聚乙二醇自组装单分子膜水润滑摩擦的分子动力学模拟  

Molecular Dynamics Simulation of Oligo(Ethylene Glycol) Self-Assembled Monolayers for Hydration Lubrication

作　　者：夏涛[1] 谭深 许楠 施耀[1] 何奕[1] 

机构地区：[1]浙江大学生物质化工教育部重点实验室,浙江大学化学工程与生物工程学院,浙江杭州310027

出　　处：《高校化学工程学报》2017年第6期1433-1441,共9页Journal of Chemical Engineering of Chinese Universities

基　　金：国家自然科学基金(21476191,21676245);国家重大研发计划(91434110)

摘　　要：聚乙二醇(PEG)不仅是一种典型的亲水抗污材料,其在水环境中还可表现出低摩擦特性。本研究采用分子动力学模拟考察了低聚乙二醇自组装单分子膜表面(OEG-SAM)之间水的结构、动态行为与摩擦的内在联系。结果表明,OEG-SAM水合层约为6?,可分为两层,每层中水的结构和动态行为与主体水存在显著差异。OEG-SAM表面间的摩擦系数与水合层厚度关系密切。当表面间距低于15?时,两表面的水合层直接接触,摩擦系数较高。当表面间距等于或大于15?时,两表面的水合层之间存在类似主体水层中的水,摩擦系数低。Poly （ethylene glycol） （PEG） is a typical non-fouling material and also exhibits low friction characteristics. In this work, molecular dynamics simulation was performed to investigate the innate relationship between structure/dynamics of water and friction within two oligo （ethylene glycol） self-assembled monolayer （OEG-SAM） surfaces. The results show that the OEG-SAM surface has a hydration layer with a thickness of-6 A, which can be divided into two sub-layers. The water in each sub-layer has different structure and dynamic characteristics when compared with bulk water. The friction between OEG-SAM surfaces is closely related to the thickness of the hydration layer. When the distance between the surfaces is less than 15 A, the direct contact of hydration layer leads to high friction. When the distance between the surfaces is equal to or larger than 15A, a bulk-water like layer forms, which leads to low friction.

关 键 词：聚乙二醇 摩擦 水润滑 分子动力学模拟 

分 类 号：O642[理学—物理化学]