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

Abstract

A polycarbonate composition includes 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. The composition can provide a combination of desirable properties, including good flame performance, chemical resistance, and aesthetic properties.

Description

[0001] Related applications

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

[0003] This disclosure relates to polycarbonate compositions, articles formed from the compositions, and methods of manufacturing them. 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 resistance. 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 exhibit good mechanical properties and low-temperature impact resistance. However, blends of polycarbonate homopolymers with such polycarbonate-polysiloxane copolymers can result in poor aesthetics of molded parts. Aesthetic defects can include excessive haze, limited color space capability, pearlescent finish, or other molding-related surface defects such as streaks and runouts. Previous attempts to improve aesthetics may compromise other desired properties, such as low-temperature impact resistance, flame retardancy, and chemical resistance.

[0006] Therefore, there remains a need in the field for polycarbonate compositions that can achieve a balance of aesthetics, flame retardancy, and chemical resistance. Summary of the Invention

[0007] The polycarbonate composition comprises 20 to 85 weight percent of bisphenol A homopolymer polycarbonate; 10 to 55 weight percent of a first polycarbonate-siloxane copolymer, based on the total weight of the first polycarbonate-siloxane copolymer, the first polycarbonate-siloxane copolymer having a siloxane content of 4 to 10 weight percent; and 10 to 25 weight percent of a second polycarbonate-siloxane copolymer, based on the total weight of the second polycarbonate-siloxane copolymer, the second polycarbonate-siloxane copolymer having a siloxane content of greater than 30 to 70 weight percent; 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 for preparing a polycarbonate composition, which includes melt-blending the components of the composition and, optionally, extruding the composition.

[0009] On the other hand, there are articles containing polycarbonate compositions.

[0010] The above and other features are illustrated by the following detailed description. Detailed Implementation

[0011] The inventors have discovered that polycarbonate compositions comprising a specific amount of bisphenol A homopolymer, a first polycarbonate-siloxane copolymer having a siloxane content of 4 to 10% by weight 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% by weight based on the total weight of the second polycarbonate-siloxane copolymer, can provide a combination of desired properties. For example, compositions according to this disclosure have been found to 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 homopolymer polycarbonate. The bisphenol A homopolymer polycarbonate has carbonate units with 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, such as monocyclic phenols such as phenol, p-cyanophenol, and C... 1-22Alkyl-substituted phenols such as p-cumylphenol, resorcinol monobenzoic acid, esters, 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 branching agents during polymerization, such as trimellitic acid, trimellitic anhydride, trimellityl chloride, tris(p-hydroxyphenyl)ethane, indigo-bisphenol, pyromellitic acid TC (1,3,5-tris((p-hydroxyphenyl)isopropyl)benzene), pyromellitic acid PA (4(4(1,1-bis(p-hydroxyphenyl)-ethyl)α,α-dimethylbenzyl)phenol), 4-chloroformyl phthalic anhydride, pyromellitic acid, and benzophenone tetracarboxylic acid. The branching agent can be added at a level of 0.05 to 4.0 wt%, for example, 0.05 to 2.0 wt%. Compositions comprising linear polycarbonate and branched polycarbonate can be used.

[0015] The bisphenol A polycarbonate homopolymer may be a linear bisphenol A polycarbonate homopolymer, optionally end-capped with phenol or p-cumylphenol, and has a weight-average molecular weight of 10,000 to 100,000 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 determined by gel permeation chromatography (GPC) using a cross-linked styrene-divinylbenzene column and calibrated relative to a bisphenol A polycarbonate reference. GPC samples are prepared at a concentration of 1 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 comprise 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 different. 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 total weight of the composition, bisphenol A homopolycarbonate may be present in the composition in an amount of 20 to 85 weight percent. Within this range, bisphenol A homopolycarbonate may be present in amounts such as 25 to 75 weight percent, or 30 to 70 weight percent, or 30 to 65 weight percent, or 35 to 65 weight percent, or 40 to 65 weight percent, or 45 to 65 weight percent, or 40 to 60 weight percent, or 40 to 55 weight percent, or 30 to 55 weight percent, or 30 to 50 weight percent, or 40 to 50 weight percent, each based on the total weight of the composition.

[0018] In addition to bisphenol A homopolymer polycarbonate, the polycarbonate composition also includes a first polycarbonate-siloxane copolymer and a second polycarbonate-siloxane copolymer. The polycarbonate-siloxane copolymer is also referred to as polycarbonate-siloxane. Both the first and second polycarbonate-siloxane copolymers contain repeating carbonate units and siloxane units. The carbonate units can be derived from dihydroxy aromatic compounds such as bisphenol of formula (2) or diphenol of formula (3):

[0019]

[0020] In equation (2), R a and R b Each is C independently 1-12 Alkyl, C 1-12 alkenyl, C 3-8 cycloalkyl, or C 1-12 The alkoxy groups, p and q, are each independently 0 to 4, and X a It is a single bond, -O-, -S-, -S(O)-, -S(O)2-, -C(O)-, and the formula -C(R) c (R) d )- of C 1-11 Alkyl groups, wherein R c and R d Each is independently either hydrogen or C. 1-10 Alkyl groups, or those with the formula -C(=R) e )- groups, wherein R e It is divalent C 1-10 Hydrocarbon group; and in formula (3), each R h Independent of 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 respect, in equations (2) and (3), Ra and R b Each is C independently 1-3 Alkyl or C 1-3 The alkoxy group, p, and q are each independently 0 or 1, and X a It is a single bond, -O-, -S(O)-, -S(O)2-, -C(O)-, and the formula -C(R) c (R) d )- of C 1-11 Alkyl groups, wherein R c and R d Each is independently either hydrogen or C. 1-10 Alkyl, each R h Independently, it is bromine, C 1-3 Alkyl, halogen-substituted C 1-3 Alkyl group, and n is 0 to 1.

[0022] In one respect, in equations (2) and (3), R a and R b Each is C independently 1-3 Alkyl groups, p and q are each independently 0 or 1, and X a It is a single bond, -O-, -S(O)-, -S(O)2-, -C(O)-, and the formula -C(R) c (R) d )- of C 1-11 Alkyl groups, wherein R c and R d Each is independently either hydrogen or C. 1-10 Alkyl, each R h Independently, it is bromine, C 1-3 Alkyl, halogen-substituted C 1-3 Alkyl group, and n is 0 to 1.

[0023] In one respect, in equation (2), p and q are each independently 0, and X a It is a single bond, -O-, -S(O)-, -S(O)2-, -C(O)-, and the formula -C(R) c (R) d )- of C 1-11 Alkyl groups, wherein R c and R d Each is independently either hydrogen or C. 1-10 alkyl.

[0024] In one respect, in equation (2), p and q are each independently 0, and X a It is the formula -C(R) c (R) d )- of C 1-11 Alkyl groups, wherein R c and R dEach is independently either hydrogen or C. 1-10 alkyl.

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

[0026] Examples of bisphenol compounds (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)isocyanate. 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) ether 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 (spirodiindane bisphenol), 3,3-bis(4-hydroxyphenyl)phthalimide, 2,6-dihydroxydibenzo-p-dioxin, 2,6-dihydroxythiaanthracene, 2,7-dihydroxyphenoxathin, 2,7-dihydroxy-9,10-dimethylphenazine, 3,6-dihydroxydibenzofuran, 3,6-dihydroxydibenzothiophene, and 2,7-dihydroxycarbazole. Combinations containing different bisphenol compounds can be used.

[0027] Examples of diphenol compounds (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-tetratert-butylhydroquinone, 2,3,5,6-tetrafluorohydroquinone, 2,3,5,6-tetrabromohydroquinone, etc. Combinations containing different diphenol compounds may be used.

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

[0029] The siloxane unit (also known as a polysiloxane block) is optionally of formula (4):

[0030]

[0031] Each R is independently C 1-13 Monovalent organic groups. For example, R can be C. 1-13 Alkyl, C 1-13 Alkoxy, C 2-13 alkenyl, C 2-13 alkenyloxy group, C 3-6 cycloalkyl, C 3-6 Cycloalkoxy, C 6-14 Aryl, C 6-10 aryloxy group, C 7-13 Arylalkylene, C 7-13 Arylalkyleneoxy, C 7-13 alkylarylene, or C 7-13 Alkylaryloxy groups. These groups can be fully or partially halogenated with fluorine, chlorine, bromine, or iodine, or combinations thereof. In one aspect, when a transparent poly(carbonate-siloxane) is desired, R is not halogenated. Combinations of the aforementioned R groups can be used in the same copolymer.

[0032] In one respect, R is C 1-3 Alkyl, C 1-3 Alkoxy, C 3-6 cycloalkyl, C 3-6 Cycloalkoxy, C 6-14 Aryl, C 6-10Aryloxy, C7 arylalkylene, C7 arylalkyleneoxy, C7 alkylarylene, or C7 alkylaryloxy. In one aspect, R is methyl, trifluoromethyl, or phenyl, preferably methyl.

[0033] The value of E in equation (4) can vary widely depending on the type and relative amount of each component in the polycarbonate composition, the desired properties of the composition, etc. 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 respect, the siloxane unit is of formula (5).

[0035]

[0036] Wherein, E is as defined above in the context of equation (4); each R may be the same or different, and is as defined above in the context of equation (4); and Ar may be the same or different, and is a substituted or unsubstituted C. 6-30 The aryl group, wherein the bond is directly attached to the aromatic moiety. The Ar group in formula (5) can be derived from C. 6-30 Dihydroxyaryl compounds, such as the dihydroxy compounds of formula (3). Exemplary dihydroxyaryl 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 respect, the siloxane unit is of formula (6).

[0040]

[0041] Where R and E are as described above in the context of equation (4), and each R 5 Independently is divalent C1-30 Organic groups, wherein the polymerized polysiloxane unit is a reactive residue of its corresponding dihydroxy compound. In one aspect, the polydiorganosiloxane block is of formula (7):

[0042]

[0043] Where R and E are defined above in the context of equation (4). R in equation (7) 6 It is divalent C 2-8 Aliphatic groups. Each M in formula (7) may be the same or different, and may be halogen, cyano, nitro, C 1-8 Alkyl thio, C 1-8 Alkyl, C 1-8 Alkoxy, C 2-8 alkenyl, C 2-8 alkenyloxy group, C 3-8 cycloalkyl, C 3-8 Cycloalkoxy, C 6-10 Aryl, C 6-10 aryloxy group, C 7-12 Aryl alkyl, C 7-12 Arylalkyleneoxy, C 7-12 alkylarylene, or C 7-12 Alkylaryloxy group, wherein each n is independently 0, 1, 2, 3 or 4.

[0044] In one respect, M is bromine or chlorine, alkyl such as methyl, ethyl, or propyl, alkoxy such as methoxy, ethoxy, or propoxy, or aryl such as phenyl, chlorophenyl, or tolyl; R 6 It is ethylene, propylene, or butylene; and R is C 1-8 Alkyl, haloalkyl such as trifluoropropyl, cyanoalkyl, or aryl such as phenyl, chlorophenyl, or tolyl. In one aspect, R is methyl, or a combination of methyl and trifluoropropyl, or a combination of methyl and phenyl. In another aspect, R is methyl, M is methoxy, n is 1, and R 6 It is divalent C 1-3 Aliphatic groups. 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 using known methods. Polycarbonate-siloxanes can be prepared by introducing phosgene into a mixture of bisphenol and terminally capped polydimethylsiloxane (PDMS) under interfacial reaction conditions. Other known methods may also be used.

[0048] In one aspect, the poly(carbonate-siloxane) comprises a carbonate unit derived from bisphenol A and repeating siloxane units (5a), (5b), (7a), (7b), (7c), or combinations thereof (preferably 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 inventors have unexpectedly discovered that when specific combinations of polycarbonate-siloxane copolymers are used in a composition, the polycarbonate composition can exhibit a combination of desired properties, including good chemical resistance, flame retardancy, and aesthetic properties.

[0050] Based on the total weight of the first polycarbonate-siloxane copolymer, the first polycarbonate-siloxane copolymer may have a siloxane content of 4 to 10 weight percent. Within this range, the first polycarbonate-siloxane copolymer may 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 poly(carbonate-siloxane) refers to the content of siloxane units based on the total weight of the polycarbonate-siloxane copolymer.

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

[0052] The first polycarbonate-siloxane copolymer may 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 crosslinked styrene-divinylbenzene column and calibrated using the bisphenol A polycarbonate standard.

[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. The weight-average molecular weight can be measured by gel permeation chromatography at a sample concentration of 1 mg / mL using a cross-linked styrene-divinylbenzene column, and 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%, for example, 12 to 28 wt%. Preferably, polycarbonate-siloxane having a siloxane content of greater than 10 to less than 30 wt%, for example, 12 to 28 wt%, is excluded from the composition.

[0055] The first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer may be present in the composition in an amount providing 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 may have a total siloxane content of 2 to 7.5 weight percent, and the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer may be present in a weight ratio of less than 2 (i.e., less than 2:1), for example 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 may have a total siloxane content of more than 7.5 to 15 percent by weight, and the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer may be present in a weight ratio of 1.5 to 5 or 2 to 5 (i.e., 2:1 to 5:1), for example 1.5:1 to 5:1, or 2:1 to 4:1, or 2:1 to 3:1.

[0056] Based on the total weight of the composition, the first polycarbonate-siloxane copolymer may be present in the composition in an amount of 10 to 55 weight percent. Within this range, each of the first polycarbonate-siloxane copolymers may 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, based on the total weight of the composition.

[0057] Based on the total weight of the composition, the second polycarbonate-siloxane copolymer may be present in the composition in an amount of 10 to 25 weight percent. Within this range, each of the second polycarbonates may be present in an amount, 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, based on the total weight of the composition.

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

[0059] The polycarbonate composition may optionally further comprise an additive composition containing one or more additives typically incorporated into polymer compositions of this type, provided that the one or more additives are selected to not significantly adversely affect the desired properties of the polycarbonate composition, particularly impact resistance, chemical resistance, and flame retardancy. Additives may 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. Combinations of additives may be used, such as combinations of heat stabilizers, mold release agents, and UV light stabilizers. Generally, additives are used in amounts generally known to be effective. For example, the total amount of additives (other than any impact modifier, filler, or reinforcing agent) may be from 0.01 to 5% by weight, based on the total weight of the polycarbonate composition. In one aspect, the polycarbonate composition contains no more than 5% by weight of processing aids, heat stabilizers, antioxidants, UV absorbers, colorants, or combinations thereof.

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

[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. Di- or polyfunctional aromatic phosphorus compounds are also useful, such as resorcinol tetraphenyl diphosphate (RDP), hydroquinone bis(diphenyl) phosphate and bisphenol A bis(diphenyl) phosphate, as well as their oligomeric and polymeric counterparts.

[0062] Flame retardant compounds containing phosphorus-nitrogen bonds include phosphazenes, chlorophosphazenes, phosphorus esteramides, phosphoramides, phosphonamides, hypophosphonamides, and tris(acridinyl)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, as well as decabromodiphenyl ether, and oligomerized and polymerized halogenated aromatic compounds such as bisphenol A and tetrabromobisphenol A copolycarbonates with carbonate precursors (e.g., phosgene). Metal synergists, such as antimony oxide, can also be used with flame retardants.

[0064] Alternatively, the thermoplastic composition may 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 parts (ppm), less than or equal to 75 ppm, or less than or equal to 50 ppm based on the total parts by weight of the composition.

[0065] Inorganic flame retardants, such as C, can also be used. 1-16 Alkyl sulfonates, such as potassium perfluorobutane sulfonate (Rimar salt), potassium perfluorooctane sulfonate, tetraethylammonium perfluorohexane sulfonate, and potassium diphenyl sulfone sulfonate; 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 may be included in the composition in an amount of 0.01 to 10 weight percent. Within this range, the flame retardant may 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, respectively, based on the total weight of the composition. In one aspect, when the flame retardant comprises an inorganic flame retardant, the flame retardant may be present in an amount of 0.05 to 1 weight percent.

[0067] Heat stabilizer additives may include organic phosphites (e.g., triphenyl phosphite, tri-(2,6-dimethylphenyl) phosphite, tri-(mixed mono- and dinonylphenyl) phosphite, etc.), phosphonates (e.g., dimethylphenyl phosphonate, etc.), phosphates (e.g., trimethyl phosphate, etc.), or combinations thereof. The heat stabilizer may be tris(2,4-di-tert-butylphenyl) phosphate, which is available as IRGAPHOS168. The heat stabilizer is typically used in amounts from 0.01 to 5 wt% based on the total weight of the polymer in the composition.

[0068] Light stabilizers or ultraviolet (UV) absorbing additives, also known as UV stabilizers, can 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 combinations thereof.

[0069] UV absorber additives include hydroxybenzophenone; hydroxybenzotriazole; hydroxybenzotriazine; cyanoacrylate; oxanilide; benzoxazinone; 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 531). 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 ethyl ester (UVINUL3028), 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)-sebate (UVINUL4077H), bis-(1,2,2,6,6-pentamethyl-4-piperidinyl)-sebate + methyl-(1,2,2,6,6-pentamethyl-4-piperidinyl)-sebate (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; nanoscale inorganic materials such as titanium oxide, cerium oxide, and zinc oxide, all having a particle size of less than or equal to 100 nanometers; etc., or combinations thereof. The UV absorber can be used in amounts from 0.01 to 1 part by weight based on 100 parts by weight of polycarbonate and impact modifier. UV absorbers 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 combinations 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 release agents may also be used. There is considerable overlap among these types of materials, which include, for example, phthalates such as dioctyl-4,5-epoxy-hexahydrophthalate; tri-(octyloxycarbonylethyl)isocyanurate; glyceryl tristearate; di- or polyfunctional aromatic phosphates such as resorcinol tetraphenyl phosphate (RDP), hydroquinone bis(diphenyl) phosphate, and bisphenol A bis(diphenyl) phosphate; poly-α-olefins; epoxidized soybean oil; and silicones, including silicone... Oils; esters, such as fatty acid esters such as alkyl stearates, such as methyl stearate, stearyl stearate, pentaerythritol tetrastearate, etc.; methyl stearate combined with hydrophilic and hydrophobic nonionic surfactants comprising polyethylene glycol polymers, polypropylene glycol polymers, poly(ethylene glycol-co-propylene glycol) copolymers, or combinations thereof, such as methyl stearate and polyethylene glycol-polypropylene glycol copolymers in suitable solvents; waxes such as beeswax, lignite wax, paraffin wax, etc.

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

[0072] In one aspect, polycarbonate may comprise a colorant composition. Suitable colorants may include, but are not limited to, those known by their color indices, 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, Aminoketone Black, Solvent Black 7, Aniline Black 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 mixtures comprising at least one of the aforementioned colorants. Preferred colorants may include Solvent Red 135, Solvent Yellow 163, Solvent Green 3, and mixtures 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. Among other factors, the specific amount of colorant used can depend on its solubility and extinction coefficient in the polycarbonate composition, and whether it is used in combination with one or more other colorants. Suitable amounts and combinations can be readily determined by those skilled in the art guided by this disclosure. Typical amounts of colorant can be, for example, 0.1 to 1 weight percent based on the total weight of the composition, or, 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 composition providing black color can comprise a green dye and a red dye. In another 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 comprise an additive composition containing 0.05 to 1 weight percent of an inorganic flame retardant, preferably containing C 1-16 Sulfonates, more preferably potassium perfluorobutane sulfonate, potassium perfluorooctane sulfonate, tetraethylammonium perfluorohexane sulfonate, and potassium diphenyl sulfonate, or combinations thereof; and optionally 0.01 to 1% by weight of an anti-dripping 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 homopolymer, and first polycarbonate-siloxane copolymer and second polycarbonate-siloxane copolymer. For example, the composition may minimize or exclude polyester (e.g., polyester may be present in an amount of 1% by weight or less, preferably, wherein polyester is excluded from the composition). The composition may optionally exclude polycarbonates other than bisphenol A homopolymer and polycarbonate-siloxane copolymer, such as polyester-carbonates or bisphenol A copolymers 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 may exclude halogenated flame retardants, such as brominated flame retardants, including brominated polycarbonates (e.g., polycarbonates containing brominated carbonates comprising units derived from 2,2',6,6'-tetrabromo-4,4'-isopropylidene diphenol (TBBPA) and carbonate units derived from at least one dihydroxy aromatic compound not TBBPA), brominated epoxy resins, and combinations thereof. The composition may optionally exclude inorganic flame retardants. The composition may optionally exclude phosphorus-containing flame retardants.

[0077] This composition can advantageously exhibit one or more desired properties. For example, with specific siloxane contents, it has been found that improved chemical resistance can be unexpectedly obtained by combining bisphenol A homopolymer with a first polycarbonate-siloxane and a second polycarbonate-siloxane. These compositions can have balanced properties, including two or more of chemical resistance, flame retardancy, and improved color. Not wanting to be bound by theory, it is believed that by carefully selecting and balancing the first and second polycarbonate-siloxane copolymers used in the composition, including selecting the weight percentage of siloxane units in the polycarbonate-siloxane, unexpected combinations of chemical resistance, flame retardancy, and color can be achieved.

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

[0079] Polycarbonate compositions can further exhibit good flame retardant properties. In measuring flame retardancy, the UL94 standard uses ratings of V0, V1, V2, or HB, where V0 is superior to V1 or V2, and the V0 rating is required for applications with various actual part thicknesses. Using this standard, polycarbonate compositions are molded into articles of a given thickness. The thinner the article, the more difficult it is to achieve a V0 or V1 rating. In one aspect, molded samples of polycarbonate compositions can achieve a UL-94 V0 or V1 rating at a thickness of 1.5 mm or less, preferably at a thickness of 1.2 mm or less.

[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, specular reflection component removed, in reflection mode, and using a sample with a thickness of 3.2 mm.

[0081] The polycarbonate composition can further exhibit good melt viscosity, which facilitates processing. The polycarbonate composition can have a melt volumetric rate (MVR) of 4 to 20 or 7 to 15, greater than or equal to 4, or greater than or equal to 5, as determined according to ISO 1133 at 2.16 kg load and 300 °C for 300 seconds. 3 / 10min)).

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

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

[0084] In one aspect, the polycarbonate composition may have an L* value of less than or equal to 10, a tensile strain at break of at least 50% of the tensile strain at break of an unexposed reference sample after exposure to the sunscreen, 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 this disclosure may comprise 20 to 85 weight percent of bisphenol A homopolymer; 10 to 55 weight percent of 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 10 to 25 weight percent of 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 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. Alternatively, 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. The bisphenol A homopolymer may have a weight-average molecular weight of 18,000 to 40,000 g / mol, or 20,000 to 40,000 g / mol, or 28,000 to 38,000 g / mol, as determined 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% by weight. Based on the total weight of the composition, the first polycarbonate-siloxane copolymer may be present in an amount of 15 to 45% by weight. 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% by weight. Based on the total weight of the composition, the second polycarbonate-siloxane copolymer may be present in the composition in an amount greater than 15 to 25% by weight, or 17 to 25% by weight. The composition may contain less than 5% by weight, or less than 1% by weight, or preferably excludes a polycarbonate-siloxane copolymer having a siloxane content of greater than 10% to less than 30% by weight. The first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer may each contain a bisphenol A carbonate repeating unit and a poly(dimethylsiloxane) repeating unit. The second polycarbonate-siloxane copolymer may 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 determined by gel permeation chromatography using a cross-linked styrene-divinylbenzene column at a sample concentration of 1 mg / mL, and as calibrated using a bisphenol A polycarbonate standard.Based on the total weight of the polycarbonate composition, the polycarbonate composition may further comprise 0.1 to 10 weight percent of an additive composition. Molded samples 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 comprise 50 to 60 weight percent of bisphenol A homopolymer; 25 to 35 weight percent of a first polycarbonate-siloxane copolymer; and 15 to 20 weight percent of a second polycarbonate-siloxane copolymer. In another aspect, the bisphenol A homopolymer may have a weight-average molecular weight of 28,000 to 38,000 g / mol, as determined 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 comprise 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 contain bisphenol A carbonate repeating units and poly(dimethylsiloxane) repeating units.

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

[0088] Also provided are molded, formed, cast, or molded articles comprising polycarbonate compositions. 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. 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 metallizing articles. Exemplary articles may include computer and business machine housings (such as those for monitors, housings for handheld electronic devices (such as those for mobile phones)), electrical connectors, and components for light fixtures, ornaments, household appliances, roofs, greenhouses, sunrooms, swimming pool fences, electronic device packaging, and signage, etc. Furthermore, polycarbonate compositions can be used in applications such as automotive panels and trim.Exemplary but non-limiting examples of suitable articles of article are: exterior and interior parts of aircraft, automobiles, trucks, military vehicles (including automobiles, aircraft, and water vehicles), scooters, and motorcycles, including panels, quarter panels, rocker panels, trim, fenders, doors, deck-lids, trunk lids, hoods, bonnets, roofs, bumpers, dashboards, 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 skid plates; enclosures, housings, panels, and parts for outdoor vehicles and installations; enclosures for electrical and telecommunications installations; outdoor furniture; aircraft parts; marine and marine equipment, including trim, enclosures, and housings; outer motor housings; and other related products. Depth instrument enclosures; personal watercraft; jet skis; pools; spas; hot tubs; steps; step covers; architectural and structural applications such as glass, roofs, windows, floors, 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; enclosures, housings, panels and parts for ATMs; computers; desktop computers; portable computers; laptop computers; handheld computer enclosures; monitors; printers. Keyboards; fax machines; photocopiers; telephones; telephone frames; mobile phones; radio transmitters; radio receivers; perimeters, enclosures, panels, and parts for lawn and garden tractors, mowers, and tools (including lawn and garden tools); window and door trim; sports equipment and toys; enclosures, shells, panels, and parts for snowmobiles; recreational vehicle panels and parts; playground equipment; shoelaces; articles made of plastic-wood composites; golf course markings; utility hole covers; lamps; lighting fixtures; network interface equipment enclosures; transformer enclosures; air conditioner enclosures; cladding for public transport or Seating; 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 products; coated dyed products; coated fluorescent products; coated foam products; medical device housings; battery housings, including those for electric vehicles, electric bicycles, and household and industrial electronics; components for charging equipment for electric vehicles, including wall enclosures, connectors, etc.; wireless charging equipment assemblies; protective covers for electronic devices; kitchen appliance components; and similar applications.

[0089] The compositions of this invention can be particularly used in articles of manufacture for consumer electronics applications. For example, the articles can be components of consumer electronic devices such as game consoles, game controllers, portable gaming devices, mobile phones, televisions, personal computers, tablet computers, laptop computers, personal digital assistants, portable media players, digital cameras, portable music players, electrical appliances, power tools, robots, toys, greeting cards, home entertainment systems, speakers, or sound bars. In one aspect, the articles can be electronic housings for adapters, mobile phones, smartphones, GPS devices, laptops, tablets, e-readers, copiers, or solar-powered devices.

[0090] In one aspect, the article can be a laser-welded article. For example, 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-described composition to a second thermoplastic article may include bringing at least a portion of the surface of the first article into physical contact 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 is absorbed by the second article and generates sufficient heat to weld the first article to the second article. The second thermoplastic article may comprise a variety of thermoplastic polymer compositions that exhibit laser absorption in a manner 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 may include, but are not limited to, olefin polymers, including polyethylene and its copolymers and terpolymers, polybutene and its copolymers and terpolymers, polypropylene and its copolymers and terpolymers; α-olefin polymers, including linear or substantially linear interpolymers and random poly(α-olefins) of ethylene and at least one α-olefin; rubber block copolymers; polyamides; polyimides; polyesters, such as poly(arylate), 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; polystyrene; poly(arylene ethers), including poly(phenylene ethers); polyurethanes; phenoxy resins; polysulfones; polyethers; acetal resins; polyoxyethylene; 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(aryl ethers), and combinations thereof. In specific embodiments, the second article comprises olefinic polymers, polyamides, polyimides, polystyrene, polyaryl ethers, polyurethanes, phenoxy resins, polysulfones, polyethers, acetal resins, polyesters, vinyl polymers, acrylics, epoxy resins, polycarbonates, polyester-polycarbonates, styrene-acrylonitrile copolymers, or combinations thereof. More specifically, the second article may comprise polycarbonate homopolymers or copolymers, polyester homopolymers or copolymers, such as poly(carbonate-ester), and combinations thereof. Laser-welded articles comprising the thermoplastic composition of this disclosure in a first component are also disclosed, the first component being laser-welded to a second component comprising the second thermoplastic composition as described above.

[0091] This disclosure is further illustrated by the following non-limiting embodiments.

[0092] Example

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

[0094] Table 1

[0095]

[0096]

[0097] Components of the mixture and extrusion composition. Molded parts for physical testing are prepared by injection molding. Test methods are described in Table 2 and the following paragraphs.

[0098] Table 2

[0099]

[0100] Flammability testing was conducted according to Underwriters Laboratories Bulletin 94, entitled "Tests for Flammability of Plastic Materials for Parts in Devices and Appliances" (ISBN 0-7629-0082-2), 5th Edition, dated October 29, 1996, with revisions adopted and including December 12, 2003. Several ratings were applied based on burning rate, extinguishing time, resistance to dripping, and whether the drips were flammable. According to this procedure, materials could be classified as UL 94 HB, V0, V1, V2, 5VA, or 5VB. These test samples were aged at 23°C and 50% RH for more than 2 days or at 70°C for 168 hours prior to testing. Specifically, in the UL 94 20mm vertical flame test, a group of five burning rods was tested. For each rod, a flame is applied to the rod and then removed, and the time required for the rod to self-extinguish (first burn-out time, t1) is recorded. The flame is then reapplied and removed, and the time required for the rod to self-extinguish (second burn-out time, t2) and the afterglow time (t3) are recorded. To achieve a V-0 rating, the burn-out times t1 and t2 for each individual sample must be less than or equal to 10 seconds; the total burn-out time for all five samples (t1 plus t2 for all five samples) must be less than or equal to 50 seconds; the second burn-out time plus afterglow time (t2 + t3) for each individual sample must be less than or equal to 30 seconds; no sample must burn or glow up to the holding clamp; and the cotton indicator must not be ignited by burning particles or drips. To achieve a V-1 rating, the burnout times t1 and t2 of each individual sample must be less than or equal to 30 seconds; the total burnout time of all five samples (t1 plus t2 of all five samples) must be less than or equal to 250 seconds; the second burnout time plus afterglow time (t2 + t3) of each individual sample must be less than or equal to 60 seconds; no sample may burn or glow to the holding clamp; and the cotton indicator may not be ignited by burning particles or drips. To achieve a V-2 rating, the burnout times t1 and t2 of each individual sample must be less than or equal to 30 seconds; the total burnout time of all five samples (t1 plus t2 of all five samples) must be less than or equal to 250 seconds; the second burnout time plus afterglow time (t2 + t3) of each individual sample must be less than or equal to 60 seconds; and no sample may burn or glow to the holding clamp; however, the cotton indicator may be ignited by burning particles or drips.

[0101] Environmental stress cracking resistance (ESCR) describes the accelerated failure of polymeric materials due to the combined effects of environment, temperature, and stress. Failure depends primarily on material properties, chemical properties, exposure conditions, and the magnitude of stress. ISO tensile bars are clamped into a semi-circular fixture to apply a constant strain of 1.0%. These bars are then exposed to chemicals at 23°C for a predetermined period. After cleaning, tensile properties are measured at room temperature on standard ASTM tensile test bars at 50 mm / min 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 maintaining a fixed amount of strain for a fixed time, and subsequently performing standard tensile tests, showed that adding PC-Si with a higher Si content can further improve the chemical resistance of the composition. Thus, a composition with a desired balance of color, MVR, and chemical resistance is provided.

[0104] Table 3

[0105]

[0106]

[0107] * indicates a comparative example; "x" indicates a failed sample.

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

[0109] This disclosure further covers the following aspects.

[0110] Aspect 1: A polycarbonate composition comprising: 20 to 85 weight percent of bisphenol A homopolymer polycarbonate; 10 to 55 weight percent of a first polycarbonate-siloxane copolymer, wherein the first polycarbonate-siloxane copolymer has 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, wherein the second polycarbonate-siloxane copolymer has 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 homopolymer polycarbonate has a weight-average molecular weight of 18,000 to 40,000 g / mol, or 20,000 to 40,000 g / mol, or 28,000 to 38,000 g / mol, as determined by gel permeation chromatography relative to a linear bisphenol A polycarbonate standard.

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

[0113] Aspect 4: A 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 percent by weight based on the total weight of the second polycarbonate-siloxane copolymer.

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

[0115] Aspect 6: A 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 a bisphenol A carbonate repeating unit and a poly(dimethylsiloxane) repeating unit.

[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 calibrated using the bisphenol A polycarbonate standard.

[0117] Aspect 8: A polycarbonate composition according to any one of Aspects 1 to 7, wherein, based on the total weight of the polycarbonate composition, the polycarbonate composition further comprises 0.1 to 10 weight percent of an additive composition, preferably wherein the additive composition comprises an anti-dripping 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, more preferably comprising potassium perfluorobutane sulfonate (Rimar salt), potassium perfluorooctane sulfonate, tetraethylammonium perfluorohexane sulfonate, and potassium diphenyl sulfone sulfonate, or combinations thereof; and optionally 0.01 to 1% by weight of an anti-dripping additive.

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

[0119] Aspect 10: The polycarbonate composition according to Aspect 9, wherein the bisphenol A homopolymer has a weight-average molecular weight of 28,000 to 38,000 g / mol 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% by weight based on the total weight of the first polycarbonate-siloxane copolymer; the second polycarbonate-siloxane copolymer has a siloxane content of 35 to 65% by weight based on the total weight of the second polycarbonate-siloxane copolymer; the composition comprises less than 1% by weight of a polycarbonate-siloxane copolymer having a siloxane content of greater than 10 to less than 30% by weight; and the first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer each comprise a bisphenol A carbonate repeating unit and a poly(dimethylsiloxane) repeating unit.

[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 less than or equal to 10 measured by the CIE Lab method using a 10-degree observer, a D65 light source, removal of specular reflection components, and in reflection mode, and using a sample with a thickness of 3.2 mm.

[0121] Aspect 12: A polycarbonate composition according to any one 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: A polycarbonate composition according to any one of Aspects 1 to 12, wherein a molded sample of the composition exhibits 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.

[0123] Aspect 14: A method for manufacturing a polycarbonate composition according to any one of aspects 1 to 13, the method comprising melt-blending components of the composition, and optionally, extruding the composition.

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

[0125] Alternatively, the composition, method, and article may comprise, consist of, or consist substantially of any suitable materials, steps, or components disclosed herein. The composition, method, and article may additionally, or alternatively, be formulated to be free of or substantially free of any materials (or species), steps, or components that would otherwise be unnecessary for achieving the function or purpose of the composition, method, and article.

[0126] All scopes disclosed herein include endpoints, and endpoints may be combined independently of each other. "Combination" includes blends, mixtures, alloys, reaction products, etc. The terms "first," "second," etc., do not indicate any order, quantity, or importance, but are used to distinguish one element from another. Unless otherwise stated herein or clearly contradicted by the context, the terms "a," "an," and "the" do not indicate a limitation of quantity, but are interpreted to cover both singular and plural. Unless otherwise expressly stated, "or" means "and / or." Throughout the specification, reference to "an aspect" means that a particular element described in connection with that aspect is included in at least one aspect described herein and may or may not exist in other aspects. The term "combination of them," as used herein, includes one or more listed elements and is open to the presence of one or more unnamed similar elements. Furthermore, it should be understood that the described elements may be combined in any suitable manner in each aspect.

[0127] Unless otherwise specified herein, all test standards are the most recent standards effective from the filing date of this application, or, if priority is claimed, the most recent standards effective from 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 meaning as commonly understood by one of ordinary skill in the art to which this application pertains. All cited patents, patent applications, and other references are incorporated herein by reference in their entirety. However, if any terminology in this application contradicts or conflicts with a terminology in an incorporated reference, the terminology from this application shall take precedence over the conflicting terminology from the incorporated reference.

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

[0130] As used herein, the term "alkyl group," whether used alone or as a prefix, suffix, or part of another term, refers to a residue containing only carbon and hydrogen. This residue can be aliphatic or aromatic, linear, cyclic, bicyclic, branched, saturated, or unsaturated. It can also contain combinations of aliphatic, aromatic, linear, cyclic, bicyclic, branched, saturated, and unsaturated hydrocarbon moieties. However, when an alkyl group residue is described as substituted, it may optionally contain heteroatoms above and above the carbon and hydrogen members of the substituent residue. Thus, when specifically described as substituted, an alkyl group residue may also contain one or more carbonyl, amino, hydroxyl, etc., or it may contain heteroatoms within the backbone of the alkyl group residue. The term "alkyl" refers to a branched or linear, saturated aliphatic alkyl group, such as 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-chain or branched monovalent hydrocarbon group having at least one carbon-carbon double bond (e.g., vinyl (-HC=CH2)). "Alkoxy" refers to an alkyl group linked via oxygen (i.e., alkyl-O-), such as methoxy, ethoxy, and sec-butoxy. "Alkylene" refers to a straight-chain or branched, saturated, divalent aliphatic hydrocarbon group (e.g., methylene (-CH2-) or propylidene (-(CH2)3-)). "Cycloalkylene" refers to a divalent cyclic alkylene group, -C n H 2n-x Where x is the number of hydrogen atoms substituted by cyclization. "Cycloalkenyl" refers to a monovalent group having one or more rings and one or more carbon-carbon double bonds within those rings, 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, indenyl, or naphthyl. "Arylene" refers to a divalent aryl group. "Alkyleneene" refers to an aryl group substituted with an alkyl group. "Arylalkylene" refers to an alkylene group substituted with an aryl group (e.g., benzyl). The prefix "halogenated" refers to a group or compound comprising one or more of fluorine, chlorine, bromine, or iodine substituents. Combinations of different halogen atoms (e.g., bromine and fluorine) or only chlorine atoms may be present. The prefix "heterogeneous" refers to a compound or group comprising at least one ring member containing heteroatoms (e.g., 1, 2, or 3 heteroatoms), wherein each heteroatom is independently N, O, S, Si, or P. "Substituted" means that a compound or group is substituted by at least one (e.g., 1, 2, 3, or 4) substituents, each of which can be C16 or C26 independently. 1-9 Alkoxy, C 1-9 Halogenated alkoxy, nitro (-NO2), cyano (-CN), C 1-6 alkylsulfonyl (-S(=O)2-alkyl), C 6-12Arylsulfonyl (-S(=O)2-aryl), thiol (-SH), thiocyanate (-SCN), toluenesulfonyl (CH3C6H4SO2-), C 3-12 cycloalkyl, C 2-12 alkenyl, C 5-12 Cycloalkenyl, C 6-12 Aryl, C 7-13 Arylalkylene, C 4-12 Heterocyclic alkyl groups, and C 3-12 Heteroaryl groups, not hydrogen, are used, provided that the valence of the substituted atom does not exceed the normal valence of the substituted atom. The number of carbon atoms indicated in the group does not include any substituents. For example, -CH2CH2CN is a C2 alkyl group substituted with a nitrile.

[0131] While specific embodiments have been described, alternatives, modifications, variations, improvements, and substantial equivalents may be conceived by the applicant or others skilled in the art that are currently unforeseeable or likely to be unforeseeable. Therefore, the appended claims, as filed and as they may be modified, 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 a bisphenol A homopolycarbonate; 10 to 55 weight percent of 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 10 to 25 weight percent of 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; 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.

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

3. The polycarbonate composition of claim 1 or 2, wherein the first polycarbonate-siloxane copolymer has a siloxane content of 4 to less than 10 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 of claim 1 or 2, 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 of claim 1 or 2, wherein, the second polycarbonate-siloxane copolymer is present in the composition in an amount of greater than 15 to 25 weight percent based on the total weight of the composition.

6. The polycarbonate composition of claim 1 or 2, wherein, The first polycarbonate-siloxane copolymer and the second polycarbonate-siloxane copolymer each comprise bisphenol A carbonate repeat units and poly(dimethylsiloxane) repeat units.

7. The polycarbonate composition of claim 1 or 2, wherein, The second polycarbonate-siloxane copolymer has a weight average molecular weight of 21,000 to 50,000 g / mol as determined by gel permeation chromatography at a sample concentration of 1 milligram / milliliter using a crosslinked styrene-divinylbenzene column and calibrated using bisphenol A polycarbonate standards.

8. The polycarbonate composition of claim 1 or 2, 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.

9. The polycarbonate composition of claim 8, wherein, The additive composition comprises an anti-drip agent, a flame retardant, a colorant composition, or a combination thereof.

10. The polycarbonate composition of claim 8, wherein, The additive composition comprises: 0.05 to 1 weight percent of an inorganic flame retardant; and optionally 0.01 to 1 weight percent of an anti-drip additive.

11. The polycarbonate composition of claim 10, wherein, The inorganic flame retardant comprises C 1-16 Sulfonate.

12. The polycarbonate composition of claim 10, wherein, The inorganic flame retardant comprises potassium perfluorobutane sulfonate (Rimar salt), potassium perfluoroctane sulfonate, tetraethylammonium perfluorohexane sulfonate, and potassium diphenyl sulfone sulfonate, or a combination thereof.

13. The polycarbonate composition of claim 1 or 2, 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.

14. The polycarbonate composition of claim 13, wherein the bisphenol A homopolycarbonate has a weight average molecular weight of 28,000 to 38,000 grams per 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 repeat units and poly(dimethylsiloxane) repeat units.

15. The polycarbonate composition of claim 1 or 2, wherein, Molded samples of the composition exhibit an L value of less than or equal to 10 by the CIE Lab method using a 10 degree observer, D65 illuminant, removing the specular component of reflection, and measuring at an angle of incidence of 2 degrees, and using a sample having a thickness of 3.2 millimeters.

16. The polycarbonate composition of claim 1 or 2, wherein, 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 after exposure to a sunscreen or insect repellent.

17. The polycarbonate composition of claim 1 or 2, wherein, a molded sample of the composition exhibits a UL-94 burn rating of V0 or VI at a thickness of 1.5 millimeters or less.

18. The polycarbonate composition of claim 17, wherein, a molded sample of the composition exhibits a UL-94 burn rating of V0 or VI at a thickness of 1.2 millimeters or less.

19. A method of making the polycarbonate composition of any one of claims 1 to 18, the method comprising melt mixing the components of the composition, and optionally, extruding the composition.

20. An article comprising the polycarbonate composition of any one of claims 1 to 18.

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