TRANSPORT PROCESSES IN A VISCOELASTIC BINARY MIXTURE

Abstract

Generalized thermohydrodynamics is used to provide for a basis to compute transport coefficients of a binary isothermal solution consisting of a viscoelastic fluid in a viscous solvent. A description is made of the states of this system using, besides the conventional conserved densities, a set of non-conserved variables provided by the stress tensor and the mass flux of one of the components. Within a linearized scheme, the solution to the evolution equations obeyed by the latter ones provides a set of constitutive equations which are in general both wave vector and frequency dependent. When the constitutive equations are substituted into the conservation equations, a complete set is obtained from which all relevant quantities may be computed. These involve wave vector and frequency dependent expressions for the transport coefficients as well as the dynamic structure factor which may be obtained by light or neutron scattering. These results are analyzed and compared with other ones existing in the literature.