Polyelectrolytes in Analytical Separations

• Other Authors: Howell, Peter B. (authoraut)
• Format: Others
• Language: English; English
• Published: Florida State University
• Subjects: Chemistry
• Online Access: http://purl.flvc.org/fsu/fd/FSU_migr_etd-3709

Block copolymer ionomers are a class of polymers that contain a hydrophobic block and a block containing charged repeat units. In the first set of experiments, micelles were created from such a polymer. A set of fluorescence probe measurements revealed that the critical micelle concentration for this polymer was O.3ppm. Unfortunately, the fluorescence probe technique assumes an infinite partition coefficient. A mathematical analysis of the technique was performed which revealed that the finite partition coefficient of the probe molecule results in a background, which accounts for all of the response. A capillary electrophoresis experiment was developed which demonstrated that the micelles do not dissociate, even at infinite dilution. In a second set of experiments, polyelectrolytes were used as a stationary phase for capillary electrochromatography. Nonporous particles were coated with alternating layers of poly(diallyldimethylammonium) and poly(styrene sulfonate). Weak retention was demonstrated, with hydrogen bonding as the predominant mechanism. In the last set of experiments, a capillary was coated with polyelectrolyte under electroosmotic flow. To a first approximation, this procedure should fail, but a more detailed model was developed which predicted that the procedure is possible. A procedure was created to measure the velocity inside the capillary throughout the coating process, and a computer model was developed that could provide qualitatively similar results to the experiments. The model also predicted that removal of the buffer from the solution in the capillary would accelerate the process by an order of magnitude. This was later shown experimentally. === A Dissertation submitted to the Department of Chemistry in partial fulfillment of the requirements for the degree of Doctor of Philosophy. === Fall Semester, 2002. === December 13, 2001. === Analytical Separations, Polyelectrolytes === Includes bibliographical references. === Joseph B. Schlenoff, Professor Directing Dissertation; David van Winkle, Outside Committee Member; John G. Dorsey, Committee Member; Oliver Steinbock, Committee Member.