Department of Chemical Engineering, University of Texas at Austin, Austin, Texas 78712, USA.
Soft Matter. 2018 May 16;14(19):3748-3759. doi: 10.1039/c8sm00298c.
We study the structural characteristics of a system of charged nanoparticles in a neutral polymer solution while accounting for the differences in the dielectric constant between the particles, polymer and the solvent. We use a hybrid computational methodology involving a combination of single chain in mean-field simulations and the solution of the Poisson's equation for the electrostatic field. We quantify the resulting particle structural features in terms of radial distribution function among particles as a function of the dielectric contrast, particle charge, particle volume fraction and polymer concentration. In the absence of polymers, charged macroions experience increased repulsion with a lowering of the ratio of particle to solvent dielectric constant. The influence of the dielectric contrast between the particle and the solvent however diminishes with an increase in the particle volume fraction and/or its charge. In the presence of neutral polymers, similar effects manifest, but with the additional physics arising from the fact that the polymer-induced interactions are influenced by the dielectric contrast of the particle and solvent.
我们研究了在中性聚合物溶液中带电纳米粒子系统的结构特征，同时考虑了粒子、聚合物和溶剂之间介电常数的差异。我们使用了一种混合计算方法，结合了平均场模拟的单链和泊松方程解以求解静电场。我们根据粒子之间的径向分布函数来量化粒子的结构特征，作为介电对比度、粒子电荷、粒子体积分数和聚合物浓度的函数。在没有聚合物的情况下，带电荷的大分子离子随着粒子与溶剂介电常数之比的降低而受到更大的排斥。然而，随着粒子体积分数和/或其电荷的增加，粒子与溶剂之间的介电对比度的影响会减弱。在存在中性聚合物的情况下，会出现类似的效果，但由于聚合物诱导的相互作用受到粒子和溶剂介电对比度的影响，因此会出现额外的物理现象。
