A new approach to lamellar phases (Lα) in water -: non-ionic surfactant systems
A new approach to lamellar phases (Lα) in water -: non-ionic surfactant systems
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DOI：
10.1080/02678290310001628555
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发表时间：
2004-01-01
期刊：
影响因子：
2.2
通讯作者：
Schmidt, C
中科院分区：
文献类型：
--
作者：
Stubenrauch, C;Burauer, S;Schmidt, C
我们提出了两个不寻常的功能有关层状相（La）在二元水溶液中的非离子表面活性剂的新结果。第一个显著的特征是形成低至1重量%表面活性剂的高度稀释的L-α相，这已经在少量非离子表面活性剂中观察到，这些非离子表面活性剂都是烷基聚乙二醇醚（CiEj）类型。到目前为止，在二元H2O-CiEj系统中，已经报道了稀L-α相的存在或不存在。在后一种情况下，稀La相和浓La相总是连续连接的。然而，对于一种特定的硅烷表面活性剂，即（CH 3）（3）Si（CH 2）（6）（OCH 2CH 2）5 OCH 3，观察到两个不连续的L-α相。对二元H_2 O-C_（10）E_4体系和拟二元H_2 O-C_（10）E_4/C_（10）E_5体系的相行为进行了系统的研究，得出以下结论：（a）非离子表面活性剂的L-α相是其普遍特征;（B）非离子表面活性剂的L-α相和L-α相在结构上没有差别。我们提出了一种机制的L-α相的断开。
We present new results on two unusual features concerning lamellar phases ( La) in binary aqueous solutions of non-ionic surfactants. The first striking feature is the formation of highly dilute L-alpha phases down to 1 wt% of surfactant, which has been observed for a small number of non-ionic surfactants which are all of the alkyl polyglycol ether (CiEj) type. So far, in binary H2O - CiEj systems either the absence or the presence of a dilute L-alpha phase has been reported. In the latter case, the dilute and the concentrated La phase are always connected continuously. However, for one particular silane surfactant, namely (CH3)(3)Si(CH2)(6)(OCH2CH2) 5OCH3, two disconnected L-alpha phases were observed. Systematic investigations of the phase behaviour of the binary H2O - C10E4 system as well as of the pseudobinary H2O C10E4/ C10E5 systems enabled us to conclude that: (a) the disconnected L-alpha phase is a general feature of non-ionic surfactants and (b) there are no structural differences between the connected and the disconnected L-alpha phases. We propose a mechanism for the disconnection of the L-alpha phase.