Eric Fossum (Advisor), Daniel Ketcha (Committee Member), Kenneth Turnbull (Committee Member)
Master of Science (MS)
The synthesis of poly(arylene ether sulfone)s, with a pendant aryl iodide, was achieved via nucleophilic aromatic substitution (NAS) polycondensation of 3-iodo-3',5'-difluoro-diphenylsulfone (2) with Bisphenol-A. Monomer 2 was prepared by the reaction of 3, 5-difluorodiphenylsulfone with N-iodosuccinimide (NIS). Model reactions indicated that the iodo group was stable to NAS conditions. Both GC/MS analysis and NMR spectroscopy indicated quantitative displacement of the two fluorine atoms while the iodo group remained untouched. Furthermore, the modification of the iodo polymer was achieved via Suzuki-Miyaura cross-coupling reaction with phenyl, naphthyl, and phenylacetyl boronic acids. The thermal properties of the polymers were evaluated via DSC and TGA. The iodo polymer possessed a glass transition temperature, Tg, of 144 °C while the corresponding phenyl derivative displayed a slight decrease in Tg to 131 °C. The much bulkier naphthyl derivative provided a higher Tg of 150 °C. The more polar acetyl derivative showed a much higher Tg of 165 °C. All the polymers exhibited high Td-5% values between 400 °C and 500 °C. Moreover, conversion of the iodo moiety to an azide group was achieved by using sodium azide in a straightforward manner with the structure being confirmed by IR and NMR spectroscopies. In addition, the iodo group was replaced with a phenyl group, at the monomer stage, in order to prove that the system not only could be functionalized via "post" but also "pre" modification processes.
Department or Program
Department of Chemistry
Year Degree Awarded
Copyright 2012, all rights reserved. This open access ETD is published by Wright State University and OhioLINK.