Penfold J, Tucker I, Thomas R K, Taylor D J F, Zhang J, Bell C
ISIS, Rutherford Appleton Laboratory, CCLRC, Chilton, Didcot, OXON, UK.
Langmuir. 2006 Oct 10;22(21):8840-9. doi: 10.1021/la061319l.
The polyelectrolyte poly(ethylenenimine), PEI, is shown to strongly influence the adsorption of the anionic-nonionic surfactant mixture of sodium dodecyl sulfate, SDS, and monododecyl hexaethylene glycol, C(12)E(6), at the air-solution interface. In the presence of PEI, the partitioning of the mixed surfactants to the interface is highly pH-dependent. The adsorption is more strongly biased to the SDS as the pH increases, as the PEI becomes a weaker polyelectrolyte. At surfactant concentrations >10(-4) M, the strong interaction and adsorption result in multilayer formation at the interface, and this covers a more extensive range of surfactant concentrations at higher pH values. The results are consistent with a strong interaction between SDS and PEI at the surface that is not predominantly electrostatic in origin. It provides an attractive route to selectively manipulate the adsorption and composition of surfactant mixtures at interfaces.
聚电解质聚乙烯亚胺（PEI）被证明会强烈影响十二烷基硫酸钠（SDS）和单十二烷基六乙二醇（C(12)E(6)）的阴离子-非离子表面活性剂混合物在气-液界面的吸附。在PEI存在的情况下，混合表面活性剂在界面的分配高度依赖于pH值。随着pH值升高，由于PEI成为较弱的聚电解质，吸附更强烈地偏向SDS。在表面活性剂浓度>10^(-4) M时，强烈的相互作用和吸附导致在界面形成多层结构，并且在较高pH值下，这涵盖了更广泛的表面活性剂浓度范围。结果与表面上SDS和PEI之间的强相互作用一致，这种相互作用主要不是源于静电作用。它为选择性地控制界面处表面活性剂混合物的吸附和组成提供了一条有吸引力的途径。
