Silicone oils (polymerized siloxanes with organic side chains) are silicon analogues of carbon-based organic compounds and can form (relatively) long and complex molecules based on silicon rather than carbon.

Silicone oils are excellent electrical insulators and have a good heat-transfer and thermal stability. Furthermore, they are non-flammable, unlike their carbon analogues. The main applications are as lubricants or hydraulic fluids.

The application illustrates a thermal conductivity determination in the temperature range from room temperature to 100 °C of a silicon oil. The thermal diffusivity was measured with an LFA where a special sample holder made for liquids, pastes and powders was used.

Furthermore, a DSC PT 10 was used for the measurement of the specific heat capacity (Cp). The thermal conductivity was then calculated with the density, thermal diffusivity and the Cp values.

The specific heat capacity is increasing with temperature, whereas the thermal diffusivity and thermal conductivity are decreasing with increasing temperature.

Suitable measuring device