Abstract: Seven magnetic ionic liquids of 1-methyl-3-alkylimidazolium tetrachloroferrate [Cnmim]FeCl4 (n=2, 4, 6, 8) and 1-methyl-3-butylimidazolium tetrahalogenoferrate [C4mim]FeX4 (X=Cl, Br) were synthesized and verified with 1H-NMR, Raman and MS spectra. [Cnmim]FeCl4 and [C4mim]FeBr4 had single anions, but [C4mim]FeClBr3 and [C4mim]FeCl3Br had multi-anions, including FeBr4-, FeBr3Cl-, FeCl2Br2-, FeCl3Br- and FeCl4-. The density, viscosity and conductivity of magnetic ionic liquids were measured. It was found that their densities were bigger than those of traditional ionic liquids, 1.25~1.94 g/cm3 at 25℃; viscosities were lower, 21~65 mPa×s at 25℃; conductivities were higher, 0.23~1.37 S/m at 30℃. The influences of temperature and structure of cations and anions on the above properties were extensively investigated.

Key words: magnetic ionic liquid, structure, density, viscosity, conductivity

摘要： 合成了4种1-甲基-3-烷基咪唑四氯化铁盐[Cnmim]FeCl4(n=2, 4, 6, 8)及3种1-甲基-3-丁基咪唑四卤化铁([C4mim]FeX4, X=Cl, Br)磁性离子液体，光谱结果表明，[Cnmim]FeCl4及[C4mim]FeBr4中阴离子单一，而[C4mim]FeClBr3及[C4mim]FeCl3Br中的阴离子为FeBr4-, FeBr3Cl-, FeCl2Br2-, FeCl3Br-, FeCl4-的混合物. 测定了其密度、粘度、电导率，磁性离子液体密度较大，25℃时为1.25~1.94 g/cm3；粘度较小，25℃时为21~65 mPa×s；电导率较大，30℃时为0.23~1.37 S/m. 并研究了其物性随温度及结构的变化规律.

关键词: 磁性离子液体, 结构, 密度, 粘度, 电导率