The Interactions Between Solvents of Casting Membrane Solution and Their Effects on Gas Permeability of EC Membrane

Casting membrane solution with more than two cpmponent solvents to increase remarably EC solubility is reported. Thus the option for EC solvents and concentration of casting solution could be improved. The interactions between solvent systems are charaterized through IR spectra shift of group and linkage of solvent molecules. It is considered that hydrogen bonds as well as electronic charge transfer between solvent molecules might be happened. Formamide, a strong polar solvent increase gas separation factor greatly of EC membrane, but decreases gas permeation. In addition, a third or forth solvent component mixed into a casting solution with two or three components will also be benifit to gas seperation of membranes, however decrease gas permeation.