2025-01-16 ノースウェスタン大学
With 100 trillion mechanical bonds per 1 square centimeter, the new material contains highest density of mechanical bonds ever achieved. Image by Mark Seniw, Center for Regenerative Nanomedicine
＜関連情報＞
- https://news.northwestern.edu/stories/2025/01/chainmail-like-material-could-be-the-future-of-armor/
- https://www.science.org/doi/10.1126/science.ads4968
機械的に連結した二次元ポリマー Mechanically interlocked two-dimensional polymers
Madison I. Bardot, Cody W. Weyhrich, Zixiao Shi, Michael Traxler, […], and William R. Dichtel
Science Published:16 Jan 2025
DOI:https://doi.org/10.1126/science.ads4968
Editor’s summary
A mechanically interlocked two-dimensional polymer forms as a layered solid that can be exfoliated in common organic solvents. Bardot et al. found that a molecule with four extended aromatic groups crystallizes in a layered structure supported by hydrogen bonds between hydroxyl groups. Infiltration of dialkyldichlorosilane was used to form siloxane linkages that created macrocyclic mechanical interlocks at every repeat unit. The addition of 2.5% by weight of this material to poly(ether imide) fibers increased their tensile modulus by 45% and ultimate stress by 22%. —Phil Szuromi
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.
