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Structural Characterization of a Covalent Monolayer Sheet Obtained by Two-Dimensional Polymerization at an Air/Water
Vivian Müller1, Feng Shao2, Milos Baljozovic3
1Department of Materials, Institute of Polymer Chemistry, ETH Zurich, Vladimir-Prelog-Weg 5, 8093, Zurich, Switzerland.
Angewandte Chemie (International Ed. in English)
|September 19, 2017
Summary
Researchers provide direct spectroscopic evidence of crosslinks and conversion in two-dimensional polymer sheets formed at an air/water interface. This advance enables better characterization of 2D polymer crystallinity and defects.
Area of Science:
- Materials Science
- Polymer Chemistry
- Surface Science
Background:
- Two-dimensional (2D) polymers synthesized at interfaces are promising materials.
- Characterizing their structure and crosslinking is crucial for applications.
- Direct spectroscopic evidence for 2D polymer formation and conversion has been lacking.
Purpose of the Study:
- To provide direct spectroscopic evidence for crosslink formation in 2D polymers.
- To determine the conversion achieved during polymerization at an air/water interface.
- To advance the characterization of covalently bonded monolayer sheets.
Main Methods:
- Two-dimensional polymerization at an air/water interface.
- Monolayer characterization techniques before and after transfer.
- Tip-enhanced Raman spectroscopy (TERS) and TERS mapping on Au(111) substrates.
Main Results:
- Direct spectroscopic evidence for the types of crosslinks formed in the 2D polymer.
- Quantification of the conversion achieved in the covalently bonded monolayer sheet.
- Successful transfer of monomer and polymer monolayers onto solid substrates for analysis.
Conclusions:
- This study offers the first direct spectroscopic evidence of crosslinking and conversion in 2D polymers.
- The methods allow for estimation of crystallinity and defect localization using percolation theory.
- This work represents a significant advancement for the field of 2D polymer synthesis and characterization.
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