On the rheology and microstructure of immiscible polymer blends in eccentric Taylor–Couette flow

Various consumer products contain droplets that are dispersed in a matrix. The rheological behavior and microstructural characteristics of these products are important determinants of product quality. This paper computationally investigates the rheological behavior and microstructural dynamics of multiple droplets dispersed in a polymeric matrix fluid in a steady eccentric Taylor–Couette flow field. A large eccentricity ratio was chosen for the cylinder system in order to allow flow recirculation to occur. A thermodynamically consistent model was used to describe the dynamics of the blend, including breakup and coalescence. The qualitative behavior of the droplets was found to be governed by the relative rotation and eccentricity of the cylinders. In addition, the matrix viscoelasticity was observed to have a large quantitative impact on the droplet characteristics. The findings of this research encourage us to experimentally assess the predictive capability of the model in the eccentric Taylor–Couette system.

► First simulation of the dynamics of multiple droplets dispersed in a viscoelastic matrix in an eccentric annular flow field. ► The cylinder eccentricity and the different types of simple shear have a large qualitative impact on the droplet dynamics. ► Results suggest that modifying the rheology of the matrix is a feasible strategy for tailoring the droplet characteristics.