| Recent awareness and concern for the release of toxic waste into the environment have placed demands on the chemical industry for cleaner processes that generate less toxic waste. Ionic liquids are solvent alternatives to the volatile organic compounds currently being used. They are virtually non-volatile, non-flammable, recyclable materials that are liquids at or near room temperature and dissolve a wide range of organic and inorganic compounds, making them ideal as alternative reaction solvents. In addition, they have been proposed as new types of electrolytes for batteries owing to their high electrical conductivity. They have also been investigated for a myriad of other applications including separations, liquid/liquid extraction, industrial cleaning, fuel cells, heat transfer fluids and lubricants.; The present work describes the preparation and properties of two new types of ionic liquids based on polyammonium cations with different anions.; Liquid Ionic Phosphates (LIPs) contain the simple phosphate (PO 43−) anion, whereas Polyammonium Ionic Liquid Sulfonamides (PILS) bear the bis(trifluoromethanesulfonyl)imide [(CF3SO 2)2N−] anion. LIPs are hydrophilic whereas PILS are hydrophobic illustrating the “designer solvent” description of ionic liquids.; Wherever possible it has been attempted to employ “greener” synthetic methods, such as solvent free reactions, for the preparation of these new species.; Volumetric Karl Fischer Titration was used to measure residual water content. Samples containing less than 1.0% water were characterized further. Specific conductivity was measured using a YSI conductivity bridge with a dip-type probe. Conductivities on the order of 10−1–10 1 mS/cm were obtained for LIPs and PILS. Self diffusion coefficients were determined using Pulse gradient spin echo NMR and were found to be on the order of 10−8–10−7 cm 2/s for both anions and cations. Electrochemical windows were determined using cyclic voltammetry and ranged from 2.1–4.4 V. Densities ranged from 0.99 g/mL–2.0 g/mL. LIPs were found to be miscible with solvents such as methanol and water and PILS with ethylacetate, acetone and acetonitrile. Pulse radiolysis studies indicated that the solvated electron in hydroxyl substituted PILS behave similar to that in ethanol.; These results suggest that LIPs and PILS may have applications in batteries and as other types of electrochemical media. LIPs are particularly cost effective. |
