阳离子对阴离子型表面活性剂影响的分子模拟研究  

Molecular Simulation Studies of the Cation Influences on Properties of Anionic Surfactant Solution

作　　者：孟思炜 张劲[2] 周广刚[1] 刘兵[2] 肖丽佳[2] 陈鹏峰[2] 卢贵武[1] 

机构地区：[1]中国石油大学(北京)理学院,北京102249 [2]中国石油大学(北京)石油工程学院,北京102249

出　　处：《内蒙古师范大学学报（自然科学汉文版）》2015年第1期57-61,共5页Journal of Inner Mongolia Normal University(Natural Science Edition)

基　　金：国家科技重大专项"大型油气田及煤层气开发"(2011ZX05062-003);国家"973"煤层气项目"提高煤层气开采效率的煤储层改造基础研究"(2009CB219607);中国石油大学(北京)基础学科研究基金(01JB0169)

摘　　要：使用密度泛函理论,在B3LYP/6-31G水平上,对十二烷基磺酸盐阴离子表面活性剂与阳离子(K+)形成的离子对进行结构优化,得到稳定的几何构型,进而从分子水平研究阴离子表面活性剂与阳离子之间的相互作用.计算结果表明,阳离子与表面活性剂的氧原子形成稳定离子构型,与阳离子结合后表面活性剂的极性头电荷减少从而降低了极性头间的排斥作用.进而利用介观层次的耗散粒子动力学,研究了阳离子加入对表面活性剂溶液体系表面张力的影响,结果表明,阳离子可显著降低阴离子型表面活性剂的临界胶束浓度,并提高其降低表面张力的效率.In this paper,the structure of the ion pair of dodecyl sulfonate with cations （K＋ ）was opti-mized by using Density Function Theory（DFT）at the B3LYP/6-31G level to get geometrical structure. The interactions between surfactants and cations were studied at the molecular level.The results show that several oxygen atoms binding with one cation is stable.After binding,the charge of the polar heads decrea-ses,thus decrease the repulsion effect between head groups.We further apply dissipative particle dynamics （DPD）method to investigate the effect of cations on surface tension of surfactant solution.It is found that the presence of cations decreases the critical micelle concentration （CMC）of anionic surfactants and enhances the efficiency on decreasing solution’s surface tension.

关 键 词：阴离子表面活性剂 密度泛函理论 耗散粒子动力学 电荷分布 临界胶束浓度 

分 类 号：O647.2[理学—物理化学]