A comparative study of semi-flexible linear and ring polymer conformational change in an anisotropic environment
A comparative study of semi-flexible linear and ring polymer conformational change in an anisotropic environment
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各向异性环境下半柔性线型和环状聚合物构象变化的比较研究
DOI：
10.1039/c9cp07018d
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发表时间：
2020
影响因子：
3.3
通讯作者：
Zhao Nanrong
中科院分区：
文献类型：
--
作者：
Chen Anpu;Zhang Bingjie;Zhao Nanrong
我们采用基于朗之万动力学的模拟来系统地研究半柔性探针聚合物在棒拥挤环境中的构象变化。特别考虑了两种拓扑不同的探测聚合物类型，线性聚合物和环状聚合物。我们的结果揭示了所探测聚合物的半柔性和拥挤各向异性之间相互作用的重要性。首先，随着刚度的增加，环状和线性聚合物都表现出不平凡的尺寸变化，包括非单调性和塌陷-膨胀交叉。其次，我们调节杆拥挤器长度来研究各向异性效应。我们发现，环境的有序平行排列的形成可以有效地对所探测的聚合物产生显着的拉伸效应。拥挤各向异性引起的拉伸与聚合物刚度之间的耦合可以解释不寻常的溶胀行为。最后，分析了环状聚合物的非单调溶胀和形状变化。我们发现环聚合物在坚固的刚度下会受到最明显的溶胀。此外，在相同的鲁棒位置也观察到了最大的扁长形状。
We adopt a Langevin-dynamics based simulation to systematically study the conformational change of a semi-flexible probed polymer in a rod crowding environment. Two topologically different probed polymer types, linear and ring polymers, are specifically considered. Our results unravel the significance of the interplay of probed polymer's semi-flexibility and crowding anisotropy. Firstly, both ring and linear polymers show a non-trivial dimensional change including nonmonotonicity and collapse–swelling crossover as their stiffness increases. Secondly, we modulate rod crowder length to investigate the anisotropic effect. We reveal that the formation of an ordered parallel arrangement of the environment can effectively lead to a remarkable stretching effect on the probed polymer. The coupling between the crowding anisotropy-induced stretching and the polymer stiffness can account for the unusual swelling behavior. Lastly, nonmonotonic swelling and shape change of the ring polymer are analyzed. We find out that the ring polymer is subject to most pronounced swelling at robust stiffness. Moreover, the maximum prolate shape is also observed at the same robust location.