论文标题
半灵性聚合物的限制溶液中的定向润湿和拓扑过渡
Orientational wetting and topological transitions in confined solutions of semi-flexible polymers
论文作者
论文摘要
尽管它们具有相当大的实用和生物学应用，但在密闭聚合物溶液中的分子特性，组装条件和自组织结构之间的联系仍然难以捉摸。在这里，我们探讨了球形限制中半柔性链的溶作二元序列，以在广泛的浓度范围内多个轮廓长度。我们从两个不同的四极性状态中揭示了原始的跨界，这两种状态的特征在于表面拓扑缺陷的常规四面体模式，即纵向，纬度或自发扭曲的双极结构，其密度增加。这些过渡以及它们所涉及的中介排列归因于定向润湿与液体结晶（LC）弹性各向异性的细微变化的结合。我们的分子模拟通过密度功能计算证实，并通过引入多个阶参数以及无监督的学习方案来量化拓扑缺陷的定位方案。我们的结果与连续列弹性理论的预测进行了定量一致，并证明了大分子的折叠和低分子量LCS的自组装的程度可能在同样的普遍原理中指导。
Despite their considerable practical and biological applications, the link between molecular properties, assembly conditions and self-organized structure in confined polymer solutions remains elusive. Here, we explore the lyotropic nematic ordering of semi-flexible chains in spherical confinement for multiple contour lengths across a wide regime of concentrations. We uncover an original crossover from two distinct quadrupolar states, both characterized by regular tetrahedral patterns of surface topological defects, to either longitudinal, latitudinal or spontaneously-twisted bipolar structures with increasing densities. These transitions, along with the intermediary arrangements that they involve, are attributed to the combination of orientational wetting with subtle variations in their liquid-crystal (LC) elastic anisotropies. Our molecular simulations are corroborated by density functional calculations, and are quantified through the introduction of several order parameters as well as an unsupervised learning scheme for the localization of topological defects. Our results agree quantitatively with the predictions of continuum nematic elasticity theories, and evidence the extent to which the folding of macromolecules and the self-assembly of low-molecular-weight LCs may be guided by the same, universal principles.
