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Synthesis and Characterization of Metallopolymer Networks Featuring Triple Shape-Memory Ability Based on Different
Josefine Meurer1,2, Thomas Bätz1,2, Julian Hniopek3,4,5
1Laboratory of Organic and Macromolecular Chemistry (IOMC), Friedrich Schiller University Jena, Humboldstr. 10, 07743 Jena, Germany.
Polymers
|May 14, 2022
Summary
Researchers developed metallopolymer networks exhibiting triple shape-memory effects. These advanced materials utilize two distinct supramolecular crosslinks with different activation temperatures for shape control.
Area of Science:
- Polymer Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Shape-memory polymers (SMPs) offer tunable recovery properties.
- Multi-shape SMPs require multiple distinct switching mechanisms.
- Metallopolymers provide a versatile platform for creating dynamic crosslinks.
Purpose of the Study:
- To synthesize and characterize metallopolymer networks with triple shape-memory capabilities.
- To investigate the role of supramolecular crosslinks in enabling multiple shape recovery.
- To demonstrate the potential of metallopolymers for advanced shape-memory applications.
Main Methods:
- Free radical polymerization (FRP) for network synthesis.
- Complexation with metal salts to form supramolecular crosslinks.
- Isothermal titration calorimetry (ITC) to determine association constants.
- Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), FT-Raman spectroscopy, and thermo-mechanical analysis (TMA) for characterization.
Main Results:
- Successful synthesis of covalently crosslinked polymer networks with two distinct ligands.
- Selective formation of metal-ligand complexes with different association constants (K).
- Demonstration of two supramolecular crosslinks with distinct activation temperatures.
- Observation of excellent dual and triple shape-memory abilities via TMA.
Conclusions:
- Metallopolymer networks can be designed to exhibit multiple shape-memory effects.
- The distinct activation temperatures of supramolecular crosslinks are key to controlling multiple shape recovery.
- This work presents a promising route towards sophisticated multi-shape-memory materials.
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