Frustrated Lewis Pair Polymers as Responsive Self-Healing Gels
Meng Wang1, Fabio Nudelman1, Rebecca R Matthes1
1School of Chemistry, the University of Edinburgh , Joseph Black Building, David Brewster Road, Edinburgh EH9 3FJ, United Kingdom.
Journal of the American Chemical Society
|September 16, 2017
Summary
This study introduces macromolecular frustrated Lewis pairs (FLPs) for materials science. These polymer-based FLPs form dynamic, self-healing, and heat-responsive gels upon small molecule addition.
Area of Science:
- Polymer Chemistry
- Supramolecular Chemistry
- Materials Science
Background:
- Frustrated Lewis pairs (FLPs) are known for small molecule activation and catalysis due to steric hindrance preventing acid-base interaction.
- The application of FLPs in materials chemistry remains largely unexplored.
Purpose of the Study:
- To develop a fully macromolecular FLP system for materials applications.
- To investigate the formation and properties of FLP-based polymer networks.
Main Methods:
- Synthesis of linear copolymers with pendant sterically encumbered Lewis acids (boron) or Lewis bases (phosphorus) via controlled radical copolymerization.
- Investigating the interaction between B- and P-functionalized polystyrenes.
- Inducing network formation using diethyl azodicarboxylate as a small molecule cross-linker.
Main Results:
- Mixtures of B- and P-functionalized polystyrenes showed no inherent reaction due to steric bulk.
- Addition of diethyl azodicarboxylate led to rapid gel formation and network creation.
- The resulting polymer gel exhibited dynamic, self-healing, heat-responsive, and post-processing reshaping capabilities.
Conclusions:
- Macromolecular FLPs can be successfully constructed using functionalized copolymers.
- These polymer-based FLPs enable the formation of advanced dynamic materials with tunable properties.
- This work opens new avenues for FLP applications in materials science and engineering.
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