Polymer composition for an electronic device
A polymer composition is provided. The polymer composition comprises a liquid crystalline, an electrically conductive filler, and a mineral filler. The polymer composition exhibits a surface resistivity of from about 1×10 12 ohms to about 1×10 18 ohms as determined in accordance with ASTM D257-14.
1. A polymer composition for use in an electronic device, wherein the polymer composition comprises a polymer matrix comprising a liquid crystalline polymer and a mineral filler, and further wherein the polymer composition exhibits a surface resistivity of from 4.2×10 15 ohms to about 1×10 18 ohms as determined in accordance with ASTM D257-14.
2. The polymer composition of claim 1 , wherein the polymer composition exhibits a volume resistivity of 1×10 10 ohm-m to about 1×10 16 ohm-m as determined in accordance with ASTM D257-14.
3. The polymer composition of claim 1 , wherein the polymer matrix constitutes from about 30 wt. % to about 80 wt. % of the polymer composition.
4. The polymer composition of claim 1 , wherein the liquid crystalline polymer contains one or more repeating units derived from an aromatic hydroxycarboxylic acid, wherein the hydroxycarboxylic acid repeating units constitute about 40 mol. % or more of the polymer.
5. The polymer composition of claim 4 , wherein the liquid crystalline polymer contains repeating units derived from 4-hydroxybenzoic acid, 6-hydroxy-2-naphthoic acid, or a combination thereof.
6. The polymer composition of claim 4 , wherein the liquid crystalline polymer contains repeating units derived from 4-hydroxybenzoic acid in an amount of from about 30 mol. % to about 90 mol. % of the polymer and contains repeating units derived from 6-hydroxy-2-naphthoic acid in amount of from about 1 mol. % to about 30 mol. % of the polymer.
7. The polymer composition of claim 4 , wherein the liquid crystalline polymer further contains repeating units derived from terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, hydroquinone, 4,4′-biphenol, acetaminophen, 4-aminophenol, or a combination thereof.
8. The polymer composition of claim 1 , wherein the polymer composition comprises an electrically conductive filler including a carbon material.
9. The polymer composition of claim 8 , wherein the carbon material has a volume resistivity of less than about 1 ohm-cm.
10. The polymer composition of claim 8 , wherein the carbon material includes graphite, carbon black, carbon fibers, graphene, carbon nanotubes, or a combination thereof.
11. The polymer composition of claim 1 , wherein the polymer composition comprises an electrically conductive filler in an amount of from about 0.5 to about 20 parts by weight per 100 parts by weight of the polymer matrix.
12. The polymer composition of claim 1 , wherein the mineral filler is present in the polymer composition in an amount of from about 10 to about 80 parts by weight per 100 parts by weight of the polymer matrix.
13. The polymer composition of claim 12 , wherein a weight ratio of the mineral filler to the electrically conductive filler ranges from about 2 to about 500.
14. The polymer composition of claim 12 , wherein the mineral filler contains mineral particles, mineral fibers, or a combination thereof.
15. The polymer composition of claim 14 , wherein the mineral particles include talc, mica, or a combination thereof.
16. The polymer composition of claim 14 , wherein the mineral fibers include wollastonite.
17. The polymer composition of claim 14 , wherein the mineral fibers have a median diameter of from about 1 to about 35 micrometers.
18. The polymer composition of claim 14 , wherein the mineral fibers have an aspect ratio of from about 1 to about 50.
19. The polymer composition of claim 1 , wherein the polymer composition has a melt viscosity of from about 10 to about 250 Pa-s, as determined in accordance with ISO Test No. 11443:2014 at a shear rate of 1,000 s −1 and temperature that is 15° C. above a melting temperature of the composition.
20. The polymer composition of claim 1 , wherein the polymer composition exhibits a dielectric constant of about 4 or more and a dissipation factor of about 0.3 or less, as determined at a frequency of 2 GHz.
21. The polymer composition of claim 20 , wherein the composition exhibits a dielectric constant after being exposed to a temperature cycle of from about −30° C. to about 100° C., wherein the ratio of the dielectric constant after the temperature cycle to the dielectric constant prior to the heat cycle is about 0.8 or more.
22. The polymer composition of claim 20 , wherein the composition exhibits a dissipation factor after being exposed to a temperature cycle of from about −30° C. to about 100° C., wherein the ratio of the dissipation factor after the temperature cycle to the dissipation factor prior to the heat cycle is about 1.3 or less.
23. The polymer composition of claim 1 , wherein the polymer composition is free of spinel crystals.
24. A substrate comprising the polymer composition of claim 1 , wherein conductive circuit traces are disposed on a surface of the substrate.
25. An electronic device comprising the substrate of claim 24 , wherein the substrate is molded onto a singulated carrier portion.
26. The electronic device of claim 25 , wherein the singulated carrier portion comprises a metal.
27. The electronic device of claim 25 , wherein the substrate contains a channel within which a seed layer is disposed, and further wherein the circuit traces are disposed on the seed layer.
28. The electronic device of claim 27 , wherein the channel is formed by a laser.