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dc.contributor.advisorBreedveld, Victor
dc.contributor.authorOh, Kyung Hee
dc.date.accessioned2015-09-21T15:51:23Z
dc.date.available2015-09-22T05:30:07Z
dc.date.created2014-08
dc.date.issued2014-05-06
dc.date.submittedAugust 2014
dc.identifier.urihttp://hdl.handle.net/1853/53992
dc.description.abstractThe spinning process of hollow fiber membranes was investigated with regards to two fundamental phenomena: flow (shear and elongation) and phase separation. Quantitative analysis of phase separation kinetics of binary (polymer/solvent) and ternary (polymer/solvent/volatile co-solvent) polymer solution was carried out with a newly developed microfluidic device. The device enables visualization of in situ phase separation and structure formation in controlled vapor and liquid environments. Results from these studies indicated that there was a weak correlation between phase separation kinetics and macroscopic defect (macrovoid) formation. In addition, the effect of shear and elongation on membrane morphology was tested by performing fiber extrusion through microfluidic channels. It was found that the membrane morphology is dominated by different factors depending on the rate of deformation. At high shear rates typical of spinning processes, shear was found to induce macrovoid formation through normal stresses, while elongation suppressed macroscopic defect formation. Furthermore, draw resonance, one of the key instabilities that can occur during fiber spinning, was investigated. It was found that draw resonance occurs at aggressive elongation condition, and could be suppressed by enhanced phase separation kinetics. These results can be used as guidelines for predicting hollow fiber membrane spinnability.
dc.format.mimetypeapplication/pdf
dc.language.isoen_US
dc.publisherGeorgia Institute of Technology
dc.subjectRheology
dc.subjectPolymer solutions
dc.subjectMembrane dopes
dc.subjectHollow fiber membrane spinning
dc.subjectPhase separation
dc.subjectMicrofluidics
dc.subjectFiber spinning instabilities
dc.titleEffect of shear, elongation and phase separation in hollow fiber membrane spinning
dc.typeDissertation
dc.description.degreePh.D.
dc.contributor.departmentChemical and Biomolecular Engineering
dc.embargo.terms2015-08-01
thesis.degree.levelDoctoral
dc.contributor.committeeMemberMeredith, Carson
dc.contributor.committeeMemberLu, Hang
dc.contributor.committeeMemberKoros, William J.
dc.contributor.committeeMemberBeckham, Haskell W.
dc.date.updated2015-09-21T15:51:23Z


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