Ion mobilities in non-polar dielectric liquids: silicone oils

Silicone oils have been applied as replacements for mineral oils in transformers and other electrical equipment. Investigations of their electrical and thermo-physical properties have been carried out. Few studies of the measurements of positive and negative ions in these liquids exist. The present paper summarizes the data published. The modes of charge transport in these liquids are discussed on the basis of the Stokes model, which leads to the Walden´s rule. Comparison with data of other dielectric liquids leads to the conclusion that Walden´s rule is not applicable for a variety of dielectric liquids.