Thermosetting polymer formulations, circuit materials, and methods of use thereof
View Patent ↗A thermosetting polymer formulation includes: 40 to 90 volume percent of a thermosetting polymer system; 10 to 40 volume percent, preferably 20 to 35 volume percent, preferably 20 to 30 volume percent, of a plurality of hexagonal boron nitride platelets having a mean particle diameter of 5 to 20 micrometers, preferably 8 to 15 micrometers, and a D10 particle diameter of 3 to 7 micrometers, preferably 3 to 5 micrometers, and a D90 particle diameter of 20 to 30 micrometers, preferably 25 to 30 micrometers; a total of 0.01 to 10 volume percent of a coupling agent, an impact modifier, a curing agent, a defoamer, a colorant, a thickening agent, a release agent, an accelerator, or a combination comprising at least one of the foregoing, wherein the volume percentages are based on the total volume of the formulation.
1. A thermosetting polymer formulation, comprising:
40 to 90 volume percent of a thermosetting polymer system;
10 to 40 volume percent of a plurality of hexagonal boron nitride platelets having a mean particle diameter of 5 to 20 micrometers, and a D10 particle diameter of 3 to 7 micrometers, and a D90 particle diameter of 20 to 30 micrometers;
a total of 0.01 to 10 volume percent of a coupling agent, an impact modifier, a curing agent, a defoamer, a colorant, a thickening agent, a release agent, an accelerator, or a combination comprising at least one of the foregoing.
2. The formulation of claim 1 , comprising more than 60 volume percent of the thermosetting polymer system.
3. The formulation of claim 1 , wherein the thermosetting polymer system comprises a butadiene, an isoprene, a bis-maleimide, a styrene-maleic anhydride copolymer, an epoxy, a polyurethane prepolymer composition, a cyanate ester, a styrene butadiene copolymer, a benzoxazine, or a combination comprising at least one of the foregoing.
4. The formulation of claim 1 , wherein the thermosetting polymer system is a thermosetting epoxy system comprising
15 to 85 volume percent of a liquid epoxy resin component; and
15 to 60 volume percent of a phenolic curing system.
5. The formulation of claim 1 , comprising
35 to 45 volume percent of an epoxy resin component;
18 to 26 volume percent of a curing system;
25 to 40 volume percent of a plurality of hexagonal boron nitride platelets;
1 to 5 volume percent of an impact modifier;
0.5 to 1.5 volume percent of a curing agent;
0.2 to 0.9 volume percent of an accelerator; and
0.2 to 0.6 volume percent of a coupling agent, wherein the volume percentages are based on the total volume of the formulation.
6. The thermosetting polymer formulation of claim 1 , comprising:
20 to 35 volume percent of the plurality of hexagonal boron nitride platelets.
7. The thermosetting polymer formulation of claim 1 , comprising:
20 to 30 volume percent of the plurality of hexagonal boron nitride platelets.
8. The thermosetting polymer formulation of claim 1 , wherein the plurality of hexagonal boron nitride platelets has a mean particle diameter of 8 to 15 micrometers.
9. The thermosetting polymer formulation of claim 1 , wherein the plurality of hexagonal boron nitride platelets has a D10 particle diameter of 3 to 5 micrometers.
10. The thermosetting polymer formulation of claim 1 , wherein the plurality of hexagonal boron nitride platelets has a D90 particle diameter of 25 to 30 micrometers.
11. A dielectric layer for the manufacture of a dielectric substrate, the dielectric layer comprising:
a thermosetting polymer system; and
10 to 40 volume percent, based on the total volume of the dielectric layer, of a plurality of hexagonal boron nitride platelets having a mean particle diameter of 5 to 20 micrometers, and a D10 particle diameter of 3 to 7 micrometers, and a D90 particle diameter of 20 to 30 micrometers;
wherein after full cure of the dielectric layer, the dielectric layer has
a dielectric constant of less than or equal to 4.5, measured over 1 MHz to 100 GHz;
an in-plane thermal conductivity of greater than 0.5 Watts/meter·Kelvin;
a z-axis thermal conductivity of 0.5 to 1.5 Watts/meter·Kelvin; and
a thickness of less than or equal to 3.0 mils.
12. The dielectric layer of claim 11 , wherein the dielectric layer is halogen-free or wherein the fully cured dielectric layer has a UL rating of V-0.
13. The dielectric layer of claim 11 , wherein the thermosetting polymer system comprises a butadiene, an isoprene, a bis-maleimide, a styrene-maleic anhydride copolymer, an epoxy, a polyurethane prepolymer composition, a cyanate ester, a styrene butadiene copolymer, a benzoxazine, or a combination comprising at least one of the foregoing.
14. The dielectric layer of claim 11 , wherein the thermosetting polymer system is a thermosetting epoxy system comprising,
40 to 99 volume percent of an epoxy resin component; and
15 to 60 volume percent of a curing system.
15. The dielectric layer of claim 11 , wherein the thermosetting polymer system comprises a liquid epoxy resin and a phenolic curing system.
16. The dielectric layer of claim 11 , further comprising a total of 0.01 to 10 volume percent of a coupling agent, an impact modifier, a curing agent, a defoamer, a colorant, a thickening agent, a release agent, an accelerator, or a combination comprising at least one of the foregoing.
17. The dielectric layer of claim 11 , wherein the thermosetting polymer composition is partially cured or fully cured.
18. A circuit subassembly, comprising an electrically conductive layer disposed on the dielectric layer of claim 11 .
19. The circuit subassembly of claim 18 , wherein the conductive layer comprises copper, or wherein the conductive layer is in the form of a patterned circuit.
20. A method of manufacture of a circuit subassembly, comprising disposing the dielectric layer of claim 11 onto a conductive layer; and partially or fully curing the dielectric layer.
21. The dielectric layer of claim 11 , wherein after full cure of the dielectric layer, the dielectric layer has a dielectric constant of less than or equal to 4.0, measured over 1 MHz to 100 GHz;
an in-plane thermal conductivity of greater than 2.0 Watts/meter-Kelvin; and
a thickness of less than or equal to 2.5 mils.
22. The dielectric layer of claim 11 , wherein after full cure of the dielectric layer, the dielectric layer has a thickness of less than or equal to 2.2 mils.
23. The dielectric layer of claim 11 , wherein after full cure of the dielectric layer, the dielectric layer has a thickness of less than or equal to 2.0 mils.
24. The dielectric layer of claim 11 , wherein after full cure of the dielectric layer, the dielectric layer has a thickness of 0.1 to 2.0 mils.
25. A bond ply for a circuit subassembly comprising:
a first outer layer comprising a thermosetting polymer formulation;
a second outer layer comprising a thermosetting polymer formulation that is of the same type as that of the first outer layer; and
an intermediate layer disposed between the first and the second outer layers, and comprising a thermosetting polymer formulation that is of the same type as the first and second outer layers;
wherein the thermosetting polymer formulation comprises:
40 to 90 volume percent of a thermosetting polymer system;
10 to 40 volume percent, based on the total volume of the dielectric layer, of a plurality of hexagonal boron nitride platelets having a mean particle diameter of 5 to 20 micrometers, and a D10 particle diameter of 3 to 7 micrometers, and a D90 particle diameter of 20 to 30 micrometers;
a total of 0.01 to 10 volume percent of a coupling agent, an impact modifier, a curing agent, a defoamer, a colorant, a thickening agent, a release agent, an accelerator, or a combination comprising at least one of the foregoing;
wherein the thermosetting polymer formulation of the intermediate layer has a degree of cure that is different than a degree of cure for each of the thermosetting polymer formulations of the first and the second outer layers.
26. A circuit comprising the circuit subassembly of claim 25 .
27. A multilayer circuit comprising the circuit subassembly of claim 25 .
28. A handheld device comprising either the circuit of claim 25 .
29. A handheld device comprising the multilayer circuit of claim 27 .
30. The bond ply of claim 25 , comprising:
20 to 35 volume percent of the plurality of hexagonal boron nitride platelets.
31. The bond ply of claim 25 , comprising:
20 to 30 volume percent of the plurality of hexagonal boron nitride platelets.
32. The bond ply of claim 25 , wherein the plurality of hexagonal boron nitride platelets has a mean particle diameter of 8 to 15 micrometers.
33. The bond ply of claim 25 , wherein the plurality of hexagonal boron nitride platelets has a D10 particle diameter of 3 to 5 micrometers.
34. The bond ply of claim 25 , wherein the plurality of hexagonal boron nitride platelets has a D90 particle diameter of 25 to 30 micrometers.