Polycarbonate compositions, articles formed therefrom, and methods for making same

Abstract

A polycarbonate composition comprising specific amounts of a bisphenol A homo-polycarbonate; a first polycarbonate-siloxane copolymer having a siloxane content of from 4 to 10 weight percent based on the total weight of the first polycarbonate-siloxane copolymer; and a second polycarbonate-siloxane copolymer having a siloxane content of greater than 30 to 70 weight percent based on the total weight of the second polycarbonate-siloxane copolymer. The composition can provide a desired combination of properties, including good flame performance, chemical resistance, and aesthetic performance.

Description

[0001] Related Applications

[0002] This application claims priority to and the benefit of European Patent No. 22197822.4 filed on September 26, 2022, the contents of which are incorporated herein by reference in their entirety. Background Art

[0003] The present disclosure relates to polycarbonate compositions, articles formed therefrom, and methods of making the same.The compositions described herein can exhibit advantageous properties, such as improved aesthetic properties, flame retardancy, and improved chemical resistance.

[0004] Polycarbonates are useful in a wide variety of applications, at least in part because of their good balance of properties, such as moldability, heat resistance, and impact properties. Despite extensive research on these materials over the years, there remains a need in the art for improved polycarbonate compositions that meet increasingly stringent industry standards.

[0005] For example, polycarbonate-polysiloxane copolymers can have good mechanical properties and low temperature impact resistance. However, blends of polycarbonate homopolymers with such polycarbonate-polysiloxanes can result in poor aesthetics of molded parts. Aesthetic defects can include excessive haze, limited color space capabilities, pearlescence, or other surface defects associated with molding, such as streaks and flow lines. Previous attempts to improve aesthetics can compromise other desired properties, such as low temperature impact, flame retardancy, and chemical resistance.

[0006]

[0006] Thus, there remains a need in the art for polycarbonate compositions that may possess balanced aesthetics, flame retardancy, and chemical resistance. Summary of the invention

[0007] The polycarbonate composition comprises 20 to 85 weight percent of bisphenol A homopolycarbonate; 10 to 55 weight percent of a first polycarbonate-siloxane copolymer, the first polycarbonate-siloxane copolymer having a siloxane content of 4 to 10 weight percent based on the total weight of the first polycarbonate-siloxane copolymer; and 10 to 25 weight percent of a second polycarbonate-siloxane copolymer, the second polycarbonate-siloxane copolymer having a siloxane content of greater than 30 to 70 weight percent based on the total weight of the second polycarbonate-siloxane copolymer; wherein when the composition has a total siloxane content of 2 to 7.5%, the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer are present in a weight ratio of less than 2; and when the composition has a total siloxane content of greater than 7.5 to 15%, the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer are present in a weight ratio of 2 to 5.

[0008] Another aspect is a method of making a polycarbonate composition comprising melt mixing the components of the composition, and optionally, extruding the composition.

[0009] Another aspect is an article comprising the polycarbonate composition.

[0010] The above described and other features are exemplified by the following detailed description. DETAILED DESCRIPTION

[0011] The present inventors have discovered that a polycarbonate composition comprising a specific amount of bisphenol A homopolycarbonate, a first polycarbonate-siloxane copolymer having a siloxane content of 4 to 10 weight percent based on the total weight of the first polycarbonate-siloxane copolymer, and a second polycarbonate-siloxane copolymer having a siloxane content of greater than 30 to 70 weight percent based on the total weight of the second polycarbonate-siloxane copolymer can provide a combination of desired properties. For example, it has been found that the compositions according to the present disclosure exhibit improved aesthetic properties, flame retardancy, and chemical resistance.

[0012] Therefore, one aspect of the present invention is a polycarbonate composition. The polycarbonate composition comprises bisphenol A homopolycarbonate. The bisphenol A homopolycarbonate has carbonate units of a repeating structure of formula (1).

[0013]

[0014] Bisphenol A polycarbonate homopolymers can be prepared from bisphenol A ((2,2-bis(4-hydroxyphenyl)propane, or BPA) by methods such as interfacial polymerization and melt polymerization, which are known and described, for example, in WO 2013 / 175448 A1 and WO 2014 / 072923 A1. End-capping agents may be included during polymerization to provide end groups, for example, monocyclic phenols such as phenol, p-cyanophenol, and C 1-22Alkyl substituted phenols such as p-cumylphenol, resorcinol monobenzoate, ester and p-tert-butylphenol, monoethers of diphenols such as p-methoxyphenol, monoesters of diphenols such as resorcinol monobenzoate, functionalized chlorides of aliphatic monocarboxylic acids such as acryloyl chloride and methacryloyl chloride, and monochloroformates such as phenyl chloroformate, alkyl substituted phenyl chloroformate, p-cumyl phenyl chloroformate, and toluene chloroformate. Phenol and p-cumylphenol are specifically mentioned. Combinations of different end-capping agents can be used. Branched polycarbonate blocks can be prepared by adding a branching agent during the polymerization process, such as trimellitic acid, trimellitic anhydride, trimellitic acid chloride, tri-p-hydroxyphenylethane, isatin-bisphenol, trisphenol TC (1,3,5-tris((p-hydroxyphenyl)isopropyl)benzene), trisphenol PA (4(4(1,1-bis(p-hydroxyphenyl)-ethyl)α,α-dimethylbenzyl)phenol), 4-chloroformylphthalic anhydride, trimesic acid, and benzophenonetetracarboxylic acid. The branching agent can be added at a level of 0.05 to 4.0 weight percent (wt%), for example, 0.05 to 2.0 wt%. Compositions comprising linear polycarbonates and branched polycarbonates can be used.

[0015] The bisphenol A polycarbonate homopolymer can be a linear bisphenol A polycarbonate homopolymer, optionally end-capped with phenol or p-cumylphenol, and having a weight average molecular weight of 10,000 to 100,000 grams per mole (g / mol), or 10,000 to 75,000 g / mol, or 18,000 to 40,000 g / mol, or 20,000 to 40,000 g / mol, or 28,000 to 38,000 g / mol, as measured by gel permeation chromatography (GPC) using a cross-linked styrene-divinylbenzene column and calibrated relative to a bisphenol A polycarbonate reference. The GPC sample is prepared at a concentration of 1 milligram per milliliter (mg / mL) and eluted at a flow rate of 1.5 ml / min.

[0016] In one aspect, more than one bisphenol A polycarbonate homopolymer may be present. For example, the bisphenol A polycarbonate homopolymer may include a first bisphenol A polycarbonate homopolymer having a first weight average molecular weight, and a second bisphenol A polycarbonate homopolymer having a second weight average molecular weight, wherein the first weight average molecular weight and the second weight average molecular weight are not the same. When present, the weight ratio of the first bisphenol A polycarbonate homopolymer to the second bisphenol A polycarbonate homopolymer may be 10:1 to 1:10, or 5:1 to 1:5, or 3:1 to 1:3, or 2:1 to 1:2.

[0017] Based on the gross weight of the composition, the bisphenol A homopolycarbonate can be present in the composition in an amount of 20 to 85 weight percents. Within this range, the bisphenol A homopolycarbonate can be present in an amount of, for example, 25 to 75 weight percents, or 30 to 70 weight percents, or 30 to 65 weight percents, or 35 to 65 weight percents, or 40 to 65 weight percents, or 45 to 65 weight percents, or 40 to 60 weight percents, or 40 to 55 weight percents, or 30 to 55 weight percents, or 30 to 50 weight percents, or 40 to 50 weight percents, each based on the gross weight of the composition.

[0018] In addition to the bisphenol A homopolycarbonate, the polycarbonate composition further comprises a first polycarbonate-siloxane copolymer and a second polycarbonate-siloxane copolymer. The polycarbonate-siloxane copolymer is also referred to as polycarbonate-siloxane. The first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer both comprise carbonate repeating units and siloxane units. The carbonate units may be derived from dihydroxy aromatic compounds such as bisphenols of formula (2) or diphenols of formula (3):

[0019]

[0020] In formula (2), R a and R b Each is independently C 1-12 Alkyl, C 1-12 Alkenyl, C 3-8 Cycloalkyl, or C 1-12 alkoxy, p and q are each independently 0 to 4, and X a is a single bond, -O-, -S-, -S(O)-, -S(O)2-, -C(O)-, formula -C(R c )(R d )-C 1-11 Alkylene, where R c and R d are independently hydrogen or C 1-10 Alkyl, or -C(=R e )-, wherein R e It is a two-price C 1-10 A hydrocarbon group; and in formula (3), each R h is independently a halogen atom, such as bromine; C 1-10 Hydrocarbon groups such as C 1-10 Alkyl, halogen substituted C 1-10 Alkyl, C 6-10 Aryl or halogen substituted C 6-10 aryl, and n is 0 to 4.

[0021] In one aspect, in formulas (2) and (3), Ra and R b Each is independently C 1-3 Alkyl or C 1-3 alkoxy, p and q are each independently 0 or 1, and X a is a single bond, -O-, -S(O)-, -S(O)2-, -C(O)-, formula -C(R c )(R d )-C 1-11 Alkylene, where R c and R d are independently hydrogen or C 1-10 Alkyl, each R h are independently bromine, C 1-3 Alkyl, halogen substituted C 1-3 An alkyl group, and n is 0 to 1.

[0022] In one aspect, in formulas (2) and (3), R a and R b Each is independently C 1-3 alkyl, p and q are each independently 0 or 1, and X a is a single bond, -O-, -S(O)-, -S(O)2-, -C(O)-, formula -C(R c )(R d )-C 1-11 Alkylene, where R c and R d are independently hydrogen or C 1-10 Alkyl, each R h are independently bromine, C 1-3 Alkyl, halogen substituted C 1-3 alkyl, and n is 0 to 1.

[0023] In one aspect, in formula (2), p and q are each independently 0, and X a is a single bond, -O-, -S(O)-, -S(O)2-, -C(O)-, formula -C(R c )(R d )-C 1-11 Alkylene, where R c and R d are independently hydrogen or C 1-10 alkyl.

[0024] In one aspect, in formula (2), p and q are each independently 0, and X a The formula is -C(R c )(R d )-C 1-11 Alkylene, where R c and R dare independently hydrogen or C 1-10 alkyl.

[0025] In one aspect, in formula (2), p and q are each independently 0, and X a It is of formula -C(R c )(R d )-C 1-11 Alkylene, where R c and R d Each independently is C 1-10 Alkyl group, preferably methyl group.

[0026] Examples of the bisphenol compound (2) include BPA, 4,4'-dihydroxybiphenyl, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, bis(4-hydroxyphenyl)methane, bis(4-hydroxyphenyl)diphenylmethane, bis(4-hydroxyphenyl)-1-naphthylmethane, 1,2-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2-(4-hydroxyphenyl)-2-(3-hydroxyphenyl)propane, bis(4-hydroxyphenyl)phenylmethane, 2,2-bis(4-hydroxy-3-bromophenyl)propane, 1,1-bis(hydroxyphenyl)cyclopentane, 1,1-bis(4-hydroxyphenyl)cyclohexane, 1,1-bis(4-hydroxyphenyl)isothiazolidine, 1,2-bis(4-hydroxyphenyl)ethane, 1,1-bis(4-hydroxyphenyl)-1-phenylethane, 2-(4-hydroxyphenyl)-2-(3-hydroxyphenyl)propane, bis(4-hydroxyphenyl)phenylmethane, 2,2-bis(4-hydroxy-3-bromophenyl)propane, Butene, 1,1-bis(4-hydroxyphenyl)cyclododecane, trans-2,3-bis(4-hydroxyphenyl)-2-butene, 2,2-bis(4-hydroxyphenyl)adamantane, α,α'-bis(4-hydroxyphenyl)toluene, bis(4-hydroxyphenyl)acetonitrile, 2,2-bis(3-methyl-4-hydroxyphenyl)propane, 2,2-bis(3-ethyl-4-hydroxyphenyl)propane, 2,2-bis(3-n-propyl-4-hydroxyphenyl)propane, 2,2-bis(3-isopropyl-4-hydroxyphenyl)propane, 2,2-bis(3-sec-butyl-4-hydroxyphenyl)propane, 2,2-bis(3-tert-butyl-4-hydroxyphenyl)propane, 2,2-bis(3-cyclohexyl- 4-hydroxyphenyl)propane, 2,2-bis(3-allyl-4-hydroxyphenyl)propane, 2,2-bis(3-methoxy-4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)hexafluoropropane, 1,1-dichloro-2,2-bis(4-hydroxyphenyl)ethylene, 1,1-dibromo-2,2-bis(4-hydroxyphenyl)ethylene, 1,1-dichloro-2,2-bis(5-phenoxy-4-hydroxyphenyl)ethylene, 4,4'-dihydroxybenzophenone, 3,3-bis(4-hydroxyphenyl)-2-butanone, 1,6-bis(4-hydroxyphenyl)-1,6-hexanedione, ethylene glycol bis(4-hydroxyphenyl) ether, bis(4-hydroxyphenyl) ether, bis(4-hydroxyphenyl) The present invention also includes bis(4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfoxide, bis(4-hydroxyphenyl)sulfone, 9,9-bis(4-hydroxyphenyl)fluorene, 2,7-dihydroxypyrene, 6,6'-dihydroxy-3,3,3',3'-tetramethylspiro(bis)indane (spirobiindane bisphenol), 3,3-bis(4-hydroxyphenyl)phthalimide, 2,6-dihydroxydibenzo-p-dioxin, 2,6-dihydroxythianthrene, 2,7-dihydroxyphenoxathin, 2,7-dihydroxy-9,10-dimethylphenazine, 3,6-dihydroxydibenzofuran, 3,6-dihydroxydibenzothiophene, and 2,7-dihydroxycarbazole. Combinations comprising different bisphenol compounds may be used.

[0027] Examples of the diphenol compound (3) include resorcinol, substituted resorcinol compounds such as 5-methylresorcinol, 5-ethylresorcinol, 5-propylresorcinol, 5-butylresorcinol, 5-tert-butylresorcinol, 5-phenylresorcinol, 5-cumylresorcinol, 2,4,5,6-tetrafluororesorcinol, 2,4,5,6-tetrabromoresorcinol, etc.; catechol; hydroquinone; substituted hydroquinones such as 2-methylhydroquinone, 2-ethylhydroquinone, 2-propylhydroquinone, 2-butylhydroquinone, 2-tert-butylhydroquinone, 2-phenylhydroquinone, 2-cumylhydroquinone, 2,3,5,6-tetramethylhydroquinone, 2,3,5,6-tetra-tert-butylhydroquinone, 2,3,5,6-tetrafluorohydroquinone, 2,3,5,6-tetrabromohydroquinone, etc. A combination comprising different diphenol compounds may be used.

[0028] In one aspect, the carbonate units may be bisphenol carbonate units derived from a bisphenol of formula (2). A preferred bisphenol is bisphenol A (BPA).

[0029] The siloxane units (also referred to as polysiloxane blocks) are optionally of formula (4):

[0030]

[0031] Where each R is independently C 1-13 A monovalent organic group. For example, R can be C 1-13 Alkyl, C 1-13 Alkoxy, C 2-13 Alkenyl, C 2-13 Alkenyloxy, C 3-6 Cycloalkyl, C 3-6 Cycloalkoxy, C 6-14 Aryl, C 6-10 Aryloxy, C 7-13 Arylalkylene, C 7-13 Arylalkyleneoxy, C 7-13 Alkyl arylene, or C 7-13 Alkyl aryleneoxy. The above groups can be completely or partially halogenated with fluorine, chlorine, bromine, or iodine, or a combination thereof. In one aspect, when a transparent poly(carbonate-siloxane) is desired, R is not substituted with a halogen. Combinations of the foregoing R groups can be used in the same copolymer.

[0032] In one aspect, R is C 1-3 Alkyl, C 1-3 Alkoxy, C 3-6 Cycloalkyl, C 3-6 Cycloalkoxy, C 6-14 Aryl, C 6-10In one aspect, R is methyl, trifluoromethyl, or phenyl, preferably methyl.

[0033] The value of E in formula (4) can vary widely, depending on the type and relative amounts of the components in the polycarbonate composition, the desired properties of the composition, and the like. Typically, E has an average value of 2 to 1,000, or 2 to 500, 2 to 200, or 2 to 125, 5 to 80, or 10 to 70. In one aspect, E has an average value of 10 to 80 or 10 to 40, in another aspect, E has an average value of 40 to 80 or 40 to 70, and in yet another aspect, E has an average value of 10 to 100, or 20 to 60, or 30 to 50.

[0034] In one aspect, the siloxane unit is of formula (5)

[0035]

[0036] wherein E is as defined above in the context of formula (4); each R may be the same or different and is as defined above in the context of formula (4); and Ar may be the same or different and is substituted or unsubstituted C 6-30 Arylene, wherein the bond is directly attached to the aromatic moiety. The Ar group in formula (5) can be derived from C 6-30 A dihydroxyarylene compound, such as a dihydroxy compound of formula (3). Exemplary dihydroxyarylene compounds are 1,1-bis(4-hydroxyphenyl)methane, 1,1-bis(4-hydroxyphenyl)ethane, 2,2-bis(4-hydroxyphenyl)propane, 2,2-bis(4-hydroxyphenyl)butane, 2,2-bis(4-hydroxyphenyl)octane, 1,1-bis(4-hydroxyphenyl)propane, 1,1-bis(4-hydroxyphenyl)n-butane, 2,2-bis(4-hydroxy-1-methylphenyl)propane, 1,1-bis(4-hydroxyphenyl)cyclohexane, bis(4-hydroxyphenyl sulfide), and 1,1-bis(4-hydroxy-tert-butylphenyl)propane, or combinations thereof.

[0037] Specific examples of the siloxane unit of formula (5) include those of formula (5a) and formula (5b).

[0038]

[0039] In one aspect, the siloxane unit is of formula (6)

[0040]

[0041] wherein R and E are as described above in the context of formula (4), and each R 5 Independently divalent C1-30 In one aspect, the polydiorganosiloxane block is of formula (7):

[0042]

[0043] wherein R and E are as defined above in the context of formula (4). 6 It is a two-price C 2-8 Each M in formula (7) may be the same or different and may be halogen, cyano, nitro, C 1-8 Alkylthio, C 1-8 Alkyl, C 1-8 Alkoxy, C 2-8 Alkenyl, C 2-8 Alkenyloxy, C 3-8 Cycloalkyl, C 3-8 Cycloalkoxy, C 6-10 Aryl, C 6-10 Aryloxy, C 7-12 Aralkyl, C 7-12 Arylalkyleneoxy, C 7-12 Alkyl arylene, or C 7-12 Alkylaryleneoxy, wherein each n is independently 0, 1, 2, 3 or 4.

[0044] In one aspect, M is bromo or chloro, alkyl such as methyl, ethyl, or propyl, alkoxy such as methoxy, ethoxy, or propoxy, or aryl such as phenyl, chlorophenyl, or tolyl; R 6 is ethylene, propylene or butylene; and R is C 1-8 In one aspect, R is methyl, or a combination of methyl and trifluoropropyl, or a combination of methyl and phenyl. In one aspect, R is methyl, M is methoxy, n is 1, and R 6 It is a two-price C 1-3 The specific polydiorganosiloxane block is of the formula

[0045]

[0046] or a combination thereof, wherein E has an average value of 10 to 100, preferably 20 to 60, more preferably 30 to 50, or 40 to 50.

[0047] The blocks of formula (7) can be derived from the corresponding dihydroxy polydiorganosiloxanes by known methods. Polycarbonate-siloxanes can be prepared by introducing phosgene into a mixture of bisphenol and end-capped polydimethylsiloxane (PDMS) under interfacial reaction conditions. Other known methods can also be used.

[0048] In one aspect, the poly(carbonate-siloxane) comprises carbonate units derived from bisphenol A, and repeating siloxane units (5a), (5b), (7a), (7b), (7c), or a combination thereof (preferably Formula 7a), wherein E has an average value of 10 to 100, preferably 20 to 80, or 30 to 70, more preferably 30 to 50 or 40 to 50.

[0049] The present inventors have unexpectedly discovered that polycarbonate compositions can exhibit a combination of desirable properties, including good chemical resistance, flame retardancy, and aesthetic properties, when specific combinations of polycarbonate-siloxane copolymers are used in the composition.

[0050] The first polycarbonate-siloxane copolymer can have a siloxane content of 4 to 10 weight percent based on the gross weight of the first polycarbonate-siloxane copolymer. Within this range, the first polycarbonate-siloxane copolymer can have a siloxane content of 5 to less than 10 weight percent, or 5 to 9 weight percent, or 4 to 9 weight percent, or 4 to 8 weight percent, or 5 to 8 weight percent, or 5 to 7 weight percent. As used herein, the "siloxane content" of a poly(carbonate-siloxane) refers to the content of siloxane units based on the gross weight of the polycarbonate-siloxane copolymer.

[0051] The second polycarbonate-siloxane copolymer can have a siloxane content of 30 to 70 weight percent based on the total weight of the second polycarbonate-siloxane copolymer. Within this range, the second polycarbonate-siloxane copolymer can have a siloxane content of 35 to 65 weight percent, or 35 to 60 weight percent, or 30 to 50 weight percent, or 35 to 55 weight percent, or 35 to 45 weight percent.

[0052] The first polycarbonate-siloxane copolymer can have a weight average molecular weight of 10,000 to 50,000 g / mol, or 15,000 to 40,000 g / mol, or 20,000 to 30,000 g / mol, or 20,000 to 25,000 g / mol as measured by gel permeation chromatography using a cross-linked styrene-divinylbenzene column at a sample concentration of 1 mg / ml and as calibrated using bisphenol A polycarbonate standards.

[0053] The second polycarbonate-siloxane copolymer can have a weight average molecular weight of 21,000 to 50,000 g / mol. Within this range, the weight average molecular weight can be 25,000 to 45,000 g / mol, or 30,000 to 45,000 g / mol, or 32,000 to 43,000 g / mol, or 34,000 to 41,000 g / mol, or 35,000 to 40,000 g / mol. A cross-linked styrene-divinylbenzene column can be used to measure the weight average molecular weight by gel permeation chromatography at a sample concentration of 1 mg / ml, and as calibrated using a bisphenol A polycarbonate standard.

[0054] In one aspect, the composition comprises less than 5 wt % or less than or equal to 1 wt %, or less than or equal to 0.1 wt % of a polycarbonate-siloxane having a siloxane content of greater than 10 to less than 30 wt %, such as 12 to 28 wt %. Preferably, polycarbonate-siloxanes having a siloxane content of greater than 10 to less than 30 weight percent, such as 12 to 28 weight percent are excluded from the composition.

[0055] The first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer can be present in the composition in an amount to provide a total siloxane content of 2 to 15 weight percent, or 2 to 12 weight percent, or 2 to 10 weight percent, or 2 to 7.5 weight percent, or 7.5 to 15 weight percent, each based on the total weight of the polycarbonate composition. In one aspect, the composition can have a total siloxane content of 2 to 7.5 weight percent, and the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer can be present in a weight ratio of less than 2 (i.e., less than 2:1), such as less than 1.75, or less than 1.5, or 0.75:1 to 1.5:1, or 0.9:1 to 1.2:1. In one aspect, the composition can have a total siloxane content of greater than 7.5 to 15 weight percent, and the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer can be present in a weight ratio of 1.5 to 5 or 2 to 5 (i.e., 2:1 to 5:1), e.g., 1.5:1 to 5:1, or 2:1 to 4:1, or 2:1 to 3:1.

[0056] The first polycarbonate-siloxane copolymer can be present in the composition in an amount of 10 to 55 weight percent, based on the total weight of the composition. Within this range, the first polycarbonate-siloxane copolymer can be present in an amount of, for example, 10 to 50 weight percent, or 15 to 50 weight percent, or 15 to 45 weight percent, or 20 to 45 weight percent, or 20 to 40 weight percent, or 15 to 40 weight percent, or 25 to 35 weight percent, each based on the total weight of the composition.

[0057] The second polycarbonate-siloxane copolymer can be present in the composition in an amount of 10 to 25 weight percent, based on the total weight of the composition. Within this range, the second polycarbonate can be present in an amount of, for example, greater than 10 to 25 weight percent, or 15 to 25 weight percent, or greater than 15 to 25 weight percent, or 16 to 25 weight percent, or 17 to 25 weight percent, or 18 to 25 weight percent, or 15 to 20 weight percent, or greater than 15 to 20 weight percent, or 17 to 20 weight percent, each based on the total weight of the composition.

[0058] In one aspect, one or more of the bisphenol A homopolycarbonate, the first polycarbonate-siloxane copolymer, and the second polycarbonate-siloxane copolymer can be derived from post-consumer recycled or post-industrial recycled materials. In one aspect, one or more of the bisphenol A homopolycarbonate, the first polycarbonate-siloxane copolymer, and the second polycarbonate-siloxane copolymer can be produced from at least one monomer derived from a bio-based or plastic waste feedstock.

[0059] Polycarbonate composition can optionally further include an additive composition comprising one or more additives that are usually incorporated into this type of polymer composition, provided that one or more additives are selected to not significantly adversely affect the desired properties of the polycarbonate composition, especially impact, chemical resistance, and flame retardancy.Additives can include fillers, reinforcing agents, antioxidants, heat stabilizers, light stabilizers, ultraviolet (UV) light stabilizers, plasticizers, lubricants, mold release agents, antistatic agents, colorants such as titanium dioxide, carbon black and organic dyes, surface effect additives, radiation stabilizers, flame retardants, and anti-dripping agents.A combination of additives can be used, such as a combination of heat stabilizers, mold release agents, and ultraviolet light stabilizers.Usually, additives are used in a known effective amount.For example, based on the gross weight of the polycarbonate composition, the total amount of additives (except any impact modifier, filler, or reinforcing agent) can be 0.01 to 5 weight percents.In one aspect, based on the weight of the composition, the polycarbonate composition includes processing aids, heat stabilizers, antioxidants, ultraviolet light absorbers, colorants, or combinations thereof that are no more than 5 weight percents.

[0060] In one aspect, the composition may optionally further comprise a flame retardant. Useful flame retardants may include organic compounds containing phosphorus, bromine, or chlorine. For regulatory reasons, non-brominated and non-chlorinated phosphorus-containing flame retardants may be preferred in certain applications, for example, organic phosphates and organic compounds containing phosphorus-nitrogen bonds.

[0061] Flame retardant aromatic phosphates include triphenyl phosphate, tricresyl phosphate, isopropylated triphenyl phosphate, phenyl bis(dodecyl) phosphate, phenyl bis(neopentyl) phosphate, phenyl bis(3,5,5'-trimethylhexyl) phosphate, ethyl diphenyl phosphate, 2-ethylhexyl di(p-tolyl) phosphate, bis(2-ethylhexyl) p-tolyl phosphate, tricresyl phosphate, bis(2-ethylhexyl) phenyl phosphate, tri(nonylphenyl) phosphate, bis(dodecyl) p-tolyl phosphate, dibutylphenyl phosphate, 2-chloroethyl diphenyl phosphate, p-tolyl bis(2,5,5'-trimethylhexyl) phosphate, and 2-ethylhexyl diphenyl phosphate. Also useful are di- or polyfunctional aromatic phosphorus-containing compounds, such as resorcinol tetraphenyl diphosphate (RDP), the bis(diphenyl)phosphate ester of hydroquinone, and the bis(diphenyl)phosphate ester of bisphenol A, respectively, and their oligomeric and polymeric counterparts.

[0062] Flame retardant compounds containing phosphorus-nitrogen bonds include phosphazenes, phosphazene chlorides, phosphorus esteramides, phosphoric acid amides, phosphonic acid amides, phosphinic acid amides, and tri(aziridinyl)phosphine oxide. These flame retardant additives are commercially available.

[0063] Halogenated materials can also be used as flame retardants, such as the following representative bisphenols: 2,2-bis-(3,5-dichlorophenyl)-propane; bis-(2-chlorophenyl)-methane; bis-(2,6-dibromophenyl)-methane; 1,1-bis-(4-iodophenyl)-ethane; 1,2-bis-(2,6-dichlorophenyl)-ethane; 1,1-bis-(2-chloro-4-iodophenyl)-ethane; 1,1-bis-(2-chloro-4-methylphenyl)-ethane; 1,1-bis-(3,5-dichlorophenyl)-ethane; 2,2-bis-(3-phenyl-4-bromophenyl)-ethane; 2,6-bis-(4,6-dichloronaphthyl)-propane; and 2,2-bis-(3,5-dichloro-4-hydroxyphenyl)-propane; 2,2-bis-(3-bromo-4-hydroxyphenyl)-propane. Other halogenated materials include 1,3-dichlorobenzene, 1,4-dibromobenzene, 1,3-dichloro-4-hydroxybenzene, and biphenyls such as 2,2'-dichlorobiphenyl, polybrominated 1,4-diphenoxybenzene, 2,4'-dibromobiphenyl, and 2,4'-dichlorobiphenyl and decabromodiphenyl ether, and oligomeric and polymeric halogenated aromatic compounds such as copolycarbonates of bisphenol A and tetrabromobisphenol A with carbonate precursors (e.g., phosgene). Metal synergists, such as antimony oxide, can also be used with flame retardants.

[0064] Alternatively, the thermoplastic composition can be substantially free of chlorine and bromine. "Substantially free of chlorine and bromine" is defined as having a bromine or chlorine content of less than or equal to 100 parts per million (ppm), less than or equal to 75 ppm, or less than or equal to 50 ppm by weight, based on the total weight of the composition.

[0065] Inorganic flame retardants such as C 1-16 Alkyl sulfonates such as potassium perfluorobutanesulfonate (Rimar salt), potassium perfluorooctanesulfonate, tetraethylammonium perfluorohexanesulfonate, and potassium diphenylsulfonesulfonate; salts such as Na2CO3, K2CO3, MgCO3, CaCO3 and BaCO3, or fluoride anion complexes such as Li3AlF6, BaSiF6, KBF4, K3AlF6, KAlF4, K2SiF6 or Na3AlF6.

[0066] When present, the flame retardant can be included in the composition in an amount of 0.01 to 10 weight percent. Within this range, the flame retardant can be present in an amount of 0.1 to 10 weight percent, or 1 to 10 weight percent, or 1 to 8 weight percent, or 2 to 6 weight percent, or 3 to 5 weight percent, each based on the gross weight of the composition. In one aspect, when the flame retardant comprises an inorganic flame retardant, the flame retardant can be present in an amount of 0.05 to 1 weight percent.

[0067] The heat stabilizer additive may include an organic phosphite (e.g., triphenylphosphite, tris-(2,6-dimethylphenyl)phosphite, tris-(mixed mono- and dinonylphenyl)phosphite, etc.), a phosphonate (e.g., dimethylphenylphosphonate, etc.), a phosphate (e.g., trimethyl phosphate, etc.), or a combination thereof. The heat stabilizer may be tris(2,4-di-tert-butylphenyl)phosphate available as IRGAPHOS168. The heat stabilizer is typically used in an amount of 0.01 to 5 wt % based on the total weight of the polymer of the composition.

[0068] Light stabilizers or ultraviolet (UV) absorbing additives, also known as UV stabilizers, may also be used. Light stabilizer additives include benzotriazoles such as 2-(2-hydroxy-5-methylphenyl)benzotriazole, 2-(2-hydroxy-5-tert-octylphenyl)-benzotriazole, and 2-hydroxy-4-n-octyloxybenzophenone, or a combination thereof.

[0069] UV absorbing additives include hydroxybenzophenones; hydroxybenzotriazoles; hydroxybenzotriazines; cyanoacrylates; oxanilides; benzoxazinones; aryl salicylates; monoesters of diphenols, such as resorcinol monobenzoate; 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)-phenol (CYASORB 5411); 2-hydroxy-4-n-octyloxybenzophenone (CYASORB 531); 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-(octyloxy)-phenol (CYASORB 5411); 1164); 2,2'-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one) (CYASORBUV-3638); poly[(6-morpholino-s-triazine-2,4-diyl)[2,2,6,6-tetramethyl-4-piperidinyl)imino]-hexamethylene[(2,2,6,6-tetramethyl-4-piperidinyl)imino], 2-hydroxy-4-octyloxybenzophenone (UVINUL TM 3008), 6-tert-butyl-2-(5-chloro-2H-benzotriazol-2-yl)-4-methylphenyl (UVINUL TM 3026), 2,4-di-tert-butyl-6-(5-chloro-2H-benzotriazol-2-yl)-phenol (UVINUL TM3027), 2-(2H-benzotriazol-2-yl)-4,6-di-tert-butylphenol (UVINUL3028), 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)-phenol (UVINUL3029), 1,3-bis[(2'cyano-3',3'-diphenylacryloyl)oxy]-2,2-bis-{[(2'-cyano-3',3'-diphenylacryloyl)oxy]methyl}-propane (UVINUL3030), 2-(2H-benzotriazol-2-yl)-4-methylphenol (UVINUL3033), 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (UVINUL3034), 2-cyano-3,3-diphenylacrylate (UVINUL3036), UL3035), (2-ethylhexyl)-2-cyano-3,3-diphenylacrylate (UVINUL3039), N,N'-bisformyl-N,N'-bis(2,2,6,6-tetramethyl-4-piperidinyl)hexamethylenediamine (UVINUL4050H), bis-(2,2,6,6-tetramethyl-4-piperidinyl)-sebacate (UVINUL4077H), bis-(1,2,2,6,6-pentamethyl-4-piperidinyl)-sebacate + methyl-(1,2,2,6,6-pentamethyl-4-piperidinyl)-sebacate (UVINUL4092H), 1,3-bis[(2-cyano-3,3-diphenylacryloyl)oxy]-2,2-bis[[(2-cyano-3,3-diphenylacryloyl)oxy]methyl]propane (UVINUL 3030); 2,2'-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one); 1,3-bis[(2-cyano-3,3-diphenylacryloyl)oxy]-2,2-bis[[(2-cyano-3,3-diphenylacryloyl)oxy]methyl]propane; TINUVIN234; nano-sized inorganic materials such as titanium oxide, cerium oxide and zinc oxide each having a particle size of less than or equal to 100 nanometers; and the like, or a combination thereof. The UV absorber may be used in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the polycarbonate and the impact modifier. UV absorbers that may be particularly suitable for the polycarbonate compositions disclosed herein include 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)-phenol (e.g., CYASORB TM5411, commercially available from Cytec Industries, Inc., Woodland Park, New Jersey) and 2,2'-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one) (e.g., CYASORB UV-3638, commercially available from Cytec Industries, Inc., Woodland Park, New Jersey), or a combination thereof. The UV stabilizer may be present in an amount of 0.01 to 1 wt%, preferably 0.1 to 0.5 wt%, and more preferably 0.15 to 0.4 wt%, based on the total weight of the polycarbonate composition.

[0070] Plasticizers, lubricants, or mold release agents may also be used. There is considerable overlap in these types of materials, including, for example, phthalates such as dioctyl-4,5-epoxy-hexahydrophthalate; tris-(octyloxycarbonylethyl) isocyanurate; tristearate; di- or polyfunctional aromatic phosphates such as resorcinol tetraphenyl diphosphate (RDP), bis(diphenyl) phosphate of hydroquinone, and bis(diphenyl) phosphate of bisphenol A; poly-alpha-olefins; epoxidized soybean oil; silicones, including silicones. Oils; esters, for example, fatty acid esters such as alkyl stearates, for example, methyl stearate, stearyl stearate, pentaerythritol tetrastearate, and the like; methyl stearate in combination with hydrophilic and hydrophobic nonionic surfactants comprising polyethylene glycol polymers, polypropylene glycol polymers, poly(ethylene glycol-co-propylene glycol) copolymers, or combinations thereof, for example, methyl stearate and polyethylene glycol-polypropylene glycol copolymers in a suitable solvent; waxes such as beeswax, montan wax, paraffin wax, and the like.

[0071] Anti-drip agents, such as fibril-forming or non-fibril-forming fluoropolymers such as polytetrafluoroethylene (PTFE), may also be used in the composition. The anti-drip agent may be encapsulated by a rigid copolymer, such as a styrene-acrylonitrile copolymer (SAN). PTFE encapsulated in SAN is referred to as TSAN. TSAN contains 50 wt % PTFE and 50 wt % SAN, based on the total weight of the encapsulated fluoropolymer. SAN may contain, for example, 75 wt % styrene and 25 wt % acrylonitrile, based on the total weight of the copolymer. The anti-drip agent may be used in an amount of 0.1 to 5 weight percent, or 0.1 to 2 weight percent, based on the total weight of the composition.

[0072] In one aspect, polycarbonate can include colorant composition. Suitable colorant can include but not limited to those known by its color index, such as solvent green 3, solvent green 28, solvent red 52, solvent red 111, solvent red 135, solvent red 169, solvent red 179, solvent red 207, disperse red 22, vat red 41, solvent orange 60, solvent orange 63, solvent violet 13, solvent violet 14, solvent violet 50, amino ketone black, solvent black 7, nigrosine dye, disperse blue 73, solvent blue 97, solvent blue 101, solvent blue 104, solvent blue 138, disperse yellow 160, solvent yellow 84, solvent yellow 93, solvent yellow 98, solvent yellow 163, solvent yellow 160:1, and the mixture comprising at least one of the aforementioned colorants. Preferred colorant can include solvent red 135, solvent yellow 163, solvent green 3, and the mixture comprising at least one of the aforementioned colorants.

[0073] Colorants can be used in amounts and combinations sufficient to darken and opaque the molded article, and more specifically to provide the brightness values ​​described below. The specific amount of the colorant used can depend, among other factors, on its solubility and extinction coefficient in the polycarbonate composition, and whether it is used in combination with one or more additional colorants. Suitable amounts and combinations can be easily determined by one of ordinary skill in the art guided by the present disclosure. The amount of a typical colorant can be, for example, 0.1 to 1 weight percent based on the total weight of the composition, for example, 0.5 to 1 weight percent based on the total weight of the composition.

[0074] In one aspect, when present, the colorant composition can provide a polycarbonate composition having a black color. For example, a dye combination providing a black color can include a green dye and a red dye. In one aspect, when two dyes are used to provide a black dye, the dyes can be used in a weight ratio of 1:99 to 99:1.

[0075] In one aspect, the composition may include an additive composition comprising 0.05 to 1 weight percent of an inorganic flame retardant, preferably comprising C 1-16 Sulfonates, more preferably potassium perfluorobutanesulfonate, potassium perfluorooctanesulfonate, tetraethylammonium perfluorohexanesulfonate, and potassium diphenylsulfonesulfonate, or combinations thereof; and optionally 0.01 to 1 weight percent of an anti-drip additive.

[0076] The polycarbonate composition may optionally exclude other components not specifically described herein. For example, the polycarbonate composition may exclude thermoplastic polymers other than bisphenol A homopolycarbonate, and the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer. For example, the composition may minimize or exclude polyesters (e.g., polyesters may be present in an amount of 1 weight percent or less, preferably, wherein polyesters are excluded from the composition). The composition may optionally exclude polycarbonates other than bisphenol A homopolycarbonate and polycarbonate-siloxane copolymers, such as polyester-carbonates or bisphenol A copolycarbonates different from polycarbonate-siloxane copolymers. The polycarbonate composition may optionally exclude impact modifiers, such as silicone-based impact modifiers different from poly (carbonate-siloxane) copolymers, methyl methacrylate-butadiene-styrene copolymers, acrylonitrile-butadiene, styrene copolymers, etc., or combinations thereof. The composition can exclude halogenated flame retardants, such as brominated flame retardants, including brominated polycarbonates (e.g., polycarbonates containing brominated carbonates contain units derived from 2,2',6,6'-tetrabromo-4,4'-isopropylidene diphenol (TBBPA) and carbonate units derived from at least one dihydroxy aromatic compound that is not TBBPA), brominated epoxy resins, etc., or combinations thereof. The composition can optionally exclude inorganic flame retardants. The composition can optionally exclude phosphorus-containing flame retardants.

[0077] The composition can advantageously exhibit one or more desired properties. For example, each having a specific siloxane content, it is found that by combining bisphenol A homopolycarbonate with the first polycarbonate-siloxane and the second polycarbonate-siloxane, improved chemical resistance can be unexpectedly obtained. These compositions can have balanced performance, including two or more of chemical resistance, flame retardancy and improved color. Without wishing to be bound by theory, it is believed that by carefully selecting and balancing the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer used in the composition, including selecting the weight percentage of siloxane units in the polycarbonate-siloxane, an unexpected combination of chemical resistance, flame retardancy and color is achieved.

[0078] The composition can have good chemical resistance. In an exemplary aspect, after exposing an ISO tensile bar to the sunscreen for 72 hours at 1% strain at a temperature of 23°C, the polycarbonate composition can have a tensile strain at break of at least 50% of the tensile strain at break of an unexposed reference tested at the same temperature.

[0079] The polycarbonate composition can further have good flame retardant properties. In terms of measuring flame retardancy, the UL94 standard uses a grade of V0, V1, V2 or HB, wherein the grade of V0 is better than V1 or V2 and the V0 grade is required for the application of a variety of actual component thicknesses. Using this standard, the polycarbonate composition is formed into a molded article with a given thickness. The thinner the article, the more difficult it is to achieve a grade of V0 or V1. In one aspect, the molded sample of the polycarbonate composition can achieve a V0 or V1 grade of UL-94 at a thickness of 1.5 millimeters or less, preferably, a V0 or V1 grade of UL-94 at a thickness of less than or equal to 1.2 millimeters.

[0080] The polycarbonate composition can further exhibit good color. For example, the polycarbonate composition can have an L* value of less than or equal to 10, or less than or equal to 8, or less than or equal to 7, or less than or equal to 6, as measured by the CIE Lab method, using a 10 degree observer, a D65 light source, removing the specular component, and in reflection mode, and using a sample having a thickness of 3.2 mm.

[0081] The polycarbonate composition may further have a good melt viscosity, which facilitates processing. The polycarbonate composition may have a melt volume rate (MVR, cubic centimeters per 10 minutes (cm3) measured according to ISO 1133 at 300°C for 300 seconds under a load of 2.16 kg of 4 to 20 or 7 to 15, greater than or equal to 4, or greater than or equal to 5. 3 / 10min)).

[0082] The polycarbonate composition may have a heat distortion temperature (HDT) of 110° C. or higher measured at 1.82 MPa on a sample plate having a thickness of 4 mm according to ASTM D648.

[0083] In one aspect, the polycarbonate composition can advantageously exhibit the above UL-94 rating and tensile elongation retention, and can optionally further exhibit one or more of the above heat distortion temperature and melt volume flow rate.

[0084] In one aspect, the polycarbonate composition can have an L* value less than or equal to 10, a tensile strain at break after exposure to a sunscreen that is at least 50% of the tensile strain at break of an unexposed reference sample, and a UL-94 flame rating of V0 or V1 at a thickness of 1.5 mm or less, preferably a UL-94 flame rating of V0 or V1 at a thickness of 1.2 mm or less.

[0085] The polycarbonate composition according to the present disclosure may include 20 to 85 weight percent of bisphenol A homopolycarbonate; 10 to 55 weight percent of a first polycarbonate-siloxane copolymer, the first polycarbonate-siloxane copolymer having a siloxane content of 4 to 10 weight percent based on the total weight of the first polycarbonate-siloxane copolymer; and 10 to 25 weight percent of a second polycarbonate-siloxane copolymer, the second polycarbonate-siloxane copolymer having a siloxane content of greater than 30 to 70 weight percent based on the total weight of the second polycarbonate-siloxane copolymer. The composition may have a total siloxane content of 2 to 7.5%, and the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer may be present in a weight ratio of less than 2. The composition may have a total siloxane content of greater than 7.5 to 15%, and the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer may be present in a weight ratio of 2 to 5. Bisphenol A homopolycarbonate can have a weight average molecular weight of 18,000 to 40,000 g / mole, or 20,000 to 40,000 g / mole, or 28,000 to 38,000 g / mole, as measured by gel permeation chromatography and relative to a linear bisphenol A polycarbonate standard. Based on the total weight of the first polycarbonate-siloxane copolymer, the first polycarbonate-siloxane copolymer can have a siloxane content of 4 to 8 weight percent. Based on the total weight of the composition, the first polycarbonate-siloxane copolymer can be present in an amount of 15 to 45 weight percent. Based on the total weight of the second polycarbonate-siloxane copolymer, the second polycarbonate-siloxane copolymer can have a siloxane content of 35 to 65 weight percent. Based on the total weight of the composition, the second polycarbonate-siloxane copolymer can be present in the composition in an amount greater than 15 to 25 weight percent, or 17 to 25 weight percent. The composition can include less than 5 weight percent, or less than 1 weight percent, or preferably exclude polycarbonate-siloxane copolymers having a siloxane content greater than 10 to less than 30 weight percent. The first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer can each include bisphenol A carbonate repeating units and poly (dimethylsiloxane) repeating units. The second polycarbonate-siloxane copolymer can have a weight average molecular weight of 21,000 g / mol to 50,000 g / mol, or 25,000 g / mol to 45,000 g / mol, or 30,000 g / mol to 45,000 g / mol, or 32,000 g / mol to 43,000 g / mol, or 35,000 g / mol to 40,000 g / mol, as measured by gel permeation chromatography at a sample concentration of 1 mg / ml using a crosslinked styrene-divinylbenzene column, and as calibrated using bisphenol A polycarbonate standards.The polycarbonate composition may further comprise 0.1 to 10 weight percent of the additive composition, based on the total weight of the polycarbonate composition. A molded sample of the composition may exhibit one or more of the following: an L* value less than or equal to 10; or a tensile strain at break of at least 50% of the tensile strain at break of an unexposed reference sample after exposure to a sunscreen or insect repellent; or a UL-94 flammability rating of V0 or V1 at a thickness of 1.5 mm or less, preferably a UL-94 flammability rating of V0 or V1 at a thickness of 1.2 mm or less.

[0086] In one aspect, the polycarbonate composition may include 50 to 60 weight percent of bisphenol A homopolycarbonate; 25 to 35 weight percent of the first polycarbonate-siloxane copolymer; and 15 to 20 weight percent of the second polycarbonate-siloxane copolymer. In one aspect, the bisphenol A homopolycarbonate may have a weight average molecular weight of 28,000 to 38,000 grams per mole, as measured by gel permeation chromatography relative to a linear bisphenol A polycarbonate standard. Based on the total weight of the first polycarbonate-siloxane copolymer, the first polycarbonate-siloxane copolymer may have a siloxane content of 4 to 8 weight percent. Based on the total weight of the second polycarbonate-siloxane copolymer, the second polycarbonate-siloxane copolymer may have a siloxane content of 35 to 65 weight percent. The composition may include less than 1 weight percent of a polycarbonate-siloxane copolymer having a siloxane content of greater than 10 to less than 30 weight percent. The first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer may each include bisphenol A carbonate repeating units and poly(dimethylsiloxane) repeating units.

[0087] Polycarbonate compositions can be prepared by various methods known in the art. For example, powdered polycarbonate homopolymers, poly(carbonate-siloxane) and other optional components are first optionally blended with any filler in a high-speed mixer or by manual mixing. The blend is then fed to the throat of a twin-screw extruder through a hopper. Alternatively, at least one component can be fed directly to the extruder by passing it through a side stuffer at the throat and / or downstream, or by mixing it into a masterbatch with the desired polymer and feeding it to the extruder and incorporating it into the composition. The extruder is usually operated at a temperature higher than that necessary to cause the composition to flow. The extrudate can be immediately quenched and granulated in a water bath. As required, the pellets so prepared can be a quarter inch long or less. Such pellets can be used for subsequent molding, shaping, or forming.

[0088] Also provided are molded, formed, cast, or molded articles comprising polycarbonate compositions. The polycarbonate compositions can be molded into useful molded articles by a variety of methods, such as injection molding, extrusion, rotational molding, blow molding, and thermoforming. The articles can be molded articles, thermoformed articles, extruded films, extruded sheets, honeycomb structures, one or more layers of multilayer articles, substrates for coating articles, and substrates for metallized articles. Exemplary articles can include computer and business machine housings (such as housings for monitors, handheld electronic devices (such as housings for mobile phones)), electrical connectors, and parts of light fixtures, ornaments, household appliances, roofs, greenhouses, sunrooms, swimming pool fences, electronic equipment packaging and signs, etc. In addition, the polycarbonate compositions can be used in such applications as automotive panels and decorations.Exemplary but non-limiting examples of suitable articles are: exterior and interior parts for aircraft, automobiles, trucks, military vehicles (including automobiles, aircraft and marine vehicles), scooters and motorcycles, including panels, quarter panels, rocker panels, trim, fenders, doors, deck-lids, trunk lids, hoods, bonnets, roofs, bumpers, instrument panels, grilles, mirror housings, pillar trim, cladding, body side moldings, wheel covers, hubcaps, door handles, spoilers, window frames, headlight bezels, headlights, taillights, taillight housings, taillight bezels, license plate housings, roof racks and running boards; enclosures, housings, panels, and parts for outdoor vehicles and devices; enclosures for electrical and telecommunications devices; outdoor furniture; aircraft parts; boat and marine equipment, including trim, enclosures, and housings; outboard motor housings; test Depth gauge housings; personal watercraft; jet skis; pools; spas; hot tubs; steps; step coverings; architectural and construction applications such as glass, roofing, windows, flooring, decorative window furniture or treatments; treated glass covers for pictures, paintings, posters and similar display items; wall panels and doors; countertops; protected graphics; outdoor and indoor signs; housings, cases, panels and parts for automated teller machines (ATMs); computers; desktop computers; portable computers; laptop computers; handheld computer housings; displays; printers ; keyboards; fax machines; copiers; telephones; telephone frames; mobile phones; radio transmitters; radio receivers; enclosures, casings, panels, and parts for lawn and garden tractors, mowers, and tools (including lawn and garden tools); window and door trim; sporting equipment and toys; casings, casings, panels, and parts for snowmobiles; recreational vehicle panels and parts; playground equipment; shoelaces; articles made of plastic-wood combinations; golf course markings; utility pit covers; lamps; lighting fixtures; network interface device casings; transformer casings; air conditioner casings; cladding or Seats; coverings or seats for trains, subways, or buses; instrument housings; antenna housings; coverings for satellite dishes; coated helmets and personal protective equipment; coated synthetic or natural textiles; coated painted articles; coated dyed articles; coated fluorescent articles; coated foam articles; medical device housings; battery housings, including battery housings for electric vehicles, electric bicycles, and household and industrial electronics; components for charging equipment for electric vehicles, including wall box housings, connectors, etc.; wireless charging equipment components; protective covers for electronic devices; kitchen appliance components; and similar applications.

[0089] The compositions of the present invention can be particularly useful for articles for consumer electronic applications. For example, the article can be a component of a consumer electronic device, such as a game console, a game controller, a portable game device, a mobile phone, a television, a personal computer, a tablet computer, a laptop computer, a personal digital assistant, a portable media player, a digital camera, a portable music player, an appliance, a power tool, a robot, a toy, a greeting card, a home entertainment system, a speaker, or a sound bar. In one aspect, the article can be an electronic housing for an adapter, a mobile phone, a smart phone, a GPS device, a laptop computer, a tablet computer, an e-reader, a copier, or a solar device.

[0090] In one aspect, the article can be a laser welded article. For example, the parts or articles as described above can be assembled into articles by laser welding. For example, a method of welding a first article comprising the above-mentioned composition to a second thermoplastic article may include physically contacting at least a portion of the surface of the first article with at least a portion of the surface of the second thermoplastic article, applying laser radiation to the first article, wherein the radiation passes through the first article and the radiation is absorbed by the second article and generates sufficient heat to weld the first article to the second article. The second thermoplastic article may include a variety of thermoplastic polymer compositions that exhibit laser absorption by means known to those skilled in the art, including the use of additives and / or colorants, such as but not limited to carbon black. Exemplary polymer compositions can include, but are not limited to, olefin polymers, including polyethylene and copolymers and terpolymers thereof, polybutylene and copolymers and terpolymers thereof, polypropylene and copolymers and terpolymers thereof; α-olefin polymers, including linear or substantially linear interpolymers of ethylene and at least one α-olefin and random poly(α-olefins); rubber block copolymers; polyamides; polyimides; polyesters, such as poly(arylates), poly(ethylene terephthalate), and poly(butylene terephthalate); vinyl polymers such as polyvinyl chloride and polyvinyl esters such as polyvinyl acetate; acrylic homopolymers, copolymers, and terpolymers; epoxy resins; polycarbonates, polyester-polycarbonates; polystyrenes; poly(arylene ethers), including poly(phenylene ethers); polyurethanes; phenoxy resins; polysulfones; polyethers; acetal resins; polyoxyethylenes; and combinations thereof. More specifically, the polymer is selected from the group consisting of polyethylene, ethylene copolymers, polypropylene, propylene copolymers, polyesters, polycarbonates, polyester-polycarbonates, polyamides, poly(arylene ethers), and combinations thereof. In a specific embodiment, the second article comprises an olefinic polymer, a polyamide, a polyimide, a polystyrene, a polyarylene ether, a polyurethane, a phenoxy resin, a polysulfone, a polyether, an acetal resin, a polyester, a vinyl polymer, an acrylic, an epoxy resin, a polycarbonate, a polyester-polycarbonate, a styrene-acrylonitrile copolymer, or a combination thereof. More specifically, the second article may comprise a polycarbonate homopolymer or copolymer, a polyester homopolymer or copolymer, for example, a poly(carbonate-ester), and combinations thereof. Also disclosed is a laser welded article comprising the thermoplastic composition of the present disclosure in a first component, the first component being laser welded to a second component comprising a second thermoplastic composition as described above.

[0091] The present disclosure is further illustrated by the following non-limiting examples.

[0092] Example

[0093] The materials used in the following examples are shown in Table 1.

[0094] Table 1

[0095]

[0096]

[0097] The components of the composition were mixed and extruded. Moulded parts for physical testing were prepared by injection moulding. The test methods are described in Table 2 below and in the following paragraphs.

[0098] Table 2

[0099]

[0100] The flammability test is conducted in accordance with the procedures of Underwriter's Laboratory Bulletin 94 entitled "Tests for Flammability of Plastic Materials for Parts in Devices and Appliances" (ISBN 0-7629-0082-2), Fifth Edition, dated October 29, 1996, incorporating revisions up to and including December 12, 2003. Several ratings can be applied depending on the burning rate, extinguishing time, ability to resist dripping, and whether the drippings burn. According to the procedure, the materials can be classified as UL94 HB, V0, V1, V2, 5VA or 5VB. The test samples are aged at 23°C, 50% RH for more than 2 days or at 70°C for 168 hours before testing. Specifically, in the UL 94 20mm vertical burning flame test, a set of five burning rods are tested. For each rod, a flame is applied to the rod, then removed, and the time required for the rod to self-extinguish (first burnout time, t1) is recorded. The flame is then reapplied and removed, and the time required for the rod to self-extinguish (second burnout time, t2) and the flame afterglow time (afterglow time, t3) are recorded. To achieve a rating of V-0, the burnout times t1 and t2 of each individual sample must be less than or equal to 10 seconds; and the total burnout time of all five samples (t1 plus t2 for all five samples) must be less than or equal to 50 seconds; and the second burnout time plus the afterglow time (t2+t3) of each individual sample must be less than or equal to 30 seconds; and no sample may burn or glow up to the holding fixture; and the cotton indicator may not be ignited by burning particles or drippings. To achieve a V-1 rating, the burnout time t1 and t2 of each individual sample must be less than or equal to 30 seconds; and the total burnout time of all five samples (t1 plus t2 of all five samples) must be less than or equal to 250 seconds; and the second burnout time plus the afterglow time (t2+t3) of each individual sample must be less than or equal to 60 seconds; and no sample can burn or glow to the holding fixture; and the cotton indicator cannot be ignited by burning particles or drippings. To achieve a V-2 rating, the burnout time t1 and t2 of each individual sample must be less than or equal to 30 seconds; and the total burnout time of all five samples (t1 plus t2 of all five samples) must be less than or equal to 250 seconds; and the second burnout time plus the afterglow time (t2+t3) of each individual sample must be less than or equal to 60 seconds; and no sample can burn or glow to the holding fixture; but the cotton indicator can be ignited by burning particles or drippings.

[0101] Environmental stress crack resistance (ESCR) describes the accelerated failure of a polymeric material due to a combination of environment, temperature and stress. Failure depends primarily on the material properties, chemical properties, exposure conditions and the magnitude of the stress. ISO tensile bars are clamped to a semicircular fixture to apply a constant strain of 1.0%. The bars are then exposed to the chemicals at 23°C for a predetermined period of time. After cleaning, tensile properties are measured at 50 mm / min on standard ASTM tensile test bars at room temperature according to ASTM D638.

[0102] Examples 1-12

[0103] Table 3 shows the composition and properties of the compositions according to Examples 1-12. As can be seen in Table 3, increasing the content of PC-Si having a siloxane content in the range of 30-60% can reduce the observed MVR of the final composition. Comparing the compositions according to Examples 1, 2, 5, and 8, it can be further seen that increasing the content of PC-Si having a siloxane content in the range of 30-60% can also adversely affect the color of the resulting composition. The inventors unexpectedly discovered that adding a second PC-Si having a siloxane content of less than 10% can improve the color. Exposing ASTM tensile bars to chemicals while under strain for a fixed amount of time and then performing standard tensile testing showed that adding PC-Si with a higher Si content can further improve the chemical resistance of the composition. Thus, a composition having a desired balance of color, MVR, and chemical resistance is provided.

[0104] Table 3

[0105]

[0106]

[0107] * indicates comparative example; "x" indicates sample failure

[0108] Thus, the inventors have discovered that blends of specific polycarbonate-siloxane copolymers can provide fine-tuning of the properties of the resulting composition, particularly with respect to color and chemical resistance. As a further advantageous feature, the desired flow (i.e., MVR) can be retained. Thus, the compositions of the present disclosure provide significant improvements

[0109] The present disclosure further encompasses the following aspects.

[0110] Aspect 1: A polycarbonate composition comprising: 20 to 85 weight percent of bisphenol A homopolycarbonate; 10 to 55 weight percent of a first polycarbonate-siloxane copolymer, the first polycarbonate-siloxane copolymer having a siloxane content of 4 to 10 weight percent based on the total weight of the first polycarbonate-siloxane copolymer; and 10 to 25 weight percent of a second polycarbonate-siloxane copolymer, the second polycarbonate-siloxane copolymer having a siloxane content of greater than 30 to 70 weight percent based on the total weight of the second polycarbonate-siloxane copolymer; wherein, when the composition has a total siloxane content of 2 to 7.5%, the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer are present in a weight ratio of less than 2; and when the composition has a total siloxane content of greater than 7.5 to 15%, the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer are present in a weight ratio of 2 to 5.

[0111] Aspect 2: The polycarbonate composition according to aspect 1, wherein the bisphenol A homopolycarbonate has a weight average molecular weight of 18,000 to 40,000 g / mole, or 20,000 to 40,000 g / mole, or 28,000 to 38,000 g / mole as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards.

[0112] Aspect 3: A polycarbonate composition according to Aspect 1 or 2, wherein the first polycarbonate-siloxane copolymer has a siloxane content of 4 to less than 10 weight percent, or 5 to 8 weight percent, based on the total weight of the first polycarbonate-siloxane copolymer; and the first polycarbonate-siloxane copolymer is present in an amount of 15 to 45 weight percent based on the total weight of the composition.

[0113] Aspect 4: The polycarbonate composition according to any one of aspects 1 to 3, wherein the second polycarbonate-siloxane copolymer has a siloxane content of 35 to 65 weight percent based on the total weight of the second polycarbonate-siloxane copolymer.

[0114] Aspect 5: The polycarbonate composition according to any one of aspects 1 to 4, wherein the second polycarbonate-siloxane copolymer is present in the composition in an amount of greater than 15 to 25 weight percent, or 17 to 25 weight percent, based on the total weight of the composition.

[0115] Aspect 6: The polycarbonate composition according to any one of aspects 1 to 5, wherein the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer each comprise bisphenol A carbonate repeating units and poly(dimethylsiloxane) repeating units.

[0116] Aspect 7: A polycarbonate composition according to any one of Aspects 1 to 6, wherein the second polycarbonate-siloxane copolymer has a weight average molecular weight of 21,000 g / mol to 50,000 g / mol, or 25,000 g / mol to 45,000 g / mol, or 30,000 g / mol to 45,000 g / mol, or 32,000 g / mol to 43,000 g / mol, or 35,000 g / mol to 40,000 g / mol as measured by gel permeation chromatography using a cross-linked styrene-divinylbenzene column at a sample concentration of 1 mg / ml and as calibrated using bisphenol A polycarbonate standards.

[0117] Aspect 8: The polycarbonate composition according to any one of aspects 1 to 7, wherein the polycarbonate composition further comprises 0.1 to 10 weight percent of an additive composition based on the total weight of the polycarbonate composition, preferably, wherein the additive composition comprises an anti-drip agent, a flame retardant, a colorant composition, or a combination thereof; more preferably, wherein the additive composition comprises: 0.05 to 1 weight percent of an inorganic flame retardant, preferably comprising C 1-16 Sulfonate salts, more preferably comprising potassium perfluorobutanesulfonate (Rimar salt), potassium perfluorooctanesulfonate, tetraethylammonium perfluorohexanesulfonate, and potassium diphenylsulfonesulfonate, or combinations thereof; and optionally 0.01 to 1 weight percent of an anti-drip additive.

[0118] Aspect 9: The polycarbonate composition according to any one of aspects 1 to 8, comprising 50 to 60 weight percent of bisphenol A homopolycarbonate; 25 to 35 weight percent of the first polycarbonate-siloxane copolymer; and 15 to 20 weight percent of the second polycarbonate-siloxane copolymer.

[0119] Aspect 10: A polycarbonate composition according to Aspect 9, wherein the bisphenol A homopolycarbonate has a weight average molecular weight of 28,000 to 38,000 g / mole as determined by gel permeation chromatography relative to a linear bisphenol A polycarbonate standard; the first polycarbonate-siloxane copolymer has a siloxane content of 4 to 8 weight percent based on the total weight of the first polycarbonate-siloxane copolymer; the second polycarbonate-siloxane copolymer has a siloxane content of 35 to 65 weight percent based on the total weight of the second polycarbonate-siloxane copolymer; the composition contains less than 1 weight percent of a polycarbonate-siloxane copolymer having a siloxane content of greater than 10 to less than 30 weight percent; and the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer each contain bisphenol A carbonate repeating units and poly(dimethylsiloxane) repeating units.

[0120] Aspect 11: A polycarbonate composition according to any one of Aspects 1 to 10, wherein a molded sample of the composition exhibits an L* value of less than or equal to 10 measured by the CIE Lab method, using a 10 degree observer, a D65 light source, removing the specular reflection component, and measuring in reflection mode, and using a sample having a thickness of 3.2 mm.

[0121] Aspect 12: The polycarbonate composition of any of Aspects 1 to 11, wherein after exposure to a sunscreen or insect repellent, a molded sample of the composition exhibits a tensile strain at break that is at least 50% of the tensile strain at break of an unexposed reference sample.

[0122] Aspect 13: The polycarbonate composition according to any one of Aspects 1 to 12, wherein a molded sample of the composition exhibits a UL-94 flame rating of V0 or V1 at a thickness of 1.5 mm or less, preferably a UL-94 flame rating of V0 or V1 at a thickness of 1.2 mm or less.

[0123] Aspect 14: A method of making a polycarbonate composition according to any of aspects 1 to 13, the method comprising melt mixing components of the composition, and optionally, extruding the composition.

[0124] Aspect 15: An article comprising the polycarbonate composition according to any one of aspects 1 to 13.

[0125] Alternatively, the compositions, methods and articles may comprise, consist of, or consist essentially of any suitable material, step or component disclosed herein. The compositions, methods and articles may additionally or alternatively be formulated so as to be free of or essentially free of any material (or species), step, or component that is otherwise not necessary to achieve the function or purpose of the compositions, methods and articles.

[0126] All ranges disclosed herein include endpoints, and endpoints can be combined independently of each other. "Combination" includes blends, mixtures, alloys, reaction products, etc. The terms "first", "second", etc. do not represent any order, quantity or importance, but are used to distinguish one element from another element. Unless otherwise specified herein or clearly contradictory to the context, the terms "one (a)" and "an" and "the" do not represent the limitation of quantity, but are interpreted as covering the singular and plural. Unless otherwise clearly stated, "or" means "and / or". Throughout the specification, mentioning "an aspect" means that the specific elements described in conjunction with the aspect are included in at least one aspect described herein, and may or may not be present in other aspects. The term "their combination" as used in this article includes one or more listed elements, and is open, allowing one or more unnamed similar elements to exist. In addition, it should be understood that the described elements can be combined in any suitable manner in various aspects.

[0127] Unless specified to the contrary herein, all test standards are the latest standards in effect as of the filing date of this application, or, if priority is claimed, as of the filing date of the earliest priority application in which the test standards appear.

[0128] Unless otherwise defined, the technical and scientific terms used herein have the same meanings as those generally understood by those of ordinary skill in the art to which the application belongs. All cited patents, patent applications, and other references are incorporated herein by reference in their entirety. However, if a term in the present application contradicts or conflicts with a term in an incorporated reference, the term from the present application takes precedence over the conflicting term from the incorporated reference.

[0129] Compounds are described using standard nomenclature. For example, any position not substituted by any indicator group is understood to have its valency filled by a bond or hydrogen atom as indicated. A dash ("-") not between two letters or symbols is used to indicate the point of attachment of a substituent. For example, -CHO is connected through the carbon of a carbonyl group.

[0130] As used in this article, the term "alkyl", whether used alone or as a prefix, suffix or part of another term, refers to a residue containing only carbon and hydrogen. The residue can be aliphatic or aromatic, straight chain, cyclic, bicyclic, branched, saturated or unsaturated. It can also contain a combination of aliphatic, aromatic, straight chain, cyclic, bicyclic, branched, saturated and unsaturated hydrocarbon parts. However, when the alkyl residue is described as substituted, it can optionally contain heteroatoms on and above the carbon and hydrogen members of the substituent residue. Therefore, when specifically described as substituted, the alkyl residue can also include one or more carbonyls, amino, hydroxyl, etc., or it can include heteroatoms in the main chain of the alkyl residue. The term "alkyl" refers to a branched or straight chain, saturated aliphatic hydrocarbon group, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, n-pentyl, sec-pentyl and n-hexyl and sec-hexyl. "Alkenyl" refers to a straight or branched monovalent hydrocarbon radical having at least one carbon-carbon double bond (e.g., vinyl (-HC=CH2)). "Alkoxy" refers to an alkyl radical attached via an oxygen (i.e., alkyl-O-), such as methoxy, ethoxy, and sec-butoxy. "Alkylene" refers to a straight or branched, saturated, divalent aliphatic hydrocarbon radical (e.g., methylene (-CH2-) or propylene (-(CH2)3-)). "Cycloalkylene" refers to a divalent cyclic alkylene radical, -C n H 2n-x , wherein x is the number of hydrogens replaced by cyclization. "Cycloalkenyl" refers to a monovalent group having one or more rings and one or more carbon-carbon double bonds in the ring, wherein all ring members are carbon atoms (e.g., cyclopentyl and cyclohexyl). "Aryl" refers to an aromatic hydrocarbon group containing a specific number of carbon atoms, such as phenyl, cycloheptatrienone, indanyl, or naphthyl. "Arylene" refers to a divalent aryl group. "Alkylidenearylene" refers to an arylidene group substituted by an alkyl group. "Arylalkylene" refers to an alkylene group substituted by an aryl group (e.g., benzyl). The prefix "halo" refers to a group or compound comprising one or more of fluorine, chlorine, bromine, or iodine substituents. There may be a combination of different halogen atoms (e.g., bromine and fluorine) or only chlorine atoms. The prefix "hetero" refers to a compound or group comprising at least one ring member of a heteroatom (e.g., 1, 2, or 3 heteroatoms), wherein the heteroatoms are each independently N, O, S, Si, or P. "Substituted" means that the compound or group is substituted with at least one (e.g., 1, 2, 3, or 4) substituent, each of which is independently C 1-9 Alkoxy, C 1-9 Haloalkoxy, nitro (-NO2), cyano (-CN), C 1-6 Alkylsulfonyl (-S(=O)2-alkyl), C 6-12Arylsulfonyl (-S(=O)2-aryl), thiol (-SH), thiocyanate (-SCN), tosyl (CH3C6H4SO2-), C 3-12 Cycloalkyl, C 2-12 Alkenyl, C 5-12 Cycloalkenyl, C 6-12 Aryl, C 7-13 Arylalkylene, C 4-12 Heterocycloalkyl, and C 3-12 Heteroaryl, other than hydrogen, provided that the normal valence of the substituted atom is not exceeded. The number of carbon atoms indicated in the group does not include any substituents. For example, -CH2CH2CN is a C2 alkyl substituted with a nitrile.

[0131] Although specific embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents that are not currently foreseeable or may not be foreseeable may occur to the applicant or other persons skilled in the art. Therefore, the appended claims as filed and as they may be amended are intended to cover all such alternatives, modifications, variations, improvements, and substantial equivalents.

Claims

1. A polycarbonate composition comprising: 20 to 85 weight percent of bisphenol A homopolycarbonate; 10 to 55 weight percent of a first polycarbonate-siloxane copolymer, the first polycarbonate-siloxane copolymer having a siloxane content of 4 to 10 weight percent based on the total weight of the first polycarbonate-siloxane copolymer; and 10 to 25 weight percent of a second polycarbonate-siloxane copolymer, the second polycarbonate-siloxane copolymer having a siloxane content of greater than 30 to 70 weight percent based on the total weight of the second polycarbonate-siloxane copolymer; in When the composition has a total siloxane content of 2 to 7.5%, the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer are present in a weight ratio of less than 2; and When the composition has a total siloxane content of greater than 7.5 to 15%, the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer are present in a weight ratio of 2 to 5.

2. The polycarbonate composition according to claim 1, wherein The bisphenol A homopolycarbonate has a weight average molecular weight of 18,000 to 40,000 g / mole, or 20,000 to 40,000 g / mole, or 28,000 to 38,000 g / mole as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards.

3. The polycarbonate composition according to claim 1 or 2, wherein The first polycarbonate-siloxane copolymer has a siloxane content of 4 to less than 10 weight percent, or 5 to 8 weight percent, based on the total weight of the first polycarbonate-siloxane copolymer; and The first polycarbonate-siloxane copolymer is present in an amount of 15 to 45 weight percent based on the total weight of the composition.

4. The polycarbonate composition according to any one of claims 1 to 3, wherein The second polycarbonate-siloxane copolymer has a siloxane content of 35 to 65 weight percent based on the total weight of the second polycarbonate-siloxane copolymer.

5. The polycarbonate composition according to any one of claims 1 to 4, wherein The second polycarbonate-siloxane copolymer is present in the composition in an amount of greater than 15 to 25 weight percent, or 17 to 25 weight percent, based on the total weight of the composition.

6. The polycarbonate composition according to any one of claims 1 to 5, wherein The first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer each comprise bisphenol A carbonate repeating units and poly(dimethylsiloxane) repeating units.

7. The polycarbonate composition according to any one of claims 1 to 6, wherein The second polycarbonate-siloxane copolymer has a weight average molecular weight of 21,000 to 50,000 g / mol, or 25,000 to 45,000 g / mol, or 30,000 to 45,000 g / mol, or 32,000 to 43,000 g / mol, or 35,000 to 40,000 g / mol, as determined by gel permeation chromatography using a cross-linked styrene-divinylbenzene column at a sample concentration of 1 mg / ml and calibrated using a bisphenol A polycarbonate standard.

8. The polycarbonate composition according to any one of claims 1 to 7, wherein The polycarbonate composition further comprises 0.1 to 10 weight percent of an additive composition based on the total weight of the polycarbonate composition. Preferably, wherein the additive composition comprises an anti-drip agent, a flame retardant, a colorant composition, or a combination thereof, More preferably, the additive composition comprises: 0.05 to 1 weight percent of an inorganic flame retardant, preferably comprising C 1-16 Sulfonates, more preferably comprising potassium perfluorobutanesulfonate (Rimar salt), potassium perfluorooctanesulfonate, tetraethylammonium perfluorohexanesulfonate, and potassium diphenylsulfonesulfonate, or combinations thereof; and Optionally 0.01 to 1 weight percent of an anti-drip additive.

9. The polycarbonate composition according to any one of claims 1 to 8, comprising 50 to 60 weight percent of the bisphenol A homopolycarbonate; 25 to 35 weight percent of the first polycarbonate-siloxane copolymer; and 15 to 20 weight percent of the second polycarbonate-siloxane copolymer.

10. The polycarbonate composition according to claim 9, wherein The bisphenol A homopolycarbonate has a weight average molecular weight of 28,000 to 38,000 g / mole as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards; The first polycarbonate-siloxane copolymer has a siloxane content of 4 to 8 weight percent based on the total weight of the first polycarbonate-siloxane copolymer; The second polycarbonate-siloxane copolymer has a siloxane content of 35 to 65 weight percent based on the total weight of the second polycarbonate-siloxane copolymer; The composition comprises less than 1 weight percent of a polycarbonate-siloxane copolymer having a siloxane content of greater than 10 to less than 30 weight percent; and The first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer each comprise bisphenol A carbonate repeating units and poly(dimethylsiloxane) repeating units.

11. The polycarbonate composition according to any one of claims 1 to 10, wherein A molded sample of the composition exhibits an L* value less than or equal to 10 measured by the CIE Lab method using a 10 degree observer, a D65 light source, removing the specular component, and measuring in reflection mode, and using a sample having a thickness of 3.2 mm.

12. The polycarbonate composition according to any one of claims 1 to 11, wherein After exposure to the sunscreen or insect repellent, a molded sample of the composition exhibits a tensile strain at break that is at least 50% of the tensile strain at break of an unexposed reference sample.

13. The polycarbonate composition according to any one of claims 1 to 12, wherein A molded sample of the composition exhibits a UL-94 flame rating of V0 or V1 at a thickness of 1.5 mm or less, preferably a UL-94 flame rating of V0 or V1 at a thickness of 1.2 mm or less.

14. A method of making the polycarbonate composition of any one of claims 1 to 13, the method comprising melt mixing the components of the composition, and optionally, extruding the composition.

15. An article comprising the polycarbonate composition of any one of claims 1 to 13.

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