Polymer composition for use in an antenna system
A polymer composition comprising a dielectric material distributed within a polymer matrix is provided. The dielectric material has a volume resistivity of from about 0.1 ohm-cm to about 1×10 12 ohm-cm, wherein the polymer matrix contains at least one thermotropic liquid crystalline polymer, and further 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.
1. An antenna system that comprises a substrate that includes a polymer composition and at least one antenna element configured to transmit and receive radio frequency signals, wherein the antenna element is coupled to the substrate, wherein the polymer composition comprises a dielectric material distributed within a polymer matrix, wherein the dielectric material has a volume resistivity of from about 0.1 ohm-cm to about 1×10 12 ohm-cm, wherein the polymer matrix contains at least one thermotropic liquid crystalline polymer, and further 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.
2. The antenna system polymer composition of claim 1 , 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.
3. The antenna system polymer composition of claim 1 , 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.
4. The antenna system polymer composition of claim 1 , 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 1.0 or less.
5. The antenna system polymer composition of claim 1 , wherein the dielectric material contains an inorganic oxide material.
6. The antenna system polymer composition of claim 5 , wherein the inorganic oxide material includes titanium dioxide particles.
7. The antenna system polymer composition of claim 5 , wherein the inorganic oxide material includes inorganic oxide whiskers.
8. The antenna system polymer composition of claim 7 , wherein the whiskers are zinc oxide whiskers.
9. The antenna system polymer composition of claim 7 , wherein the whiskers have a central body and a plurality of needle crystals extending radially therefrom.
10. The antenna system polymer composition of claim 1 , wherein the dielectric material includes an inorganic oxide material having a volume resistivity of from 0.1 ohm-cm to about 500 ohm-cm.
11. The antenna system polymer composition of claim 1 , wherein the dielectric material includes a carbon material having a volume resistivity of from about 1×10 3 to about 1×10 12 ohm-cm.
12. The antenna system polymer composition of claim 1 , wherein the dielectric material includes an electrically conductive material having a volume resistivity of less than about 0.1 ohm-cm and an insulative material having a volume resistivity of greater than about 1×10 12 ohm-cm.
13. The antenna system polymer composition of claim 12 , wherein the electrically conductive material includes a carbon material and the insulative material includes an inorganic oxide material.
14. The antenna system polymer composition of claim 13 , wherein ratio of the weight percentage of the inorganic oxide material to the weight percentage of the carbon material is from about 3 to about 100.
15. The antenna system polymer composition of claim 1 , wherein the thermotropic crystalline polymer is an aromatic polyester that contains repeating units derived from 4-hydroxybenzoic acid.
16. The antenna system polymer composition of claim 1 , wherein the thermotropic liquid crystalline polymer has a total amount of repeating units derived from naphthenic hydroxycarboxylic and/or naphthenic dicarboxylic acids of about 10 mol. % or more.
17. The antenna system polymer composition of claim 16 ,
wherein the thermotropic liquid crystalline polymer has a total amount of repeating units derived from naphthalene-2,6-dicarboxylic acid of about 10 mol. % or more.
18. The antenna system polymer composition of claim 1 , wherein the polymer composition further comprises a laser activatable additive.
19. The antenna system polymer composition of claim 18 , wherein the laser activatable additive contains spinel crystals having the following general formula:
AB 2 O 4
wherein,
A is a metal cation having a valance of 2; and
B is a metal cation having a valance of 3.
20. The polymer composition of claim 19 , wherein the spinel crystals include MgAl 2 O 4 , ZnAl 2 O 4 , FeAl 2 O 4 , CuFe 2 O 4 , CuCr 7 O 4 , MnFe 2 O 4 , NiFe 7 O 4 , TiFe 2 O 4 , FeCr 2 O 4 , MgCr 2 O 4 , or a combination thereof.
21. The antenna system polymer composition of claim 1 , wherein the polymer composition further comprises a fibrous filler.
22. The antenna system polymer composition of claim 21 , wherein the fibrous filler includes glass fibers.
23. The antenna system polymer composition of claim 1 , wherein the composition has a melt viscosity of from about 5 to about 100 Pa-s, as determined at a shear rate of 1,000 seconds −1 and a temperature of 350° C.
24. The antenna system polymer composition of claim 1 , wherein the composition comprises from about 15 wt. % to about 85 wt. % of thermotropic liquid crystalline polymers and from about 10 wt. % to about 70 wt. % of the dielectric material.
25. The antenna system of claim 1 , wherein the radio frequency signals are 5G signals.
26. The antenna system of claim 1 , wherein the at least one antenna element has a feature size that is less than about 1,500 micrometers.
27. The antenna system of claim 1 , wherein the at least one antenna element comprises a plurality of antenna elements.
28. The antenna system of claim 27 , wherein the plurality of antenna elements are spaced apart by a spacing distance that is less than about 1,500 micrometers.
29. The antenna system of claim 27 , wherein the plurality of antenna elements comprise at least 16 antenna elements.
30. The antenna system of claim 27 , wherein the plurality of antenna elements are arranged in an array.
31. The antenna system of claim 30 , wherein the array is configured for at least 8 transmission channels and at least 8 reception channels.
32. The antenna system of claim 30 , wherein the array has an average antenna element concentration of greater than 1,000 antenna elements per square centimeter.
33. The antenna system of claim 1 , further comprising a base station, and wherein the base station comprises the at least one antenna element.
34. The antenna system of claim 1 , further comprising at least one of a user computing device or a repeater, and wherein the at least one of the user computing device or the repeater base station comprises the at least one antenna element.
35. The antenna system of claim 12 , wherein the insulative material constitutes from about 30 wt. % to about 60 wt. % of the polymer composition.
36. The antenna system of claim 14 , wherein the polymer composition exhibits a dielectric constant of 8.36 or more.