Theoretical Basis for Elasticity Measurements of Polymer Melts and Rubbers.

摘要

A review is presented of techniques that are used for the measurement of the viscoelasticity of fluids, concentrating on those most suited for polymer melts and rubbers. The review focuses on the assumptions made in the analyses and on the advantages and disadvantages of the techniques, rather than on a detailed examination of the theory needed to interpret the data obtained from them. The report primarily covers the techniques of oscillatory rheometry, stress relaxation, creep recovery and extrudate swell for the measurement of linear viscoelasticity properties. For the measurement of normal stress differences the steady shear rotation, exit pressure and hole pressure techniques are examined. The report is intended to guide those with limited understanding of rheology through the complexities of the measurement of viscoelasticity, and to direct those who wish to seek further information. It is the first of two reports on the measurement of viscoelasticity. The second report (1) focuses on the experimental application of the techniques to the characterization of the viscoelasticity of polymer melts and rubbers. (Copyright (c) Crown copyright 1994.)