%0 Journal Article %T How nucleating particles migration affects the fractionated crystallization of isotactic polypropylene/polystyrene immiscible blends %+ Centre de Mise en Forme des Matériaux (CEMEF) %+ Institut Clément Ader (ICA) %+ Università degli studi di Genova = University of Genoa (UniGe) %+ University of the Basque Country/Euskal Herriko Unibertsitatea (UPV/EHU) %+ Ikerbasque - Basque Foundation for Science %A Fenni, Seif Eddine %A Spigno, Mariangela %A Wang, Wei %A Costanzo, Andrea %A Müller, Alejandro %A Cavallo, Dario %< avec comité de lecture %Z KTK-4528 %Z DOCA-11 %Z MSC %@ 0040-6031 %J Thermochimica Acta %I Elsevier %V 719 %P 179407 %8 2023 %D 2023 %R 10.1016/j.tca.2022.179407 %K Fractionated crystallization %K Immiscible blends %K Nucleating agents %K Polypropylene Migration %Z Engineering Sciences [physics]Journal articles %X We investigate the inter-phase migration of nucleating particles and their effect on the fractionated crystalli-zation of polypropylene droplets dispersed in an immiscible polystyrene matrix by preparing melt-mixed 90/10wt% PS/PP blends with selected nucleating agents. Different concentrations of nucleating agents (NAs): Phta-locianene Blue, NA11, Talc, and sodium benzoate, were initially incorporated either in neat PP or in neat PS.Then the different PS/PP/NAs blends were prepared. Contact angles were determined for the neat polymers andthe NAs, and the results indicated that, from a thermodynamics point of view, all NAs should remain or migrateto the PS phase. According to SEM observations, a sea-island morphology was obtained that did not vary with NAaddition. Hence the results should be independent of differences in the morphology.PP droplets crystallized in neat blends in three well-differentiated crystallization peaks (i.e., fractionatedcrystallization). The NAs induce a concentration-dependent increase in the high-temperature crystallization peakat the expense of reducing the low-temperature peaks, as droplets become in contact with or contain the NAs.When compared at a constant concentration in one of the phases, the nucleating agents have efficiencies thatdecrease in the order: Pht Blue ≈NA11>Talc>Sod Benz. Surprisingly, for the three most effective NAs, it wasfound that adding them initially to the PS phase led to a much higher nucleation efficiency (evaluated in terms ofincreases in peak crystallization temperature) than adding them to PP. This indicates that these NAs, initiallypresent in the PS phase, migrate to the interface or to the bulk of the PP phase (against thermodynamics). SodBenz was the only exception, as it shows a higher thermodynamic affinity to the PS phase. We explain themigration of most particles from the PS phase to the phases’ boundary or to the bulk of the PP droplets byconsidering that kinetic factors dominate the behavior, as, from a rheological perspective, the minor component(PP) always displays a lower viscosity than the matrix component (PS) under the chosen mixing conditions. %G English %2 https://hal-mines-albi.archives-ouvertes.fr/hal-03879565/document %2 https://hal-mines-albi.archives-ouvertes.fr/hal-03879565/file/How-nucleating-particles-migration-affects-the-fractionated-crystallization-of-isotactic-polypropylene-polystyrene-immiscible-blends.pdf %L hal-03879565 %U https://hal-mines-albi.archives-ouvertes.fr/hal-03879565 %~ INSTITUT-TELECOM %~ ENSMP %~ UNIV-TLSE3 %~ MINES-ALBI %~ CNRS %~ INSA-TOULOUSE %~ ENSMP_CEMEF %~ EMAC %~ PARISTECH %~ ICA-ALBI %~ PSL %~ ENSMP_DEP_MM %~ ICA %~ INSA-GROUPE %~ ENSMP_DR %~ INSTITUTS-TELECOM %~ ENSMP-PSL %~ UNIV-UT3 %~ UT3-INP %~ UT3-TOULOUSEINP