Stereocontrol Study in Radical Polymerization of 2-Acrylamido-2-methylpropane Sulfonic Acid in the Presence of Lewis Acids

摘要

Tacticity of poly-2-acrylamido-2-methylpropane sulfonic acid samples that were prepared via free radical polymerization in four different solvents, ethanol, dimethyl sulphoxide (DMSO), N, N-dimethylformamide (DMF) and water, were studied by 13C nuclear magnetic resonance (13C-NMR) techniques. In order to change isotacticity, two rare metal triflates, yttrium trifluoromethane sulfonate (Y(OTf)₃) and ytterbium trifluoromethane sulfonate (Yb(OTf)₃), were used. The stereoregularity of the obtained polymers in DMSO, water and DMF in the presence of the mentioned triflates did not show a noticeable alteration. But isotacticity of the samples prepared in ethanol was increased by about 17% in the presence 75 wt% Y(OTf)₃. In the absence of metal triflates, solvents did not have any significant effect on stereocontrol. In addition, the influence of temperature on isotacticity of the prepared samples was studied. By decreasing the reaction temperature, the isotacticity increased slightly.View full textDownload full textKeywordsTacticity, NMR, 2-acrylamodo-2-methylpropane sulfonic acid, Lewis acid, solvent effect, free radical polymerizationRelated var addthis_config = { ui_cobrand: "Taylor & Francis Online", services_compact: "citeulike,netvibes,twitter,technorati,delicious,linkedin,facebook,stumbleupon,digg,google,more", pubid: "ra-4dff56cd6bb1830b" }; Add to shortlist Link Permalink http://dx.doi.org/10.1080/10601325.2011.579813