文献类型：期刊文献

英文题名：Salt effects on knot dynamics in polyelectrolyte solutions

作者：Gao, Xiangxiang[1];Xu, Xiaofei[2,3]

机构：[1]Soochow Univ, Ctr Soft Condensed Matter Phys & Interdisciplinar, Suzhou, Jiangsu, Peoples R China;[2]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai, Peoples R China;[3]East China Univ Sci & Technol, Sch Chem Engn, Shanghai, Peoples R China

年份：2022

卷号：48

期号：4

起止页码：273

外文期刊名：MOLECULAR SIMULATION

收录：;EI(收录号：20215111368117);WOS:【SCI-EXPANDED(收录号:WOS:000734353400001)】；

基金：This work was supported by the National Natural Science Foundation of China [grant numbers 21978079 and 21674077.

语种：英文

外文关键词：Salt effects; knot dynamics; single chain dynamics; coil-to-globule transition

摘要：We study the dynamics of linear polyelectrolyte (PE) knot in solution with doping salt by molecular dynamics simulations. The molecular mechanisms of PE knot dynamics are explained. The knot dynamics are the coupling results by the moving effect of chain entanglement and by the breathing effect of knot fluctuations. The moving effect is important as the whole chain is in the random coil state and becomes weak as shrinking to the close-to-globule (CTG) state. Interestingly, as the chain in the CTG state, the knot swells with occupying more segments. The breathing effect dominates the knot dynamics in the CTG state. This nontrivial behaviour (in comparison to neutral polymer knot) is prominent for the cases of doping salt with high concentration or of doping high-valent salt, which attributes to the enhanced electrostatic interactions and long-range fluctuation effects.