5-tri-(4-hydroxyphenyl)-benzene, 1,1,1-tri-(4-hydroxyphenyl)-ethane, tri-(4-hydroxyphenyl)-phenylmethane, 2,2-bis[4,4-bis(4-hydroxyphenyl)cyclohexyl]propane, 2,4-bis(4-hydroxyphenylisopropyl)phenol, tetra(4-hydroxyphenyl)methane, 2,6-bis(2-hydroxy-5-methylbenzyl)-4-methylphenol, 2-(4-Hydroxyphenyl)-2-(2,4-dihy-droxyphenyl)-propane, tetra-(4-[4-hydroxyphenyl-isopropyl]-phenoxy)-methane, 1,4-bis[4,4'-dihydroxytri-phenyl)-methyl]-benzene, in amounts of 0.01 to 2,0 mol% based on the diphenols used. Phenolic branching agents can be added with the diphenols; acid chloride branching agents can be added together with the acid dichlorides.

[0056] The proportion of carbonate structural units in the thermoplastic aromatic polyester carbonates can vary as desired. The proportion of carbonate groups is preferably up to 100 mol%, in particular up to 80 mol%, and particularly preferably up to 50 mol%, based on the sum of ester groups and carbonate groups. Both the ester and carbonate portions of the aromatic polyester carbonates can be present in the form of blocks or randomly distributed in the polycondensate.

[0057] Most preferably, linear aromatic polycarbonates based on bisphenol A are used exclusively as component A, particularly preferably exclusively based on bisphenol A. Component B

[0058] Component B is a copolymer containing structural units derived from methyl methacrylate and 0.3 to 15 wt.%, preferably 0.5 to 10 wt.%, particularly preferably 0.8 to 9 wt.%, and most preferably 1 to 8 wt.% of structural units derived from glycidyl methacrylate (GMA). Mixtures of such copolymers can also be used.

[0059] The term "copolymer containing structural units derived from" means that the copolymer is prepared from the said monomers by copolymerization.

[0060] Component B has a weight-average molecular weight M w determined by gel permeation chromatography at room temperature in tetrahydrofuran as solvent with a polystyrene standard of 20,000 to 200,000 g / mol, preferably of 30,000 to 150,000 g / mol, particularly preferably of 30,000 to 100,000 g / mol, most preferably of 50,000 to 80,000 g / mol.

[0061] In component B, the ratio of M w in kg / mol to the weight fraction of structural units derived from glycidyl methacrylate in wt. % is in the range from 2 to 100, preferably in the range from 5 to 80, particularly preferably in the range from 5 to 50 and most preferably in the range from 8 to 30.

[0062] The copolymers according to component B can contain up to 50 wt. %, preferably up to 25 wt. %, particularly preferably up to 10 wt. %, of structural units derived from further copolymerizable vinylic, preferably acrylic (i.e., containing acrylic groups) monomers. Examples of suitable copolymerizable acrylic monomers include methyl acrylate, ethyl acrylate, propyl acrylate, butyl acrylate, hexyl acrylate, 2-ethylhexyl acrylate, butyl methacrylate, and other compounds structurally related to these acrylates.

[0063] In a most preferred embodiment, component B does not contain any structural units derived from other copolymerizable monomers.

[0064] The copolymers according to component B are thermoplastic.

[0065] The preparation of the copolymers according to component B containing structural units derived from methyl methacrylate and glycidyl methacrylate is known to the person skilled in the art and is preferably carried out by radically initiated polymerization of the corresponding monomers, in particular by emulsion, suspension, solution or bulk polymerization.

[0066] In solution polymerization, which is preferably carried out in aprotic solvents, for example optionally halogen-substituted aliphatic or aromatic hydrocarbons as solvents, conditions that at least largely prevent hydrolysis of the epoxy groups are preferably maintained. Suitable and preferred conditions for this include, for example, low contents of protic solvents such as water, alcohols, acids, or bases and working in solvents from the group of organic hydrocarbons that are inert toward epoxy groups, such as toluene, ethylbenzene, xylene, high-boiling aliphatics, chlorinated aromatic hydrocarbons such as mono-, di-, tri-, or tetrachlorobenzenes, chlorinated aliphatic hydrocarbons such as dichloromethane or chloroform, ketones such as methyl ethyl ketone, esters, or ethers.

[0067] By adding regulators, especially sulfur regulators, especially mercaptans, the molecular weights of component B can be adjusted during the radical polymerization so that the weight-average molecular weight M w according to the invention results. Component C

[0068] As component C, one or more polymer additives, processing aids and / or further polymeric components different from A and B can be included in the composition, preferably selected from the group consisting of flame retardants, anti-drip agents, flame retardant synergists, smoke inhibitors, lubricants and mold release agents, nucleating agents, polymeric and non-polymeric antistatic agents, conductivity additives, stabilizers (e.g. hydrolysis, heat aging and UV stabilizers as well as transesterification inhibitors), flow promoters, phase compatibilizers, impact modifiers (both with and without core-shell structure), polymeric blend partners, catalysts, fillers and reinforcing materials as well as dyes and pigments.

[0069] The selection and amount of component C is such that the influences on mechanical properties and transparency of the molded articles produced from the molding compositions are as small as possible, i.e. such that the addition of component C does not conflict with the solution of the problem according to the invention.

[0070] If component C is used, it is used in a maximum proportion of 20 wt.%, based on the composition. This proportion is then the sum of all polymer additives, processing aids, and polymer components used as component C.

[0071] Anti-drip agents, flame retardant synergists, smoke inhibitors, lubricants and mold release agents, nucleating agents, non-polymeric antistatic agents, conductivity additives and stabilizers are preferably used in a proportion of 0.1 to 1 wt.% each and in total preferably in a proportion of 0.1 to 3 wt.%, based on the composition.

[0072] If flame retardants are used, they are preferably used in an amount of 1 to 15% by weight, based on the composition.

[0073] If flow promoters, polymeric antistatic agents and phase compatibilizers are used, the proportion used is preferably 1 to 10 wt.% in each case and in total preferably 1 to 15 wt.%, based on the composition.

[0074] If impact modifiers or polymeric blend parts are used, the total amount used is preferably 1 to 18 wt.%, based on the composition.

[0075] If dyes or pigments are used, the proportion used is preferably 0.1 to 10% by weight, based on the composition.

[0076] In a preferred embodiment, inorganic pigments are used in a total amount of not more than 3 wt.%, particularly preferably not more than 1.5 wt.%, and further preferably not more than 0.5 wt.%, based in each case on the composition. In the most preferred embodiment, no inorganic pigments are used as a constituent of component C.

[0077] If fillers and reinforcing materials are used, the proportion used is preferably 3 to 10 wt.%, based on the composition.

[0078] In a preferred embodiment, no fillers or reinforcing materials are used.

[0079] In a preferred embodiment, at least one polymer additive selected from the group consisting of lubricants and mold release agents, stabilizers, flow promoters, phase compatibilizers, impact modifiers, other polymeric blend partners and dyes is used.

[0080] In a preferred embodiment, pentaerythritol tetrastearate is used as a mold release agent.

[0081] In a preferred embodiment, at least one member selected from the group consisting of sterically hindered phenols, organic phosphites and sulfur-based co-stabilizers is used as the stabilizer.

[0082] In a particularly preferred embodiment, at least one representative selected from the group consisting of octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and tris(2,4-di-tert-butylphenyl)phosphite is used as stabilizer.

[0083] In a particularly preferred embodiment, a metal acetylacetonate is used as a constituent of component C. Examples of suitable metal acetylacetonates are aluminum(III) acetylacetonate, Ni(II) acetylacetonate, Fe(III) acetylacetonate, Zn acetylacetonate, Zr(IV) acetylacetonate, La(III) acetylacetonate, and Sa(III) acetylacetonate. Mixtures of several metal acetylacetonates can also be used. Zirconium(IV) acetylacetonate is particularly preferably used as the metal acetylacetonate. The metal acetylacetonates are preferably used in a total amount of 0.01 to 0.2 wt. %, more preferably in a total amount of 0.02 to 0.15 wt. %, most preferably in a total amount of 0.03 to 0.1 wt. %, based in each case on the composition. Production of molding compositions and moldings from the compositions according to the invention

[0084] Thermoplastic molding compositions can be produced from the compositions according to the invention.

[0085] The thermoplastic molding compositions according to the invention can be prepared, for example, by mixing the respective components of the compositions together at temperatures of 200°C to 320°C, preferably at 240 to 300°C, particularly preferably at 250 to 270°C.

[0086] The invention also relates to a corresponding process for producing the molding compositions according to the invention.

[0087] The procedure includes the steps (i) melting the components of the composition by introducing thermal energy and / or mechanical shear, (ii) mixing and dispersing the various components of the composition with or into each other, (iii) solidifying the melt by cooling, (iv) granulating the solidified polymer blend resulting from steps (i) - (iii).

[0088] The residence time of the components at the above-mentioned temperatures is preferably in the range of 15 seconds to 30 minutes, more preferably 30 seconds to 20 minutes. When using extruders or continuous co-kneaders as the compounding unit, the residence time is preferably 15 seconds to 5 minutes, particularly preferably 30 seconds to 2 minutes.

[0089] After step ii), the present composition can also be degassed by applying a negative pressure. The absolute pressure is preferably set to a maximum of 400 mbar, more preferably to a maximum of 200 mbar, and most preferably to a maximum of 100 mbar.

[0090] Mixing can take place in conventional equipment, such as single-screw extruders, co-rotating or counter-rotating twin-screw extruders, planetary roller extruders, internal kneaders, or continuous or discontinuous co-kneaders. In these, the compositions are melt compounded or melt extruded to form molding compounds. This process is generally referred to as compounding in the context of this application. Molding compound is therefore understood to be the product obtained when the components of the composition are melt compounded and melt extruded. Such a molding compound is a further subject matter of the present invention.

[0091] The mixing of the individual components of the compositions can be carried out in a known manner both successively and simultaneously, both at approximately 20°C (room temperature) and at higher temperatures. This means that, for example, some of the components can be metered via the main feed of an extruder, and the remaining components can be added later in the compounding process via a side extruder.

[0092] When carrying out the process described above, in a preferred embodiment, the epoxy groups in the structural units derived from glycidyl methacrylate in component B are partially or completely reacted in a chemical reaction. The reaction can be detected by determining the epoxy content measured according to ASTM D1652-11 (2011 version) in dichloromethane as the solvent.

[0093] When carrying out the process described above, component A or a portion of component A is preferably chemically coupled to component B or a portion of component B to form a PC-PMMA copolymer. Generally, the copolymer resulting from the reaction of polymers A and B is a block copolymer or graft copolymer.

[0094] It is further preferred that the mixture used in step i) containing components A, B, and optionally C has a residual moisture content determined by Karl Fischer titration of 0.01 to 0.50 wt.%, more preferably 0.07 to 0.20 wt.%, based in each case on the sum of A, B, and C. Excessively high moisture content poses a risk of undesirably high molecular weight degradation.

[0095] The molding compounds of the invention can be used to produce molded articles of any type. These can be produced, for example, by injection molding, extrusion, and blow molding. Another processing method is the production of molded articles by deep drawing from previously produced sheets or films. The molding compounds of the invention are particularly suitable for processing by extrusion, blow molding, and deep drawing processes.

[0096] It is also possible to dose the components of the compositions directly into the conveyor extruder of an injection molding machine, to produce the molding compound according to the invention in the conveyor extruder and to process it directly into molded articles by appropriately discharging the molding compound into an injection mold (compounding or reactive compounding injection molding).

[0097] Such a method is a further subject of the present invention and comprises the following steps: (i) Dosing the components of the composition according to the invention into the conveyor extruder of an injection molding machine, (ii) Melting the components of the composition according to the invention by introducing thermal energy and / or mechanical shear, (iii) Conveying the melt to the discharge point of the extruder, (iv) Discharge of the melt from the conveyor extruder into an injection mold, (v) Cooling and solidifying the melt in the injection mold to form a molded body, (vi) Removing the molded body from the injection mold.

[0098] In a preferred embodiment of this process, the residence time of the melt in the conveying extruder is at least two, more preferably at least five, particularly preferably at least ten minutes.

[0099] In a preferred embodiment of this process, the residence time of the melt in the conveying extruder is 2 to 30 minutes, more preferably 5 to 20 minutes, particularly preferably 7 to 15 minutes.

[0100] In a preferred embodiment, process steps (iii) and (iv) are carried out under shearing. This can be achieved, for example, by a high screw speed during melt conveyance in step (iii) and / or by a suitable screw configuration of the conveying screw, for example, by the use of kneading elements, as well as by a suitably narrow geometry of the melt outlet nozzle in step (iv).

[0101] A further subject matter of the present invention thus relates to the use of a composition according to the invention or a molding composition according to the invention for producing molded articles, and also to a molded article which is obtainable from a composition according to the invention or from a molding composition according to the invention or which contains such a molding composition.

[0102] Examples of such molded articles are films, profiles, housing parts of all kinds, e.g. for household appliances such as juicers, coffee machines, mixers; for office machines such as monitors, flat screens, notebooks, printers, copiers; panels, pipes, electrical installation ducts, windows, doors and other profiles for the construction sector (interior and exterior applications) as well as electrical and electronic parts such as switches, plugs and sockets and components for commercial vehicles, particularly for the automotive sector.The compositions and molding compounds according to the invention are also suitable for producing the following molded bodies or molded parts: interior fittings for rail vehicles, ships, aircraft, buses and other motor vehicles, body parts for motor vehicles, housings of electrical devices containing small transformers, housings for information processing and transmission devices, housings and cladding of medical devices, massage devices and housings therefor, toy vehicles for children, flat wall elements, housings for safety devices, heat-insulated transport containers, molded parts for sanitary and bathroom equipment, cover grilles for ventilation openings and housings for gardening tools.

[0103] Due to their particular technical properties, the compositions and molding compounds according to the invention are particularly suitable for the production of molded articles transilluminable with light in the visible wavelength range, for example, an LED light source, for lighting applications in the automotive sector, the construction sector, and the electronics sector. They are particularly suitable for the production of transilluminable molded parts for use in automotive interiors, such as instrument panel supports or decorative panels, or in automotive body applications intended, for example, for ambient lighting or a need-based function display (for example, day / night differentiation). Examples Compositions Component A1

[0104] Bisphenol A-based polycarbonate, produced by the interfacial process, with a weight-average molecular weight Mw of 25,000 g / mol, measured at room temperature in methylene chloride as solvent using an FTIR detector at a wavenumber of 1775 cm -1 and against a BPA polycarbonate calibration standard. Component A1 contains <100 wt. ppm of phenolic OH groups, measured by 1< H NMR spectroscopy. Component A2

[0105] Bisphenol A-based polycarbonate, produced by melt polymerization, with a weight-average molecular weight Mw of 24,000 g / mol (Mn of 11,000 g / mol), measured at room temperature in methylene chloride as solvent using an FTIR detector at a wavenumber of 1775 cm -1 and against a BPA polycarbonate calibration standard. Component A2 contains 2200 ppm by weight of phenolic OH groups, measured by 1< H NMR spectroscopy. A molar ratio of diphenyl carbonate to bisphenol A of 1.02 was used in the preparation. Component A3

[0106] Bisphenol A-based polycarbonate, produced by the interfacial process, with a weight-average molecular weight Mw of 20,000 g / mol, measured at room temperature in methylene chloride as solvent using an FTIR detector at a wavenumber of 1775 cm -1 and against a BPA polycarbonate calibration standard. Component A3 contains <100 wt. ppm of phenolic OH groups, measured by 1< H NMR spectroscopy. Component A4

[0107] Bisphenol A-based polycarbonate, produced by melt polymerization, with a weight-average molecular weight Mw of 20,000 g / mol (Mn of 9,200 g / mol), measured at room temperature in methylene chloride as solvent using an FTIR detector at a wavenumber of 1,775 cm -1 and against a BPA polycarbonate calibration standard. Component A4 contains 2,700 ppm by weight of phenolic OH groups, measured by 1< H NMR spectroscopy. A molar ratio of diphenyl carbonate to bisphenol A of 1.02 was used in the preparation. Component B1

[0108] Polymethyl methacrylate with a weight-average molecular weight M w of 58000 g / mol, measured by gel permeation chromatography at room temperature in tetrahydrofuran as solvent with a refractive index detector and against a polystyrene calibration standard. Component B2

[0109] Polymethyl methacrylate-glycidyl methacrylate random copolymer with a content of glycidyl methacrylate-derived structural units of 1 wt% and with a weight-average molecular weight M w of 34000 g / mol, measured by gel permeation chromatography at room temperature in tetrahydrofuran as solvent with a refractive index detector and against a polystyrene calibration standard. Component B3

[0110] Polymethyl methacrylate-glycidyl methacrylate random copolymer with a content of glycidyl methacrylate-derived structural units of 1 wt.% and with a weight-average molecular weight M w of 60000 g / mol, measured by gel permeation chromatography at room temperature in tetrahydrofuran as solvent with a refractive index detector and against a polystyrene calibration standard. Component B4

[0111] Polymethyl methacrylate-glycidyl methacrylate random copolymer with a content of glycidyl methacrylate-derived structural units of 8 wt.% and with a weight-average molecular weight M w of 68000 g / mol, measured by gel permeation chromatography at room temperature in tetrahydrofuran as solvent with a refractive index detector and against a polystyrene calibration standard. Component C1

[0112] Catana ™< CAA 2950: Zirconium (IV) acetylacetonate catalyst (Sachem Inc., Austin, Texas, USA) Production of thermoplastic molding compounds

[0113] The raw materials used for the production of the thermoplastic molding compounds were dried under vacuum at 60 °C for at least 7 hours prior to compounding. Both polymer components A and B were used in compounding as powders, which were produced from granules by cryogenic grinding.

[0114] The thermoplastic molding compounds with the compositions shown in Table 1 were produced with a residence time of 15 min at a melt temperature of 260°C and a rotational speed of 100 min -1< on a discontinuous microcompounder of the type DSM-Xplore ®< MC15 (Xplore Instruments BV, Sittard, Netherlands) from previously prepared powder mixtures of components A, B, and optionally C. The batch size was 15 g, from which approximately 7 g of usable material was obtained for further characterization of the compounds.

[0115] The thermoplastic molding compounds with the compositions shown in Table 2 were compounded on a continuous twin-screw extruder of the Process 11 type (Thermofischer Scientific, Karlsruhe, Germany) with a dispersing screw configuration with three mixing zones at a melt temperature of 260°C, a throughput of approximately 300 g / h, a speed of 200 min-1 and a residence time of approximately 90 s. After exiting through a die plate, the melt strand was cooled, thereby solidifying and then granulated. For these compounds, too, powder mixtures of components A to C were first prepared and these were evenly metered into the inlet zone of the twin-screw extruder via a volumetric metering device. In order to achieve the most homogeneous distribution possible of the very small amounts of component C in these powder mixtures, component C was added as 2 wt.-% solution in ethanol is applied as evenly as possible to the powder mixture of components A and B, then the mixture thus prepared is tempered at 60°C in a circulating air oven and subsequently dried overnight by applying a vacuum at 60°C (i.e. the ethanol is removed again). Production of the test specimens

[0116] Round plates with a diameter of 18 mm and a thickness of 1 mm for the transmission measurements and non-standard mini flat bar test specimens measuring 30 mm x 6 mm x 1 mm for the 3-point bending tests were produced from the thermoplastic molding compounds, which were produced from the compositions according to Table 1, using a laboratory thermopress from P / O / Weber (Remshalden, Germany) at a temperature of 260°C, a pressure of 60 bar and a pressing time of 4 min in total.

[0117] Rectangular plates measuring 80 mm x 80 mm x 1 mm and test bars measuring 80 mm x 10 mm x 4 mm were produced from the thermoplastic molding compounds, which were produced from the compositions according to Table 2, on an injection molding machine of the type Arburg 470 H 1000-170 from Arburg GmbH + Co KG (Loßburg, Germany) at a melt temperature of 270°C, a mold temperature of 60°C and an injection pressure of 2000 bar. Under the same conditions, non-standard shoulder beam test specimens were manufactured for the tensile tests with the dimensions 1 3 =120 mm (total length), 1 2 =83 mm (distance between the wide parallel parts), 1 1 =70 mm (length of the narrow parallel part), h=3 mm (thickness), b 1 =8 mm (width of the narrow part) and b 2 =16 mm (width at the ends), whereby the designations of the dimensions of the test specimens have the same meaning as in DIN EN ISO 527-2 (version of 1996). Application-related tests

[0118] The tensile properties (tensile strength and Young's modulus) were determined in a tensile test based on ISO 527-1 (2019 version) using non-standard shoulder-beam test specimens at room temperature. "Based on ISO 527-1" means that non-standard shoulder-beam test specimens were used.

[0119] The determination of flexural strength, flexural modulus, elongation at break, and - in the case of tests on non-standard test specimens - the deflection length at fracture failure was carried out at room temperature in 3-point bending tests on test specimens measuring 30 mm x 6 mm x 1 mm (Table 1) and 80 mm x 10 mm x 4 mm (Table 2). The tests on the 80 mm x 10 mm x 4 mm test specimens (Table 2) were carried out in accordance with ISO 178 (2019 version). The 3-point bending tests on the non-standard test specimens measuring 30 mm x 6 mm x 1 mm (Table 1) were carried out using a GABO EPLEXOR ®< 500 N testing device from Netzsch-Gerätebau GmbH (Selb, Germany) at a test speed of 5 mm / min.

[0120] Pencil hardness was determined as a measure of scratch resistance. The measurement was carried out at room temperature using a TriForcePencil Model 293 scratch hardness tester from Erichsen GmbH & Co. KG (Hemer, Germany) according to the manufacturer's test specifications based on the Wolff-Wilborn method on test panels measuring 80 mm x 80 mm x 1 mm. The pencils were clamped into the measuring fixture at an angle of 45° to the test surface and pushed across the specimen surface with a test force of 5 N. The test started with the hardest pencil, and the hardness was then successively reduced. The pencil hardness of the pencil whose tip was the first to no longer leave a noticeable scratch during this procedure is considered the parameter characterizing the scratch resistance of the plastic surface.

[0121] Sunscreen resistance was assessed using the sunscreen test mixture test agent MB-PM001, which was purchased from Thierry Präzisionslackiertechnik GmbH (Stuttgart, Germany), on rectangular panels measuring 80 mm x 80 mm x 1 mm. The test specimens were first cleaned with deionized water and blown dry before a drop of sunscreen measuring approximately 7-10 mm in diameter was applied to the test specimens. The samples, which had been exposed to the sunscreen test mixture in this way, were then stored at 50 °C for 6 hours or 24 hours. After cooling to room temperature, the sunscreen was carefully removed from the test specimen with a cloth. The test specimens were then stored at room temperature for another 7 days before being tested for breakage and cloudiness in accordance with ISO 14782 (1999 version).One criterion for sunscreen resistance is whether cracking occurs on the test specimen during sunscreen exposure (worst behavior). For molding compounds that do not exhibit such cracking on the test specimen due to sunscreen exposure, the change in turbidity (i.e., the difference between the turbidity values ​​measured before and after sunscreen exposure) serves as a measure of sunscreen resistance, with a smaller change in turbidity corresponding to improved sunscreen resistance.

[0122] The transparency of the molding compounds was assessed on round plates with a diameter of 18 mm and a thickness of 1 mm (Table 1) or on rectangular plates measuring 80 mm x 80 mm x 1 mm (Table 2) at room temperature according to ISO 13468-1 (version of 2019) by determining the total light transmittance (hereinafter referred to synonymously as "transmission"). Table 1: Compositions and properties of the resulting molding compounds (molding compounds produced in the microcompounder, test specimens produced by thermopressing) composition R1 R2 R3 R4 R5 R6 V7 V8 V9 10 11 12 13 14 15 16 V17 V18 V19 A1 100 80 80 80 80 A2 100 80 50 80 80 80 80 80 50 50 B1 100 20 20 50 B2 100 20 20 B3 100 20 20 20 B4 100 20 20 50 50 20 C1 0,05 0,05 0,05 Feature of component B M w [kg / mol] - - 58 34 60 68 58 58 58 60 60 34 68 68 68 68 34 60 68 GMA structural units [wt.%] 0 1 1 8 0 0 0 1 1 1 8 8 8 8 1 1 8 M w [kg / mol] / GMA [wt%] - - ∞ 34 60 8,5 ∞ ∞ ∞ 60 60 34 8,5 8,5 8,5 8,5 34 60 8,5 Characteristics Flexural strength [MPa] 84 90 86 nm 34 50 96 100 88 104 107 106 111 128 110 122 ng ng ng Deflection length at break [mm] >5,5 >5,5 0,7 nm <0,3 <0,3 >5,5 >5,5 1,3 >5,5 >5,5 >5,5 >5,5 >5,5 >5,5 >5,5 ng ng ng Transmission [%] 19 27 21 36 70 64 60 52 56 39 17 17 18 nm = not measurable, because no test specimens could be produced in the thermopressing process due to excessive material brittleness or they broke during the demoulding attempt due to high material brittleness ng = not measured R = reference test, V = comparison test

[0123] Due to the measuring equipment, deflection lengths could only be measured up to a maximum of 5.5 mm. If no fracture was observed at this maximum measurable deflection length, the deflection length at fracture is specified as ">5.5 mm". Table 2: Compositions and properties of the resulting molding compounds (molding compounds produced in a twin-screw extruder, test specimens produced by injection molding) composition V20 21 22 23 R24 R25 A1 100 A3 80 A4 80 80 80 B1 20 100 B2 20 B4 20 20 C1 0,05 Feature of component B M w [kg / mol] 58 34 68 68 - 58 GMA structural units [wt.%] 0 1 8 8 - 0 M w [kg / mol] / GMA [wt%] ∞ 34 8,5 8,5 - ∞ Characteristics Flexural modulus [MPa] 2447 2567 2519 2559 Flexural strength [MPa] 98 104 101 101 Tensile modulus [MPa] 2586 2768 2717 2797 Tensile strength [MPa] 61 66 66 67 Transmission [%] 26 65 59 65 Pencil hardness 2H 2H 3H 3H F 4H Sunscreen test (cracking on test specimen) Yes no no no no Sunscreen test (turbidity change after 50°C / 6 h) [%] nm 20 ng ng 33 Sunscreen test (turbidity change after 50°C / 24 h) [%] nm 34 ng 29 47 nm = not measurable because the test specimen broke as a result of sunscreen exposure. ng = not measured

[0124] The data in Table 1 show that the thermoplastic molding compositions produced from the compositions 10 to 16 according to the invention exhibit a surprising, synergistic increase in flexural strength both compared to the pure components A (R2) and B (R4 to R6), compared to non-reactively modified PC or PMMA (R1 and R3) and compared to blends produced from non-reactively modified PC and PMMA (V7) according to the prior art and compared to blends produced from OH-functionalized PC and non-reactively functionalized PMMA (V8 and V9).

[0125] The data also show that the thermoplastic molding compounds produced from the compositions according to the invention have a higher flexural elongation at break than pure non-reactively modified PMMA (R3) and PMMA polymers according to component B (R4-R6).

[0126] Furthermore, the data in Table 1 show that the thermoplastic molding compositions produced from the compositions according to the invention also have a higher transparency (transmission) than analogous non-inventive molding compositions produced from compositions containing non-reactively functionalized PC and / or PMMA (compare inventive examples 10, 12, 13 and 15 with V7 to V9 and V17 to V19).

[0127] The data in Table 1 further show that such molding compositions prepared from compositions containing a component B with a lower ratio M w [kg / mol] / GMA content [wt.%] in the absence of a catalyst have higher transparency and flexural strength than analogous molding compositions prepared from compositions containing a component B with a higher ratio M w [kg / mol] / GMA content [wt.%] of, for example, 60 (compare Example 10 with the preferred Examples 12 and 13).

[0128] On the other hand, the data in Table 1 also show that this technical disadvantage of the molding compositions according to the invention produced from compositions containing a component B with a higher ratio M w [kg / mol] / GMA content [wt.%] of, for example, 60 can be overcome by using zirconium(IV) acetylacetonate as component C (compare Examples 10 and 11), thereby resulting in preferred molding compositions with particularly high transmission.

[0129] The data in Table 1 further show that when using component B with a very high GMA content of, for example, 8 wt.%, based on component B, the addition of zirconium acetylacetonate as component C results in a further increase in flexural strength, but at the same time slightly decreases in transmittance (compare Examples 13 and 15 with Examples 14 and 16). Depending on the exact target property profile sought, the use of zirconium acetylacetonate in such molding compounds produced from compositions containing component B with a very high GMA content can be either technically preferable or less suitable for product development.

[0130] The data in Table 2 demonstrate that similar effects, as previously derived from the data in Table 1, can also be realized in molding compounds and test specimens produced therefrom when the molding compounds are produced on a counter-rotating twin-screw extruder and the test specimens are produced in an injection molding process, as is commonly used in the industrial production of such molding compounds or molded parts. This also demonstrates the good manufacturing and processing stability of the molding compounds according to the invention.

[0131] Furthermore, the data in Table 2 show that the molding compounds according to the invention exhibit a surprising improvement in tensile strength in the tensile test compared to analogous prior art molding compounds produced from compositions containing non-reactive PC and PMMA, and a surprising improvement in modulus in both the tensile and flexural tests. Furthermore, they exhibit improved scratch resistance (pencil hardness) compared to polycarbonate and, in some cases even surprisingly, compared to analogous prior art PC+PMMA molding compounds produced from non-reactive PC and PMMA. This scratch resistance is almost at the level of pure PMMA, even when PMMA component B is used at only 20 wt. % in the PC+PMMA compositions and is therefore not present as a matrix component of the polymer blend (compare Example 22 with Comparative Example C20 or with Reference Examples R24 and R25).

[0132] Furthermore, the data in Table 2 show that the molding compositions according to the invention have improved sunscreen resistance compared to both pure polycarbonate (Reference Example R24) and analogous PC+PMMA molding compositions according to the prior art, which were prepared from compositions containing non-reactive PC and PMMA (Comparative Example 20).

Claims

1. Composition for producing a thermoplastic moulding compound containing A) at least one aromatic polycarbonate and / or aromatic polyester carbonate containing at least 500 ppmw of phenolic OH groups, wherein the weight-average molecular weight Mw of component A determined by gel permeation chromatography at room temperature in dichloromethane as solvent using a BPA polycarbonate standard is in the range from 15 000 to 40 000 g / mol, B) at least one copolymer containing structural units derived from methyl methacrylate and 0.3% to 15% by weight, based on component B, of structural units derived from glycidyl methacrylate, wherein component B has a weight-average molecular weight Mw determined by gel permeation chromatography at room temperature in tetrahydrofuran as solvent using a polystyrene standard of 20 000 to 200 000 g / mol, wherein in component B the ratio of Mw in kg / mol to the weight fraction of glycidyl methacrylate-derived structural units in % by weight is in the range from 2 to 100, wherein the weight ratio of component A and component B is in the range from 30:70 to 90:10.

2. Composition according to Claim 1, wherein in component B the ratio of Mw in kg / mol to the weight fraction of glycidyl methacrylate-derived structural units in % by weight is in the range from 5 to 50.

3. Composition according to either of the preceding claims consisting of 30% to 90% by weight of component A, 10% to 70% by weight of component B and 0% to 20% by weight of polymer additives, processing aids and / or polymers distinct from components A and B as component C, wherein the % by weight amounts of components A to C are chosen such that they sum to 100% by weight.

4. Composition according to Claim 3, wherein component C is a metal acetylacetonate.

5. Composition according to Claim 4, wherein the metal acetylacetonate is zirconium(IV) acetylacetonate and is employed in an amount of 0.01% to 0.2% by weight based on the composition.

6. Composition according to either of the preceding Claims 4 and 5, wherein in component B the ratio of Mw in kg / mol to the weight fraction of glycidyl methacrylate-derived structural units in % by weight is in the range from >50 to 100.

7. Composition according to any of the preceding claims, wherein component B has a weight-average molecular weight Mw measured by gel permeation chromatography at room temperature in tetrahydrofuran as solvent using a polystyrene standard of 50 000 to 80 000 g / mol.

8. Composition according to any of the preceding claims, wherein component A has a proportion of phenolic OH groups of 1500 to 3000 ppmw.

9. Process for producing a thermoplastic moulding compound comprising the steps of (i) melting the constituents of a composition according to any of the preceding claims by introducing thermal energy and / or mechanical shear, (ii) mixing and dispersing the different components of the composition with or in each other, (iii) solidifying the melt by cooling, (iv) granulating the solidified polymer blend resulting from steps (i)-(iii), wherein step (ii) is carried out in a compounding apparatus selected from the group consisting of single-screw extruders, co-rotating or counter-rotating twin-screw extruders, planetary roller extruders, internal kneaders or co-kneaders.

10. Process according to Claim 9, wherein in the process the epoxy groups from component B are partially or completely converted in a chemical reaction.

11. Process according to either of Claims 9 and 10, wherein the process effects a chemical coupling of component A or a portion of component A to component B or a portion of component B.

12. Thermoplastic moulding compound obtainable in a process according to any of Claims 9 to 11.

13. Use of a thermoplastic moulding compound according to Claim 12 for producing moulded articles.

14. Moulded article containing a thermoplastic moulding compound according to Claim 12.

15. Process for producing a moulded article, comprising the steps of (i)metering the constituents of a composition according to any of Claims 1 to 8 into the conveying extruder of an injection moulding machine, (ii)melting the constituents of the composition by introducing thermal energy and / or mechanical shear, (iii)conveying the melt to the discharging point of the extruder, (iv) discharging the melt from the conveying extruder into an injection mould, (v) cooling and solidifying the melt in the injection mould to form a moulded article, (vi) removing the moulded article from the injection mould.