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Dynamics of spinodal decomposition in polymer blends
Abstract
A numerical study investigating the dynamics of spinodal decomposition in polymer blends in three dimensions has been performed. The objective of this research was to investigate the effects of the chain-like nature of polymer molecules on the formation and growth of the phase separating domains and to interpret the results of this numerical study to get a better understanding of the experimental observations that are unique to polymeric systems. The relative contributions of the enthalpic and entropic parts of the interfacial free energy of the inhomogeneous mixture have been computed for the non-hydrodynamic regime of spinodal decomposition in the quiescent polymer blend. It has been shown that the dominance of the entropic contribution leads to the freezing of the dispersed domain morphology and a coarsening mechanism based on the transport of long chain molecules parallel to the interface can explain this novel feature characteristic of polymer blends. Calculations have been also made to study spinodal decomposition under simple shear flow by making a mean field approximation for the velocity field. The domain growth has been found to be highly anisotropic with enhanced growth along the flow direction than in the directions perpendicular to the flow. The potential of the computational scheme used in the present calculations, for applications in other systems, is also discussed.
Subject Area
Materials science|Chemical engineering|Plastics
Recommended Citation
Kotnis, Mahesh Arvind, "Dynamics of spinodal decomposition in polymer blends" (1993). Doctoral Dissertations Available from Proquest. AAI9316684.
https://scholarworks.umass.edu/dissertations/AAI9316684