Electrical conductivity of polypropylene

✍ Scribed by Richard A. Foss; Walter Dannhauser

• Publisher: John Wiley and Sons
• Year: 1963
• Tongue: English
• Weight: 397 KB
• Volume: 7
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.1963.070070318

✦ Synopsis

Abstract

The steady‐state (d.c.) electrical conductivity of polypropylene has been measured as a function of temperature (25–150°C.) and field strength (0–94 kv./cm.). The temperature coefficient of the conductivity is 34.6 kcal./mole expressed as an activation energy. This is much larger than the activation energy for diffusion of small molecules in the same polymer. Thus, ionization rather than diffusion appears to be the primary activation process. The conductivity is nonohmic; the conductance quotient is a linear function of field strength but is larger than predicted by Onsager's theory. The ion “jump distance” as evaluated from the isothermal field dependence, is the same order of magnitude as the diffusional mean free path estimated from diffusion studies in other polymers. The conductivity, conduction activation energy, and field dependence appear to be relatively insensitive to polymer crystallinity.