(cont.) and filtration experiments, as well as other characterization techniques. Surface analysis is accomplished via x-ray photoelectron spectroscopy (XPS). Membrane samples are cleaned (in hydrogen peroxide or chromic-sulfuric acid (Chromerge)) and/or annealed (in 90⁰C deionized water), and their elemental surface composition and specific carbon binding environments are determined by XPS. Filtration experiments are done by alternating feed solutions of deionized water and a foulant (either bovine serum albumin or an oil/water emulsion). The flux of the feed solution is measured before fouling, during fouling, and after fouling, to determine the extent of fouling recovery. Also, the compositions of the permeates are analyzed via ultraviolet-visible spectroscopy to determine the rejection coefficient of the membrane. The data presented in this thesis show that PVDF blend membranes containing P(MMA-r-POEM) are capable of generating a fresh surface layer of PEO multiple times, even after extended cleaning sessions using concentrated acid. Membranes of varying thickness are shown to exhibit PEO-regenerative abilities, but it appears that thick membranes have better fouling recovery than thinner, filtration-series membranes. Also, it is found that a blend membrane stripped of all of its surface PEO (by a 24-hour-long exposure to Chromerge) is able to restore PEO to its surface with roughly 24 hours of annealing ...
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