COLL 235 |
| One of the primary processes for making fluoropolymers is aqueous dispersion/emulsion polymerization of fluoroolefins which uses fluorosurfactants, especially perfluorooctanoic acid (PFOA), as dispersants. According to the EPA's 2010/15 PFOA Stewardship Program, participating companies will eventually eliminate the use and emission of PFOA by 2015. This demands more environmentally benign alternative surfactants and corresponding processes or modification of current processes. Conventional hydrocarbon surfactants have long been considered to be improper as dispersants in polymerization of fluoroolefins due to their considerablly high chain transfer constants and relatively poor compatibility to fluoropolymers. In our search of alternative processes of making fluoropolymers, we screened a variety of non-PFOA surfactants in conventional dispersion/emulsion polymerization process among which some gave promising results. Some factors affecting dispersion percent solids, particle sizes, size distributions and particle morphologies were studied. Concentration of the virgin dispersions into fluoropolymer latexes with high percent solids was also studied. Our results and current progress in this field will be discussed in detail. |
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Fundamental Research in Colloid and Surface Chemistry
6:00 PM-8:00 PM, Monday, August 20, 2007 BCEC -- East Registration, Poster
Division of Colloid & Surface Chemistry |