Flow-induced crystallization of PB-1: From the low shear rate region up to processing rates

In this work a global view of flow-induced orientation in isotactic PB-1 is presented. The shear cell used in this work submits the sample to a homogeneous flow field and can be operated from the low shear rate region up into the highly oriented regime close to industrial processing conditions. For varying levels of shear rate and shear strain and for several crystallization temperatures, the transmitted intensity and birefringence are measured throughout the complete crystallization process and characteristic crystallization times are defined. Different regimes of flow-induced crystallization are observed as a function of an increased level of molecular orientation and stretch. Results concerning the Fase II to Fase I transformation in PB-1 are also presented.