Electrical Properties of Elastomers

Significance and Test Method

Standard elastomers are usually not or only slightly conductive or dissipative. They therefore often tend to become electrostatically charged. Whether and to what extent elastomer components become charged in use, whether they are conductive or insulating, depends on the structure of the elastomer compound.

Standard carbon blacks, which are used as fillers in most elastomer compounds, generally do not offer any electrical conductivity. To achieve this, manufacturers sometimes use conductive carbon blacks, aluminium or stainless steel fibres, carbon nanotubes or high-priced silver fillers. However, these fillers not only influence the electrical properties of the material, but also its mechanical characteristics.

Significance for Application Technology

Resistance and potential difference measurements provide information about the electrical properties of elastomers. They help to assess the behaviour of components in use and the risks of electrostatic charging or electrochemical degradation. They provide information on the basis of which decisions can be made about the need for additional measures, suitable discharge methods or electrical protection measures.

The Tests

Tests for electrical insulation materials, resistivity and other electrical characteristics are described in various national, international standards, technical standards and factory regulations.

At the Elastomer Institut Richter we measure the electrical properties of elastomers in accordance with DIN ISO IEC 60093, DIN 50918, ASTM D 4496, ASTM D257, DBL 5527 or SAE J 1645.

We carry out the following measurements:

  • Measurement of volume resistivity and volume resistivity (volume resistance) on sheet material. Minimum size of the test plates 80×80×2 mm
  • Measurement of surface resistance and specific surface resistance on sheet material
  • Measurement of resistance on test panels and finished parts, also in combination with immersion tests
  • Measurement of the resistance of test plates and finished parts, also under deformation or stress
  • Measurement of potential difference in accordance with DBL 5527, analogous to DIN 50918
  • Measurement of conductivity or insulation effect in accordance with DBL 5527