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Polymerization/Depolymerization-Induced Self-Assembly under Coupled Equilibria of Polymerization with Self-Assembly
Jiyun Nam1, Changsu Yoo1, Myungeun Seo1,2
1Department of Chemistry, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
Journal of the American Chemical Society
|May 8, 2024
Summary
Dynamic control of polymer chains through reversible polymerization and depolymerization allows for temperature-triggered self-assembly of block copolymers into tunable soft materials.
Area of Science:
- Polymer Chemistry
- Materials Science
- Supramolecular Chemistry
Background:
- Depolymerization offers a sustainable route to break down polymers into monomers.
- Reversible polymerization and depolymerization can be controlled by temperature.
- Self-assembly of block copolymers is crucial for creating nanostructures.
Purpose of the Study:
- To demonstrate dynamic control over block copolymer self-assembly using reversible polymerization/depolymerization.
- To investigate temperature-induced reversible morphological transitions in nano-objects.
- To explore the potential of these dynamic systems as soft materials.
Main Methods:
- Utilized ring-opening polymerization of δ-valerolactone initiated from poly(ethylene oxide).
- Employed temperature cycling to induce polymerization/depolymerization/repolymerization.
- Studied morphological transitions of block copolymer micellar nano-objects in selective solvents.
Main Results:
- Achieved reversible control over block copolymer self-assembly via temperature-swing.
- Demonstrated reversible morphological transitions (e.g., rod-sphere-rod, fiber-rod-fiber) by regulating the packing parameter.
- Observed that solvent selectivity enhances depolymerization at lower temperatures due to entropic effects.
Conclusions:
- Polymerization/depolymerization-induced self-assembly (PDISA) offers a novel method for dynamic nano-object formation.
- Temperature-responsive morphological changes in block copolymer micelles were successfully achieved.
- These dynamic soft materials exhibit potential for applications requiring tunable macroscopic properties like viscosity.
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