Polymeric compositions with high dielectric constant and low dielectric loss
Disclosed herein are polymeric compositions with low dielectric loss while maintaining high dielectric constant. The composition includes: a) at least one thermoplastic polymer; and b) graphite flakes that are coated with silica coating particles, wherein, the coated graphite flakes have a weight ratio of C:Si ranging from about 10:1-4:1, and the silica coating particles have an average diameter of about 80-400 nm.
1. A polymeric composition comprising: a) at least one thermoplastic polymer; and b) 2 to 30 wt % graphite flakes that are coated with silica coating particles, with the total weight of the composition totaling to 100 wt %, wherein, the coated graphite flakes have a weight ratio of C:Si ranging from 10:1 to 4:1, and the silica coating particles have an average diameter of 80 to 400 nm, wherein the at least one thermoplastic polymer comprises a polyamide.
2. The polymeric composition of claim 1 , wherein the at least one thermoplastic polymer is present at a level of 30 to 96 wt %, based on the total weight of the polymeric composition.
3. The polymeric composition of claim 1 , wherein the coated graphite flakes are present at a level of 3 to 30 wt %, based on the total weight of the polymeric composition.
4. The polymeric composition of claim 1 , wherein the silica coating particles have an average diameter of 85 to 350 nm.
5. The polymeric composition of claim 1 , wherein the coated graphite flakes have a weight ratio of C:Si ranging from 9.5:1 to 4:1.
6. An article formed of the polymeric composition of claim 1 .
7. The article of claim 6 , which is part of an electronic device.
8. The polymeric composition of claim 1 , wherein the at least one thermoplastic polymer is a mixture of two or more polyamides.
9. The polymeric composition of claim 1 , wherein the polyamide is polyamide 6,6.
10. The polymeric composition of claim 2 , wherein the at least one thermoplastic polymer is present at a level of 40 to 90 wt %.
11. The polymeric composition of claim 10 , wherein the at least one thermoplastic polymer is present at a level of 50 to 85 wt %.
12. The polymeric composition of claim 3 , wherein the coated graphite flakes are present at a level of 4 to 25 wt %.
13. The polymeric composition of claim 4 , wherein the silica coating particles have an average diameter of 90 to 300 nm.
14. The polymeric composition of claim 5 , wherein the coated graphite flakes have a weight ratio of C:Si ranging from 9:1 to 4.5:1.
15. A polymeric composition comprising: a) at least one thermoplastic polymer; and b) 2 to 30 wt % graphite flakes that are coated with silica coating particles, with the total weight of the composition totaling to 100 wt %, wherein, the coated graphite flakes have a weight ratio of C:Si ranging from 10:1 to 4:1, and the silica particles have an average diameter of 102 to 400 nm.