Flow distribution in shear-induced crystallisation of melt polymer: A prediction from morphological distribution of solid polymer

The present study presents a method to predict the flow distribution imposed on an injection moulded melt crystallised isotactic polypropylene (iPP) from its experimentally determined morphological distribution. A microrheological model, based on the Doi–Edwards model, was used to calculate the flow-induced free energy for the flow-induced crystallisation. The low limit flow field required to generate the final structures was then obtained. The effect of Cu-phthalocyanine (CuPc), a nucleating agent, on the flow history was also studied. Instead of geometric positions, structural parameters such as molecular orientation and crystallinity were correlated to the flow history of the injection-moulded iPP. The work provides a simple approach to predict flow–structure relationships for complex thermo-mechanical processing treatments, which can then guide the realistic design and control of the flow-induced crystallisation of polymers.