Measurement of the Dielectric Properties and Thermal Expansion of Polymers from Ambient to Liquid Helium Temperatures

Abstract

A three terminal combined dilatometric and dielectric cell for measuring the thermal expansion and dielectric properties of high polymers or other solids down to liquid helium temperatures is described. Some preliminary results on fused silica and poly (dl propylene oxide) are presented. The frequency range of 50 Hz to 10 kHz and the resolutions, at 1 kHz, of 1×10−6 pF in capacitance and 1×10−6 in dissipation factor are determined by the characteristics of the capacitance bridge used.