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EP-4247890-B1 - POLYCARBONATE COMPOSITION, METHOD FOR THE MANUFACTURE THEREOF, AND ARTICLES FORMED THEREFROM

EP4247890B1EP 4247890 B1EP4247890 B1EP 4247890B1EP-4247890-B1

Inventors

  • SANGREGORIO, Anna
  • van der Mee, Mark Adrianus Johannes
  • FARRELL, TONY
  • VOLLENBERG, PETER
  • PATIL, RAHUL

Dates

Publication Date
20260513
Application Date
20211118

Claims (15)

  1. A polycarbonate composition comprising: 10 to 99 weight percent, based on the total weight of the polycarbonate composition, of a bisphenol A polycarbonate homopolymer; a polycarbonate-siloxane copolymer having a siloxane content of greater than 30 to 70 weight percent, preferably 35 to 65 weight percent, based on the total weight of the polycarbonate-siloxane copolymer; wherein the polycarbonate-siloxane copolymer is present in an amount to provide a total siloxane content of 0.5 to 20 weight percent, based on the total weight of the polycarbonate composition; 15 to 45 weight percent of a poly(ester-carbonate); and optionally, 0.5 to 6 weight percent, based on the total weight of the polycarbonate composition, of an organophosphorus flame retardant.
  2. The polycarbonate composition of claim 1, wherein a molded sample of the composition exhibits: a tensile elongation retention of at least 80% after exposure to DOT 4 or DOT 5.1 brake fluid for 72 hours at a temperature of 23°C under 0% strain compared to non-exposed reference sample of the same composition, determined according to ISO 527; and an Izod notched impact strength of greater than 650 kilojoules per meter at a temperature of 23°C, as determined according to ASTM D256-10; and optionally, an Izod notched impact strength of greater than 400 kilojoules per meter at a temperature of -30°C, as determined according to ASTM D256-10.
  3. The polycarbonate of claim 1 or 2, wherein the organophosphorus flame retardant is present, and wherein the polycarbonate composition further exhibits 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.
  4. The polycarbonate composition of any of claims 1 to 3, wherein the bisphenol A polycarbonate homopolymer comprises a linear bisphenol A polycarbonate homopolymer having a weight average molecular weight of 15,000 to 40,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards, preferably wherein the bisphenol A polycarbonate homopolymer comprises a linear bisphenol A polycarbonate homopolymer having a weight average molecular weight of 15,000 to 25,000 grams per mole, preferably 17,000 to 25,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards; or a linear bisphenol A polycarbonate homopolymer having a weight average molecular weight of 26,000 to 40,000 grams per mole, preferably 27,000 to 35,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards; or a combination thereof; more preferably, wherein the bisphenol A polycarbonate homopolymer comprises a linear bisphenol A polycarbonate homopolymer having a weight average molecular weight of 26,000 to 40,000 grams per mole, preferably 27,000 to 35,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards.
  5. The polycarbonate composition of any of claims 1 to 4, wherein the polycarbonate-siloxane copolymer comprises bisphenol A carbonate repeating units and poly(dimethyl siloxane) repeating units.
  6. The polycarbonate composition of any of claims 1 to 5, wherein the polycarbonate-siloxane copolymer has a weight average molecular weight of 17,000 to 50,000 g/mol, or 17,000 to 45,000 g/mol, or 20,000 to 45,000 g/mol, or 30,000 to 45,000 g/mol, or 32,000 to 36,000 g/mol, or 30,000 to 45,000 g/mol, or 32,000 to 45,000 g/mol, or 35,000 to 45,000 g/mol, or 35,000 to 40,000 g/mol, or 32,000 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.
  7. The polycarbonate composition of any of claims 1 to 6, wherein the poly(ester-carbonate) comprises a poly(phthalate-carbonate).
  8. The polycarbonate composition of any of claims 1 to 7, wherein the organophosphorus flame retardant is present and comprises a phosphazene, a phosphate ester, an oligomeric phosphate ester, or a combination thereof, preferably a phosphazene flame retardant, an oligomeric phosphate ester flame retardant, or a combination thereof.
  9. The polycarbonate composition of any of claims 1 to 8, wherein one or more of the bisphenol A homopolymer carbonate, the polycarbonate-siloxane copolymer, and the poly(ester-carbonate) are derived from post-consumer recycled or post-industrial recycled materials or can be produced from at least one monomer derived from bio-based or plastic waste feedstock.
  10. The polycarbonate composition of any of claims 1 to 9, wherein the polycarbonate composition further comprises 0.1 to 10 weight percent, based on the total weight of the polycarbonate composition, of an additive composition, preferably comprising an anti-drip agent.
  11. The polycarbonate composition of any of claims 1 to 10, wherein the polycarbonate composition further comprises 0.001 to 10 weight percent of an antimicrobial agent, preferably wherein the antimicrobial agent comprises a silver-containing agent.
  12. The polycarbonate composition of any of claims 1 to 11, comprising 25 to 75 weight percent of the bisphenol A polycarbonate homopolymer; 5 to 20 weight percent of the polycarbonate-siloxane copolymer; and 20 to 60 weight percent of the poly(ester carbonate); or 40 to 90 weight percent of the bisphenol A polycarbonate homopolymer; 5 to 15 weight percent of the polycarbonate-siloxane copolymer; 20 to 40 weight percent of the poly(ester carbonate); and 1 to 6 weight percent of the organophosphorus flame retardant.
  13. The polycarbonate composition of claim 12, wherein the bisphenol A polycarbonate homopolymer comprises a linear bisphenol A polycarbonate homopolymer having a weight average molecular weight of 26,000 to 40,000 grams per mole, preferably 27,000 to 35,000 grams per mole, as determined by gel permeation chromatography relative to linear bisphenol A polycarbonate standards; the polycarbonate-siloxane copolymer comprises bisphenol A carbonate repeating units and poly(dimethyl siloxane) repeating units; the polycarbonate-siloxane copolymer has a siloxane content of 35 to 65 weight percent based on the total weight of the polycarbonate-siloxane copolymer; the poly(ester-carbonate) comprises a poly(phthalate-carbonate); and when present, the organophosphorus flame retardant comprises a cyclic phosphazene, preferably hexaphenoxycyclotriphosphazene, or an oligomeric phosphate ester flame retardant comprising 5 to 15 weight percent phosphorus, based on the total weight of the oligomeric phosphate ester, preferably wherein the oligomeric phosphate ester is a solid at room temperature; wherein a molded sample of the polycarbonate composition exhibits: a tensile elongation retention of at least 80% after exposure to DOT 4 or DOT 5.1 brake fluid for 72 hours at a temperature of 23°C under 0% strain compared to non-exposed reference sample of the same composition, determined according to ISO 527; an Izod notched impact strength of greater than 650 joules per meter at a temperature of 23°C, as determined according to ASTM D256-10; an Izod notched impact strength of greater than 400 joules per meter at a temperature of -30°C, as determined according to ASTM D256-10; and when the organophosphorus flame retardant is present, 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.
  14. A method of making the polycarbonate composition of any of claims 1 to 13, the method comprising melt-mixing the components of the composition, and, optionally, extruding the composition.
  15. An article comprising the polycarbonate composition of any of claims 1 to 13.

Description

BACKGROUND Polycarbonate homopolymers and polycarbonate copolymers are useful in a wide variety of applications at least in part because of their good balance of properties, such as moldability, heat resistance and impact properties, among others. Despite extensive research on these materials over the years, there still remains a need in the art for improved polycarbonate compositions that meet increasingly stringent industry standards. For example, polycarbonate-polysiloxane copolymers can have good mechanical properties and low temperature impact resistance. However, chemical resistance can be difficult to achieve. There is also a need for compositions that can further exhibit good flame retardance without sacrificing chemical resistance and impact properties. Achieving this balance of properties, especially in the absence of halogenated flame retardants, is challenging. US 2014/326162 A1 discloses a thermoplastic polymer composition comprising a specific polycarbonate, a poly(carbonate-siloxane) and an organophosphorus compound. US 2014/179843 A1 discloses a composition comprising a first polycarbonate and a second polymer different from the first polycarbonate, the second polymer comprising a poly(carbonate-siloxane) copolymer, a polydialkylsiloxane, or a combination thereof. EP 3712209A1 discloses a thermoplastic composition comprising a thermoplastic component comprising polybutylene terephthalate and a second thermoplastic polymer consisting of polycarbonate or polyethylene terephthalate; a component comprising a polyester elastomer, an ethylene/alkyl acrylate/glycidyl methacrylate terpolymer compatibilizer, or a combination thereof; and a ceramic fiber component including ceramic fibers. US 2014/179821 A1 discloses a polymeric blend comprising a photoactive additive containing a photoactive group derived from a monofunctional benzophenone; and a polymer resin selected from a polyester, a polysiloxane-co-bisphenol-A polycarbonate, a polyesteramide, a polyimide, a polyetherimide, a polyamideimide, a polyether, a polyethersulfone, a polyepoxide, a polylactide, a polylactic acid, or any combination thereof. WO 2020/079565 A1 discloses a composite including a fibrous material, and a thermoplastic matrix comprising a thermoplastic composition including a polyester; a phosphorus-containing flame retardant; and a polycarbonate. WO 2019/123029 A1 discloses a polycarbonate composition including a bisphenol A polycarbonate homopolymer; and a poly(carbonate- siloxane) polymer. There accordingly remains a need in the art for polycarbonate compositions that can have balanced mechanical properties including low temperature impact, chemical resistance, and flame retardance. SUMMARY A polycarbonate composition comprises 10 to 99 weight percent, based on the total weight of the polycarbonate composition, of a bisphenol A polycarbonate homopolymer; a polycarbonate-siloxane copolymer having a siloxane content of greater than 30 to 70 weight percent, preferably 35 to 65 weight percent, based on the total weight of the polycarbonate-siloxane copolymer; wherein the polycarbonate-siloxane copolymer is present in an amount to provide a total siloxane content of 0.5 to 20 weight percent, based on the total weight of the polycarbonate composition; 15 to 45 weight percent of a poly(ester-carbonate); and optionally, 0.5 to 6 weight percent, based on the total weight of the polycarbonate composition, of an organophosphorus flame retardant. A method of making the polycarbonate composition comprises melt-mixing the components of the composition, and, optionally, extruding the composition. An article comprises the polycarbonate composition. The above described and other features are exemplified by the following detailed description. DETAILED DESCRIPTION Provided herein are polycarbonate compositions having a desirable combination of properties, including impact strength, chemical resistance, and, when a particular flame retardant is included in the composition, flame retardance. The present inventors have determined that such properties can be obtained with a polycarbonate composition including particular amounts of a bisphenol A polycarbonate homopolymer, a polycarbonate-siloxane copolymer having a siloxane content of greater than 30 to 70 weight percent, a poly(ester-carbonate), and optionally, an organophosphorus flame retardant. Accordingly, an aspect is a polycarbonate composition. The polycarbonate composition comprises a bisphenol A polycarbonate homopolymer, also referred to as a bisphenol A homopolycarbonate. The bisphenol A polycarbonate homopolymer has repeating structural carbonate units of the formula (1). Bisphenol A polycarbonate homopolymers can be manufactured by processes such as interfacial polymerization and melt polymerization, which are known, and are described, for example, in WO 2013/175448 A1 and WO 2014/072923 A1, from bisphenol A ((2,2-bis(4-hydroxyphenyl)propane, or BPA). An endcapping agent can be incl