High-Field Conduction in Films of Mylar and Teflon

Abstract

Conduction currents in Mylar and Teflon films were measured at applied field strengths of 2–1400 kV·cm−1 and at a number of temperatures in the range 70°–163°C. The samples were carefully conditioned. The current varied with voltage as exp (αV 0 1/2), and its temperature behavior was consistent with an activation process, giving an activation energy for conduction essentially independent of sample thickness, except at low fields. This change in activation energy with thickness at low fields, along with breaks in the Schottky plots are attributed to space‐charge effects. The data did not fit a hyperbolic sine relationship previously applied to this system in support of an ionic mechanism. The results are discussed in terms of available theories of conduction in solids.