文献类型：期刊文献

英文题名：Molecular dynamics study of linear and comb-like polyelectrolytes in aqueous solution: effect of Ca2+ ions

作者：Tong, Kefeng[1];Song, Xingfu[1];Sun, Shuying[1];Xu, Yanxia[1];Yu, Jianguo[1]

机构：[1]E China Univ Sci & Technol, Sch Resources & Environm Engn, Natl Engn Res Ctr Integrated Utilizat Salt Lake R, Shanghai 200237, Peoples R China

年份：2014

卷号：112

期号：16

起止页码：2176

外文期刊名：MOLECULAR PHYSICS

收录：;EI(收录号：20143318073513);WOS:【SCI-EXPANDED(收录号:WOS:000340496600010)】；

语种：英文

外文关键词：molecular dynamics simulation; comb-like polyelectrolytes; Ca2+ tolerance; radius of gyration; pair correlations functions

摘要：All-atom molecular dynamics simulations were employed to provide microscopic mechanism for the salt tolerance of polyelectrolytes dispersants. The conformational variation of polyelectrolytes and interactions between COO- groups and counterions/water molecules were also studied via radius of gyration and pair correlations functions. Sodium polyacrylate (NaPA) and sodium salts of poly(acrylic acid)-poly(ethylene oxide) (NaPA-PEO) were selected as the representative linear and comb-like polyelectrolyte, respectively. The results show that Ca2+ ions interact with COO- groups much stronger than Na+ ions and can bring ion-bridging interaction between intermolecular COO- groups in the NaPA systems. While in the NaPA-PEO systems, the introduced PEO side chains can prevent backbone chains from ion-bridging interactions and weaken the conformational changes. The present results can help in selecting and designing new-type efficient polyelectrolyte dispersants with good salt tolerance.