Graphene Oxide Embedded P(4-VP) Cryogel Composites for Fast Dye Removal/Separations

In this study, graphene oxide (GO) prepared via modified Hummers method was embedded within superporous poly(4-vinylpyridine) (p(4-VP)) cryogels during the p(4-VP) cryogel preparation up to 50 wt%. The SEM images revealed that GO layers are embedded within superporous of p(4-VP) network. The FT-IR and TGA analysis were also disclosed that the introduction of GO provided new functional groups and new thermal degradation profile for p(4-VP)/GO cryogel composites. The swelling of p(4-VP) and p(4-VP)/GO cryogel composites in different solvent demonstrated that the swelling properties of p(4-VP) cryogels were highly depend on the solvent and to the existence of GO. Moreover, bare p(4-VP) cryogel and p(4-VP)/GO cryogel composites were tested successfully in the direct removal of organic dyes such methylene blue (MB), rhodamine 6G (R6G), and methyl orange (MO) in aqueous environment. Interestingly, it was further illustrated that the separation of MB, R6G, and MO from their mixtures can be accomplished readily by using these cryogels as filter materials. The protonated forms of p(4-VP), p(4-VP)/GO that were obtained by HCl treatment of these cryogel systems were shown to be very successful in the separation of these dye mixtures. (C) 2016 Society of Plastics Engineers