Liebetreu Maximilian, Likos Christos N
Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria.
Soft Matter. 2020 Sep 30;16(37):8710-8719. doi: 10.1039/d0sm01309a.
Semiflexible ring polymers are known to exhibit clustering behavior and form stacks in concentrated solutions. Recently, weak shear was suggested to re-orient these stacks with flow, a phenomenon more easily visible in more concentrated solutions [Liebetreu et al., ACS Appl. Polym. Mater., 2020, 2(8), 3505-3517, DOI: 10.1021/acsapm.0c00522]. In this work, we investigate the impact of mixing linear chains and rings in a similar system under shear, studying clustering in the presence of semiflexible, rod-like chains. We present a correlation between chain monomer fraction and clustering behavior as linear chains take up less space, thus decreasing the system's effective density and, subsequently, clustering. However, we suggest mixtures with a low chain concentration to maintain or potentially enhance clustering at equilibrium while this effect is destroyed under shear. The mixing of chains and rings may therefore be used to create more strongly organized structures susceptible to reorientation via weak shear.
已知半柔性环状聚合物在浓溶液中会表现出聚集行为并形成堆叠。最近，有人提出弱剪切会使这些堆叠随流动重新取向，这种现象在浓度更高的溶液中更容易观察到[利贝特雷等人，《美国化学会应用聚合物材料》，2020年，2(8)，3505 - 3517，DOI: 10.1021/acsapm.0c00522]。在这项工作中，我们研究了在剪切作用下类似体系中线性链和环混合的影响，研究了在存在半柔性棒状链的情况下的聚集现象。我们提出了链单体分数与聚集行为之间的相关性，因为线性链占据的空间较小，从而降低了体系的有效密度，进而减少了聚集。然而，我们认为低链浓度的混合物在平衡时能维持或潜在增强聚集，而这种效应在剪切作用下会被破坏。因此，链和环的混合可用于创建更有序的结构，这些结构易于通过弱剪切重新取向。
