The morphology of immiscible polymer blends develops during melt processing in a very complex way. An increase in elasticity of the cross-linked droplets should reduce their deformability under shear. From the droplet deformation experiments that have been carried out at various extents of cross-linking, the importance of the elasticity ratio for the viscosity ratio cannot be demonstrated since the increase in the viscosity ratio due to the cross-linking also results in a decrease of the deformability of the dispersed phase. The influence of flow during the crystallization process is nowadays widely investigated. Thus, the ability of the shear to accelerate crystallization has been linked to the presence of long chain molecules in the polymer. During dynamic experiments, other parameters have to be taken into account, for instance, the heterogenous nature of the crystallization along the fiber under shear flow.