Ultrasonic Absorption of Poly(vinyl propionate) and Poly(vinyl butyrate) in Toluene

Abstract

The Ultrasonic absorption in solutions of poly(vinyl propionate) and poly(vinyl butyrate) in toluene were measured by the pulse method in the frequency range 1-60 MHz and in the temperature range 0-60° C. The ultrasonic absorption of PVPr was represented by the single relaxation equation, while that of PVBu by the double relaxation equation. The relaxation of PVBu of lower frequency was ascribed to the rotation of side chains around the main chain, and that of higher frequency to the local rotation of side chain itself. The experimental results were discussed on the basis of the 2-state model.