Dependence of Resistivity in Low-Density Polyethylene on Space Environment Parameters

The conductivity of high-resistivity polymer films is dependent on the magnitude of applied electric field, repeated electric field exposure, and sample temperature. A traditional constant voltage method was used, maintained under vacuum to more closely resemble the space environment. Both the strength of the applied voltage and the thickness of low-density polyethylene (LDPE) samples were varied to determine the electric field dependence of internal polarization and the leakage current most appropriate in calculating the resistivity. Repetition of same field strength measurements determined the influence of sample history and charging memory. Measuring the resistivity from cryogenic temperatures to well above the glass transition temperature of LDPE allowed for separation of hopping conductivity regimes and correlation with internal morphology. In combination, these measurements provide a picture of the resistivity behavior of LDPE.