Iyer Balaji V S, Lele Ashish K, Juvekar Vinay A
Complex Fluids and Polymer Engineering Group, Polymer Science and Engineering Division, National Chemical Laboratory, Pune 411008, India.
Phys Rev E Stat Nonlin Soft Matter Phys. 2006 Aug;74(2 Pt 1):021805. doi: 10.1103/PhysRevE.74.021805. Epub 2006 Aug 30.
We formulate a coarse-grained mean-field approach to study the dynamics of the flexible ring polymer in any given obstacle (gel or melt) environment. The similarity of the static structure of the ring polymer with that of the ideal randomly branched polymer is exploited in formulating the dynamical model using aspects of the pom-pom model for branched polymers. The topological constraints are handled via the tube model framework. Based on our formulation we obtain expressions for diffusion coefficient D, relaxation times tau, and dynamic structure factor g(k,t). Further, based on the framework we develop a molecular theory of linear viscoelasticity for ring polymers in a given obstacle environment and derive the expression for the relaxation modulus G(t). The predictions of the theoretical model are in agreement with previously proposed scaling arguments and in qualitative agreement with the available experimental results for the melt of rings.
我们制定了一种粗粒化平均场方法，以研究柔性环状聚合物在任何给定障碍物（凝胶或熔体）环境中的动力学。在使用支化聚合物的绒球模型的一些方面来制定动力学模型时，利用了环状聚合物的静态结构与理想随机支化聚合物的静态结构的相似性。通过管模型框架来处理拓扑约束。基于我们的公式，我们得到了扩散系数D、弛豫时间τ和动态结构因子g(k,t)的表达式。此外，基于该框架，我们为给定障碍物环境中的环状聚合物开发了一种线性粘弹性分子理论，并推导了弛豫模量G(t)的表达式。理论模型的预测与先前提出的标度论证一致，并且与环状聚合物熔体的现有实验结果在定性上一致。
