Flame retardant thermoplastic polycarbonate compositions
View Patent ↗Polycarbonate compositions are disclosed. The compositions comprise an optional polycarbonate polymer (A); a polycarbonate-polysiloxane copolymer (B); a phosphorous-containing flame retardant (C); and a reinforcing agent (D). The resulting compositions have an improved combination of properties, particularly Vicat softening temperature and high flame retardance in thin walls.
1. A flame retardant thermoplastic composition, comprising:
a polysiloxane-polycarbonate copolymer;
an optional polycarbonate polymer;
from 1 to 2 weight percent of a phosphorous-containing flame retardant; and
from about 0.01 to 25 weight percent of a filler comprising glass or talc;
wherein the thermoplastic composition has a Vicat B50 softening temperature of at least 120° C. when measured according to ISO 306 and a heat deflection temperature of at least 120° C. when measured according to ISO 75;
wherein an article molded from the thermoplastic composition can attain UL94 V0 performance at a thickness of 1.2 mm.
2. The thermoplastic composition of claim 1 , wherein the polycarbonate polymer is a bisphenol-A homopolymer.
3. The thermoplastic composition of claim 1 , wherein the phosphorous-containing flame retardant is bisphenol-A bis(diphenylphosphate).
4. The thermoplastic composition of claim 1 , wherein the thermoplastic composition comprises from about 0.5 to about 6 weight percent of siloxane originating from the polysiloxane-polycarbonate copolymer.
5. The thermoplastic composition of claim 1 , wherein the thermoplastic composition comprises from about 1.2 to about 6 weight percent of siloxane originating from the polysiloxane-polycarbonate copolymer.
6. The thermoplastic composition of claim 1 , wherein the thermoplastic composition comprises at least 0.09 weight percent of phosphorous originating from the phosphorous-containing flame retardant.
7. The thermoplastic composition of claim 1 , wherein the thermoplastic composition does not contain additional impact modifier.
8. The thermoplastic composition of claim 1 , wherein an article molded from the thermoplastic composition can attain UL94 V0 performance at a thickness of 1.0 mm.
9. The thermoplastic composition of claim 1 , wherein the composition has a notched Izod impact strength of 12 kJ/m 2 or greater, when measured according to ISO 180.
10. The thermoplastic composition of claim 1 , wherein the thermoplastic composition comprises at least 1.5 weight percent of the bisphenol-A bis(diphenylphosphate).
11. The thermoplastic composition of claim 1 , wherein the thermoplastic composition comprises from about 0.01 to 10 weight percent of the filler, and the filler is glass.
12. The thermoplastic composition of claim 1 , wherein the thermoplastic composition has a Vicat B50 softening temperature of at least 130° C. when measured according to ISO 306.
13. The thermoplastic composition of claim 12 , wherein the thermoplastic composition has a notched Izod impact strength of 15 kJ/m 2 or greater, when measured according to ISO 180.
14. A flame retardant thermoplastic composition, comprising:
a polysiloxane-polycarbonate copolymer;
an optional polycarbonate polymer;
from 1 to 2 weight percent of a phosphorous-containing flame retardant; and
a reinforcing agent;
wherein the thermoplastic composition has a Vicat B50 softening temperature of at least 120° C. when measured according to ISO 306 and a heat deflection temperature of at least 120° C. when measured according to ISO 75; and
wherein an article molded from the thermoplastic composition can attain UL94 V0 performance at a thickness of 1.2 mm.
15. The thermoplastic composition of claim 14 , wherein the composition comprises from about 0.01 to 10 weight percent of the reinforcing agent.
16. A flame retardant thermoplastic composition, comprising:
a polysiloxane-polycarbonate copolymer;
a polycarbonate polymer;
from 1 to 2 weight percent of a phosphorous-containing flame retardant; and
from about 0.01 to 25 weight percent of a filler comprising glass or talc;
wherein the thermoplastic composition has a Vicat B50 softening temperature of at least 120° C. when measured according to ISO 306 and a heat deflection temperature of at least 120° C. when measured according to ISO 75; and
wherein an article molded from the thermoplastic composition can attain UL94 V0 performance at a thickness of 1.2 mm.
17. The thermoplastic composition of claim 16 , wherein the thermoplastic composition has a notched Izod impact strength of 15 kJ/m 2 or greater, when measured according to ISO 180.
18. A flame retardant thermoplastic composition, comprising:
a polysiloxane-polycarbonate copolymer;
a polycarbonate polymer;
from 0.75 to 2 weight percent of a phosphorous-containing flame retardant; and
a filler comprising glass or talc;
wherein the thermoplastic composition comprises from about 1.2 to about 6 weight percent of siloxane originating from the polysiloxane-polycarbonate copolymer;
wherein the thermoplastic composition has a Vicat B50 softening temperature of at least 120° C. when measured according to ISO 306 and and a heat deflection temperature of at least 120° C. when measured according to ISO 75; and
wherein an article molded from the thermoplastic composition can attain UL94 V0 performance at a thickness of 1.5 mm.