Generalized rheological characteristic of plastic disperse systems with polymeric and low-molecular dispersion media (matrices)

Abstract

Analysis of literature data on the flow of polymeric and oligomeric compositions as well as on systems of low viscous dispersion media containing a high-disperse filler (carbon black, silica, high-disperse chalk) has been carried out. As the basic idea, a proposal is made that their viscosity anomaly is due not to the matrix viscosity anomaly, but to the gradual breakdown of the filler structural skeleton with increasing shear stressτ and shear rate$\dot \gamma$. The viscosity anomaly of those compositions is determined by the zeroshear but not by the apparent matrix viscosity. A general relationship has been found to describe the flow of such systems depending on the zero-shear matrix viscosity values,η ₀, their yield stress,τ _y , and filler volume concentration$\varphi :\tau = \tau _y + K\varphi \eta _o^n \dot \gamma ^n$, whereK=4.9 andn=0.69 are constants.