Simulations of a Grafted Dendritic Polyelectrolyte in Electric Fields
Simulations of a Grafted Dendritic Polyelectrolyte in Electric Fields
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DOI：
10.1021/ma502301a
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发表时间：
2015-01
期刊：
影响因子：
5.5
通讯作者：
J. Kłos;J. Sommer
中科院分区：
文献类型：
--
作者：
J. Kłos;J. Sommer
利用基于键涨落模型的Monte Carlo模拟，我们研究了在无热无盐溶剂中接枝在平板电容器电极上的带电树枝状聚合物的行为。在确定电荷之间的静电相互作用的强度和电极之间的电场的大小的参数范围很广的全库仑势的计算。对于低温和没有外部场的树枝状聚合物是在渗透制度，其中被捕获的抗衡离子的熵控制的分子的大小。增加场强度导致逐渐去除被定位在相对电极处的被捕获的抗衡离子。在位移场的阈值D* 处，所有抗衡离子从树枝状聚合物剥离，并且分子在电极上塌陷。树枝状大分子在垂直于电极方向上的延伸的崩溃是非常尖锐的，并且单体在电极中的双峰分布。
Using Monte Carlo simulations based on the bond fluctuation model, we study the behavior of a charged dendrimer grafted on one of the electrodes of a plate capacitor in an athermal, salt-free solvent. The calculations are performed for the full Coulomb potential in a wide range of parameters determining the strength of the electrostatic interactions between the charges and the magnitude of electric fields between the electrodes. For low temperatures and without an external field the dendrimer is in an osmotic regime where entropy of the trapped counterions controls the size of the molecule. Increasing the field strength leads to gradual removal of trapped counterions being localized at the opposite electrode. At a threshold value of the displacement field, D*, all counterions are stripped from the dendrimer, and the molecule is collapsed on the electrode. The collapse of the extension of the dendrimer in the direction perpendicular to the electrode is very sharp, and a bimodal distribution of monomers in ...