芳基烷基磺酸盐链长对烷烃的油-水动态界面张力的影响

采用旋转滴法测定系列自制芳基烷基磺酸盐（C_nNPAS, n=8，10，12，14，16）水溶液对烷烃的油-水动态界面张力，考察了表面活性剂烷基链长、表面活性剂浓度、弱碱浓度、烷烃碳数等因素对油-水动态界面张力的影响。结果表明，增大C_nNPAS的烷基链长和碱含量均会使界面张力达到稳定值的时间增长；增加C_nNPAS浓度和烷烃碳数均会使界面张力动态变化加快，达到平衡所需时间减少。C_nNPAS表面活性剂可在低浓度范围较明显地降低界面张力，而随着浓度的增加界面张力回升明显。

Effects of carbon chain length on dynamic interfacial tension between alkane and aryl alkyl sulfonate aqueous solutions

Using spinning drop method, the interfacial tensions between alkane and series of aryl alkyl sulfonate(C_nNPAS, n=8,10,12,14,16)aqueous solutions were measured. The effects of the carbon number of alkane, the molecular weight of surfactant, the concentration of the surfactant and Na₂CO₃ on the interfacial tension were studied in detail. The results showed that the required time to reach the equilibrium interfacial tension increased with increasing molecular weight of the surfactant and content of Na₂CO₃. On the contrary, the higher carbon number of alkane and concentration of the surfactant, the less required time. The interfacial tension could be reduced obviously at a range of relative low surfactant concentrations, and then went through a minimum and eventually increased with increasing concentration.