聚乙二醇与十二烷基羟丙基磺基甜菜碱相互作用的介观动力学模拟

Mesoscopic simulation study on the interaction of polyethylene glycol and dodecyl hydroxypropyl sulfobetaine

采用介观动力学(MesoDyn)模拟方法研究了聚乙二醇(PEG)与十二烷基羟丙基磺基甜菜碱(DSB)在水溶液中的聚集行为,从介观层次上探讨了PEG以及与DSB混合体系的聚集过程和聚集形态,并对混合体系中DSB的体积分数、温度和剪切速率等影响因素进行了分析。实验结果表明,PEG在水溶液中随体积分数增加会形成球形、棒状、蠕虫状聚集体和网状结构;PEG与表面活性剂DSB之间存在着较强的协同作用,在较低的DSB体积分数下PEG即可产生聚集现象;随着温度的增加,PEG/DSB混合体系聚集变得较为困难,而且聚集的速度也逐渐变慢,说明整个聚集过程是放热的;并且剪切作用对体系聚集行为影响较大。

Aggregation behavior of aqueous solution of polyethylene glycol （PEG） and dodecyl hydroxypropyl sulfobetaine （DSB） using mesoscopie dynamic （MesoDyn） simulation method. The process of aggregate formation and the aggregate morphology of PEG and PEG/DSB blend system were discussed at mesoscopie level. Effects of factors such as DSB volume fraction, temperature and shear rates et al on the aggregation were examined. Results indicated that, following the increase of volume fraction of PEG the aggregate morphology of PEG in aqueous solution would change as spherical aggregate, rodlike aggregate, worm -like aggregate and network structure. There is rather strong synergic effect between PEG and surfaetant DSB, and PEG would aggregate with a low volume fraction of DSB. As temperature rises, the aggregation of PEG/DSB blend system becomes difficult and the rate of aggregation becomes slow. It indicated that the aggregation process is exothermic. The shear action shows quite big effect on aggregation behavior.