Molecular dynamics simulation of cellulose-coated oil-in-water emulsions
Molecular dynamics simulation of cellulose-coated oil-in-water emulsions
复制标题
DOI：
10.1007/s10570-017-1290-1
复制
发表时间：
2017-07-01
期刊：
影响因子：
5.7
通讯作者：
Cohen, Yachin
中科院分区：
文献类型：
--
作者：
Miyamoto, Hitomi;Rein, Dmitry M.;Cohen, Yachin
通过分子动力学模拟研究了纤维素链和纤维素微晶在水包油乳剂中的行为，探讨了水包油乳剂中纤维素的包覆状态和结构特征。在水包油乳液中，分散的纤维素链在模拟过程中逐渐聚集，最终包围辛烷液滴。在纤维素微晶的情况下，位于晶体角落的纤维素链首先通过其疏水表面与辛烷液滴接触。沿着晶面的其他纤维素链逐渐向辛烷分子移动。在这两种乳液中，纤维素被发现与水和辛烷表面以特定的构象相互作用，使葡萄糖环的CH基团与辛烷分子接触，而这些环的OH基团与水分子接触形成氢键。辛烷液滴上的纤维素链也通过链间的横向氢键相互接触。这些相互作用稳定了纤维素分子作为表面活性剂形成的乳液。
The behaviors of cellulose chains and cellulose mini-crystal in oil-in-water emulsions were studied by molecular dynamics simulations to investigate the coating states and the structural features of cellulose in these emulsions. In oil-in-water emulsion, dispersed cellulose chains gradually assemble during the progress of the simulation, eventually surrounding the octane droplet. In case of a cellulose mini-crystal, the cellulose chain at the corner of the crystal first contacts with the octane droplet through its hydrophobic surface. The other cellulose chains along the crystal plane then gradually move toward the octane molecules. In both emulsions, the cellulose was found to interact with both water and octane surfaces with specific conformations that allow the CH groups of the glucose rings to contact with octane molecules, while the OH groups of these rings contact with water molecules to form hydrogen bonds. The cellulose chains on the octane droplet also contact with each other through lateral hydrogen bonding between chains. These interactions stabilize the emulsion formed by cellulose molecules as surfactants.