Elastomer composites with high dielectric constant
Elastomer compositions with high dielectric constants are disclosed. Embodiments of the disclosure include a high dielectric constant (high-K) elastomeric composition comprising an elastomer, carbon black (CB), and organoclay (OC). The composition is not dependent on any raw material with inherent high-k or any metal oxide type material that changes conductivity with applied voltages. The composition instead uses distributed electric fields and polarizability with carbon black and organoclays. This allows for a high-k material through polarizability with limited large-scale electron sharing.
1. A non-conducting polymer composition comprising:
a polymer,
an organically modified clay, and
carbon black particles, wherein the carbon black particles are low structure carbon black particles,
wherein particles of the organically modified clay are larger than the carbon black particles, and
wherein the non-conducting polymer composition has a dielectric constant greater than 5 and less than 1000 and a dielectric loss (tan delta) of less than 10%.
2. The polymer composition of claim 1 , wherein the organically modified clay has a platy shape.
3. The polymer composition of claim 1 , wherein the organically modified clay insulative filler is a high aspect ratio dielectric filler.
4. The polymer composition of claim 1 , wherein the organically modified clay and the carbon black particles form a structured composite in which the organically modified clay separates particles of the carbon black particles.
5. The polymer composition of claim 1 , wherein the polymer is an elastomer.
6. The polymer composition of claim 1 , wherein the polymer comprises 30-55% by weight of the polymer composition.
7. The polymer composition of claim 1 , wherein the carbon black particles comprise 5-40% by weight of the polymer composition.
8. The polymer composition of claim 1 , wherein the organically modified clay comprises 1-7% by weight of the composition.
9. The polymer composition of claim 1 , wherein the organically modified clay is an ammonia treated montmorillonite.
10. The polymer composition of claim 1 , wherein the carbon black particles have a particle size range from 10-900 nanometers.
11. The polymer composition of claim 1 , further comprising an inorganic filler.
12. The polymer composition of claim 11 , wherein the inorganic filler comprises 10-25% by weight of the composition.
13. The polymer composition of claim 11 , wherein the inorganic filler is one or more of (Nb,ln)TiO 2 , rutile-TiO 2 , SiO 2 , ZnO, tin oxide, lead oxide, iron oxide, and calcium oxide.
14. An electrical stress grading apparatus comprising a non-conducting polymer composition comprising:
a polymer,
an organically modified clay, and
carbon black particles, wherein the carbon black particles are low structure carbon black particles,
wherein the organically modified clay and the carbon black particles form a structured composite in which the organically modified clay separates particles of the carbon black particles such that the composition is non-conducting, and
wherein the non-conducting polymer composition has a dielectric constant greater than 5 and less than 1000 and a dielectric loss of (tan delta) less than 10%.
15. The electrical stress grading apparatus of claim 14 , wherein the dielectric constant of the apparatus is 5-50.