Direct visualization of bottlebrush polymer conformations in the solid state
Direct visualization of bottlebrush polymer conformations in the solid state
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DOI：
10.1073/pnas.2109534118
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发表时间：
2021-10-05
影响因子：
11.1
通讯作者：
Wang, Muzhou
中科院分区：
文献类型：
--
作者：
Chan, Jonathan M.;Kordon, Avram C.;Wang, Muzhou
虽然单链的行为是聚合物科学基础不可或缺的一部分，但单链在固态下的清晰和令人信服的图像仍然没有被捕获。对于瓶刷聚合物，了解它们在散装材料中的构象是特别重要的，因为它们的延伸主链可以解释它们的自组装和机械性能，这些性能对许多应用都很有吸引力。在这里，单bottlebrush链可视化使用单分子定位显微镜研究它们的构象在聚合物熔体组成的线性聚合物。通过观察具有不同侧链长度和接枝密度的瓶刷聚合物，我们观察了分子结构与构象之间的关系。我们发现，瓶刷是显着更刚性的固态比以前测得的解决方案，持久性长度和侧链长度之间的比例关系偏离理论和模拟预测。我们讨论了这些差异，使用聚合物接枝纳米粒子，一个概念上类似的系统启发的机制。我们的工作为在完全由其他聚合物组成的环境中可视化单个聚合物链提供了一个平台，这可以回答聚合物科学中的一些悬而未决的问题。
Although the behavior of single chains is integral to the foundation of polymer science, a clear and convincing image of single chains in the solid state has still not been captured. For bottlebrush polymers, understanding their conformation in bulk materials is especially important because their extended backbones may explain their self-assembly and mechanical properties that have been attractive for many applications. Here, single-bottlebrush chains are visualized using single-molecule localization microscopy to study their conformations in a polymer melt composed of linear polymers. By observing bottlebrush polymers with different side chain lengths and grafting densities, we observe the relationship between molecular architecture and conformation. We show that bottlebrushes are significantly more rigid in the solid state than previously measured in solution, and the scaling relationships between persistence length and side chain length deviate from those predicted by theory and simulation. We discuss these discrepancies using mechanisms inspired by polymer-grafted nanoparticles, a conceptually similar system. Our work provides a platform for visualizing single-polymer chains in an environment made up entirely of other polymers, which could answer a number of open questions in polymer science.