Polyetherimide composition and associated article and additive manufacturing method
A polyetherimide composition includes specific amounts of a polyetherimide, a block polyestercarbonate, a block poly-carbonate-polysiloxane, and a core-shell impact modifier in which the core includes a polysiloxane and the shell includes a poly(alkyl (meth)acrylate). Relative to a corresponding composition lacking the core-shell impact modifier, the polyetherimide composition exhibits increased impact strength while substantially retaining flame retardancy. Also described are associated articles, including articles formed by additive manufacturing, and a method of additive manufacturing.
1. A composition comprising, based on the total weight of the composition:
40 to 60 weight percent of a polyetherimide;
15 to 50 weight percent of a block polyestercarbonate comprising
a polyester block comprising resorcinol ester repeat units having the structure
and
a polycarbonate block comprising carbonate repeat units having the structure
wherein at least 60 percent of the total number of R 1 groups are aromatic;
5 to 15 weight percent of a block polycarbonate-polysiloxane; and
1.5 to 7 weight percent of a core-shell impact modifier comprising, based on the weight of the core-shell impact modifier,
60 to 95 weight percent of a core comprising a polysiloxane, and
5 to 40 weight percent of a shell comprising a poly(alkyl (meth)acrylate);
wherein the composition comprises 0 to 0.8 weight percent of polystyrene-poly(ethylene-butylene)-polystyrene block copolymers.
2. The composition of claim 1 , wherein the polysiloxane comprises polydimethylsiloxane.
3. The composition of claim 1 , wherein the poly(alkyl (meth)acrylate) comprises poly(methyl methacrylate).
4. The composition of claim 1 , wherein the core-shell impact modifier comprises, based on the weight of the core-shell impact modifier, 65 to 85 weight percent of the core and 15 to 35 weight percent of the shell.
5. The composition of claim 1 , comprising 15 to 30 weight percent of the block polyestercarbonate, and further comprising 10 to 30 weight percent of a block polyestercarbonate-polysiloxane, wherein the block polyestercarbonate-polysiloxane comprises
a polyester block comprising resorcinol ester repeat units having the structure
a polycarbonate block comprising carbonate repeat units having the structure
wherein at least 60 percent of the total number of R 1 groups are aromatic, and
a polysiloxane block comprising dimethylsiloxane repeat units.
6. The composition of claim 1 , further comprising 1 to 10 weight percent of a block polyetherimide-polysiloxane.
7. The composition of claim 1 , comprising 0 to 1 weight percent of phosphazene flame retardants.
8. The composition of claim 1 , excluding organophosphate esters, metal dialkylphosphinates, phosphazenes, melamine-based flame retardants, and metal hydroxides.
9. The composition of claim 1 ,
comprising
45 to 55 weight percent of the polyetherimide,
15 to 30 weight percent of the block polyestercarbonate,
6 to 12 weight percent of the block polycarbonate-polysiloxane, and
2 to 6 weight percent of the core-shell impact modifier; and
further comprising
10 to 30 weight percent of a block polyestercarbonate-polysiloxane, wherein the block polyestercarbonate-polysiloxane comprises
a polyester block comprising resorcinol ester repeat units having the structure
a polycarbonate block comprising carbonate repeat units having the structure
wherein at least 60 percent of the total number of R 1 groups are aromatic, and
a polysiloxane block comprising dimethylsiloxane repeat units.
10. The composition of claim 9 , wherein
the polyetherimide comprises poly(2,2′-bis(4-(3,4-dicarboxyphenoxy)phenylpropane)-1,3-phenylene bisimide),
at least 90 percent of the total number of R 1 groups of the polycarbonate block(s) of the block polyestercarbonate are 1,3-phenylene or 2,2-bis(1,4-phenylene)propane,
at least 90 percent of the total number of R 1 groups of the polycarbonate block(s) of the block polycarbonate-polysiloxane are 1,3-phenylene or 2,2-bis(1,4-phenylene)propane,
at least 90 percent of the total number of R 1 groups of the polycarbonate block(s) of the block polyestercarbonate-polysiloxane are 1,3-phenylene or 2,2-bis(1,4-phenylene)propane,
the polysiloxane block(s) of the block polycarbonate-polysiloxane and the block polyestercarbonate-polysiloxane comprise polydimethylsiloxane, and
the poly(alkyl (meth)acrylate) of the core-shell impact modifier comprises poly(methyl methacrylate).
11. An article comprising a composition comprising, based on the total weight of the composition:
40 to 60 weight percent of a polyetherimide;
15 to 50 weight percent of a block polyestercarbonate comprising
a polyester block comprising resorcinol ester repeat units having the structure
and
a polycarbonate block comprising carbonate repeat units having the structure
wherein at least 60 percent of the total number of R 1 groups are aromatic;
5 to 15 weight percent of a block polycarbonate-polysiloxane; and
1.5 to 7 weight percent of a core-shell impact modifier comprising, based on the weight of the core-shell impact modifier,
60 to 95 weight percent of a core comprising a polysiloxane, and
5 to 40 weight percent of a shell comprising a poly(alkyl (meth)acrylate);
wherein the composition comprises 0 to 0.8 weight percent of polystyrene-poly(ethylene-butylene)-polystyrene block copolymers.
12. The article of claim 11 , wherein the article is a filament having a diameter of 1 to 5 millimeters.
13. The article of claim 11 , comprising at least two adjacent layers comprising the composition.
14. The article of claim 13 , characterized by mutually orthogonal x, y, and z dimensions, the x, y, and z dimensions independently being 0.5 millimeter to 50 centimeters.
15. A method of additive manufacturing, the method comprising:
melt extruding a molten composition to form a plurality of adjacent layers in a predetermined pattern;
wherein the molten composition is characterized by a glass transition temperature;
wherein the molten composition has a temperature 5 to 250° C. greater than the glass transition temperature of the molten composition; and
wherein the molten composition comprises, based on the total weight of the composition,
40 to 60 weight percent of a polyetherimide;
15 to 50 weight percent of a block polyestercarbonate comprising
a polyester block comprising resorcinol ester repeat units having the structure
and
a polycarbonate block comprising carbonate repeat units having the structure
wherein at least 60 percent of the total number of R 1 groups are aromatic;
5 to 15 weight percent of a block polycarbonate-polysiloxane; and
1.5 to 7 weight percent of a core-shell impact modifier comprising, based on the weight of the core-shell impact modifier,
60 to 95 weight percent of a core comprising a polysiloxane, and
5 to 40 weight percent of a shell comprising a poly(alkyl (meth)acrylate);
wherein the composition comprises 0 to 0.8 weight percent of polystyrene-poly(ethylene-butylene)-polystyrene block copolymers.
16. The method of claim 15 ,
wherein the melt extruding comprises melt extruding the molten composition through a nozzle having an internal diameter of 0.2 to 5 millimeters; and
wherein the method further comprises forming the molten composition by heating a filament comprising the composition from a temperature at least 20° C. below the glass transition temperature to the temperature 5 to 50° C. greater than the glass transition temperature; and
wherein the filament has a diameter of 1 to 5 millimeters.
17. The composition of claim 2 , wherein the poly(alkyl (meth)acrylate) comprises poly(methyl methacrylate).
18. The composition of claim 2 , wherein the core-shell impact modifier comprises, based on the weight of the core-shell impact modifier, 65 to 85 weight percent of the core and 15 to 35 weight percent of the shell.
19. The composition of claim 3 , wherein the core-shell impact modifier comprises, based on the weight of the core-shell impact modifier, 65 to 85 weight percent of the core and 15 to 35 weight percent of the shell.
20. The composition of claim 4 , comprising 15 to 30 weight percent of the block polyestercarbonate, and further comprising 10 to 30 weight percent of a block polyestercarbonate-polysiloxane, wherein the block polyestercarbonate-polysiloxane comprises
a polyester block comprising resorcinol ester repeat units having the structure
a polycarbonate block comprising carbonate repeat units having the structure
wherein at least 60 percent of the total number of R 1 groups are aromatic, and
a polysiloxane block comprising dimethylsiloxane repeat units.