美国西北大学William R. Dichtel团队报道了机械互锁的二维聚合物。相关研究成果于2025年1月17日发表在《科学》。

机械键在含有互锁亚基的分子之间出现，例如一个大环穿过另一个大循环。在聚合物中，这些连接将赋予独特的机械性能和其他新兴行为，但有效形成机械键并使用简单单体构建块的聚合很少见。

该文中，研究人员介绍了一种固态聚合，其中一种单体渗透到另一种单体制备的晶体中，在二维（2D）聚合物的每个重复单元处形成大环和机械键。这种机械联锁的2D聚合物形成为层状固体，在常见的有机溶剂中很容易剥离，从而能够使用先进的电子显微镜技术进行光谱表征和原子分辨率成像。

2D机械互锁聚合物很容易在多图尺度上制备，再加上其溶液加工性，使得使用Ultem轻松制造出具有增强刚度和强度的复合纤维成为可能。

附：英文原文

Title: Mechanically interlocked two-dimensional polymers

Author: Madison I. Bardot, Cody W. Weyhrich, Zixiao Shi, Michael Traxler, Charlotte L. Stern, Jinlei Cui, David A. Muller, Matthew L. Becker, William R. Dichtel

Issue&Volume: 2025-01-17

Abstract: Mechanical bonds arise between molecules that contain interlocked subunits, such as one macrocycle threaded through another. Within polymers, these linkages will confer distinctive mechanical properties and other emergent behaviors, but polymerizations that form mechanical bonds efficiently and use simple monomeric building blocks are rare. In this work, we introduce a solid-state polymerization in which one monomer infiltrates crystals of another to form a macrocycle and mechanical bond at each repeat unit of a two-dimensional (2D) polymer. This mechanically interlocked 2D polymer is formed as a layered solid that is readily exfoliated in common organic solvents, enabling spectroscopic characterization and atomic-resolution imaging using advanced electron microscopy techniques. The 2D mechanically interlocked polymer is easily prepared on multigram scales, which, along with its solution processibility, enables the facile fabrication of composite fibers with Ultem that exhibit enhanced stiffness and strength.

DOI: ads4968

Source:https://www.science.org/doi/10.1126/science.ads4968