Sambasivam Abhinanden, Sangwai Ashish V, Sureshkumar Radhakrishna
Department of Biomedical and Chemical Engineering, Syracuse University, Syracuse, New York 13244, USA.
Intel Corporation, Hillsboro, Oregon 97124, USA.
Phys Rev Lett. 2015 Apr 17;114(15):158302. doi: 10.1103/PhysRevLett.114.158302.
Flow-induced configuration dynamics and scission of rodlike micelles are studied for the first time using molecular dynamics simulations in the presence of an explicit solvent and salt. Predicted dependence of tumbling frequency and orientation distribution on shear rate S agrees with mesoscopic theories. However, micelle stretching increases the distance between the cationic head groups and adsorbed counterions, which reduces electrostatic screening and increases the overall energy Φ linearly with micelle length. Micelle scission occurs when Φ exceeds a threshold value, independent of S.
首次在存在明确溶剂和盐的情况下，使用分子动力学模拟研究了流动诱导的棒状胶束的构型动力学和断裂。预测的翻滚频率和取向分布对剪切速率S的依赖性与介观理论一致。然而，胶束拉伸增加了阳离子头基与吸附的抗衡离子之间的距离，这降低了静电屏蔽并使总能量Φ随胶束长度线性增加。当Φ超过阈值时发生胶束断裂，与S无关。
