archives@tulane.edu / Silicon-based block copolymers have gained prominence because of their inherent ability to self-assemble at the low molecular weight. By utilizing this vital factor, we synthesize poly(vinylmethylsiloxane-block-methyl methacrylate) (PVMS-b-PMMA) intending to create small characteristic features with the potential application for lithography and membrane filtration. The polymer is made by a combination of anionic synthesis of PVMS, ATRP (atom radical transfer polymerization) of PMMA, and then cojoining the end-group functionalized blocks with a “click” reaction. After synthesis, thin films (10-100 nm) were self-assembled to form structures aligned perpendicular to the substrate. The morphology was observed by atomic force microscopy, grazing incidence small-angle X-ray scattering (GISAXS), and transmission electron microscopy (TEM). Additionally, the hydrophobicity of PVMS prompted us to develop a coating on microporous membrane supports for separation of water-in-oil mixtures. The PVMS was used as an effective coating to prevent fouling while maintaining high selectivity for both water-in-toluene and water-in-decane emulsion in gravity-based filtration. Finally, cyclic block copolymers (BCPs) have garnered increased attention because of their unique structure, which differs from linear BCPs due to a lack of end groups. This feature in combination with the high segregation strength of silicon-based polymers is desirable for nanolithography. Thus, we synthesized a new class of silicon-based cyclic polymer, cyclic PVMS-b-PMMA, intending to later understand the impact of topology on phase behavior, domain spacing, and nanoconfinement in thin films. / 1 / Baraka Lwoya