Ramachandran S, Komura S, Seki K, Gompper G
Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Japan.
Eur Phys J E Soft Matter. 2011 May;34(5):46. doi: 10.1140/epje/i2011-11046-3. Epub 2011 May 11.
We present a Brownian dynamics theory with full hydrodynamics (Stokesian dynamics) for a Gaussian polymer chain embedded in a liquid membrane which is surrounded by bulk solvent and walls. The mobility tensors are derived in Fourier space for the two geometries, namely, a free membrane embedded in a bulk fluid, and a membrane sandwiched by the two walls. Within the preaveraging approximation, a new expression for the diffusion coefficient of the polymer is obtained for the free-membrane geometry. We also carry out a Rouse normal mode analysis to obtain the relaxation time and the dynamical structure factor. For large polymer size, both quantities show Zimm-like behavior in the free-membrane case, whereas they are Rouse-like for the sandwiched membrane geometry. We use the scaling argument to discuss the effect of excluded-volume interactions on the polymer relaxation time.
我们提出了一种适用于嵌入液膜中的高斯聚合物链的全流体动力学（斯托克斯动力学）布朗动力学理论，该液膜被本体溶剂和壁包围。针对两种几何结构，即在本体流体中嵌入的自由膜和夹在两壁之间的膜，在傅里叶空间中推导了迁移率张量。在预平均近似下，得到了自由膜几何结构中聚合物扩散系数的新表达式。我们还进行了劳厄正则模式分析以获得弛豫时间和动态结构因子。对于大尺寸聚合物，在自由膜情况下，这两个量都表现出类似齐姆的行为，而对于夹在中间的膜几何结构，它们表现出类似劳厄的行为。我们使用标度论证来讨论排除体积相互作用对聚合物弛豫时间的影响。
