In order to obtain some insight into the deformation behavior of the dispersed phase in the various flows and to evaluate the effects of various variables such as concentration of the dispersed phase and viscosity ratio, affine deformation equations were derived for some stratified shear and elongational flows. It was shown by the derived deformation equations that the volume fraction of the dispersed phase is a factor affecting the deformation of the dispersed phase, and the effect depends on viscosity ratio. The results from the stratified simple shear flow model predict that, for viscosity ratio >1, the deformation rate increases with the volume fraction, and the shear stress also increases, leading to the increase of the breakup time. Therefore, the total deformation of the dispersed phase, before breakup, increases with the increase of the volume fraction, resulting in the decrease of the size of the dispersed phase particles. The prediction was verified experimentally, in both the Haake batch mixer and the Couette flow mixer, using polyethylene/polyamide-6 blends compatibilized by adding maleic anhydride grafted polyethylene, when coalescence was suppressed. In the analysis of particle size data for the verification of the volume fraction effect, an effort was made to identify the contribution of coalescence. The experimental results of particle sizes in 1 wt% blends of the Haake mixer are in reasonable agreement with the transient deformation and breakup theory for simple shear flow. This suggests that the dominant flow in the mixer was shear flow. In some reactively compatibilized blends, at high shear rate, the particle sizes showed a maximum when either the weight fraction or the shear rate was increased. This behavior may be explained by coalescence effects related to the redistribution of the produced copolymers at the interface. It was shown experimentally that, for very high viscosity ratio (>3.5∼4), the deformation of large drops between gaps i
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.38471 |
| Date | January 2002 |
| Creators | Cho, Yong Gyun, 1965- |
| Contributors | Kamal, M. R. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Doctor of Philosophy (Department of Chemical Engineering.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001956453, proquestno: NQ85692, Theses scanned by UMI/ProQuest. |
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