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Primary amines form a key component of a well-studied mechanism for capturing carbon dioxide (CO 2 ) from the atmosphere. This study comprises a single-step synthesis of a novel sorbent for CO 2 by grafting monomers rich in primary amines to three commercial-grade fabrics: polyethylene terephthalate, high-density polyethylene and nylon 6. An initial evaluation of the sorbency of the chosen monomers, allylamine and butenylamine, qualitatively confirmed their ability to extract CO 2 from the atmosphere. Six novel copolymers, comprised of each of the three fabrics grafted with one of each monomer, were synthesized using radiation-induced graft copolymerization through electron beam irradiation. All fabrics achieved greater grafting with butenylamine compared to allylamine, likely given the closer proximity of the primary amine to the radical on the latter's structure. Primary amines can stabilize radicals, preventing copolymerization reactions. Characterization of sorbency revealed that the majority of the grafted amines likely reacted to adsorb CO 2 . Therefore, the amount of amine grafted comprises the primary limiting factor on the sorbents' CO 2 capacity.

In order to test the effectiveness of oxalate-based polymeric adsorbents in the recovery of uranium from seawater, diallyl oxalate (DAOx) was grafted onto nylon 6 fabrics by exposing the fabric, immersed in pure liquid DAOx or in a surfactant-stabilized dispersion of DAOx in water, to electron beam or gamma radiation. Following drying and weighing to determine the degree of grafting (DoG), the presence of oxalate in the fabrics was verified using XPS. Zeta potential measurements showed the fabric surfaces to be negatively charged. The fabrics were tested by rotating them for 7 days in a rotary agitator with actual seawater spiked with 0.2 or 1.0 mg∙L -1 uranium. The fraction of uranium in the solution which was removed due to uptake on the fabrics was found to rise with increasing DoG at both uranium concentrations. EDS measurements were used to map the distribution of adsorbed uranium on the polymeric fibers.