Phase behavior of symmetric diblock copolymers under 3D soft confinement

Area of Science:

• Polymer Science
• Materials Science
• Soft Matter Physics

Background:

• Diblock copolymers self-assemble into ordered structures.
• Understanding confined copolymer behavior is crucial for materials design.
• Soft confinement offers unique templating possibilities.

Purpose of the Study:

• Investigate the phase behavior of symmetric diblock copolymers under 3D soft confinement.
• Explore the influence of homopolymer selectivity and confinement degree on self-assembly.
• Identify and characterize novel emergent morphologies.

Main Methods:

• Utilized self-consistent field theory (SCFT) simulations.
• Modeled soft confinement using binary blends of diblock copolymers and homopolymers.
• Performed free energy analysis to understand structural transitions.

Main Results:

• Observed diverse morphologies including stacked lamellae (SL) and non-lamellar structures (onion, hamburger, etc.).
• Morphological transitions were linked to confinement degree and homopolymer selectivity.
• Demonstrated a reversible first-order phase transformation between SL and onion-like (OL) structures.

Conclusions:

• Soft 3D confinement provides a versatile route to control diblock copolymer self-assembly.
• Homopolymer selectivity and confinement degree are key parameters for tuning emergent structures.
• Findings offer insights into designing complex nanostructures for advanced materials.