Karalus Steffen, Janke Wolfhard, Bachmann Michael
Institut für Theoretische Physik, Universität Leipzig, Postfach 100 920, D-04009 Leipzig, Germany.
Phys Rev E Stat Nonlin Soft Matter Phys. 2011 Sep;84(3 Pt 1):031803. doi: 10.1103/PhysRevE.84.031803. Epub 2011 Sep 21.
We analyze the structural behavior of a single polymer chain grafted to an attractive, flexible surface. Our model is composed of a coarse-grained bead-and-spring polymer and a tethered membrane. By means of extensive parallel tempering Monte Carlo simulations it is shown that the system exhibits a rich phase behavior ranging from highly ordered, compact to extended random coil structures, and from desorbed to completely adsorbed or even partially embedded conformations. These findings are summarized in a pseudophase diagram indicating the predominant class of conformations as a function of the external parameters temperature and polymer-membrane interaction strength. By comparison with adsorption to a stiff membrane surface it is shown that the flexibility of the membrane gives rise to qualitatively new behavior such as stretching of adsorbed conformations.
我们分析了接枝到有吸引力的柔性表面上的单个聚合物链的结构行为。我们的模型由粗粒化的珠-弹簧聚合物和拴系膜组成。通过广泛的并行回火蒙特卡罗模拟表明,该系统表现出丰富的相行为,范围从高度有序、紧凑到伸展的无规线团结构,以及从解吸到完全吸附甚至部分嵌入的构象。这些发现总结在一个伪相图中,该图表明了作为外部参数温度和聚合物-膜相互作用强度函数的主要构象类别。通过与吸附到刚性膜表面的情况进行比较表明,膜的柔性会产生定性的新行为,如吸附构象的拉伸。