期刊
JOURNAL OF MOLECULAR LIQUIDS
卷 382, 期 -, 页码 -出版社
ELSEVIER
DOI: 10.1016/j.molliq.2023.121944
关键词
Molecular dynamics; Interfacial tension; Water; n-alkane interface; Oxyethylene and oxypropylene groups; Extended surfactant
In this study, the interfacial structure and dynamic property of six alkyl polyoxypropylene polyoxyethylene ether carboxylates at the water/oil interface were investigated using experiments and simulations. It was found that C12PO15EO5C reduced the interfacial tension to the order of 10-3 mN/m. The simulations showed that long PO chains curled in a helical shape and formed a compact arrangement, while short PO chains could not. Additionally, long EO chains partially laid flat on the interface and partially extended into the aqueous phase, bringing the hydrophilic oxygen atoms close to water molecules.
Extended surfactants including oxyethylene (EO) and oxypropylene (PO) groups have great potential applica-tions in the fields of oil recovery, separation and extraction, fabric washing, medicine and cosmetics vehicles. In this work, the interfacial structure and dynamic property of six alkyl polyoxypropylene polyoxyethylene ether carboxylates (C12POmEOnC, m = 5 and 15, n = 5, 10 and 15) at the water/oil interface were investigated with interfacial tension (IFT) experiments and molecular dynamics (MD) simulations. C12PO15EO5C was found to reduce the experimental IFT value to the order of 10-3 mN/m. Further, the interfacial thickness, stretch degree, hydrogen bond number and radial distribution function were calculated and analyzed in detailed simulations. The simulation results demonstrated that long PO chain curled in a helical shape to wrap hydrophilic oxygen atoms in the oil phase and reached a compact arrangement on the interface but short PO chain could not; long EO chain partially laid flat on the interface (about 5 EO units) and partially extended into the aqueous phase bringing the hydrophilic oxygen atoms close to water molecules while forming vacancies on the water side. Therefore, C12PO15EO5C had the tightest interfacial arrangement. Theoretical and experimental results are in fairly good agreement and they will provide enlightening insights into the design and synthesis of more effective extended surfactants.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据