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Updated: Oct 21, 2025
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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
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Identification of Topotactic Surface-Confined Ullmann-Polymerization.
Dominik Dettmann1, Gianluca Galeotti1,2, Oliver MacLean1,3
1Centre Énergie, Matériaux et Télécommunications, Institut National de la Recherche Scientifique Department, 1650 Boulevard Lionel-Boulet, J3X1S2, Varennes, Québec, Canada.
Small (Weinheim an Der Bergstrasse, Germany)
|September 3, 2021
Summary
Topotactic polymerization on copper surfaces enables deterministic synthesis of ordered organic polymers, overcoming limitations of random diffusion. This method controls polymer structure by orienting reactants, leading to defect-free materials.
Area of Science:
- Surface Science
- Organic Chemistry
- Materials Science
Background:
- On-surface Ullmann coupling is vital for synthesizing organic structures.
- Random diffusion of reactants often leads to structural defects and polymorphism in polymers.
Purpose of the Study:
- To identify and understand a topotactic polymerization mechanism on Cu(110).
- To control the structure of polymers synthesized via on-surface Ullmann coupling.
Main Methods:
- Utilized temperature-programmed X-ray photoelectron spectroscopy and kinetic modeling.
- Performed Nudged Elastic Band calculations to analyze reaction mechanisms.
- Investigated differently-halogenated para-phenylenes on Cu(110) substrate.
Main Results:
- Identified a topotactic polymerization pathway for diiodobenzene on Cu(110).
- Demonstrated that reactant self-assembly and iodine structure dictate topotactic control.
- Found that inter-chain interactions (repulsion/attraction) determine diffusive vs. topotactic polymerization.
Conclusions:
- Topotactic polymerization offers a deterministic route to ordered organic polymers on surfaces.
- The study provides deep mechanistic insights into surface-confined Ullmann polymerization.
- Harnessing topotactic reactions is a viable strategy for defect-free polymer synthesis.
Keywords:
density functional calculationskineticsreaction mechanismssurface chemistrytime-resolved spectroscopyMore Related Videos
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