Polyolefins (PO’s) are the largest and the most common group of plastics used in a wide variety of applications including the direct contact with food. To improve their processing and end-use properties, some additives, such as UV absorbers, antioxidants, etc…are added to the polymer. These additives are likely to migrate out of the materials towards the packaged product or towards the environment. For food, this migration during the product shelf life is a well-known phenomenon and the resulting risks have been taken into account in the regulation (EC 10/2011). Recent studies deal with the prediction of the migration thanks to transport modelling in order to design safe food packaging materials as this phenomenon is considered unavoidable. Meanwhile, for semi-crystalline polymeric systems, authors met difficulties with the mass balance made to characterize the systems after migration often showed a small fraction of additives unavailable for solvent extraction. In addition, a few studies have reported additives as being partially entrapped thanks to a confinement in peculiar domains in the interlamellar amorphous regions of the polymer. In this context, the objective of our study is to investigate the relationships between entrapped additives and polyolefin morphologies induced by their processing in order to assess if the confinement of the additives can limit their migration (overall rate and kinetics). For this purpose, we chose various systems including usual and model PO’s, with adjustable crystallization parameters, and fluorescent additives. A fluorescent molecular rotor (9-(dicyanovinyl)julolidine (DCVJ)) was also selected as a model additive in order to probe by its properties the very local environment of this additive when embedded in the matrices. Thermal treatments using fast cooling differential scanning calorimetry (FC-DSC) apparatus were applied to mimic plastic processing, and more particularly blown film extrusion