Chen Cangyi, Tang Ping, Qiu Feng, Shi An-Chang
The State Key Laboratory of Molecular Engineering of Polymers, Key Laboratory of Computational Physical Sciences, Department of Macromolecular Science, Fudan University, Shanghai 200433, China.
Department of Physics and Astronomy, McMaster University, Hamilton, Ontario L8S 4M1, Canada.
J Chem Phys. 2015 Mar 28;142(12):124904. doi: 10.1063/1.4916133.
A classical density functional theory (DFT) is applied to investigate the behavior of compressed polymer brushes composed of hard-sphere chains. The excluded volume interactions among the chain segments are explicitly treated. Two compression systems are used to study the behavior of brush-wall and brush-brush interactions. For the brush-brush systems, an obvious interpenetration zone has been observed. The extent of the interpenetration depends strongly on the grafting density. Furthermore, the repulsive force between the brush and wall or between the two brushes has been obtained as a function of the compression distance. Compared to the prediction of the analytic self-consistent field theory, such force increases more rapidly in the brush-wall compression with high polymer grafting densities or at higher compressions. In the brush-brush compression system, the interpenetration between the two compressed brushes creates a "softer" interaction. The influence of hard-sphere solvents on the behavior of compressed brushes is also discussed.
应用经典密度泛函理论（DFT）来研究由硬球链组成的压缩聚合物刷的行为。明确考虑了链段之间的排斥体积相互作用。使用两种压缩系统来研究刷-壁和刷-刷相互作用的行为。对于刷-刷系统，观察到一个明显的相互渗透区。相互渗透的程度强烈依赖于接枝密度。此外，已获得刷与壁之间或两个刷之间的排斥力作为压缩距离的函数。与解析自洽场理论的预测相比，在高聚合物接枝密度或更高压缩下的刷-壁压缩中，这种力增加得更快。在刷-刷压缩系统中，两个压缩刷之间的相互渗透产生了一种“更软”的相互作用。还讨论了硬球溶剂对压缩刷行为的影响。
