Influence of surfactants on a pre-adsorbed cationic layer: Removal and modification
Influence of surfactants on a pre-adsorbed cationic layer: Removal and modification
复制标题
表面活性剂对预吸附阳离子层的影响：去除和改性
DOI：
10.1016/j.jcis.2020.12.047
复制
发表时间：
2021
影响因子：
9.9
通讯作者：
Allen F
中科院分区：
文献类型：
--
作者：
Allen F
从固体表面去除有机物质是一个关键过程。使用带相反电荷的表面活性剂提供了一种增强去除的潜在方法。中子反射法已被用来调查的复杂行为的预吸附和坚韧的层的阳离子表面活性剂双十二烷基二甲基溴化铵（DDAB）在云母表面上，在暴露于不同的有机物种在溶液中。阴离子表面活性剂十二烷基硫酸钠（SDS）被证明能够去除阳离子层，但只有当阴离子胶束存在于溶液中。为了便于与非离子表面活性剂的行为进行比较，还研究了五甘醇单十二烷基醚（C12 E5）对云母的直接吸附;在临界胶束浓度及以上时观察到低表面覆盖吸附。然后发现C12 E5不去除阳离子层，但在一定程度上确实包含在层中。然而，阳离子表面活性剂在云母上的存在被示出显着地改变非离子表面活性剂的吸附行为。
Removal of organic species from solid surfaces is a crucial process. The use of oppositely charged surfactants provides a potential method for enhanced removal. Neutron reflectometry has been used to investigate the complex behaviour of a pre-adsorbed and tenacious layer of the cationic surfactant didodecyldimethylammonium bromide (DDAB) on a mica surface, during exposure to different organic species in solution. The anionic surfactant sodium dodecylsulfate (SDS) was shown to be able to remove the cationic layer, but only if anionic micelles were present in solution. To facilitate comparison with the behaviour of a non-ionic surfactant, the direct adsorption of pentaethylene glycol monododecyl ether (C12E5) to mica was also studied; low surface coverage adsorption was seen at the critical micelle concentration and above. C12E5was then found not to remove the cationic layer, but did include into the layer to some degree. The presence of cationic surfactant on the mica was however shown to significantly modify the adsorption behaviour of the non-ionic surfactant.