离子液体[BMim]BF_4对SDS水溶液表面活性和聚集能力的促进

Promotion of the Surface Activity and Aggregation Ability of Sodium Dodecylsulfate in Aqueous Solution by Ionic Liquid 1-butyl-3-methyl-imidazolium Tetrafluoroborate

采用表面张力测定法和核磁共振谱等方法研究了阴离子表面活性剂十二烷基硫酸钠(SDS)在水溶性室温离子液体[BMim]BF_4/水混合溶剂中的表面性质及聚集行为,发现极少量[BMim]BF_4的介入就可以显著降低SDS的临界胶束浓度,提高体系的表面活性;且[BMim]BF_4在混合溶剂中所占的摩尔分数(x_1)在一定范围内(0<x_1<0.0458)都能使SDS水溶液的表面活性和聚集能力提高:在x_1=0.0018时这种促进作用最强。

The surface property and aggregation behavior of an anionic surfactant, sodium dodecylsulfate （SDS）, in a mixed solvent of a water-soluble room temperature ionic liquid 1-butyl-3-methyl-imidazolium tetrafluoroborate （[BMim]BF4） and water were investigated by means of surface tension measurements and nuclear magnetic resonance （NMR） spectroscopy. It was found that the critical micelle concentration （cmc） of SDS could be remarkably reduced and the surface activity of the system was enhanced by the addition of a small amount of [BMim]BF4. Moreover, the surface activity and aggregation ability of SDS aqueous solution could be promoted when the molar fraction of [BMim]BF4 in the mixed solvent （x1） was at the range of 0-0.0458. This promotion function was most efficient at x1=0.0018.