Polymer-solid contacts described by soft, coarse-grained models.
Polymer-solid contacts described by soft, coarse-grained models.
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DOI：
10.1039/c0cp02868a
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发表时间：
2011-05
期刊：
影响因子：
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通讯作者：
M. Müller;B. Steinmüller;K. Daoulas;A. Ramírez-Hernández;J. D. de Pablo
中科院分区：
文献类型：
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作者：
M. Müller;B. Steinmüller;K. Daoulas;A. Ramírez-Hernández;J. D. de Pablo
通过数值自洽场计算和蒙特卡罗模拟，探索了软的粗粒度模型描述几乎不可压缩的聚合物熔体与固体接触的窄界面的能力。我们通过定量比较不同珠数N但相同端到端距离R(E)的钢珠弹簧模型和连续高斯线模型的结果，研究了钢珠弹簧结构的离散性的影响。如果窄的聚合物-固体接触的宽度ξ小于或相当于统计段的长度b=R(E)/√N-1，则观察到两种模型在界面张力和密度分布方面的显著差异，并研究了补偿钢珠-弹簧模型的离散性质的策略。为了补偿钢珠弹簧模型中链条轮廓的离散化，我们同时调整了界面张力和密度分布，使之符合高斯线模型的预测。我们认为，聚合物-固体接触的几何形状和界面张力是聚合物-固体接触的粗粒度模型必须再现的相关特征，以便建立与实验系统的定量关系。
The ability of soft, coarse-grained models to describe the narrow interface of a nearly incompressible polymer melt in contact with a solid is explored by numerical self-consistent field calculations and Monte-Carlo simulations. We investigate the effect of the discreteness of the bead-spring architecture by quantitatively comparing the results of a bead-spring model with different number of beads, N, but identical end-to-end distance, R(e), and a continuous Gaussian-thread model. If the width, ξ, of the narrow polymer-solid contact is smaller or comparable to the length of a statistical segment, b=R(e)/√N-1, strong differences in the interface tension and the density profiles between the two models are observed, and strategies for compensating the discrete nature of the bead-spring model are investigated. Compensating the discretization of the chain contour in the bead-spring model by applying an external segment-solid potential, we simultaneously adjust the interface tension and the density profile to the predictions of the Gaussian-thread model. We suggest that the geometry of the polymer-solid contact and the interface tension are relevant characteristics that a coarse-grained model of polymer-solid contacts must reproduce in order to establish a quantitative relationship to an experimental system.