Theander Katarina, Pugh Robert J
Institute for Surface Chemistry, Box 5607, S-114 86 Stockholm, Sweden.
J Colloid Interface Sci. 2003 Nov 1;267(1):9-17. doi: 10.1016/s0021-9797(03)00482-x.
The synergism and foaming behavior of a mixed surfactant system consisting of a nonionic surfactant (polyethoxylated alkyl ether C(n)E(m)) and a fatty acid soap (sodium oleate) were studied. The micellar interaction parameter (the beta-parameter) was determined from the cmc following the approach of Rubingh's regular solution theory. For both the C(12)E(6)/sodium oleate and the C(14)E(6)/sodium oleate mixtures, the results indicate a fairly strong attractive interaction (negative beta-values), which were in agreement with previous data reported for other nonionic/anionic surfactant systems. The characteristics of the foam produced from the surfactants were evaluated using a glass column equipped with a series of electrodes measuring the conductance of the foam, which enabled the water content of the foam to be determined. From these measurements, since the total foam volume was almost the same for all concentrations and surfactants, we compared the amount of liquid in the foam produced under dynamic foaming and the ability of the foam to entrain the liquid after the airflow was switched-off (static foam stability). The amount of liquid in the foam 100 s after the air was switched-off followed the order NaOl > C(12)E(6) > C(14)E(6). Also, the mixtures had the same foam volumes as the pure surfactants at the same concentration. However, both mixtures had higher concentrations of liquid in the foam when the mole fraction of the nonionic surfactant in the mixed surfactant system was greater than about >0.3 in the solution.
研究了由非离子表面活性剂（聚乙氧基化烷基醚C(n)E(m)）和脂肪酸皂（油酸钠）组成的混合表面活性剂体系的协同作用和发泡行为。根据鲁宾的正规溶液理论，通过临界胶束浓度（cmc）确定胶束相互作用参数（β参数）。对于C(12)E(6)/油酸钠和C(14)E(6)/油酸钠混合物，结果表明存在相当强的吸引相互作用（β值为负），这与先前报道的其他非离子/阴离子表面活性剂体系的数据一致。使用配备有一系列测量泡沫电导率的电极的玻璃柱评估表面活性剂产生的泡沫的特性，这使得能够确定泡沫的含水量。从这些测量中，由于所有浓度和表面活性剂的总泡沫体积几乎相同，我们比较了动态发泡下产生的泡沫中的液体量以及气流关闭后泡沫夹带液体的能力（静态泡沫稳定性）。气流关闭100秒后泡沫中的液体量顺序为NaOl > C(12)E(6) > C(14)E(6)。此外，在相同浓度下，混合物与纯表面活性剂具有相同的泡沫体积。然而，当混合表面活性剂体系中非离子表面活性剂的摩尔分数在溶液中大于约>0.3时，两种混合物在泡沫中的液体浓度更高。
