Flame retardant compositions, articles comprising the same and methods of manufacture thereof
Disclosed herein is a flame retardant composition comprising a polycarbonate; a polylactide; and a flame retardant; where the flame retardant is a phenoxyphosphazene, a di- or polyfunctional aromatic phosphorus-containing compound, or a combination comprising at least one of the foregoing flame retardants. Disclosed herein is a method comprising blending a polycarbonate, a polylactide and a flame retardant to form a flame retardant composition; where the flame retardant is a phenoxyphosphazene, a di- or polyfunctional aromatic phosphorus-containing compound, or a combination comprising at least one of the foregoing flame retardants.
1. A flame retardant composition comprising:
a polycarbonate;
a polylactide; and
a flame retardant; where the flame retardant is a phosphazene compound, a di- or polyfunctional aromatic phosphorus-containing compound, or a combination comprising at least one of the foregoing flame retardants; where the polycarbonate comprises a first polycarbonate homopolymer and a second polycarbonate homopolymer; where first polycarbonate homopolymer has a weight average molecular weight of 15,000 to 25,000 Daltons and is present in an amount of 15 to 55 wt %, based on the total weight of the flame retardant composition; and where the second polycarbonate homopolymer has a weight average molecular weight of 25,000 to 40,000 Daltons and is present in an amount of 15 to 55 wt %, based on the total weight of the flame retardant composition.
2. The flame retardant composition of claim 1 , where the polycarbonate comprises bisphenol A carbonate units and is present in an amount of 30 to 90 wt % based on a total weight of the flame retardant composition.
3. The flame retardant composition of claim 1 , where the polycarbonate is branched and is present in an amount of 30 wt % to 80 wt %, based on a total weight of the flame retardant composition.
4. The flame retardant composition of claim 1 , where the phosphazene compound is present in an amount of 1 to 20 wt %, based on a total weight of the flame retardant composition.
5. The composition of claim 1 , where the phosphazene compound has the structure of formula (21)
where in the formula (21), m represents an integer of 3 to 25, R 1 and R 2 are the same or different and are independently a hydrogen, a hydroxyl, a C 7-30 aryl group, a C 1-12 alkoxy, or a C 1-12 alkyl.
6. The composition of claim 1 , where the phosphazene compound is phenoxy cyclotriphosphazene, octaphenoxy cyclotetraphosphazene, decaphenoxy cyclopentaphosphazene, or a combination comprising at least one of the foregoing phosphazene compounds.
7. The composition of claim 1 , where the phosphazene compound has the structure of formula (22)
where in the formula (22), X 1 represents a —N═P(OPh) 3 group or a —N═P(O)OPh group, Y 1 represents a —P(OPh) 4 group or a —P(O)(OPh) 2 group, n represents an integer from 3 to 10000, Ph represents a phenyl group, R 1 and R 2 are the same or different and are independently a hydrogen, a hydroxyl, a C 1-12 alkoxy, or a C 1-12 alkyl.
8. The composition of claim 1 , where the phosphazene compound is a crosslinked phenoxyphosphazene.
9. The composition of claim 1 , where the phosphazene compound is a phenoxyphosphazene.
10. The composition of claim 1 , where the phosphazene compound has a structure represented by the formula (24)
where R 1 to R 6 can be the same of different and can be an aryl group, an aralkyl group, a C 1-12 alkoxy, a C 1-12 alkyl, or a combination thereof.
11. The composition of claim 1 , where the phosphazene compound has a structure represented by the formula (25)
12. The composition of claim 1 , where the flame retardant composition further comprises an anti-drip agent.
13. The composition of claim 1 , where the composition has a flame retardancy of V-0 at a thickness of 2.5 millimeter or lower when measured as per a UL-94 protocol.
14. The composition of claim 1 , where the composition has a flame retardancy of V-0 at a thickness of 2.0 millimeter or lower when measured as per a UL-94 protocol.
15. The composition of claim 1 , where the polylactide is a derived from the polymerization of L-lactic acid and/or from the polymerization of D-lactic acid.
16. The composition of claim 1 , where the polylactide is present in an amount of 5 to 50 wt %, based on the total weight of the flame retardant composition.
17. The composition of claim 1 , where the polylactide is present in an amount of 8 to 20 wt %, based on the total weight of the flame retardant composition.
18. The composition of claim 1 , where the aromatic phosphorus-containing compound is resorcinol di-phosphate or bisphenol A di-phosphate.
19. The composition of claim 1 , where the flame retardant composition comprises up to 25 wt % of an impact modifier, based on the total weight of the flame retardant composition.
20. The composition of claim 1 , where the composition has a flame retardancy of V-0 at a thickness of less than or equal to 3.0 mm when measured as per UL-94 and a notched Izod impact strength of greater than or equal to 200 joules per meter when measured as per ASTM D 256.
21. The composition of claim 1 , where the composition has a flame retardancy of V-0 at a thickness of less than or equal to 1.5 mm when measured as per UL-94 and a notched Izod impact strength of greater than or equal to 90 joules per meter when measured as per ASTM D 256.
22. A method comprising:
combining a polycarbonate, a polylactide, and a flame retardant to form a flame retardant composition; where the flame retardant is a phosphazene, a di- or polyfunctional aromatic phosphorus-containing compound, or a combination comprising at least one of the foregoing flame retardants; where the polycarbonate comprises a first polycarbonate homopolymer and a second polycarbonate homopolymer; where first polycarbonate homopolymer has a molecular weight of 15,000 to 25,000 Daltons and is present in an amount of 15 to 55 wt %, based on the total weight of the flame retardant composition; and where the second polycarbonate homopolymer has a weight average molecular weight of 25,000 to 40,000 Daltons and is present in an amount of 15 to 55 wt %, based on the total weight of the flame retardant composition.
23. The method of claim 22 , further comprising combining an impact modifier.
24. The method of claim 22 , further comprising combining an antidrip agent.
25. The method of claim 22 , further comprising molding the flame retardant composition.
26. A flame retardant composition comprising:
a polycarbonate;
a polylactide; and
a flame retardant; where the flame retardant is a phosphazene compound has a structure represented by the formula (25)
27. The flame retardant composition of claim 26 , where the polycarbonate comprises bisphenol A carbonate units and is present in an amount of 30 to 90 wt % based on a total weight of the flame retardant composition.
28. The flame retardant composition of claim 26 , where the polycarbonate comprises a first polycarbonate homopolymer and a second polycarbonate homopolymer; where first polycarbonate homopolymer has a molecular weight of 15,000 to 25,000 Daltons and is present in an amount of 15 to 55 wt %, based on the total weight of the flame retardant composition; and where the second polycarbonate homopolymer has a molecular weight of 25,000 to 40,000 Daltons and is present in an amount of 15 to 55 wt %, based on the total weight of the flame retardant composition.
29. The flame retardant composition of claim 26 , where the phosphazene compound is present in an amount of 1 to 20 wt %, based on a total weight of the flame retardant composition.
30. The composition of claim 26 , where the polylactide is a derived from the polymerization of L-lactic acid and/or from the polymerization of D-lactic acid.
31. The composition of claim 26 , where the polylactide is present in an amount of 5 to 50 wt %, based on the total weight of the flame retardant composition.
32. An article comprising the composition of claim 26 .