List of Characteristics/Properties of Ebonite
<Insulation properties>
Very high insulation properties.
All hydrocarbon polymers have insulation properties.
Especially, ebonite provides excellent insulation performance.
<High-frequency dielectric loss>
Extremely low.
Perfect for wired lines as much as wireless.
<Aging resistance>
Provides extremely high resistance especially against ultraviolet rays.
<Free sulfur>
Extremely low free sulfur. Contacting parts with metal also provide low sulfurization.
<Acid resistance, alkaline resistance>
Provides excellent resistance against chemicals, including acid and alkali, at room temperature.
<Mechanical strength>
Has hardness and strength comparable to metal.
<Appearance and workability>
Gives dark shiny gloss when polished. Easy to conduct a precision work and forming.
<Water absorbability>
Water absorbability is extremely low compared to soft rubber.
Very high moisture resistance.
Therefore, there is no rapid reduction in insulation properties when moisture is absorbed.
The list below shows the characteristic of ebonite.
Please use as reference values.
| No. | Type | Unit | Rod | Plate |
|---|---|---|---|---|
| 1. | Specific gravity | % | 1.16 | 1.14 |
| 2. | Amount of water absorption | mg/100cm² | 0.25‑0.3 | 0.2‑0.25 |
| 3. | Heating resistance (appearance) | - | No change | No change |
| - | (dimension change) | % | No change | No change |
| 4. | Thermal resistance | mm | 2‑3 | 2‑3 |
| 5. | Tensile strength | kg/mm² | 6‑7 | 6‑7 |
| 6. | Elongation | % | 4‑6 | 4‑6 |
| 7. | Compressive strength | kg/mm² | 8‑10 | 8‑10 |
| 8. | Bending strength | kg/mm² | 10‑11 | 10‑11 |
| 9. | Ash content | % | 1‑3 | 1‑3 |
| 10. | Acetone extraction | % | 4.3‑4.7 | 4.3‑4.7 |
| 11. | Dielectric breakdown strength | kV/mm | 27‑29 | 27‑29 |
| 12. | Specific resistance(volume) | Ωcm | 10 to the 13th power or more | 10 to the 15th power or more |
| - | Specific resistance(surface) | Ω | 10 to the 13th power or more | 10 to the 15th power or more |
| 13. | Dielectric power factor | (10Mc)x10 to the negative 4th power | 70‑90 | 70‑90 |
| 14. | Permittivity | 10Mc | 3‑3.2 | 3‑3.2 |
| 15. | Free sulfur | % | 0.3‑0.9 | 0.3‑0.9 |
| 16. | Softening point | ℃ | 80 | 80 |