Morphology and phase inversion of EPDM/PP blends - Effect of viscosity and elasticity

For the viscosity ratios used (10−3 to 102), a substantial composition range of co-continuity morphology was found. Our results suggest that the melt viscosity and elasticity of the major phase are the main parameters that govern the co-continuity region and phase inversion. Results obtained for phase inversion compositions were also compared with those predicted by several empirical models developed to predict the phase inversion point using dynamic viscoelastic properties of blend components. A good fit of our experimental results was obtained by adjusting the general relationship of the composition as a function of the viscosity ratio and by introducing an exponent and prefactor.