%0 Journal Article
%T <br>
%A 刘雪锋
%A 孔伟伟
%A 张永民
%A 郭爽
%J 物理化学学报
%D 2017
%R 10.3866/PKU.WHXB201702222
%X 硒，作为一种新的氧化-还原响应位点因其良好的生物相容性日益引起人们的关注，然而，对这种新型氧化-还原响应型表面活性剂的研究相对较少，尤其是其界面性能的智能调控。本文以含硒两性离子表面活性剂苄基十一烷基磺基甜菜碱（BSeUSB）为对象，研究了其分子结构、Krafft温度、表/界面张力及发泡和乳化性能的氧化-还原刺激响应行为。发现在极微量的H2O2（≤体系总质量的0.056%）氧化下，BSeUSB分子中疏水的-Se-C-键转变成了具有一定亲水能力的Se=O键，表面活性剂从单头单尾的还原态变成了类Bola型的氧化态，导致表面活性剂的Krafft温度由（23.5±0.5）℃下降至0℃以下，5.00 mmol·L-1时的表/界面张力分别从45.15、5.52 mN·m-1升高至61.63、18.38 mN·m-1。宏观上，还原态具有良好的发泡和乳化性能，而氧化态的发泡和乳化能力几乎消失。再次加入极少量还原剂Na2SO3（≤体系总质量的0.060%）后，分子的微观结构和溶液性能又可恢复到初始状态。总之，通过极微量H2O2和Na2SO3的交替加入，我们实现了该表面活性剂界面性能的智能调控。<br>Because of good biocompatibility using Se atom as the redox-responsive group has aroused considerable attention. However, only a few efforts have been devoted to Se-containing surfactant, especially for smart control of interfacial properties. This paper focuses on the redox-responsive behaviors of molecular structure, Krafft temperature, Surface/interfacial tension, foaming and emulsification of Se-containing zwitterionic surfactant, benzylselanyl-undecyl-dimethyl ammonium propane sulfonate (BSeUSB). The results show that after oxidization with a trace of H2O2 (≤0.056% of total mass), reduced form BSeUSB with one hydrophilic head and one hydrophobic tail transformed to Bola-type oxidized form BSeUSB-Ox due to the presence of a new hydrophilic group (selenoxide). And thus Krafft temperature decreased from (23.5±0.5)℃ to less than 0℃. The surface/interfacial tension at 5.00 mmol·L-1 increased from 45.15, 5.52 mN·m-1 to 61.63, 18.38 mN·m-1, respectively. Macroscopically, reduced form BSeUSB has good foaming and emulsification properties, while the foaming and emulsification abilities of oxidized form BSeUSB-Ox almost disappeared. Interestingly the molecular structure and the solution properties re-turned the initial states after reduction with a trace of Na2SO3 (≤0.060% of total mass). In a word, by the addition trace amounts of H2O2 and Na2SO3 alternately, we have achieved the smart control of the interfacial properties of the surfactant
%U http://www.whxb.pku.edu.cn/CN/Y2017/V33/I6/1205