Romiszowski Piotr, Sikorski Andrzej
Department of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland.
J Chem Phys. 2006 Sep 14;125(10):104901. doi: 10.1063/1.2337627.
The aim of the study was a theoretical investigation of the polymer molecules located between two parallel and impenetrable surfaces which were also attractive for polymer segments. The chains were constructed of identical segments and were restricted to knots of a simple cubic lattice. Since the chains were at good solvent conditions the only interactions between the segments of the chain were the excluded volume. The properties of the model chains were determined by means of Monte Carlo simulations with a sampling algorithm based on the chain's local changes of conformation. The differences and similarities in the structure for different adsorption regimes and the size of the slit were shown and discussed. It was observed that at certain conditions the polymer chain was adsorbed at one of the confining surfaces, and then after a certain period of time it detached from this surface and approached the opposite wall; this switch was repeated many times. The influence of the strength of the adsorption, the size of the slit, and the chain's length on the frequency of these jumps were determined. The mechanism of the chain's motion during the switch was also shown.
该研究的目的是对位于两个平行且不可穿透表面之间的聚合物分子进行理论研究，这两个表面对聚合物链段也具有吸引力。链由相同的链段构成，并被限制在简单立方晶格的纽结中。由于链处于良溶剂条件下，链段之间唯一的相互作用是排除体积。通过基于链构象局部变化的采样算法进行蒙特卡罗模拟来确定模型链的性质。展示并讨论了不同吸附状态和狭缝尺寸下结构的差异与相似性。观察到在某些条件下，聚合物链吸附在其中一个限制表面上，然后经过一段时间后从该表面脱离并靠近相对的壁；这种切换会重复多次。确定了吸附强度、狭缝尺寸和链长对这些跳跃频率的影响。还展示了切换过程中链的运动机制。
