Ingeniería QuímicaNo Descriptionhttps://ri.itba.edu.ar/handle/123456789/40392024-03-28T19:50:22Z2024-03-28T19:50:22Z21Fluid dynamics of the phase inversion process in the bulk polymerization of high impact polystyreneMaffi, Juan M.Estenoz, Dianahttps://ri.itba.edu.ar/handle/123456789/40402022-12-07T18:14:39Z2021-01-01T00:00:00Zdc.title: Fluid dynamics of the phase inversion process in the bulk polymerization of high impact polystyrene
dc.contributor.author: Maffi, Juan M.; Estenoz, Diana
dc.description.abstract: "In the synthesis of HIPS, phase inversion (PI) is the critical point at which a dispersed PS-rich phase becomes a continuous matrix, leaving behind a PB-rich phase as dispersed particles that may contain occluded PS-rich droplets inside (occlusions). The size and shape of these particles essentially determine the mechanical properties of the material, which makes PI a critical point during the reaction. In this work, the most popular mechanism for PI – an imbalance between coalescence and break-up of dispersed particles – is assessed through a population balance model, coupled with a heterogeneous polymerization model. Results are adjusted and discussed with experimental evidence gathered from TEM images."
2021-01-01T00:00:00ZPhase inversion prediction during the bulk synthesis of high-impact polystyrene: a fluid-dynamic approachMaffi, Juan M.Estenoz, Dianahttps://ri.itba.edu.ar/handle/123456789/40412022-12-07T18:14:44Z2021-11-01T00:00:00Zdc.title: Phase inversion prediction during the bulk synthesis of high-impact polystyrene: a fluid-dynamic approach
dc.contributor.author: Maffi, Juan M.; Estenoz, Diana
dc.description.abstract: "High-Impact Polystyrene (HIPS) is a heterogeneous material constituted by a rubber (PB) particles dispersed in a vitreous polystyrene (PS) matrix.
Two typical morphologies are usually identified: ‘salami’ (larger rubber particle with several PS occlusions) or ‘core-shell’ (smaller particle with one large occlusion). The industrial continuous bulk HIPS process involves four main stages: dissolution, pre-polymerization, finishing and evolatilization. During the pre-polymerization, the mixture consists of a continuous PB-rich phase where PS-rich droplets grow as the reaction proceeds. At a critical point, the dispersed vitreous phase reaches a volume such that it becomes the continuous phase, through a co-continuous transition. This is the phase inversion (PI) point, and the material morphology is essentially defined at this stage, characterized by a sudden drop in the mixture’s apparent viscosity."
2021-11-01T00:00:00Z