,Molecular dynamics simulation of the response of bi-disperse polyelectrolyte brushes to external el

• 作 者: Fen Zhang Huan-Da Ding Chao Duan Shuang-Liang Zhao Chao-Hui Tong
• 机 构: Department of Physics, Ningbo University, Ningbo 315211, China“,”College of Chemical Engineering, Ea
• 出 处: 中国物理B（英文版）
• 发表日期: 2017年8期
• 关键词: polyelectrolyte brushes electric fields polydispersity molecular dynamics

Langevin dynamics simulations have been performed to investigate the response of bi-disperse and strong polyacid chains grafted on an electrode to electric fields generated by opposite surface charges on the polyelectrolyte (PE)-grafted electrode and a second parallel electrode.Simulation results clearly show that,under a negative exteal electric field,the longer grafted PE chains are more strongly stretched than the shorter ones in terms of the relative change in their respective brush heights.Whereas under a positive exteal electric field,the grafted shorter chains collapse more significantly than the longer ones.It was found that,under a positive exteal electric field,the magnitude of the total electric force acting on one shorter PE chain is larger than that on one longer PE chain,or vice versa.The effects of smeared and discrete charge distributions of grafted PE chains on the response of PE brushes to exteal electric fields were also examined.