Les Propriétés Dielectriques des Polymères Solides

Dielectric constants and loss factors of polyvinylformal have been measured for frequencies ranging from 400 c/sec. to 4 Mc/sec. The measurements covered a fairly wide temperature interval, both above and below the glass transition temperature, from −10 °C to 150°C. An important α absorption band was observed but no β band was found. This is attributed to the bridged structure of the polymer which prevents any independant movement of the polar side groups, in accordance with the hypothesis of Deutsch, Hoff and Reddish concerning the molecular mechanism of the β absorption bands. Copyright © 1961 Wiley‐VCH Verlag GmbH & Co. KGaA, WeinheimSCOPUS: ar.j