两性离子/阴离子表面活性剂复配体系协同作用的研究

研究了阴离子表面活性剂十二烷基硫酸钠(SDS)和两性离子表面活性剂月桂酰胺丙基甜菜碱(LMB)的形成胶束能力和降低表面张力能力的协同增效作用。发现SDS和LMB质量比在7:3至3:7范围内增效作用显著。并考察了无机盐对表面活性剂复配体系泡沫性能的影响,结果表明,低浓度的无机盐会使表面活性剂复配体系表面张力和CMC下降,发泡力上升,高浓度的无机盐会使表面活性剂复配体系发泡力下降。例如0.1mol/L的NaCl使0.0025%的复配体系表面张力下降1.73mN/m,0.17mol/L的NaCl使2%的复配体系泡沫高度上升7.2%,而NaCl浓度超过0.26mol/L后会使泡沫高度降低。

Study of Cooperative Effect of Mixed System of Zwitterionic and Anionic Surfactants

The formation ability of micelle, the ability of reducing surface tension and foaming performance has been investigated for the mixed system of zwitterionic and anionic surfactant (Lauramidopropyl Betaine / Sodium Dodecyl Sulphate). The optimal surface activity was found when the mass fraction of Lauramidopropyl Betaine was about 3～7. The influence of salts on surface properties and foaming properties for the mixed system has been also studied. It was found that the surface activity was enhanced and the cmc values were reduced in this system. The foamability of this system will be reduced when salts were applied at higher concentration. For instance, surface tension of mixed system (0.0025%) was reduced 1.73 mN / m in the presence of 0.1 mol/L of NaCl. and foamability were increase 7.2% in the presence of 0.17 mol/L of NaCl. Exceptionally foaming properties become worse when the concentration of NaCl was higher than 0.26 mol/L.