Molecular consideration in selection of composite insulating materials and insulation systems

To many engineers not directly concerned with the more basic theories of dielectrics behavior, and, it must be recognized, even to some persons having a good knowledge of the electrical properties of individual insulating materials, it is often difficult to understand the detailed behavior of any particular insulation system. In other papers of this tutorial session, eminent speakers, well versed in their fields, have outlined the various fundamental relationships governing the properties of materials as related to structure of the individual materials, and it is the purpose of this paper to discuss briefly some of the phenomena which arise when combinations of insulating materials are used in more practical situations, and to focus discussion on how these phenomena can be related to basic relationships already established. With this more detailed understanding, it is also possible to see what advances can be made, and in what direction, for future development work in improved composite dielectric materials and insulation systems generally.