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Vladimir N. Matveenko, Eugine A. Kirsanov
Structural description of polymer systems in the field of
linear viscoelasticity
Abstract
Abstract. A structural rheological model is
presented, including kinetic equations of the processes of formation and
destruction of aggregates of particles or associates of macromolecules. The
shape of rheological curves is determined by the state of the structure of
matter and the change in structure as a result of oscillating shear flow. An
integral characteristic of the structure is the number of meshes or contacting
particles-macromolecules per unit volume. Rheological equations contain three
(or two) coefficients (parameters) that have a clear physical meaning, their
value is determined by the physico-chemical and structural state of the system
during the flow. The viscous and elastic properties of polymers are considered
independently of each other. The rheological equations of the model are used to
interpret the frequency dependences of the dynamic modules of some melts and
polymer solutions. The existing relationship between the coefficients of
rheological equations that describe viscosity and elasticity is explained by
their common structural nature.
Key words: viscoelasticity,
oscillating shear flow, loss modulus, storage modulus, dynamic viscosity,
dynamic elasticity, melts and polymer solutions, structural rheological model,
kinetic equations of structure formation and destruction
Copyright (C) Chemistry Dept., Moscow State University, 2002
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