1. Poly(ionic liquid) Nanolayers
Scott M. Husson, Department of Chemical and Biomolecular Engineering, Clemson University
Polymerized ionic liquids have excellent thermal resistance, high CO2 sorption capacities at low pressure, fast reversible adsorption/desorption, and exceptional selectivity for CO2 over permanent gases. These properties make pILs outstanding candidates as membrane separation layers for selective CO2 recovery from gas mixtures that are generated by combustion of fossil fuels.
Our approach uses surface-initiated atom transfer radical polymerization to produce highly uniform pIL nanolayers with controllable chain densities and independently controllable thicknesses. We have exploited this flexibility and control to systematically study how nanolayer structure, in addition to chemistry, affects CO2 sorption. One result is shown below that illustrates how grafting time is used to control nanolayer thickness at constant chain density. The pIL nanolayers, when grafted from a solid support, transform them into a CO2 selective sorbent. We also have measured CO2 adsorption isotherms for grafted pILs that vary in layer thickness and pIL anion (BF4-, CH3SO3-, CF3SO3-).
Growth of pIL nanolayers demonstrating that layer thickness can be controlled independently of chain density
Membrane support coated with pIL nanolayers adsorb CO2 with high selectively over N2