Accession Number : AD0663703

Title :   THE DAMPED TORSIONAL OSCILLATOR MODEL FOR POLYMER MOLECULES.

Descriptive Note : Technical rept.,

Corporate Author : PRINCETON UNIV N J FRICK CHEMICAL LAB

Personal Author(s) : Tobolsky,Arthur V. ; DuPre,Donald B.

Report Date : DEC 1967

Pagination or Media Count : 14

Abstract : An alternative model to the Rouse-Bueche (RB) theory of viscoelasticity is presented, in which the segments are torsional oscillators consisting of two or three backbone links, and the damping is due to hindered internal rotation (DTO model). The mathematical treatment of these two models is essentially identical, but the physical interpretation of the constants used is very different. The DTO model has previously been applied by one of us to the interpretation of viscoelastic data. It is applied to the interpretation of dielectric loss data. It is shown that dielectric measurements in dilute solution should very readily discriminate between the two approaches. Finally it is shown that the relaxation time computed from the DTO model is in very close agreement with published NMR data on poly(propylene) oxide 2025, whereas the RB relaxation time is 1000 times shorter than the experimental result. The postulates of the DTO model appear to be confirmed for this low molecular weight polymer. (Author)

Descriptors :   (*POLYMERS, *VISCOELASTICITY), THEORY, OSCILLATION, DAMPING, MATHEMATICAL MODELS, STEREOCHEMISTRY, DIELECTRIC PROPERTIES, SOLUTIONS(MIXTURES), EPOXY RESINS, NUCLEAR MAGNETIC RESONANCE, RELAXATION TIME

Subject Categories : Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE