CO₂ -Induced Morphological Transition of Co-Assemblies from Block-Random Segmented Polymers.

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Co-assembly is key for hierarchical nanostructured soft materials.
• Morphological transitions triggered by stimuli, especially CO2, remain poorly understood.

Purpose of the Study:

• To investigate the CO2-induced morphological transitions of co-assembled nanostructures.
• To explore the use of segmented copolymers for stimuli-responsive soft materials.

Main Methods:

• Co-assembly of segmented copolymers (P1-P2 and P1-P3) in a mixed solvent system.
• Induction of morphological changes using ferric ions and carbon dioxide (CO2).
• Characterization of resulting nanostructures (Janus micelles, wormlike micelles, core-shell micelles, spherical micelles).

Main Results:

• Janus micelles formed from P1-P2 co-assembly in the presence of ferric ions.
• Wormlike micelles formed from P1-P3 co-assembly.
• CO2 stimulation induced a transition from Janus to core-shell micelles.
• CO2 stimulation induced a transition from wormlike to spherical micelles.

Conclusions:

• Demonstrates CO2 as a "green" trigger for reversible morphological transitions in co-assembled soft materials.
• Highlights the potential of segmented copolymers for designing stimuli-responsive nanomaterials.
• Provides insights into the fundamental mechanisms governing co-assembly and morphological control.