Center for Soft and Living Matter, Institute for Basic Science (IBS), Ulsan, South Korea.
Department of Chemistry, UNIST, Ulsan, South Korea.
Nat Commun. 2023 Feb 1;14(1):537. doi: 10.1038/s41467-023-36249-x.
Networks and gels are soft elastic solids of tremendous technological importance that consist of cross-linked polymers whose structure and connectivity at the molecular level are fundamentally nonuniform. Pre-failure local mechanical responses are not understood at the level of individual crosslinks, despite the enormous attention given to their macroscopic mechanical responses and to developing optical probes to detect their loci of mechanical failure. Here, introducing the extensophore concept to measure nondestructive forces using an optical probe with continuous force readout proportional to deformation, we show that the crosslinks in an elastic polymer network extend, fluctuate, and deform with a wide range of molecular individuality. Requiring little specialized equipment, this foundational single-molecule phosphorescence approach, applied here to polymer science and engineering, can be useful to a broad science and engineering community.
网络和凝胶是具有巨大技术重要性的软弹性固体，由交联聚合物组成，其分子水平的结构和连接性从根本上是非均匀的。尽管人们对其宏观力学响应以及开发光学探针以检测其力学失效位置给予了极大的关注，但在单个交联点的水平上，仍未理解预失效的局部力学响应。在这里，我们引入了延伸体的概念，使用具有与变形成正比的连续力读数的光学探针来测量非破坏性力，我们表明弹性聚合物网络中的交联点以广泛的分子个体性进行延伸、波动和变形。这种基础性的单分子磷光方法需要很少的专用设备，这里应用于聚合物科学和工程，可以为广泛的科学和工程界提供帮助。
