Morphological Responsiveness of Anisotropic Partially Crystalline Emulsion Colloids
| Author(s) | Bayles, Alexandra | |
| Date Accessioned | 2013-10-09T18:53:49Z | |
| Date Available | 2013-10-09T18:53:49Z | |
| Publication Date | 2013-05 | |
| Abstract | Advancements in the synthesis of anisotropic colloids enable complex fluid systems to be designed with responsive properties. A capillary-based micromanipulation technique is developed to produce anisotropic droplets from the dispersed oil phase of partially crystalline emulsions. These particles have distinct non-spherical features with characteristic length to width aspect ratios ranging from 1 to 10. The particles demonstrate an ability to undergo sudden shape changes in response to changes in interfacial tension and temperature. During these deformation processes, the oil-water interface imposes a stress on the semi-crystalline network within each particle. When the imposed stress exceeds the critical stress of the crystalline material, the network yields and causes the particle to transition to a spherical shape. A model for morphological stability relating internal stress distributions to the interfacial Laplace pressure is developed to characterize this deformation. The analytical model captures qualitative trends observed in axisymmetric particle deformation, including the relationship between interfacial tension, crystalline content, characteristic size and regions prone to deformation. Through the development of a preliminary discrete modeling program, we lay the groundwork to quantitatively predict the deformation of experimental particles. Continued development of this modeling program will improve understanding of this system, and potentially provide product engineers with a tool to evaluate new particle shapes and emulsion environments. Continued experimental deformation, deposition, and material studies will reveal other modes of particle responsiveness and stimuli. Together, the experimental, theoretical and computational approaches begun here will advance the understanding of anisotropic partially crystalline emulsion particles and their use in enhanced deposition applications. | en_US |
| Advisor | Eric M. Furst | |
| Program | Chemical Engineering | |
| URL | http://udspace.udel.edu/handle/19716/12649 | |
| Language | en_US | en_US |
| Publisher | University of Delaware | |
| Title | Morphological Responsiveness of Anisotropic Partially Crystalline Emulsion Colloids | en_US |
| Type | Thesis | en_US |