Accession Number : ADA019180

Title :   Studies of Molecular Relaxation in Polypropyleneoxide Solutions by Dielectric Relaxation and Brillouin Scattering.

Descriptive Note : Technical rept.,


Personal Author(s) : Yano,S. ; Rahalkar,R. R. ; Hunter,S. P. ; Wang,C. H. ; Boyd,R. H.

Report Date : 02 JUN 1975

Pagination or Media Count : 32

Abstract : Dielectric relaxation and Brillouin scattering are jointly used in studying molecular relaxation in polypropyleneoxide (PPO) and its solutions in methylcyclohexane. The dielectric method was applied to the more concentrated (100, 80, 60 volume percent) solutions over a wide temperature and frequency range (30 Hz to 8 GHz) in order that the variation in activation energy characteristic of glass-forming substance could be delineated. The present work extends previous work on the undiluted polymer to higher frequencies so that a total range of 12 decades in log f(max) as a function of temperture is now available. A maximum in the hypersonic attenuation versus temperature curve was observed in each polymer solution. The Brillouin scattering follows different activation parameters and occurs somewhat more rapidly than the dielectric relaxation.

Descriptors :   *Polymers, Relaxation, Temperature, Dielectric properties, Solutions(Mixtures), Concentration(Chemistry), Glycols, Light scattering, Molecular rotation, Activation energy, Mechanical properties

Subject Categories : Polymer Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE