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A Transiently Activated Rotaxane Mechanocatalyst
Diandian Deng1, Jiaojiao Xie1, Siwen Wang1
1School of Chemistry and Molecular Engineering, East China Normal University, Shanghai, P.R. China.
Angewandte Chemie (International Ed. in English)
|July 24, 2026
Summary
Mechanical force can now activate a novel catalyst that switches off when the force is removed. This recyclable mechanocatalyst shows potential for creating advanced self-healing and stress-reporting polymer materials.
Area of Science:
- Polymer Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Mechanocatalysts activate chemical reactions using mechanical force, promising for self-healing materials.
- Previous mechanocatalysts often rely on irreversible covalent bond breaking.
- Controlling catalyst activation and deactivation is crucial for practical applications.
Purpose of the Study:
- To develop a novel, transient mechanocatalyst activated by mechanical force.
- To create a recyclable catalyst that can be switched on and off.
- To explore the potential of this catalyst in solid-state polymerization.
Main Methods:
- Design and synthesis of a transient [2]rotaxane mechanocatalyst with a thiourea active site.
- Testing catalytic activity under mechanical force (impact, fatigue, compression).
- Evaluating catalyst recyclability and performance in solution and solid states.
Main Results:
- The [2]rotaxane catalyst is activated by mechanical force and spontaneously deactivates without it.
- Demonstrated the first example of a recyclable mechanocatalyst with undiminished efficiency over 5 cycles in solution.
- Achieved comparable catalytic efficiency in the solid state due to low activation force thresholds.
- Catalyzed ring-opening polymerization of lactide in the solid state via compression.
Conclusions:
- A novel, transient, and recyclable mechanocatalyst has been developed.
- This system offers controllable activation and deactivation in response to mechanical stimuli.
- The catalyst shows promise for developing advanced force-responsive polymer materials and solid-state polymerization.
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