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In recent decades, the increased use of polyvinyl chloride (PVC) in industries and households has led to a surge in PVC waste pollution, which mandates developing solutions for the removal of waste PVC from the environment. We report upcycling, the conversion of waste material to a high-value-added product, of PVC-based products to electrospun (ES) fibers (mats). As two common PVC products, waste PVC pipe and waste PVC pool float were upcycled to ES fibers for water treatment. The fabrication process and fiber characteristics, such as morphology, surface charge, and mechanical strength of upcycled fibers, were studied and compared with the same fibers fabricated using research-grade (RG) PVC (commercial PVC powder). In addition, the effect of additives such as calcium carbonate in PVC waste products on the physicochemical properties of upcycled fibers was evaluated. The results showed that upcycling of waste PVC to ES fibers is feasible since the upcycled fibers showed similar or superior properties compared to their equivalent fibers from RG-PVC. Finally, the performance of upcycled fibers on the removal of dyes from the water was evaluated. The upcycled fibers from waste PVC pipes and pool float outperformed the RG PVC fibers in removing methylene blue from water by showing more than 97% removal efficiency. In addition, the upcycled PVC ES fibers showed more than 80% reusability after five adsorption−desorption cycles. 

N-Sulfonyl-activated aziridines are known to undergo anionic-ring-opening polymerizations (AROP) to form polysulfonyllaziridines. However, the post-polymerization deprotection of the sulfonyl groups from polysulfonyllaziridines remains challenging. In this report, the polymerization of tert-butyl aziridine-1-carboxylate (BocAz) is reported. BocAz has an electron-withdrawing tert-butyloxycarbonyl (BOC) group on the aziridine nitrogen. The BOC group activates the aziridine for AROP and allows the synthesis of low-molecular-weight poly(BocAz) chains. A 13C NMR spectroscopic analysis of poly(BocAz) suggested that the polymer is linear. The attainable molecular weight of poly(BocAz) is limited by the poor solubility of poly(BocAz) in AROP-compatible solvents. The deprotection of poly(BocAz) using trifluoroacetic acid (TFA) cleanly produces linear polyethyleneimine. Overall, these results suggest that carbonyl groups, such as BOC, can play a larger role in the in the activation of aziridines in anionic polymerization and in the synthesis of polyimines. 

With NSF MRI support, we have recently purchased a dual source single crystal diffractometer equipped with a high resoln. detector.  The purpose of this presentation is to publicize the new instrument and we seek users in the Southeast to maximize the pos. impact of this instrument on research efforts in the Southeastern US.  Users at primarily undergraduate institutions and historically black colleges and universities are particularly encouraged to use this new resource.  In general, an X-ray diffractometer allows accurate and precise measurements of the full three-dimensional structure of a mol., including bond distances and angles, and provides accurate information about the spatial arrangement of a mol. relative to neighboring mols.  The studies described here impact many areas, including org. and inorg. chem., materials chem. and biochem.  This instrument is an integral part of teaching as well as research and research training of graduate and undergraduate students in chem. and biochem. at this institution and at partner institutions.  This poster will describe some examples of how the new diffractometer will enhance research in inorg. chem., materials chem. (via diffuse scattering), and biochem.