Chemical kinetic mechanisms and scaling of two-dimensional polymers via irreversible solution-phase reactions
Name
194901_1_online.pdf
Description
Published version
Size
5.4 MB
Format
Adobe PDF
Checksum (MD5)
b225bf942dae0f166e05865c78616c87
Author(s)
Zhang, Ge
Zeng, Yuwen
Gordiichuk, Pavlo
Strano, Michael S
Date Issued
May 17, 2021
Journal
The Journal of Chemical Physics
Publisher
AIP Publishing
Citation
Ge Zhang, Yuwen Zeng, Pavlo Gordiichuk, Michael S. Strano; Chemical kinetic mechanisms and scaling of two-dimensional polymers via irreversible solution-phase reactions. J. Chem. Phys. 21 May 2021; 154 (19): 194901.
Version
Final published version
Abstract
Two-dimensional (2D) polymers are extended networks of multi-functional repeating units that are covalently linked together but confined to a single plane. The past decade has witnessed a surge in interest and effort toward producing and utilizing 2D polymers. However, facile synthesis schemes suitable for mass production are yet to be realized. In addition, unifying theories to describe the 2D polymerization process, such as those for linear polymers, have not yet been established. Herein, we perform a chemical kinetic simulation to study the recent synthesis of 2D polymers in homogeneous solution with irreversible chemistry. We show that reaction sites for polymerization in 2D always scale unfavorably compared to 3D, growing as molecular weight to the 1/2 power vs 2/3 power for 3D. However, certain mechanisms can effectively suppress out-of-plane defect formation and subsequent 3D growth. We consider two such mechanisms, which we call bond-planarity and templated autocatalysis. In the first, although single bonds can easily rotate out-of-plane to render polymerization in 3D, some double-bond linkages prefer a planar configuration. In the second mechanism, stacked 2D plates may act as van der Waals templates for each other to enhance growth, which leads to an autocatalysis. When linkage reactions possess a 1000:1 selectivity (γ) for staying in plane vs rotating, solution-synthesized 2D polymers can have comparable size and yield with those synthesized from confined polymerization on a surface. Autocatalysis could achieve similar effects when self-templating accelerates 2D growth by a factor β of 106. A combined strategy relaxes the requirement of both mechanisms by over one order of magnitude. We map the dependence of molecular weight and yield for the 2D polymer on the reaction parameters, allowing experimental results to be used to estimate β and γ. Our calculations show for the first time from theory the feasibility of producing two-dimensional polymers from irreversible polymerization in solution.
MIT Department
Massachusetts Institute of Technology. Department of Chemical Engineering
Terms of Use
Creative Commons Attribution
Persistent DSpace Link
DOI of Published Version
10.1063/5.0044050
