Directed Pore Uptake and Phase Separation of Surfactant Solutions under Confinement
Directed Pore Uptake and Phase Separation of Surfactant Solutions under Confinement
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DOI：
10.1021/acs.jpcc.9b01522
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发表时间：
2019-03
期刊：
影响因子：
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通讯作者：
Yao Wu;Yingzhen Ma;Lilin He;G. Rother;W. Shelton;B. Bharti
中科院分区：
文献类型：
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作者：
Yao Wu;Yingzhen Ma;Lilin He;G. Rother;W. Shelton;B. Bharti
多孔材料吸收和释放分子的能力由孔隙空间中预吸附的表面活性剂的热力学状态决定。然而，对表面活性剂的热力学状态的空间限制的效果知之甚少。在这项研究中，我们使用的小角中子散射实验和全原子分子动力学模拟相结合，以开发一个更好地了解约束的自组装和温度诱导的表面活性剂溶液的液-液相分离的效果。在这里，我们研究了模型非离子表面活性剂三甘醇单己基醚（C6 E3）在SBA-15二氧化硅材料（孔径为8.6 nm）的管状纳米孔中的分层。我们发现，非离子型表面活性剂在二氧化硅孔中的原位聚集行为增强后，温度升高超过低临界溶解温度（LCST）。表面活性剂分子直接结合在孔壁上，起着后续吸附的锚作用，导致吸附过程中表面活性剂分子的迁移.
The ability of a porous material to uptake and release molecules is determined by the thermodynamic state of preadsorbed surfactants in pore space. However, the effect of spatial confinement on the thermodynamic state of the surfactants is poorly understood. In this study, we use a combination of small-angle neutron scattering experiments and all-atom molecular dynamics simulations to develop a better understanding of the effect of confinement on self-assembly and temperature-induced liquid–liquid phase separation of surfactant solutions. Here, we study the demixing of a model nonionic surfactant triethyleneglycol monohexyl ether (C6E3) in tubular nanopores of the SBA-15 silica material (pore diameter of 8.6 nm). We find that the nonionic surfactants show an enhanced in situ aggregation behavior in silica pores upon increasing the temperature above the lower critical solution temperature (LCST). The surfactant molecules directly bound to the pore walls act as anchor sites for subsequent adsorption, result...