The composition comprises less than 5 weight percent or less than or equal to 1 weight percent, or less than or equal to 0.1 weight percent of a polycarbonate-siloxane having a siloxane content of less than 30 weight percent, or a siloxane content of less than 10 weight percent. Preferably a polycarbonate-siloxane having a siloxane content of less than 30 weight percent or a siloxane content of less than 10 weight percent is excluded from the composition.

The polycarbonate-siloxane copolymer can be present in the composition in an amount to provide a total siloxane content of 3 to 14 weight percent, or 3 to 12 weight percent, or 3 to 10 weight percent, or 3 to 8 weight percent, or 3 to 6 weight percent or 3 to 4 weight percent, or 3 to 7.5 weight percent, or 7.5 to 14 weight percent, each based on the total weight of the polycarbonate composition.

The polycarbonate-siloxane copolymer can be present in the composition in an amount of 10 to 20 weight percent, based on the total weight of the composition. Within this range, the polycarbonate-siloxane copolymer can be present in an amount of, for example, greater than 12 to 20 weight percent, or 12 to 18 weight percent, or 13 to 17 weight percent, each based on the total weight of the composition.

In an aspect, one or both of the bisphenol A homopolycarbonate and the polycarbonate-siloxane copolymer can be derived from post-consumer recycled or post-industrial recycled materials. In an aspect, one or both of the bisphenol A homopolycarbonate and the polycarbonate-siloxane copolymer can be produced from at least one monomer derived from bio-based or plastic waste feedstock.

The polycarbonate composition can optionally further comprise an additive composition comprising one or more additives ordinarily incorporated into polymer compositions of this type, provided that the one or more additives are selected so as not to significantly adversely affect the desired properties of the polycarbonate composition, in particular impact, chemical resistance, and flame retardance. 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 such as titanium dioxide, carbon black, and organic dyes, surface effect additives, radiation stabilizers, flame retardants, and anti-drip agents. A combination of additives can be used, for example a combination of a heat stabilizer, mold release agent, and ultraviolet light stabilizer. In general, the additives are used in the amounts generally known to be effective. For example, the total amount of the additives (other than any impact modifier, filler, or reinforcing agents) can be 0.01 to 5 weight percent, based on the total weight of the polycarbonate composition. In an aspect, the polycarbonate composition comprises no more than 5 weight percent based on the weight of the composition of a processing aid, a heat stabilizer, an antioxidant, an ultraviolet light absorber, a colorant, or a combination thereof.

In an aspect, the composition can optionally further comprise a flame retardant. Useful flame retardants can include organic compounds that include phosphorus, bromine, or chlorine. Non-brominated and non-chlorinated phosphorus-containing flame retardants can be preferred in certain applications for regulatory reasons, for example organic phosphates and organic compounds containing phosphorus-nitrogen bonds.

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, tritolyl phosphate, bis(2-ethylhexyl)phenyl phosphate, tri (nonylphenyl)phosphate, bis(dodecyl) p-tolyl phosphate, dibutyl phenyl phosphate, 2-chloroethyl diphenyl phosphate, p-tolyl bis(2,5,5′-trimethylhexyl)phosphate, and 2-ethylhexyl diphenyl phosphate. Di- or polyfunctional aromatic phosphorus-containing compounds are also useful, for example resorcinol tetraphenyl diphosphate (RDP), the bis(diphenyl)phosphate of hydroquinone and the bis(diphenyl) phosphate of bisphenol A, respectively, and their oligomeric and polymeric counterparts.

Flame retardant compounds containing phosphorus-nitrogen bonds include phosphazenes, phosphonitrilic chloride, phosphorus ester amides, phosphoric acid amides, phosphonic acid amides, phosphinic acid amides, and tris(aziridinyl)phosphine oxide. These flame-retardant additives are commercially available.

Halogenated materials can also be used as flame retardants, for example bisphenols of which the following are representative: 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 decabromo diphenyl oxide, as well as oligomeric and polymeric halogenated aromatic compounds, such as a copolycarbonate of bisphenol A and tetrabromobisphenol A and a carbonate precursor, e.g., phosgene. Metal synergists, e.g., antimony oxide, can also be used with the flame retardant.

Alternatively, the thermoplastic composition can be essentially free of chlorine and bromine. “Essentially free of chlorine and bromine” is defined as having a bromine or chlorine content of less than or equal to 100 parts per million by weight (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.

Inorganic flame retardants can also be used, for example salts of C_1-16alkyl sulfonate salts such as potassium perfluorobutane sulfonate (Rimar salt), potassium perfluoroctane sulfonate, tetraethylammonium perfluorohexane sulfonate, and potassium diphenylsulfone sulfonate; salts such as Na₂CO₃, K₂CO₃, MgCO₃, CaCO₃, and BaCO₃, or fluoro-anion complexes such as Li₃AlF₆, BaSiF₆, KBF₄, K₃AlF₆, KAlF₄, K₂SiF₆, or Na₃AlF₆.

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 total weight of the composition. In an 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.

Heat stabilizer additives can include organophosphites (e.g., triphenyl phosphite, tris-(2,6-dimethylphenyl)phosphite, tris-(mixed mono- and di-nonylphenyl)phosphite or the like), phosphonates (e.g., dimethylbenzene phosphonate or the like), phosphates (e.g., trimethyl phosphate, or the like), or a combination thereof. The heat stabilizer can be tris(2,4-di-t-butylphenyl)phosphate available as IRGAPHOS 168. Heat stabilizers are generally used in amounts of 0.01 to 5 wt %, based on the total weight of polymer in the composition.

Light stabilizers or ultraviolet light (UV) absorbing additives, also referred to 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-octoxy benzophenone, or the like, or a combination thereof.

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 1164); 2,2′-(1,4-phenylene)bis(4H-3,1-benzoxazin-4-one) (CYASORB UV-3638); poly[(6-morphilino-s-triazine-2,4-diyl)[2,2,6,6-tetramethyl-4-piperidyl)imino]-hexamethylene[(2,2,6,6-tetramethyl-4-piperidyl)imino], 2-hydroxy-4-octyloxybenzophenone (UVINUL™ 3008), 6-tert-butyl-2-(5-chloro-2H-benzotriazole-2-yl)-4-methylphenyl (UVINUL™3026), 2,4-di-tert-butyl-6-(5-chloro-2H-benzotriazole-2-yl)-phenol (UVINUL™3027), 2-(2H-benzotriazole-2-yl)-4,6-di-tert-pentylphenol (UVINUL3028), 2-(2H-benzotriazole-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-benzotriazole-2-yl)-4-methylphenol (UVINUL3033), 2-(2H-benzotriazole-2-yl)-4,6-bis(1-methyl-1-phenyethyl)phenol (UVINUL3034), ethyl-2-cyano-3,3-diphenylacrylate (UVINUL3035), (2-ethylhexyl)-2-cyano-3,3-diphenylacrylate (UVINUL3039), N,N′-bisformyl-N,N′-bis(2,2,6,6-tetramethyl-4-piperidinyl)hexamethylendiamine (UVINUL4050H), bis-(2,2,6,6-tetramethyl-4-piperidyl)-sebacate (UVINUL4077H), bis-(1,2,2,6,6-pentamethyl-4-piperdiyl)-sebacate+methyl-(1,2,2,6,6-pentamethyl-4-piperidyl)-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; TINUVIN 234; nano-size inorganic materials such as titanium oxide, cerium oxide, and zinc oxide, all with particle size less than or equal to 100 nanometers; or the like, or a combination thereof. UV absorbers can be used in amounts of 0.01 to 1 part by weight, based on 100 parts by weight of polycarbonate and impact modifier. UV absorbers that can be particularly useful with the polycarbonate compositions disclosed herein include 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)-phenol (e.g., CYASORB 5411 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 stabilizers can 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 upon the total weight of the polycarbonate composition.

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

Anti-drip agents can also be used in the composition, for example a fibril forming or non-fibril forming fluoropolymer such as polytetrafluoroethylene (PTFE). The anti-drip agent can be encapsulated by a rigid copolymer, for example styrene-acrylonitrile copolymer (SAN). PTFE encapsulated in SAN is known as TSAN. An TSAN comprises 50 wt % PTFE and 50 wt % SAN, based on the total weight of the encapsulated fluoropolymer. The SAN can comprise, for example, 75 wt % styrene and 25 wt % acrylonitrile based on the total weight of the copolymer. Anti-drip agents can be used in amounts of 0.1 to 5 weight percent, or 0.1 to 2 weight percent, based on the total weight of the composition.

In an aspect, the polycarbonate can comprise a colorant composition. Suitable colorants can include, but are not limited to, those known under their Color Index numbers 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 dyes, 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 foregoing colorants.

Colorants can be employed in amounts and combinations sufficient to render the molded article dark and opaque, and more specifically to provide the lightness values described below. The specific amount of a colorant employed can depend on, among other factors, its solubility and extinction coefficient in the polycarbonate composition, and whether it is being employed in combination with one or more additional colorants. Suitable amounts and combinations can readily be determined by those of ordinary skill in the art guided by the present disclosure. Typical colorant amounts 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.

In an aspect, when present, the colorant composition can provide the polycarbonate composition having a black color.

The polycarbonate composition can optionally exclude other components not specifically described herein. For example, the polycarbonate composition can exclude thermoplastic polymers other than the bisphenol A homopolycarbonate and the polycarbonate-siloxane copolymers. For example the composition can minimize or exclude polyesters (e.g., a polyester can be present in an amount of 1 weight percent or less, preferably wherein a polyester is excluded from the composition). The composition can optionally minimize or exclude a polycarbonate other than the bisphenol A homopolycarbonate and the polycarbonate-siloxane copolymer, for example a polyester-carbonate or a bisphenol A copolycarbonate different from the polycarbonate-siloxane copolymer. The polycarbonate composition can optionally minimize or exclude impact modifiers, for example silicone-based impact modifiers different from the poly(carbonate-siloxane) copolymer, methyl methacrylate-butadiene-styrene copolymers, acrylonitrile-butadiene, styrene copolymers, and the like, or a combination thereof. The composition can minimize or exclude halogenated flame retardants, for example brominated flame retardants, including brominated polycarbonate (e.g., a polycarbonate containing brominated carbonate includes units derived from 2,2′,6,6′-tetrabromo-4,4′-isopropylidenediphenol (TBBPA) and carbonate units derived from at least one dihydroxy aromatic compound that is not TBBPA), brominated epoxies, and the like or combinations thereof. The composition can optionally exclude a phosphorous-containing flame retardant.

The composition of the present disclose can advantageously exhibit one or more desirable properties. For example, it was surprisingly found that the composition can exhibit a low melt volume rate (MVR). For example, the polycarbonate composition can have a melt volume rate of less than or equal to 10 cm³/10 minutes, as determined according to ISO1133 under a load of 2.16 kg at 300° C. with a dwell time of 300 seconds. The polycarbonate composition can further exhibit a low melt viscosity (MV) indicating the material is well processable despite the relatively low MVR. For example, in an aspect, the polycarbonate composition can have a melt viscosity of less than 200 Pa-s, as determined according to ISO11443 at a shear rate of 5000 s⁻¹.

It was further unexpectedly discovered that using a high siloxane content polycarbonate-siloxane copolymer in combination with a bisphenol A homopolycarbonate having a particular molecular weight, good chemical resistance and aesthetic properties could also be obtained.

The composition can have good chemical resistance. In an aspect, a molded sample of the polycarbonate composition can have a tensile strain at break of at least 50% of the tensile strain at break of a non-exposed reference tested at the same temperature after exposure of an ISO tensile bar for 72 hours to insect repellent or sunscreen at a temperature of 23° C. under 1% strain.

The polycarbonate composition can further exhibit good black 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 with a 10 degree observer, D65 illuminant, specular component excluded, and measured in reflectance mode, and using a sample having a thickness of 3.2 millimeters.

In an aspect, the composition can also exhibit good flame retardancy. In an aspect of measuring flame retardance, the UL94 standard utilizes a rating of V0. V1, V2 or HB, wherein a rating of V0 is better than V1 or V2 and is required for many applications at the actual part thickness. Using this standard, the polycarbonate compositions are formed into a molded article having a given thickness. The thinner the article, the more difficult it is to achieve a rating of V0 or V1. In an aspect, a molded sample of the polycarbonate composition is capable of achieving a UL-94 V0 or V1 rating at a thickness of 1.5 millimeters or less, preferably a UL-94 rating of V0 or V1 at a thickness of less than or equal to 1.2 millimeters.

The polycarbonate composition according to the present disclosure can comprise 80 to 90 weight percent of a bisphenol A homopolycarbonate having a weight average molecular weight of 28,000 or more, determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards; and 10 to 20 weight percent of a polycarbonate-siloxane copolymer having a siloxane content of 30 to 70 weight percent, based on the total weight of the polycarbonate-siloxane copolymer; wherein the composition comprises less than 5 weight percent of a polycarbonate-siloxane copolymer having a siloxane content of less than 30 weight percent. The polycarbonate composition can have a melt volume rate of less than or equal to 10 cm³/10 minutes, as determined according to ISO1133 under a load of 2.16 kg at 300° C. with a dwell time of 300 seconds. The bisphenol A homopolycarbonate can have a weight average molecular weight of 29,000 to 45,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards. The bisphenol A homopolycarbonate can comprise a first linear bisphenol A homopolycarbonate having a weight average molecular weight of 32,000 to 38,000 grams per mole, preferably 34,000 to 36,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards; or a second linear bisphenol A homopolycarbonate having a weight average molecular weight of 29,000 to 32,000 grams per mole, preferably 30,000 to 31,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards; or a combination thereof. The polycarbonate composition can optionally further comprise a bisphenol A homopolycarbonate having a molecular weight of 18,000 to 24,000 g/mol, preferably 20,000 to 22,000 g/mol, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards, provided that a weight ratio of bisphenol A homopolycarbonate having a weight average molecular weight of 28,000 g/mol or more to the bisphenol A homopolycarbonate having a molecular weight of 18,000 to 24,000 g/mol is greater than 1:1, preferably greater than 2:1. The polycarbonate-siloxane copolymer can have a siloxane content of 35 to 65 weight percent, based on the total weight of the polycarbonate-siloxane copolymer. The polycarbonate-siloxane copolymer can comprise bisphenol A carbonate repeating units and poly(dimethyl siloxane) repeating units. The polycarbonate-siloxane copolymer can have 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 crosslinked styrene-divinyl benzene column, at a sample concentration of 1 milligram per milliliter, and as calibrated with bisphenol A polycarbonate standards. The composition can be free of a polycarbonate-siloxane copolymer having a siloxane content of less than 30 weight percent. The polycarbonate composition can further comprise 0.1 to 10 weight percent, based on the total weight of the polycarbonate composition, of an additive composition. A molded sample of the composition exhibits one or more of: a UL-94 rating of V0 at a thickness of 1.5 millimeters or less; preferably a UL-94 rating of V0 at a thickness of less than or equal to 1.2 millimeters; an L* value of less than or equal to 10 as measured by the CIE Lab method, 10 degree observer, D65 illuminant, specular component excluded, measured in reflectance mode; and a tensile strain at break that is at least 50% of the tensile strain at break of a non-exposed reference sample after exposure to sunscreen or insect repellent.

The polycarbonate composition can be manufactured by various methods known in the art. For example, powdered polycarbonate homopolymer, poly(carbonate-siloxane) and other optional components are first blended, optionally with any fillers, in a high-speed mixer or by hand mixing. The blend is then fed into the throat of a twin-screw extruder via a hopper. Alternatively, at least one of the components can be incorporated into the composition by feeding it directly into the extruder at the throat and/or downstream through a side stuffer, or by being compounded into a masterbatch with a desired polymer and fed into the extruder. The extruder is generally operated at a temperature higher than that necessary to cause the composition to flow. The extrudate can be immediately quenched in a water bath and pelletized. The pellets so prepared can be one-fourth inch long or less as desired. Such pellets can be used for subsequent molding, shaping, or forming.

Shaped, formed, casted, or molded articles comprising the polycarbonate composition are also provided. The polycarbonate composition can be molded into useful shaped articles by a variety of methods, such as injection molding, extrusion, rotational molding, blow molding, and thermoforming. The article can be a molded article, a thermoformed article, an extruded film, an extruded sheet, a honeycomb structure, one or more layers of a multi-layer article, a substrate for a coated article, and a substrate for a metallized article. Exemplary articles can include computer and business machine housings such as housings for monitors, handheld electronic device housings such as housings for cell phones, electrical connectors, and components of lighting fixtures, ornaments, home appliances, roofs, greenhouses, sunrooms, swimming pool enclosures, electronic device casings and signs and the like. In addition, the polycarbonate compositions can be used for such applications as automotive panel and trim. Examples of suitable articles are exemplified by but are not limited to aircraft, automotive, truck, military vehicle (including automotive, aircraft, and water-borne vehicles), scooter, and motorcycle exterior and interior components, including panels, quarter panels, rocker panels, trim, fenders, doors, deck-lids, trunk lids, hoods, bonnets, roofs, bumpers, fascia, grilles, mirror housings, pillar appliqués, cladding, body side moldings, wheel covers, hubcaps, door handles, spoilers, window frames, headlamp bezels, headlamps, tail lamps, tail lamp housings, tail lamp bezels, license plate enclosures, roof racks, and running boards; enclosures, housings, panels, and parts for outdoor vehicles and devices; enclosures for electrical and telecommunication devices; outdoor furniture; aircraft components; boats and marine equipment, including trim, enclosures, and housings; outboard motor housings; depth finder housings; personal water-craft; jet-skis; pools; spas; hot tubs; steps; step coverings; building and construction applications such as glazing, roofs, windows, floors, decorative window furnishings or treatments; treated glass covers for pictures, paintings, posters, and like display items; wall panels, and doors; counter tops; protected graphics; outdoor and indoor signs; enclosures, housings, panels, and parts for automatic teller machines (ATM); computer; desk-top computer; portable computer; lap-top computer; hand held computer housings; monitor; printer; keyboards; FAX machine; copier; telephone; phone bezels; mobile phone; radio sender; radio receiver; enclosures, housings, panels, and parts for lawn and garden tractors, lawn mowers, and tools, including lawn and garden tools; window and door trim; sports equipment and toys; enclosures, housings, panels, and parts for snowmobiles; recreational vehicle panels and components; playground equipment; shoe laces; articles made from plastic-wood combinations; golf course markers; utility pit covers; light fixtures; lighting appliances; network interface device housings; transformer housings; air conditioner housings; cladding or seating for public transportation; cladding or seating for trains, subways, or buses; meter housings; antenna housings; cladding 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 for electric vehicles, electric bikes, and home and industrial electronics; components of charging equipment for an electric vehicle, including wall box housings, connectors, and the like; wireless charging device components; electronic device protection covers; kitchen appliance components; and like applications.

The composition of the present disclosure can be particularly useful in articles for consumer electronic applications. For example, the articles can be a component of a consumer electronic device such as a gaming console, a gaming controller, a portable gaming device, a cellular telephone, 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 loudspeaker, or a soundbar. In an aspect, the articles can be an electronic housing for an adapter, a cell phone, a smart phone, a GPS device, a laptop computer, a tablet computer, an e-reader, a copier, or a solar apparatus.

In an aspect, the article can be a laser-welded article. For example, parts or articles as described above can be assembled into an article by laser welding. For example, a process for welding a first article comprising the above-described composition to a second thermoplastic article can include physically contacting at least a portion of a surface of the first article with at least a portion of a 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 sufficient heat is generated to weld the first article to the second article. The second thermoplastic article can comprise a wide variety of thermoplastic polymer compositions that have been rendered laser absorbing by means known to those of skill 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, olefinic polymers, including polyethylene and its copolymers and terpolymers, polybutylene and its copolymers and terpolymers, polypropylene and its copolymers and terpolymers; alpha-olefin polymers, including linear or substantially linear interpolymers of ethylene and at least one alpha-olefin and atactic poly(alpha-olefins); rubbery block copolymers; polyamides; polyimides; polyesters such as poly(arylates), poly(ethylene terephthalate) and poly(butylene terephthalate); vinylic polymers such as polyvinyl chloride and polyvinyl esters such as polyvinyl acetate; acrylic homopolymers, copolymers and terpolymers; epoxies; polycarbonates, polyester-polycarbonates; polystyrene; poly(arylene ethers), including poly(phenylene ether); polyurethanes; phenoxy resins; polysulfones; polyethers; acetal resins; polyoxyethylenes; and combinations thereof. More particularly, the polymers are selected from the group consisting of polyethylene, ethylene copolymers, polypropylene, propylene copolymers, polyesters, polycarbonates, polyester-polycarbonates, polyamides, poly(arylene ether)s, and combinations thereof. In a specific embodiment, the second article comprises an olefinic polymer, polyamide, polyimide, polystyrene, polyarylene ether, polyurethane, phenoxy resin, polysulfone, polyether, acetal resin, polyester, vinylic polymer, acrylic, epoxy, polycarbonate, polyester-polycarbonate, styrene-acrylonitrile copolymers, or a combinations thereof. More specifically, the second article can comprise a polycarbonate homopolymer or copolymer, polyester homopolymer or copolymer, e.g., a poly(carbonate-ester) and combinations thereof. Also disclosed are laser-welded articles comprising the thermoplastic composition of the present disclosure in a first component laser-welded to a second component comprising a second thermoplastic composition as described above.

This disclosure is further illustrated by the following examples, which are non-limiting.

EXAMPLES

Materials used for the following examples are shown in Table 1.

TABLE 1

Component
Description
Supplier

PC-1
Linear bisphenol A polycarbonate, CAS Reg. No, 25971-63-5, having
SABIC

a molecular weight (Mw) of 34,000-36,000 grams per mole, as

determined by gel permeation chromatography relative to linear

bisphenol A polycarbonate standards, produced via interfacial

polymerization and end-capped with phenol

PC-2
Linear bisphenol A polycarbonate, CAS Reg. No, 25971-63-5, having
SABIC

a molecular weight (Mw) of 30,000-31,000 grams per mole, as

determined by gel permeation chromatography relative to linear

bisphenol A polycarbonate standards, produced by interfacial

polymerization and endcapped with phenol

PC-3
Linear bisphenol A polycarbonate having a Mw of 20,000-22,000
SABIC

grams per mole, as determined by gel permeation chromatography

relative to linear bisphenol A polycarbonate standards, produced by

interfacial polymerization and endcapped with p-cumylphenol

PC-Si-1
Polycarbonate-siloxane copolymer having a siloxane content of 40
SABIC

weight percent, average PDMS block length of 45 units, having a Mw

of 37,000 to 38,000 grams per mole as determined by gel permeation

chromatography relative to linear bisphenol A polycarbonate standards,

produced by interfacial polymerization and endcapped with p-cumylphenol

PC-Si-2
Polycarbonate-siloxane copolymer having a siloxane content of 20
SABIC

weight percent, average PDMS block length of 45 units, having a Mw

of 28,000 to 32,000 grams per mole as determined by gel permeation

chromatography relative to linear bisphenol A polycarbonate standards,

produced by interfacial polymerization and endcapped with p-cumylphenol

TBPP
Tris(2,4-di-tert-butylphenyl) phosphite, CAS Reg. No. 31570-04-4;
BASF

available as IRGAFOS 168

BZT
Phenol, 2-(2H-benzotriazol-2-y])-4,6-bis(1-methyl-1-phenylethyl),
BASF

CAS Reg. No. 70321-86-7; available as TINUVIN 234

PETS
Pentaerythritol tetrastearate
FACI

TSAN
Polyacrylonitrile-encapsulated polytetrafluoroethylene having 50
SABIC

weight percent polytetrafluoroethylene; obtained as CYCOLAC

INP449 Resin

Green Dye
Solvent Green 3, obtained as MACROLEX Green 5B
Lanxess

Red Dye
Solvent Red 135, obtained as MACROLEX Red EG
Lanxess

Yellow Dye
Solvent Yellow 163, obtained as FARBTEX YELLOW GHS
Farbtex

Yellow Pigment
Pigment yellow 138, CAS Reg. No. 30125-47-4
BASF

KSS
Potassium diphenylsulfonesulfonate, CAS Reg. No. 63316-43-8
Arichem

TiO₂
Titanium dioxide

Components of the compositions were compounded and extruded. Molded parts for physical testing were prepared by injection molding. Test methods are described below in Table 2.

TABLE 2

Test and Condition
Unit
Specimen
Standard

Melt Volume Rate (MVR), 300° C., 300 s,
cm³/10 min
Pellet, pre-dried
ISO1133

various load

Izod Impact, notched, various temp
J/m
3.2 mm bar
ASTM D 256

Heat Deflection Temperature (HDT), 1.82
° C.
3.2 mm flexural
ASTM D 648

MPa

bar

Melt viscosity (MV), 300° C.
Pa-s
Pellet, pre-dried
ISO11443

Tensile Modulus, 5 mm/min
MPa
Type I bar
ASTM D 638

Tensile Stress at yield, Type I, 50 mm/min
MPa
Type I bar
ASTM D 638

Tensile stress at break, Type I, 50 mm/min
Mpa
Type I bar
ASTM D 638

Tensile Strain at yield, Type I, 50 mm/min
%
Type I bar
ASTM D 638

Tensile Strain at break, Type I, 50 mm/min
%
Type I bar
ASTM D 638

FR at 23° C./50% RH for 48 hrs
/
127 × 12.7 ×
UL 94 V test

Thickness

Color: L*, a*, b*; D65 illuminant; 10°
/
3.2 millimeters
ASTM E 308-08

observer; specular component excluded;

thickness

measured in reflection mode

Flammability tests were performed following the procedure 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 Oct. 29, 1996, incorporating revisions through and including Dec. 12, 2003. Several ratings can be applied based on the rate of burning, time to extinguish, ability to resist dripping, and whether or not drips are burning. According to this procedure, materials can be classified as UL94 HB, V0, V1, V2, 5VA, or 5VB. The test specimens were aged at 23° C., 50% RH for more than 2 days or 70° C. for 168 hours before testing. Specifically, in the UL 94 20 mm Vertical Burning Flame Test, a set of five flame bars was tested. For each bar, a flame was applied to the bar then removed, and the time required for the bar to self-extinguish (first afterflame time, t1) was noted. The flame was then reapplied and removed, and the time required for the bar to self-extinguish (second afterflame time, t2) and the post-flame glowing time (afterglow time, t3) were noted. To achieve a rating of V-0, the afterflame times t1 and t2 for each individual specimen must have been less than or equal to 10 seconds; and the total afterflame time for all five specimens (t1 plus t2 for all five specimens) must have been less than or equal to 50 seconds; and the second afterflame time plus the afterglow time for each individual specimen (t2+t3) must have been less than or equal to 30 seconds; and no specimen can have flamed or glowed up to the holding clamp; and the cotton indicator cannot have been ignited by flaming particles or drops. To achieve a rating of V-1, the afterflame times t1 and t2 for each individual specimen must have been less than or equal to 30 seconds; and the total afterflame time for all five specimens (t1 plus t2 for all five specimens) must have been less than or equal to 250 seconds; and the second afterflame time plus the afterglow time for each individual specimen (t2+t3) must have been less than or equal to 60 seconds; and no specimen can have flamed or glowed up to the holding clamp; and the cotton indicator cannot have been ignited by flaming particles or drops. To achieve a rating of V-2, the afterflame times t1 and t2 for each individual specimen must have been less than or equal to 30 seconds; and the total afterflame time for all five specimens (t1 plus t2 for all five specimens) must have been less than or equal to 250 seconds; and the second afterflame time plus the afterglow time for each individual specimen (t2+t3) must have been less than or equal to 60 seconds; and no specimen can have flamed or glowed up to the holding clamp; but the cotton indicator can have been ignited by flaming particles or drops.

Environmental stress cracking resistance (ESCR) describes the accelerated failure of polymeric materials, as a combined effect of environment, temperature, and stress. The failure mainly depends on the characteristics of the material, chemical, exposure condition, and the magnitude of the stress. The ISO tensile bars were clamped to a semicircular jig to impart a constant strain of 1.0%. The bars were than exposed to the chemical for pre-defined time period at 23° C. After cleaning, tensile properties were measured in accordance with ASTM D638 at 50 mm/min at room temperature on standard ASTM tensile bars.

Examples 1-3

Table 5 shows the compositions and properties for the compositions according to Examples 1-3. As can be seen in Table 5, the color (i.e., the L*, a*, and b*) values were unexpectedly improved as the molecular weight of the bisphenol A homopolycarbonate component increases. The amount of each component is expressed in weight percent based on the total weight of the composition.

TABLE 5

Unit
1
2
3*

Component

PC-1
wt %
83.45

PC-2
wt %

83.45

PC-3
wt %

83.45

PC-Si-1
wt %
15
15
15

TBPP
wt %
0.09
0.09
0.09

BZT
wt %
0.3
0.3
0.3

PETS
wt %
0.1
0.1
0.1

TSAN
wt %
0.5
0.5
0.5

Green Dye
wt %
0.13
0.13
0.13

Red Dye
wt %
0.13
0.13
0.13

KSS
wt %
0.3
0.3
0.3

Properties

UL94 Rating, 1.5

V0
V0
V0

mm

UL94 Rating, 1.2

V0
V0
V0

mm

MVR, 2.16 kg,
cm³/10 min
3.4
6.4
21.5

300 C.

HDT, 1.8 MPa
° C.
123
123
118

HDT, 0.45 MPa

138
136
133

MV, 100 s⁻¹
Pa-s
1293
775
258

MV, 200 s⁻¹
Pa-s
969
618
248

MV, 500 s⁻¹
Pa-s
671
396
217

MV, 1000 s⁻¹
Pa-s
473
269
180

MV, 2000 s⁻¹
Pa-s
382
260
151

MV, 3500 s⁻¹
Pa-s
263
189
112

MV, 5000 s⁻¹
Pa-s
195
156
89

MV, 7000 s⁻¹
Pa-s
149

73

NII, 23° C.
kJ/m²
78
79
54

NII, −30° C.
kJ/m²
75
61
45

Mod. of elasticity
MPa
2113
2117
1986

Tens. strength @
MPa
56
56
51

yld

Tens. strength @
MPa
59
68
59

brk

Tens. elong. @ yld
%
6
6
5

Nominal strain @
%
82
120
110

brk

L*

14.4
18.1
27.7

a*

−0.2
−0.9
−1.7

b*

12.2
−12.9
−9.1

5 days sunscreen
Strain@brk
78
98
109

exposure - run 1
(%)

5 days sunscreen
Strain@brk
80
67
94

exposure - run 2
(%)

5 days sunscreen
Strain@brk
79
107
81

exposure - run 3
(%)

5 days sunscreen
Strain@brk
71
105
Break

exposure - run 4
(%)

5 days sunscreen
Strain@brk
78
17
Break

exposure - run 5
(%)

2 days insect
Strain@brk
80
102
107

repellant
(%)

exposure - run 1

2 days insect
Strain@brk
79
101
95

repellant
(%)

exposure - run 2

2 days insect
Strain@brk
79
99
84

repellant
(%)

exposure - run 3

2 days insect
Strain@brk
74
96
79

repellant
(%)

exposure - run 4

2 days insect
Strain@brk
74
80
15

repellant
(%)

exposure - run 5

2 days insect
Strain@brk
73
62
3.1

repellant
(%)

exposure - run 6

2 days insect
Strain@brk
70

3.1

repellant
(%)

exposure - run 7

2 days insect
Strain@brk
60
41
2.7

repellant
(%)

exposure - run 8

2 days insect
Strain@brk
5
35
2.7

repellant
(%)

exposure - run 9

2 days insect
Strain@brk
Break
31
2.4

repellant
(%)

exposure - run 10

*indicates a comparative example

Table 5 shows that the use of the high molecular weight bisphenol A homopolycarbonate can further provide favorable chemical resistance properties. When PC-3 is used as the main polycarbonate component (Comparative Example 3), multiple fails were observed at 1% strain after exposing the sample to an insect repellant spray for two days. Similarly, exposing the compositions to a sunscreen spray also resulted in early failure in 2 out of 5 samples at 1% strain after exposing the sample for five days. In contrast, homopolycarbonate having higher molecular weights provides improved chemical resistance.

Examples 5-8

Table 7 shows the compositions and properties for the compositions according to Examples 5-8. As can be seen in Table 6, the color (i.e., the L*, at, and b*) values were unexpectedly improved as the molecular weight of the bisphenol A homopolycarbonate component increases when a combination of high molecular weight bisphenol A homopolycarbonates were used. Interestingly, the color of the composition was observed to improve even when high amounts of dyes were included, (e.g., comparing example 2 with example 4, with example 4 exhibiting improved color due to changing the colorants and loading). Notably, the L* value could be decreased to below 10, a “deep black” color, which is typically difficult to achieve. From Table 6, it can be seen that using a polycarbonate component having a molecular weight of, for example, 26,000 g/mol or greater, or 27,000 g/mol or greater, or 28,000 g/mol or greater, can provide a desirable L* value for the polycarbonate composition. The amount of each component is expressed in weight percent based on the total weight of the composition.

TABLE 6

Unit
4
5
6%
7*

Component

PC-2
wt %
83.11
62.36
41.61
20.86

PC-3
wt %

20.75
41.5
62.25

PC-Si
wt %
15
15
15
15

TBPP
wt %
0.09
0.09
0.09
0.09

BZT
wt %
0.3
0.3
0.3
0.3

PETS
wt %
0.1
0.1
0.1
0.1

TSAN
wt %
0.2
0.2
0.2
0.2

SG3
wt %
0.3
0.3
0.3
0.3

SY163
wt %
0.3
0.3
0.3
0.3

SR135
wt %
0.3
0.3
0.3
0.3

KSS
wt %
0.3
0.3
0.3
0.3

Properties

MW of PC
g/mol
30,500
28,100
25,800
23,400

homopolymer fraction

UL94 Rating, 1.5 mm

V0
V0
V0
V0

MVR (2.16 kg/300° C.)
cm³/10 min
6
9
13
18

MV, 100 s⁻¹
Pa-s
778
537
411
324

MV, 200 s⁻¹
Pa-s
663
466
398
318

MV, 500 s⁻¹
Pa-s
499
406
336
276

MV, 1000 s⁻¹
Pa-s
382
306
271
223

MV, 2000 s⁻¹
Pa-s
288
243
215
179

MV, 3500 s⁻¹
Pa-s
205
177
156
133

MV, 5000 s⁻¹
Pa-s
163
145
125
110

MV, 7000 s⁻¹
Pa-s
134
118
104
90

MV, 9000 s^−l
Pa-s

86

Mod. of elasticity
MPa
2116
2107
2084
2074

Tens. strength @ yld
MPa
57
56
55
54

Tens. strength @ brk
MPa
66
64
60
51

Tens. elong. @ yld
%
5
5
5
5

Nominal strain @ brk
%
108
105
98
66

L*

7.1
8.6
11.2
14.2

a*

−2.1
−3.0
−3.2
−3.3

b*

−2.8
−3.3
−3.4
−3.6

Examples 8-9

Table 7 shows the compositions and properties for the compositions according to Examples 8 and 9, comparing different types of PC-Si copolymers (e.g., comparing PC-Si-1 having 20% siloxane and PC-Si-2 having 40% siloxane). The amount of each component is expressed in weight percent based on the total weight of the composition.

TABLE 7

Unit
8*
9

Component

PC-2
wt %
36.72
63.88

PC-3
wt %
36.76
17

PC-Si-1
wt %

15

PC-Si-2

22.2

TBPP
wt %
0.09
0.09

BZT
wt %
0.3
0.3

PETS
wt %
0.3
0.1

TSAN
wt %
0.3
0.3

Yellow Pigment
wt %
0.03
0.03

KSS
wt %
0.3
0.3

TIO2
wt %
3
3

Properties

MVR, 2.16 kg
cm³/10 min
15.6
8.8

MV, 100 s⁻¹
Pa-s
395
582

MV, 200 s⁻¹
Pa-s
341
591

MV, 500 s⁻¹
Pa-s
320
490

MV, 1000 s⁻¹
Pa-s
272
370

MV, 2000 s⁻¹
Pa-s
219
261

MV, 3500 s⁻¹
Pa-s
161
183

MV, 5000 s^−l
Pa-s
130
140

MV, 7000 s⁻¹
Pa-s
105
119

MV, 9000 s⁻¹
Pa-s
85
99

standard - average of 5 runs
Strain@brk
78
80

(%)

3 days caustic soda
Strain@brk
55
80

exposure (5%) - average
(%)

of 5 runs

5 days sun screen
Strain@brk
3.7
76

exposure - average of 5 runs
(%)

2 days insect repellant
Strain@brk
<1.0
82

exposure - average of 5 runs
(%)

1 day gasoline exposure -
Strain@brk
<1.0
28

average of 5 runs
(%)

*indicates a comparative example

Table 7 shows that when PC-Si-2 is used in combination was a homopolycarbonate having a molecular weight of 28,000 g/mol or great, a unique balance of MVR and MV can be achieved. Surprisingly, despite a significantly lower MVR, the MV of the composition is comparable, indicating that the composition of the present disclosure will retain good processability.

Comparative Example 8 is considered to be an excellent injection-moldable grade polycarbonate based on the MVR and the MV at 5000 s⁻¹. However, as shown in Table 7, it does not provide the chemical resistance required for some application. In contrast, in the case of Example 9, the use of a PC-Si copolymer having a higher siloxane content and a higher molecular weight homopolycarbonate can provide a composition that advantageously can meet certain color requirements and chemical resistance requirements. It is noted that at first glance the composition according to Example 9 appears to have a lower flow compared to Comparative Example 8 when looking at MVR alone. However, during processing, the flow of the material is better represented by the MV value at the shear rate of 5000 s⁻¹or higher, where it can be seen that Example 9 only differs by about 10% compared to the viscosity of Comparative Example 8, which would be considered as substantially the same by the skilled person.

Examples 10-13

Table 8 shows the compositions according to examples 10-13 and illustrates the effect of polycarbonate-siloxane content on various properties. It can be seen from Table 8 that increase the PC-Si component decreases the MVR, but that the MV is not significantly affected, indicating good processability (and in case of higher shear, an opposite trend is visible at 5000 s⁻¹versus 100 s⁻¹shear rates, suggesting enhanced processability). The data also shows worsening of color when increasing the amount of PC-Si, but low L* values can still be achieved. Adding the PC-Si-2, for example at a content of 10 to 15% can affect the chemical resistance tests, however, the results indicate that increased amounts of PC-Si can significantly improve chemical resistance.

TABLE 8

Unit
10*
11*
12
13

Component

PC-2
wt %
97.81
92.71
87.91
83.11

PC-Si-1
wt %

5
10
15

TBPP
wt %
0.09
0.09
0.09
0.09

BZT
wt %
0.3
0.3
0.3
0.3

PETS
wt %
0.1
0.1
0.1
0.1

TSAN
wt %
0.5
0.6
0.4
0.2

SG3
wt %
0.3
0.3
0.3
0.3

SY163
wt %
0.3
0.3
0.3
0.3

SR135
wt %
0.3
0.3
0.3
0.3

KSS
wt %
0.3
0.3
0.3
0.3

Properties

UL94 Rating, 1.5 mm

V0
V0
V0
V0

MVR, 2.16 kg
cm³/10 min
11
9
8
7

MV, 100 s⁻¹
Pa-s
591
626
744
787

MV, 200 s⁻¹
Pa-s
627
559
651
697

MV, 500 s⁻¹
Pa-s
549
483
504
528

MV, 1000 s⁻¹
Pa-s
459
380
391
394

MV, 2000 s⁻¹
Pa-s
332
325
311
303

MV, 3500 s⁻¹
Pa-s
234
228
217
211

MV, 5000 s⁻¹
Pa-s
184
180
171
166

MV, 7000 s⁻¹
Pa-s
150
148
139
137

MV, 9000 s⁻¹
Pa-s

121

110.1

Mod. of elasticity
MPa
2415
2306
2218
2126

Tens. strength @ yld
MPa
66
62
59
57

Tens. strength @ brk
MPa
68
68
69
61

Tens. elong. @ yld
%
6
6
6
6

Nominal strain @ brk
%
94
101
114
98

L*

1.432
9.286
9.9
7.338

a*

0.47
2.584
−3.176
−2.14

b*

0.024
−0.888
−2.514
−2.826

Tens. strain @ brk,
%
3.0
4.2
71
107

5 days sunscreen

exposure - run 1

Tens. strain @ brk,
%
3.3
3.7
108
106

5 days sunscreen

exposure - run 2

Tens. strain @ brk,
%
3.6
25
108
109

5 days sunscreen

exposure - run 3

Tens. strain @ brk,
%
3.5
3.7
113
95

5 days sunscreen

exposure - run 4

Tens. strain @ brk,
%
3.5
3.7
93
30

5 days sunscreen

exposure - run 5

This disclosure further encompasses the following aspects.

- Aspect 1: A polycarbonate composition comprising: 80 to 90 weight percent of a bisphenol A homopolycarbonate having a weight average molecular weight of 28,000 g/mol or more, determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards; and 10 to 20 weight percent of a polycarbonate-siloxane copolymer having a siloxane content of 30 to 70 weight percent, based on the total weight of the polycarbonate-siloxane copolymer; wherein the composition comprises less than 5 weight percent of a polycarbonate-siloxane copolymer having a siloxane content of less than 30 weight percent.
- Aspect 2: The polycarbonate composition of aspect 1, wherein the polycarbonate composition has a melt volume rate of less than or equal to 10 cm³/10 minutes, as determined according to ISO1133 under a load of 2.16 kg at 300° C. with a dwell time of 300 seconds.
- Aspect 3: The polycarbonate composition of aspect 1 or 2, wherein the polycarbonate composition has a melt volume rate of less than or equal to 10 cm³/10 minutes, as determined according to ISO1133 under a load of 2.16 kg at 300° C. with a dwell time of 300 seconds, and a melt viscosity of less than or equal to 200 Pas at 5000 s⁻¹shear rate, measured at 300° C., according to ISO 11443.
- Aspect 4: The polycarbonate composition of any of aspects 1 to 3, wherein the bisphenol A homopolycarbonate has a weight average molecular weight of 29,000 to 45,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards.
- Aspect 5: The polycarbonate composition of any of aspects 1 to 4, wherein the bisphenol A homopolycarbonate comprises a first linear bisphenol A homopolycarbonate having a weight average molecular weight of 32,000 to 38,000 grams per mole, preferably 34,000 to 36,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards; or a second linear bisphenol A homopolycarbonate having a weight average molecular weight of 29,000 to 32,000 grams per mole, preferably 30,000 to 31,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards; or a combination thereof.