Steady Shear and normal Stresses of Immiscible Polymer Blends

Abstract

Recently we proposed a new set of constitutive equation that can describe the interfacial contributions on the rheological properties of immiscible polymer blends with complex interfaces and successfully compared with dynamic experiments[1]. As Takahashi et. al. [2] have noticed, the domain structures remain unchanged under oscillatory flows with appropriate frequency and strain. So, it is relatively easy to consider such cases. Here we would like to explore it further to obtain the compact expressions for the steady shear properties. Furthermore we would like to compare them with experimental observations for the understanding of the morphological differences in the interfaces. In case of the shear flow, the domains can be deformed, ruptured, and aggregated due to the competition of flow and interfacial tension. That is why we proposed a phenomenological scheme to take into account such effects previously[1l. Three different characteristics of the interfaces have been successfully demonstrated as a conjunction with theoretical parameters and excess properties due to the interfaces.