Effects of excluded volume and hydrodynamic interaction on the deformation, orientation and motion of ring polymers in shear flow
Effects of excluded volume and hydrodynamic interaction on the deformation, orientation and motion of ring polymers in shear flow
复制标题
排除体积和流体动力相互作用对剪切流中环状聚合物变形、取向和运动的影响
DOI：
10.1039/c5sm00837a
复制
发表时间：
2015-01-01
期刊：
影响因子：
3.4
通讯作者：
An, Lijia
中科院分区：
文献类型：
--
作者：
Chen, Wenduo;Zhao, Hongchao;An, Lijia
环状聚合物是研究生物大分子行为的经典模型。与剪切流动中的线性聚合物相比，由于链端的缺失，环状聚合物对排斥体和流体动力相互作用更为敏感。采用多粒子碰撞动力学和分子动力学模拟相结合的方法，研究了排阻体积和流体动力相互作用对环状聚合物在剪切流动中行为的影响。结果表明，在没有较强排外体积相互作用的情况下，环状聚合物在流动梯度面上倾向于具有高变形和高取向的双链线性构象，罐踏运动几乎可以忽略不计。无排出体积的环状聚合物在变形、取向和滚滚运动的标度指数上与线形聚合物没有显著差异。我们还观察到流体动力相互作用可以有效地减缓环聚合物的松弛，而标度指数对Weissenberg数的影响很小。
A ring polymer is a classical model to explore the behaviors of biomacromolecules. Compared with its linear counterpart in shear flow, the ring polymer should be more sensitive to excluded volume and hydrodynamic interaction attributed to the absence of chain ends. We carried out multiparticle collision dynamics combined with molecular dynamics simulation to study the effects of excluded volume and hydrodynamic interaction on the behaviors of ring polymers in shear flow. The results show that in the absence of the strong excluded volume interaction, the ring polymer prefers a two-strand linear conformation with high deformation and orientation in the flow-gradient plane, and the tank-treading motion is nearly negligible. Ring polymers without excluded volume show no significant difference from linear polymers in the scaling exponents for the deformation, orientation and tumbling motion. We also observed that the hydrodynamic interaction could efficiently slow down the relaxation of ring polymers while the scaling exponents against the Weissenberg number have rarely been affected.